Category Archives: Lifestyle and Heart Disease

Longevity: Lifespan, Healthspan and Swimming Underwater At Age 98

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Eugene and Naomi.

The skeptical cardiologist has a few nonagenarian patients who seemingly defy the ravages of aging and remain vibrant and active into their late 90’s.

Eugene, for example, still ballroom
dances regularly with his wife, Naomi and swims underwater significant distances.

In this video, recorded when he was 97, you can see him swim the length of a swimming pool underwater

As life expectancy at birth has increased  from 35 years in 1900 to over 80 years now, we see more and more individuals reaching their nineties. Ongoing research seeks to further extend our lifespan.

But just as important as increasing lifespan is increasing healthspan, the portion of the life span during which function is sufficient to maintain autonomy, control, independence, productivity and well-being.

Eugene is an example of someone with a long lifespan and healthspan and this is what we truly seek, the combination of living well and living long.

Peter Attila writes that lifespan is driven by how long one can avoid the onset of diseases caused by atherosclerosis such heart attacks and strokes (see my  discussions on subclinical atherosclerosis here), cancer and neurodegenerative disease.

Healthspan,  Attila writes, is about preserving three elements of life as long as possible:

  1. Brain—namely, how long can you preserve cognition and executive function

  2. Body—specifically, how long can you maintain muscle mass, functional strength, flexibility, and freedom from pain

  3. “Spirit”—how robust is your social support network and your sense of purpose.

Problems with the body result in frailty, recognized as a major cause of disability and related falls, hospitalizations and death in the elderly.

The single best tool for warding off frailty appears to be physical exercise.

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Eugene and Noami tripping the light fantastic in our exam room

So, if you want to life a long life with lots of quality years at the
end of that life be like Eugene: swim and dance with your loved ones. Keep moving, stretch and exercise in some manner regularly.

Gerontologically Yours,

-ACP

Should Fitness Be A Vital Sign?

The skeptical cardiologist routinely probes his patients’ activity and exercise levels and encourages them to engage in 150 minutes of moderate exercise weekly. However, I’m somewhat skeptical of the benefit of treating such assessments as a vital sign (like blood pressure or heart rate)  as a recent AHA scientific statement suggests.

I can only envision still another item  on a chart checklist that will have to be recorded in the EHR or already over-worked physicians will have their payments withheld.

The AHA statement suggests that ideally we should be measuring  our patients’ fitness by obtaining  maximal oxygen consumption (VO2 max) utilizing an expensive and rarely utilized cardiopulmonary exercise test. Failing that we should consider doing a treadmill stress test. Failing that, rather than utilizing my simple question to patients: “How active have you been?”,  the statement recommends doctors utilize some sort of formal questionnaire to estimate their patients’ cardiorespiratory fitness (CRF) such as the one at World Fitness Level.

I went online to take this CRF estimator (based on this paper) and I remain skeptical.

The online site and  a free smartphone app both ask the following questions:

  • Country and City
  • Ethnicity
  • Highest Level of Education
  • Gender/Age/Height/Weight
  • Resting and Maximal Pulse
  • How often do you exercise?
  • How long is your workout each time? (over/under 30 minutes)
  • How hard do you train? (I had to choose between “I go all out”or “Little hard breathing and sweating”)

 

screen-shot-2016-12-03-at-11-33-13-amWhen you have finished answering the questions you are given an estimate of your fitness age. When I did this online a few days ago and answered truthfully I got the result to the right: I had the fitness of a 41 year old with an estimated VO2 max of 49 ! (interestingly this estimate corresponds exactly with VO2 max derived from a recent stress test I completed.)

I used the app (which unlike the online version did not ask me my waistline measurement) and changed a few parameters:

  • I increased my resting heart rate or pulse  from 60 to 68 beats per minute (BPM)
  • I increased my maximal heart rate from what I know is 158 BPM to what the app calculated (173 BPM, which makes no sense)
  • I switched from exercising 2-3 times per week  and longer than 30 minutes  at “all out” level to the lowest level for all 3 questions.

The change was dramatic and depressing: I went from 39 years old to 67 years old in the bat of an eyelid!img_8073

 

 

 

The app and online site direct you to a non-profit site where you can get information on a 7 week program to increase your fitness level. I haven’t checked this out.

I’ll be trying out this CRF estimator on my patients: assessing whether it adds anything to my usual line of questioning on activity and fitness.

I encourage you to give the CRF estimator a try. Let me know in the comments how you feel it works for you. Does it motivate you to exercise more knowing that, for example, your fitness age is substantially higher than your chronological age?

Are We Springing Forward to Death?: Daylight savings time and myocardial infarction

Tonight we will lose an hour of our lives when we observe Daylight Savings Time (DST).

Media reports suggest that DST, beyond robbing of us that nocturnal hour in the spring are also increasing our risk of heart attack (myocardial infarction or MI) and death.

Is this a valid concern or just media hype on a slow news day?

Scientific studies on this topic are mixed.

A recent study from Finland found MI rates increased 16% on the Wednesday after spring DST time change and dropped by 15% on the Monday after fall DST time change.

A 2015 German study found no difference in MI rate in the 3days or 1 week after spring or fall DST transitions.

However, some American studies have detected a bump in MI rate on the day after DST transition in the spring and a similar drop in MI rate on the day after the fall DST change.

A study of 42000 patients undergoing acute PCI for MI in Michigan found that

“The Monday following spring time changes was associated with a 24% increase in daily AMI counts (p=0.011), and the Tuesday following fall changes was conversely associated with a 21% reduction (p=0.044). No significant difference in total weekly counts or for any other individual weekdays in the weeks following DST changes was observed.”

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They concluded:

Our data argue that DST could potentially accelerate events that were likely to occur in particularly vulnerable patients and does not impact overall incidence. There is considerable controversy over the health and economic benefits of DST, and some authorities have argued that this practice should be abandoned.17 Although we are unable to comment on the merits of these arguments, our data suggest that while such a move might change the temporal fluctuations in AMI, it is unlikely to impact the total number of MIs in the broader population.

Mondays, in general, are the days of the week on which most MIs occur. This has been attributed to an abrupt change in the sleep–wake cycle and increased stress in relation to the start of a new work week

Manipulations of the sleep–wake cycle have been linked to imbalance of the autonomic nervous system, rise in proinflammatory cytokines and depression so presumably the additional disruption created by DST adds to this effect.

However, the data suggest that this very weak effect means only that if you were going to have an MI in the next week, after DST it is more likely to occur on the Monday of that week than on another day. Your overall risk of MI is not changed.

From a public health standpoint the major conclusion is that emergency rooms and cath labs should consider increasing staffing by 24% on the Monday after the spring DST time change.

I don’t think this is a significant factor for my patients. We have to deal with events and stressors that influence our sleep-wake cycle constantly. Good planning and sleep hygiene are the keys to success and reducing stress.

So, fear not the grim reaper as you set your clocks forward tonight.

Circadianly yours,

-ACP

PHOTO: PAVEL ŠEVELA/WIKIMEDIA COMMONS

 

Can The Garmin Vivosmart (Or Any Inactivity Monitor) Make You Healthier?

Americans do a lot of sitting. We sit in our cars, we sit watching TV , we sit reading or when interfacing with our computers and often our work involves many hours of sitting in front of a computer.

All this sitting or sedentariness  has been associated with an increased risk of obesity, metabolic syndrome, type 2 diabetes, and cardiovascular disease (CVD) mortality,

One recent study concluded

 “limiting sitting to <3 h/day and limiting television viewing to <2 h/day may increase life expectancy at birth in the USA by approximately 2.0 and 1.4 years, respectively, assuming a causal relationship.”

Even if you make your way to the gym and  meet current physical activity guidelines, excessive sedentary behavior may have adverse implications, particularly if you are older.

Recent studies suggests that longer-term consequences of not engaging in moderate to vigorous physical activity (too little exercise) are different from those of habitual sedentary behavior.

Dr. James Levine has been a leader of the “anti-chair mafia” and research on the negative effects of sedentariness and has written a book entitled “Get Up! Why Your Chair is Killing You and What You Can Do About It” , available here.

Sitting Is Not NEAT!

The energy expended during daily life (exclusive of purposeful exercise) has been measured with special sensor equipped underwear and is termed non exercise activity thermogenesis (NEAT).

Individuals who are lean have high NEAT. They are up and moving around 2 and  1/4 hours per day more than those who are obese and burn an extra 350 kcl/day of energy.

I advise all my patients to move as much as possible during their normal work or leisure day. Take frequent walking breaks, climb stairs, attach your computer to a treadmill, do anything to avoid prolonged sitting.

Activity and Inactivity Monitoring

You can now easily monitor your activity during the day with one of multiple smartphone apps and/or an associated wearable.

The skeptical cardiologist plunged into the wearable activity monitor world recently and purchased a Garmin Vivosmart (engadget review entitled “where fitness band meets smartphone”  here.)

I chose it from all the competing devices because of the following features

  • pairs with iPhone to sync data and display iPhone calls/messages-
  • monitors movement during sleep
  • monitors inactivity
  • monitors steps taken

I plan to report more extensively on all the features of this cool gizmo after I’ve had it longer.

Promotion of Physical Activity

The Vivosmart does a number of things that are designed to promote physical activity.

steps
The Vivosmart telling me I have taken 11, 639 steps. These were all taken during work, walking between patient rooms and between the hospital, the OR and my office. A read out on my steps motivates me to move more, take stairs, and embrace movement as a valuable thing.

It counts your steps pretty reliably and can monitor your heart rate when paired with a chest heart rate monitor.

It will help you visualize how close you are to reaching your steps per day goal and congratulate you when you reach it.

In addition it monitors your activity and takes note of your inactivity.

If you haven’t moved sufficiently in one hour it vibrates and displays “MOVE!” on its LEDs. If you don’t move enough to satisfy its criteria it will remind you every 15 minutes thereafter to MOVE!.

This sounds good on paper but it didn’t; work that well in practice for me.

A typical day at the office for me involves a lot of brief bursts of walking, some stair climbing, and a fair amount of standing.

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The Vivosmart inactivity monitor, telling me that I have been inactive for 41 minutes. In 19 minutes it will warn me to move by vibrating and flashing. I’ve been active this whole time, however, never sitting more than 10 minutes.

For instance, I walk to the patient exam room and sit down to take the patient’s history. At some point I stand up and exam the patient. When the visit is done I either walk back to my office to complete the office note or go to the next exam room. There is very little prolonged sitting occurring but these frequent, brief bursts of activity do no reset the Garmin Vivosmart.

Prolonged sitting is really what we want to avoid but the Vivosmart will only reset your inactivity meter if you walk continuously about 200 steps. Standing still even if interspersed with brief bursts of walking for less than two min,tes will not reset it.

If your job or normal day consists mostly of sitting for prolonged periods of time then this reminder to move may be helpful. However, for zero dollars you could  program your cell phone to go off every hour and serve essentially the same function.

I heartily endorse anything that gets my patients up and moving and off the couch. I think the Garmin Vivosmart (and other similar fitness trackers) is a step in the right direction and can lend focus and motivation to the goal of keeping active during the day.

To accurately measure NEAT, however, we may need magic wired underwear, something the public may not be ready for :).

-spending entirely too much time sitting and blogging,

-ACP

Is Exercise Impotent In Preventing Obesity?

What if all that exercise that authorities have been recommending  is not helping to stem the rising tide of obesity?

What if all calories don’t have the same ability to add fat?

These twin heresies fly in the face of the usual dogma on the cause of obesity: more calories in (gluttony) than calories out (sloth). The skeptical cardiologist has been pondering these possibilities for some time, since reading Gary Taubes book Good Calories, Bad Calories.

I have been advising my patients through this blog and during office visits that added sugar and  refined  carbohydrates are much more of a culprit in their  weight gain than fat, thus embracing the concept that there are good calories and bad calories

Exercise and Obesity

5Boro Bike Riders crossing the summit of the Queensboro aka 59th Street aka "Feelin Groovy" Bridge

But I also spend a lot of time during my office visits discussing activity levels and encouraging my patients to engage in moderate aerobic physical activity for at least 150 minutes per week.

I do this because there is good evidence that regular physical activity is associated with lower cardiovascular risk, cancer risk, mortality, and improved brain, muscle, and bone function. Exactly  what level and type of exercise is needed to reap these benefits is still up for debate.

I, personally, engage in regular moderate exercise and I think it helps maintain my weight where I want it.

Throwing Down the Gauntlet

A recent editorial in the British Journal of Sport Medicine stridently  makes the claim that exercise is not useful for weight loss as conventional wisdom teaches and that the food industry has been promoting exercise while simultaneously promoting junk food and sugar-sweetened beverages (The link I provided is no longer active because the journal has removed the editorial -“This paper has been temporarily removed following an expression of concern.”)

The authors wrote:

“members of the public are drowned by an unhelpful message about maintaining a healthy weight through calorie counting, and many still wrongly believe that obesity is entirely due to lack of exercise. This false perception is rooted in the Food Industry’s Public Relations machinery, which uses tactics chillingly similar to those of big tobacco. “

Root Causes of Obesity

It would appear that science cannot tell us with total certainty what the cause of our current obesity epidemic is.

After publishing a paper in 2014 that suggested Americans had become less active over the last 20 years, Ladabaum, et al admitted this:

“Although there is no clear answer at this time regarding the relative contribution of energy intake or physical activity (or other variables including dietary components, patterns of activity, and environmental factors, including the gut micro biome) to the public health problem of obesity, we believe that public health messages should continue to emphasize the importance of both a healthy diet and remaining physically active throughout life.”

Is Exercise Amount  A Cause or Effect?

In my own practice, I have observed a tendency for  those patients who regularly exercise or have very physically active jobs to stay thin whereas those who don’t exercise, especially if they have sedentary jobs or are retired, tend to be obese and gain weight.

But, I also note that those patients who take my recommendations on exercise to heart  are also listening to my advice in other areas, including diet and medications and are, in general, much more proactive about their health.

Therefore, I can’t say for sure whether it is the exercise  or the other aspects of a healthy lifestyle (including diet)  being followed in any individual patient that is keeping the pounds off. How much my patients move during the day when they are not specifically exercising may also be playing a role and is hard for me to assess.

There is also the mind-boggling possibility, as Gary Taubes has written about (here and in his book Why We Get Fat) that our genetics are driving both our activity levels and our food consumption:

Ultimately, the relationship between physical activity and fatness comes down to the question of cause and effect. Is Lance Armstrong excessively lean because he burns off a few thousand calories a day cycling, or is he driven to expend that energy because his body is constitutionally set against storing calories as fat? If his fat tissue is resistant to accumulating calories, his body has little choice but to burn them as quickly as possible: what Rony and his contemporaries called the “activity impulse”—a physiological drive, not a conscious one. His body is telling him to get on his bike and ride, not his mind. Those of us who run to fat would have the opposite problem. Our fat tissue wants to store calories, leaving our muscles with a relative dearth of energy to burn. It’s not willpower we lack, but fuel. “

I’m not ready to accept the heresy that exercise and activity have nothing to do with weight gain or loss. I, like most cardiologists, walk the walk and talk the talk of regular vigorous exercise for health benefits, extended longevity, cardiovascular fitness and for helping in weight control.

Exercise is not the be all and end all of weight control because increased consumption of bad or good calories can overcome the most prolonged and intense workouts but it is a useful adjunct.

Still exercising regularly,

-ACP

Dealing With The (Cardiovascular) Cards You’ve Been Dealt

The skeptical cardiologist was in Atlanta recently  visiting  his Life Coach (LCOSC). Oddly enough, the wife of the LCOSC (who I’ll call Lisa) had just undergone a coronary calcium scan  and it came back with a high score.  Most women her age (58 years old) have a zero score but hers came back at 208 .

What is the significance of a calcium score of 208 in this case?

The CT scan for calcium (discussed by me in more detail here) focuses entirely on quantifying the intense and very specific kind of x-ray absorption from calcium. The three-dimensional resolution of the scan is such that the coronary arteries which supply blood to the heart can be accurately located and the amount of calcium in them very accurately and reproducibly added up. Calcium is not in the arteries normally and only accumulates as atherosclerotic plaque builds up over time. The build up of fatty plaque (atherosclerosis) is the major cause of coronary artery disease (CAD, sometimes termed coronary heart disease (CHD)) which is what causes most heart attacks and most death in both men and women in the U.S.

We can enter Lisa’s numbers into the online MESA calculator to see how she compares to other white 59 year old women. The calculator tells us that 72% of her peers have a zero calcium score and a score of 208  is higher than 95% of her peers. Although the 95th percentile is a good place to be for SAT scores it is not for atherosclerosis. This means substantial amount of fatty atherosclerotic plaque has built up in the arteries and puts the individual at significantly greater risk for heart attack and stroke. A calcium score of 100-300 confers a 7.7 times increased risk compared to an individual with similar risk factors with a zero calcium score.

Most of the risk factors that we can measure to assess one’s risk of heart attack (blood pressure, diabetes, smoking) were absent in Lisa. Her cholesterol levels had risen in the last 10 years but when I entered her numbers (total cholesterol 221, HDL 68) into the ASCVD risk estimator her 10 year risk came back at 2.5%. This is considered low and no treatment of cholesterol would be advised by the new guidelines.

The only clue that her cardiologist would have that Lisa has advanced premature atherosclerosis is that her mother had coronary heart disease at an early age, something we call premature CAD. Her mom at the age of 62 suffered a heart attack and had a stent placed in one of her coronary arteries. The occurrence of significant premature CAD in a parent or sibling  substantially increases the chances that a patient will have premature CAD and the earlier it occurred in the parent or sibling the higher the risk.

Some of this excess risk is transmitted by measurable risk factors such as hypertension and hyperlipidemia and some through lifestyle factors but the majority of it is through genetic factors that we haven’t fully identified.

How much of an individual’s risk for heart attack  is determined by genetics versus lifestyle?

A large Swedish study found that adopted men and women with at least one biological parent with CHD were 1.5 times more likely to have CHD than adoptees without. In contrast, men and women with one adoptive parent were not at increased risk.

Since 2007 an intense project to identify genetic factors responsible for CAD has been underway at multiple academic centers. Thus far 50 genetic risk variants have been identified. According to Dr. Robert Roberts

” All of these risk variants are extremely common with more than half occurring in >50% of the general population. They increased only minimally the relative risk for coronary artery disease. The most striking finding is that 35 of the 50 risk variants act independently of known risk factors, indicating there are several pathways yet to be appreciated, contributing to the pathogenesis of coronary atherosclerosis and myocardial infarction. All of the genetic variants seem to act through atherosclerosis, except for the ABO blood groups, which show that A and B are associated with increased risk for myocardial infarction, mediated by a prolonged von Willebrand plasma half life leading to thrombosis”

 How well do the standard risk factors capture the individuals risk for heart attack?

The standard approach to estimating risk fails in about 25% of individuals as it does not accurately convey the high risk of the patient with family history and it overestimates risk in many elderly individuals who have an excellent family history.

It is in these patients that testing for the actual presence of atherosclerosis, either by vascular screening or coronary calcium is helpful.

Reducing The Excess Risk of Premature CAD

For many individuals there are clear-cut lifestyle changes that can be implemented once advanced CAD is identified: cigarette smoking cessation, weight loss through combinations of diet and exercise with resulting control of diabetes, However, many patients like Lisa, are non-smokers, living a good lifestyle, eating an excellent diet with plenty of fresh fruit, vegetables, fish and healthy oils and  without obesity or diabetes. There is no evidence that modifying lifestyle in this group is going to slow down an already advanced progression of atherosclerosis.

Patients like Lisa have inherited predisposition to CAD, it is not due to their lifestyle.

Lisa’s cardiologist  suggested she get a copy of Dr. Esselstyn’s book “Prevent and Reverse Heart Disease”. This book, based on the author’s experience in treating 18 patients with advanced CAD espouses an ultra low fat diet. The author declares that “you may not eat anything with a face or a mother (meat/poultry/fish)” and bans  full fat dairy products and all oil (“not even a drop”)

Such “plant-based diets” (codeword for vegan or vegetarianism) lack good scientific  studies supporting efficacy and are extremely hard to maintain long term. There is nothing to suggest that Lisa’s long term risk of heart attack and stroke would be modified by following such a Spartan dietary regimen.

Her cardiologist did recommend two things proven to be beneficial in patients with documented advanced CAD: statins and aspirin.

Taking a statin drug will arrest the atherosclerotic process and reduce risk of heart attack and stroke by around 30% as I’ve discussed here and here.

An aspirin is now indicated since significant atherosclerosis has now been documented to be present as I’ve discussed here.

We can blame a lot of heart disease on lifestyle: poor diets and lack of exercise are huge factors leading to obesity, diabetes, hypertension and hyperlipidemia, but in many patients I see who develop heart disease at an early age, lifestyle is not the issue, it is the genetic cards that they have been dealt.

Until we develop reliable genetic methods for identifying those at high risk it makes sense to utilize methods such as vascular screening or coronary calcium to look for atherosclerosis in individuals with a family history of premature CAD.

Once advanced atherosclerosis is identified, we have extremely safe and effective medications that can help  individuals like Lisa deal with the cardiovascular cards they have been dealt.

 

 

Does Any Amount of Leisure-Time Running Reduce Your Risk of Heart Attack?

1310552547_gumpThe skeptical cardiologist dislikes running. When I start running my whole body seems to be telling me I am making a serious mistake. After running, my knees hurt (worse than the normal level of pain) and if I do enough of it, my hips hurt too.

Despite this, I have incorporated running into my exercise routine over the last few years since I stopped playing tennis. I primarily get my aerobic exercise now by using elliptical type devices and I try to get at least 150 minutes of vigorous elliptical work per week. About once a week, I run a mile on a treadmill at 6 MPH.

My current patient exercise recommendation is for 150 minutes of moderate intensity aerobic exercise.  I have advised patients in the past, that walking at a moderate pace was adequate exercise, and I’ve felt, based on prior studies, that running was not necessary to achieve the cardiovascular benefits of exercise.

Any Running Associated With Lower Risk of Dying

A new study published recently in JACC has made me reconsider this advice.

As part of a prospective longitudinal cohort study at the Cooper Clinic in Dallas, Texas, Lee, et al. looked at data from a group of 55,137 adults on whom they had information on running or jogging activity during the previous 3 months.

To reduce confounding bias in the association between running and mortality, the total amount of other physical activities except running was adjusted in all multivariable regression models.

They obtained information on death from The National Death Index and over 15 years found 3,413 all-cause death and 1,217 deaths from cardiovascular disease.

Those individuals who described themselves as having done any running in the last 3 months had a 30% lower risk of all-cause mortality and a 45% lower cardiovascular mortality.

As you might expect, the non-runners were older, smoked more and were fatter. The investigators ran analyses that controlled for the differences in these factors. The protective effect of running, even a small amount, persisted, regardless of age, gender, body mass index, smoking or alcohol consumption.

Amazingly, it didn’t matter how much you ran.

This finding is quite remarkable.

Those who ran <51 minutes per week did just as well as those who ran >176 minutes per week.

Of the 20,67 that had two examinations, those who were runners at both examinations had the best outcomes with a 50% lower risk of CVD mortality.

These findings are not definitive. We need more studies in this area but they are food for thought.

Why Would Running Be A Better Form of Exercise For Your Heart

Some thoughts…

Perhaps the person who doesn’t want to run has a fundamentally different mindset about his/her health than the person who is willing to run just a little bit. Does this inclination to run mirror the person’s overall approach to their health? We can assess factors like cigarette smoking, obesity, diabetes and cholesterol but there are likely (so far) intangible factors that contribute to our health that tend to cluster with a pro-active health attitude.

Why do I run? After all, I don’t like it, it hurts my knees and I didn’t think it was contributing to my overall health. I did the mile run for a few reasons:

Running a mile in 10 minutes served as a milestone, a fixed goal if you will, for my cardiovascular fitness. I can get a very good idea of where I’m at by measuring my heart rate. I’m 60 years old and my predicted maximal heart rate (220 minus age) is 160. When I’m out of shape, my heart rate will get as high as 155 BPM during the mile, when in shape it is 10 BPM lower. 145 BPM is 91% of my predicted maximal HR.

My sense is  that a good goal for cardiovascular fitness is to get the heart rate up to 90% or so of your predicted maximal. It may be that running more reliably gets you to that threshold than other activities.

Also, as the significant other of the skeptical cardiologist points out, “you can’t cheat at running.” There’s a certain amount of effort you have to put into it and there’s no way to escape it as there is on a bicycle or an elliptical. With walking you could choose a speed ranging from the snail-like up to 4 MPH or so.

Those who don’t run may also have orthopedic limitations (plantar fasciitis, osteoarthritis, rheumatoid arthritis) or pulmonary problems (COPD, asthma) or undiagnosed heart problems (heart failure, valve defects, rhythm problems) that are not captured by the examinations the investigators performed.

These findings, the authors of the paper suggest, may make people more likely to run:

“Because time is one of the strongest barriers to participate in physical activity, this study may motivate more people to start running and continue to run as an attainable health goal for mortality benefits. Compared with moderate-intensity activity, vigorous-intensity activity, such as running, may be a better option for time efficiency, producing similar, if not greater, mortality benefits in 5 to 10 min/day in many healthy but sedentary individuals who may find 15 to 20 min/day of moderate-intensity activity too time consuming.”

Some Possible Mechanisms For The Benefits of Running

As I was putting the finishing touches on this post I notice that the Sept 23 issue of the Journal of the American College of Cardiology sitting in front of me has two articles that are directly relevant to this issue. I haven’t had time to analyze these in detail but the conclusions of the first study  are that

“low doses of casual, lifelong exercise do not prevent the decreased compliance and distensibility observed with healthy, sedentary aging. In contrast, 4 to 5 exercise sessions/week throughout adulthood prevent most of these age-related changes”

Thus, the mechanism through which running or more “committed” exercising improves survival could be mediated through improving the diastolic properties of the heart.

I spent most of my academic cardiology career studying diastolic function and it is an incredibly complicated and poorly understood area. Simply put, the heart has to contract to pump out blood (we call this systole) then it has to fill back up with blood (we call this diastole). With aging, the heart’s ability to contract doesn’t change but its ability to fill changes dramatically. Thus, diastolic properties become impaired with aging and this study suggests that dedicated regular exercise prevents that.

The other study showed that regular exercise helps to slow  age-related increase in blood pressure.  Lower blood pressure with aging could be a mechanism for preventing the age-related decline in diastolic performance of the heart.

Changing Exercise Prescription

From now on when I talk to my patients about exercise, I will inquire about running specifically and I’ll mention these studies which suggest a little running may go along way toward forestalling the aging process of the heart and lowering their risk of dying.

 

Death and Marriage in The Big Easy

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Built in 1857 for Richard Terrell, a wealthy cotton broker originally from Natchez, Mississippi, the Terrell House is a grand three story Italianate stucco-over-brick mansion. The main house features porches, galleries, and balconies framed in ornate cast iron and a brick New Orleans courtyard complete with several fountains and lush vegetation.

The Skeptical Cardiologist is not just researching low carb diets in The Big Easy. He has also been investigating the effects of marriage on cardiovascular risk.

I and the significant other of the skeptical cardiologist stayed at the wonderful Terrell House, a  bed and breakfast nestled among the magnolias on Magazine Street in the Garden District of New Orleans. There, we participated in the marriage of our close friends, Dave and Barb.

Was marrying a heart healthy choice for Dave? for Barb?

Science seems to tell us yes. Marriage has been associated with a lower risk of cardiovascular disease compared to being single or divorced in multiple studies and for both sexes.

A study of the rate at which individuals in Finland developed what are termed acute coronary syndromes or ACS (think of these as heart attacks or heart attacks about to happen) showed that ACS events were approximately 58–66% higher among unmarried men and 60–65% higher in unmarried women, than among married men and women in all age groups.

The chance of dying within 28 days of an ACS were even worse for the unmarried. These mortality rates were found to be 60–168% higher in unmarried men and 71–175% higher in unmarried women, than among married men and women.

This meant a rate of death of 26% in the 35-64-year-old married men, 42% in men who had previously been married, and 51% in never-been-married men. Among women, the corresponding figures were 20%, 32%, and 43%.

As with all such observational studies, association does not prove causation.

How on earth does being married confer a lower risk of developing cardiac problems and halving of the death rate once one has an ACS?

Some speculation from the authors:

1.  Perhaps a poor health status leads to not getting married or getting divorced more frequently.

2.  Perhaps married people have better health habits and enjoy higher levels of social support than the unmarried which promotes lower risk

3. Perhaps prospects in the pre-hospital phase are better because of earlier intervention (wife bugging husband to get that indigestion checked out)

Do I believe that Dave and Barb have suddenly halved their risk of dying from cardiovascular disease because they tied the knot last night?  Not at all!

Nothing has fundamentally changed in their lives that I can see that will have any significant impact on either one’s risk of a heart attack.

If Dave were a true bachelor and not in a committed monogamous relationship I can see certain factors that marriage would modify: perhaps unmarried Dave would be more inclined to engage in risky behaviors such as binge drinking, cigarette smoking, unhealthy food consumption or staying out late partying and  listening to wild music. Perhaps married Dave’s wife will be watching over him carefully for any signs or symptoms of heart disease and encouraging an early visit to the doctor to get checked out.

Perhaps the presence of kids limits the married parents engagement in risky or unhealthy behaviors either because the parents are spending more time parenting than partying or because they are trying to serve as role models.

Perhaps, and this is likely unmeasurable, it is the “love” in the relationship (and the associated change in neurohormonal milieu) that lowers stress and inflammation and is crucial in stopping atherosclerosis.

Two individuals living together in a committed and loving relationship would seem to have these same factors on their side and I can’t fathom how the legal or religious sanctioning of their union modifies those factors favorably.

Unfortunately, the myriad studies that have been published on this topic totally fail to capture the important distinction between single and unattached and single but living in a committed and loving relationship.

In any event, in the immortal words from my toast to them last night:

“May your fights be short and your apologies many
May your desire to be in each other’s company grow stronger every year
And may all your bartenders look like  Alan Alda”
Here’s to Barb and Dave and marriage and less death!

Urban Cycling Part I: Does Biking To Work Make You More or Less Likely to Die?

5Boro Bike Riders crossing the summit of the Queensboro aka 59th Street aka "Feelin Groovy" Bridge
5Boro Bike Riders crossing the summit of the Queensboro aka 59th Street aka “Feelin Groovy” Bridge. For some reason the significant other of the skeptical cardiologist (SOSC) has decided to stop here to look at her cell phone, thereby creating a traffic hazard.

The skeptical cardiologist recently participated in the 5 Boro New York City Bike Tour. It was quite cool.

This annual event allows 32,000 bike riders to stream from Manhattan to the Bronx to Queens, Brooklyn and Staten Island along 40 miles of traffic-free (except for thousands of cyclists) roads

Unlike my previous rides in Brooklyn and Manhattan (under the guidance of legendary Park Slope flaneur, NYC biking advocate, and old high school chum David Alquist) I was not in constant peril from automobile encounters because we cyclists had the mean streets of New York all to ourselves.

Take a look at this video to understand “why cyclists come from around the world for an experience of the Big Apple unlike any other”.

Urban Cycling as Transportation

The NYC event, and the fact that this is “bike to work week,” lead me to ponder aspects of urban bike riding, specifically, cycling as transportation.  Since cycling is physical exercise and there is scientific evidence (observational studies only) linking regular physical activity to a significant cardiovascular risk reduction, we might expect that it would help us live longer. 

A reasonable physical activity goal , endorsed by most authorities,  is to engage in moderate-intensity aerobic physical activity for a minimum of 30 min on 5 days each week or vigorous-intensity aerobic activity for a minimum of 20 min on 3 days each week. This level of exercise helps with weight control, fitness and is associated with lower mortality from cardiovascular disease .

METS:calories
METs and calories consumed per hour for various physical activities

The metabolic equivalent of task (MET) is a measure of the energy cost of physical activity. The chart to the left gives METs for various activities.  Individuals should be aiming for 500–1,000 MET min/week. Leisure cycling or cycling to work (15 km/hr) has a MET value of 4 and is characterized as a moderate activity  A person shifting from car to bicycle for a daily short distance of 7.5 km would meet the minimum recommendation (7.5 km at 15 km/hr = 30 min) for physical activity in 5 days (4 MET × 30 min × 5 days = 600 MET min/week).

 

Thus, cycling to work for many individuals would provide the daiy physical activity that is recommended for cardiovascular benefits. However, cycling in general, and urban cycling in particular, carries a significant risk of trauma and death from accidents and possibly greater exposure to urban pollutants.

bikversuscardeaths
from CBS (Statistics Netherlands) Traffic and Transport, 2008

This table shows the estimated numbers of traffic deaths per age category per billion passenger kilometers traveled by bicycle and by car (driver and passenger) in the Netherlands for 2008. These data suggest that there are about 5.5 times more traffic deaths per kilometer traveled by bicycle than by car for all ages. Interestingly, there is no increase in risk for individuals aged 15-30 years. On the other hand , those of us in the “baby-boomer” generation (?slowed reflexes, poor eyesight, impaired hearing) and older are at an 8 to 17 fold increase risk.

In the Netherlands, where a very large percentage of the population regularly rides bikes, there has been considerable scientific study of the overall health consequences of biking and we have reasonably good data on the question of relative safety of biking versus driving a car for short distances. You can watch the happy people of Groningen (“the world’s cycling city”, where 57% of the journeys in the city are made by bicycle) riding their bikes below.

Health Impact of Transition from Car to Bike for Short Trips

One study quantified the impact on all-cause mortality if 500,000  people made a  transition from car to bicycle for short trips on a daily basis in the Netherlands and concluded

For individuals who shift from car to bicycle, we estimated that beneficial effects of increased physical activity are substantially larger (3–14 months gained) than the potential mortality effect of increased inhaled air pollution doses (0.8–40 days lost) and the increase in traffic accidents (5–9 days lost). Societal benefits are even larger because of a modest reduction in air pollution and greenhouse gas emissions and traffic accidents.

Apart from the highest average distance cycled per person, the Netherlands is also one of the safest countries in terms of fatal traffic accidents so it’s reasonable to ask whether these data apply to other countries. This study concluded

 When  traffic accident calculations for the United Kingdom were utilized, where the risk of dying per 100 million km for a cyclist is about 2.5 times higher, the overall benefits of cycling were still 7 times larger than the risks.

If you decide to bike to work this week, braving the elements , the possible automobile collisions and the automobile exhaust you can rest comfortably with the thought that not only are you  prolonging your own life but by reducing greenhouse gas emissions and air pollution you are contributing to the health of everyone around you.

What are the Reasons for Lower Heart Attack Risk in the US Virgin Islands?

The skeptical cardiologist was hard at work researching cardiovascular disease in the Virgin islands last week. It was a tough assignment, but I felt I was the right man for the job. It required me to leave the snow and freezing temperatures of St. Louis to fly to St. John where the daytime highs are 82 and the nighttime lows are 73 and the skies are clear to partly cloudy every day.

Honeymoon Beach, St. John, USVI, Virgin Islands National Park
Honeymoon Beach, St. John, USVI, Virgin Islands National Park

The United States Virgin Islands (USVI) are located 1100 miles southeast of Miami and cover 346 square miles, with an estimated population  of 112,000 residents, who live primarily on three islands: St. Croix, St. Thomas, and St. John. About 78 percent of the residents are Black (African-Caribbean), 10 percent White, and 12 percent “other.”  Just under half (49 percent) of the population was born in the Virgin Islands. Native born or naturalized Virgin Islanders are U.S. citizens.

Interestingly, the CDC has reported that the USVI has the lowest rate of heart attack (2.1%) of any state or territory in the US. (W. VA is highest at 6.4%). In addition, a recent study, has shown that blacks in the USVI have a significantly lower rate of cardiovascular disease than blacks in the other 50 states.

Using my cardiology sleuthing skills on site in several Cruz Bay bars and at various beaches and hiking trails I have come up with several hypotheses for the remarkably low rate of cardiovascular disease in this area.

1. Rum-based beverage consumption. Rum is big business in the USVI. As the result of a public-private partnership deal in 2009 the USVI helped Captain Morgan Rum move their distillery from Puerto Rico to St. Croix and helped expand and improve the Cruzan Rum distillery on the islands. As part of the deal the US Congress gives money from excise taxes back to the USVI

The “cover-over” program returns $10.50 of the total $13.50 distilled spirits tax collected per proof gallon to the territories. In 1999, Congress temporarily increased the “cover-over” rate to $13.25 and has extended that rate ever since when it comes up for a bi-annual vote. As part of the agreements with Diageo and Fortune, the USVI government will return a portion of the cover-over funds to the companies in the form of the marketing support, financing of the new or expanded distilleries and waste water treatment facilities, tax incentives and molasses support so companies can secure the key rum ingredient molasses at a competitive price.”

This must explain why rum-based drinks are incredibly cheap in St John. The skeptical cardiologist and the significant other of the skeptical cardiologist (SOSC) found, during the course of their research, that at many beachfront bars, multiple rum-based drinks such as Dark and Stormy’s, Painkillers, and Rum Punches were priced at 3$ during happy hour. Happy hours extended for particularly long hours.

It is well known that alcohol in general raises the good cholesterol, HDL, and lowers cardiovascular disease when consumed in moderation. But could rum have a special cardioprotective effect? More studies are clearly needed in this area.

North Shore Beaches, St. John, Virgin Islands National Park
North Shore Beaches, St. John, Virgin Islands National Park

2.Incredibly beautiful weather, beaches and topography. Our extensive investigations led us to detailed examinations of Solomon, Honeymoon, Caneel, Trunk, Cinnamon, Gibney, Jumbie, and Salt Pond Bay beaches on St. John At these beaches we found that the clear, warm, aquamarine waters with coral reefs close to shore allowed for excellent snorkeling, thus promoting extensive physical activity. Similarly, multiple hiking trails in the  Virgin Islands National park (which covers two-thirds of St. John), stimulated the desire to walk. Physical activity is known to substantially reduce the risk of cardiovascular disease. Could increased physical activity related to a conducive environment be playing a role here?

3.Sun exposure. Some studies suggest a role of low Vitamin D levels in promoting heart attacks. Vitamin D deficiency links to cardiovascular disease can be found in a number of studies demonstrating a 30% to 50% higher cardiovascular morbidity and mortality associated with reduced sun exposure caused by changes in season or latitude. Conversely, the lowest rates of heart disease are found in the sun-drenched Mediterranean coast and in southern versus northern European countries. Cardiac death has been reported to be the highest during winter months.

Is increased sun exposure responsible for the lower heart attack risk on the Virgin Islands?

4.Diet. Our research took us to several restaurants in Cruz Bay, however, I don’t feel that we got a good feel for the typical diet of the people of USVI. The only restaurant that was not owned and operated by rich white people and frequented by predominantly rich white people was an overpriced BBQ joint. The food did not seem different from what one could easily get in a modestly sized mainland city.

5. Relaxed Lifestyle. Epidemiological data show that chronic stress predicts the occurrence of coronary heart disease (CHD). Employees who experience work-related stress and individuals who are socially isolated or lonely have an increased risk of a first CHD event. In addition, short-term emotional stress can act as a trigger of cardiac events among individuals with advanced atherosclerosis. Could the laid back life style in the Caribbean where every one seems to be on “island time” be a factor?

Clearly more research is needed into this topic. Rest assured, the skeptical cardiologist and SOSC will be actively investigating these potentially life changing issues in more detail next winter.