All posts by Dr. AnthonyP

Cardiologist, blogger, musician

“Should You Get A Routine Annual Electrocardiogram?”, Revisited

Four years ago the skeptical cardiologist wrote a post which outlined the reasons why most people should avoid getting a routine annual electrocardiogram.

I pointed out that

If you …feel fine (meaning without symptoms or asymptomatic), exercise regularly, have never had heart problems,  and have a pulse between 60 and 90, the value of the routine annual ECG is very questionable. In fact, the United States Preventive Services Task Force (USPFTF)

“recommends against screening with resting or exercise electrocardiography (ECG) for the prediction of coronary heart disease (CHD) events in asymptomatic adults at low risk for CHD events”

(for asymptomatic adults at intermediate or high risk for CHD they deem the evidence insufficient). The USPSTF feels that that the evidence only supports an annual BP screen along with measurement of weight and a PAP smear.

Yesterday, the USPSTF published an updated analysis which confirmed this recommendation:

The U.S. Preventive Services Task Force (USPSTF) recommends against preventative screening with resting or exercise electrocardiography (ECG) in asymptomatic adults at low risk of cardiovascular disease events in an updated recommendation statement published June 12 in the Journal of the American Medical Association (JAMA).

I should point out that I still believe (although some would disagree) screening for atrial fibrillation with methods other than a 12-lead ECG (including taking the pulse or checking a single lead ECG with a Kardia device) is worthwhile.

Below, I’ve reposted relevant sections of my 2014 post which emphasizes the problem of false positives and false negatives which are quite frequent with any screening test but are particularly worrisome with the routine 12-lead ECG.

 


To many, this seems counter-intuitive: how can a totally benign test that has the potential to detect early heart disease or abnormal rhythms not be beneficial?

There is a growing movement calling for restraint and careful analysis of the value of all testing that is done in medicine. Screening tests, in particular are coming under scrutiny.
Even the annual mammogram, considered by most to be an essential tool in the fight against breast cancer, is now being questioned.

My former cardiology partner, Dr. John Mandrola, who writes the excellent blog at http://www.drjohnm.org, has started an excellent discussion of a recent paper that shows no reduction of mortality with the annual mammogram. He looks at the topic in the context of patient/doctor perception that “doing something” is always better than doing nothing, and the problem of “over-testing.”

In my field of cardiology there is much testing done. It ranges from the (seemingly) benign and (relatively) inexpensive electrocardiogram to the invasive and potentially deadly cardiac catheterization. For the most part, if patients don’t have to pay too much, they won’t question the indication for the tests we cardiologists order. After all, they want to do as much as possible to prevent themselves  from dropping dead from a heart attack and they reason that the more testing that is done, the better, in that regard.

The Problem of False Positives and False Negatives

But all testing has the potential for adverse consequences because of the problem of false positives and negatives. To give just one example: ECGs in people with totally normal hearts are regularly interpreted as showing a prior heart attack. This is a false positive. The test is positive (abnormal) but the person does not have the disease.

12 lead ECG routinely performed prior to surgery and interpreted by computer as ASMI or anteroseptal myocardial infarction ( heart attack).Patient with totally normal heart. Often such false positives are due to poor placement of the ECG leads

False positives lead to unnecessary worry, anxiety, and testing. More testing is highly likely to be ordered; specifically, a stress test. Stress tests in low risk, asymptomatic individuals often result in false positive results. After a false positive stress test, it is highly likely that a catheterization will be ordered. This test carries potential risks of kidney failure, heart attack, stroke and death. It is bad enough that the cascade of testing initiated by an abnormal, false positive,  screening test results in unnecessary radiation, expense and bother but  in some cases it end up killing patients rather than saving lives.

On the other end of the spectrum is the false negative ECG. Most of my patients believe that if their ECG is normal then their heart is OK. Unfortunately the ECG is very insensitive to cardiac problems that are not related to the rhythm of the heart or an acute heart attack.

Patients who have 90% blockage of all 3 of their major coronary arteries and are at high risk for heart attack often have a totally normal ECG. This is a false negative. The patient has the disease (coronary artery disease), but the test is normal. In this situation the patient may be falsely reassured that everything is fine with their heart. The next day when they start experiencing chest pain from an acute heart attack, they may dismiss it as heart burn instead of going to the ER.

More and more, screening tests like the ECG and the mammogram  are rightfully being questioned by patients and payers. For a more extensive discussion about which tests in medicine are appropriate check out the American Board of Internal Medicine’s http://www.choosingwisely.org.

Keep in mind: not uncommonly,  doing more testing can result in worse outcomes than doing less.

Skeptically Yours,

-ACP

h/t Jerry , the life coach of the skeptical cardiologist , who originally posed this question to me.

 

Dr. P’s Heart Nuts and The Flawed But Still Relevant PREDIMED Trial

The skeptical cardiologist was somewhat disheartened to read  the New York Times headline today that the  PREDIMED study was flawed. I frequently reference this landmark randomized trial of the mediterranean diet when I’m citing the cardiovascular benefits of nuts and EV olive oil.

Science mag summarizes the problem which prompted a re-analysis of the study:

A months-long inquiry by the Spanish researchers and NEJM staff uncovered that up to 1588 people in the trial hadn’t been properly randomized: Some were assigned to the same diet as someone else in their household (a common feature of diet studies, but not reported in the original paper). Others, who lived in a rural area, were assigned to different diets based on the clinic closest to them—for example, one group had to pick up a liter of olive oil each week. “The investigator realized he couldn’t get people to travel as far as they needed so he made his study ‘cluster randomized,’” by clinic rather than by individual, Drazen says.

The authors reanalyzed their data without those 1588 participants and found that despite the missteps, the conclusion held: Nuts, olive oil, and fatty fish remained a net positive on heart health, though the conclusions came with somewhat less statistical oomph than in the original paper.

Here’s what I wrote about nuts and the PREDIMED study when I first started distributing Dr. P’s Heart Nuts to my patients.

The skeptical cardiologist has finally prepared Dr. P’s Heart Nuts for distribution. IMG_8339The major stumbling block in preparing them was finding almonds which were raw (see here), but not gassed with proplyene oxide (see here), and which did not contain potentially toxic levels of cyanide (see here).

During this search I learned a lot about almonds and cyanide toxicity, and ended up using raw organic almonds from nuts.com, which come from Spain.

I’ll be giving out these packets (containing 15 grams of almonds, 15 grams of hazelnuts and 30 grams of walnuts) to my patients because there is really good scientific evidence that consuming 1/2 packet of these per day will reduce their risk of dying from heart attacks, strokes, and cancer.

IMG_7965The exact components are based on the landmark randomized trial of the Mediterranean diet, enhanced by either extra-virgin olive oil or nuts (PREDIMED, in which participants in the two Mediterranean-diet groups received either extra-virgin olive oil (approximately 1 liter per week) or 30g of mixed nuts per day (15g of walnuts, 7.5g of hazelnuts, and 7.5g of almonds) at no cost, and those in the control group received small nonfood gifts).

After 5 years, those on the Mediterranean diet had about a 30% lower rate of heart attack, stroke or cardiovascular death than the control group.

It’s fantastic to have a randomized trial (the strongest form of scientific evidence) supporting nuts, as it buttresses consistent (weaker, but easier to obtain), observational data.

Despite the statistical flaws PREDIMED is still an important study demonstrating the benefits of nuts.  PREDIMED was the best randomized trial data we had for nuts but there are tons of observational data which are very consistent and show a strong association between increased nut consumption and reduced mortality..

Consequently, I made up a new batch of Dr. P’s Heart Nuts in honor of the survival of PREDIMED and will be distributing them to patients today.

Meditativeterraneanly Yours,

-ACP

And You May Ask Yourself: Why is David Byrne So Awesome?

The skeptical cardiologist was a second year medical student when the Talking Heads released their debut album, Talking Heads 77. Along with Elvis Costello and The Clash, the Talking Heads kept my spirit alive between crushing sessions of memorizing microbiologic, biochemical and anatomic minutiae.

The band went on to a very successful and highly influential career. I followed them closely through 1985’s commercially successful album, Little Creatures, which features two of my favorite songs from the mid to late 1980s “And She Was” and “Road To Nowhere.”

 

David Byrne, the idiosyncratic songwriter and frontman for the
Talking Heads, is currently on a concert tour in support of his solo album American Utopia  

We caught his performance in St. Louis at the Peabody Opera House Friday night and I have one word to describe it: awesome!

Daniel Durcholz’s review for the St. Louis Post-Dispatch did a much better job of summing it up than I could. He wrote:

I’m impressed with the back strength of the keyboard player (upper right). To dance/walk with (I’m guessing) a 61 key synthesizer and play at the same time seems quite difficult.

an eye-popping, mind-blowing concert that was achieved without the aid of props, video screens, or even a conventional stage set. Byrne’s 11-piece band — each of them clad in a gray suit and barefoot, like Byrne himself — carried their instruments like members of a marching band, allowing them to dance and assemble in various formations.

Beaded curtains lined the sides and back of the stage, forming a boxlike space that the musicians could perform within, effortlessly exiting and entering as needed.

Several songs featured a bright light source mysteriously moving around the stage, casting gigantic, fascinating shadows. That is Byrne front and center with guitar. Sitting in the balcony gave good views of the three-dimensional movement and positioning of the players

The overall look and feel of the show was hyper-theatrical, yet utterly human at its core. There were no backing tracks, Byrne emphasized at one point. “Everything you hear is being played by these incredible musicians,” he said.

No stranger to innovation, Byrne reinvented the concert experience in the Talking Heads’ 1984 film “Stop Making Sense.” This current outing is, if anything, even more radical and engaging.

Stop Making Sense is considered by many to be the greatest concert film of all time ((although I’m sure the eternal fiancee’ would place The Last Waltz above SMS) )but I think a Jonathan Demme or Martin Scorcese film of David Byrne’s current concerts might claim that honor.

Until such film is released this performance of “Everybody’s Coming to My House” (arguably the best song on his new album) by Byrne and his band on The Late Show With Stephen Colbert will have to suffice.

The information available through the internet never ceases to amaze me. You can click here to see exactly what Byrne played Friday night complete with links to the songs and/or videos of the songs.

If you click on the 9th song on the setlist you will be taken to this iconic existential video:

So, if you ever liked the Talking Heads or just love good music try to catch David Byrne’s show..

You might find yourself singing along with him as the audience did last Friday night the following words:

And you may find yourself
Living in a shotgun shack
And you may find yourself
In another part of the world
And you may find yourself
Behind the wheel of a large automobile
And you may find yourself in a beautiful house
With a beautiful wife
And you may ask yourself, well
How did I get here?

And you may find yourself asking “Why is David Byrne so Awesome?”

Letting the days go By,

-ACP

h/t Lauren at http://www.allezgourmet.com for alerting me to Byrne’s St. Louis concert.

Which Exercise Is Best For Heart Health: Swimming or Walking?

Reader Pat asked the skeptical cardiologist the following question:

Which would be the better heart healthy choice? Walking briskly 3 x week or swimming for 45 minutes 2-3 x a week?

Swimming is an attractive alternative to walking or running for many of my patients with arthritis because it is a lot easier on the load-bearing joints of the lower extremities.

To my surprise there is at least one study (from Australia) comparing swimming and walking that was published in the journal Metabolism in 2010.

The investigators randomly assigned 116 sedentary women aged 50-70 years to swimming or walking. Participants completed 3 sessions per week of moderate-intensity exercise under supervision for 6 months then unsupervised for 6 months.

Compared with walking, swimming improved body weight, body fat distribution and insulin resistance in the short term (6 months).

At 12 months swimmers had lost 1.1 kg more than walkers and had lower bad cholesterol levels.

It should be noted that these differences barely reached significance .

Types of Activities And The Intensity of Exercise

My general recommendations on exercise (see here) give examples of different aerobic physical activities and intensities.

These activities are considered Moderate Intensity

  • Walking briskly (3 miles per hour or faster, but not race-walking)
  • Water aerobics
  • Bicycling slower than 10 miles per hour
  • Tennis (doubles)
  • Ballroom dancing
  • General gardening Vigorous Intensity

These types of exercise are considered Vigorous Exercise

  • Racewalking, jogging, or running
  • Swimming laps
  • Tennis (singles)
  • Aerobic dancing
  • Bicycling 10 miles per hour or faster
  • Jumping rope
  • Heavy gardening (continuous digging or hoeing, with heart rate increases)
  • Hiking uphill or with a heavy backpack

As a rule of thumb, consider 1 minute of vigorous exercise equivalent to 2 minutes of moderate exercise and shoot for 150 minutes per week of moderate exercise or 75 minutes of vigorous exercise.

Of course one can swim laps at peak intensity or at a very slow, leisurely pace so swimming laps doesn’t always qualify as “vigorous” exercise. Likewise one can play singles tennis languorously and be at a moderate or lower intensity of exercise.

It is entirely possible that the swimmers were working at a higher intensity during their sessions than the walkers and that could be the explanation for the differences seen between the two groups.

Ultimately, the best type of  exercise for heart health is the one you can do and  (hopefully) enjoy on a regular basis.

Antilanguorously Yours,

-ACP

N.B. Speaking of swimming. A year ago I wrote about longevity and featured Eugene, a 98 year old who could swim the length of a swimming pool underwater. Eugene turns 100 in 2 days.

Mitigating Sarcopenia In The Elderly: Resistance Training Is A Powerful Potion

While researching afib-detection apps recently, the skeptical cardiologist stumbled across an article with the title “Resistance training – an underutilized drug available in everybody’s medicine cabinet”

This brief post from the British Journal of Sports Medicine blog nicely presents the rationale for using strength training to improve the overall health of the elderly. I have reblogged it below.

Americans spend billions on useless supplements and vitamins in their search for better health but exercise is a superior drug, being free  and without drug-related side effects

I’ve spent a lot of time on this blog emphasizing the importance of aerobic exercise for cardiovascular health but I also am a believer in strength and flexibility training for overall health and longevity.

As we age we suffer more and more from sarcopenia-a gradual decrease in muscle mass.

Scientific reviews note that loss of muscle mass and muscle strengh is quite common in individuals over age 65 and is associated with increased dependence, frailty and mortality

Specific information on progressive resistance training for the elderly is sparse but I found this amusing and helpful video on a Canadian site that provides some guidance for beginners.

 

And below is the referenced blog post:

Resistance training – an underutilised drug available in everybody’s medicine cabinet

By Dr Yorgi Mavros @dryorgimavros

As we get older we begin to lose muscle mass, approximately 1% every year. But more importantly, the decline in muscle strength declines at a rate 3-times greater [1]. The consequences of this decline in strength are significant, with lower muscle strength being associated with an increased risk dementia[2], needing care, and mortality[3]. But should we accept this as our fate, or is there anything we can do prevent, reverse or at least slow this age-related decline?

In 1990, a type of exercise called progressive resistance training, commonly known as strength training, was introduced to 9 nonagenerians living in a nursing home, specifically to treat the loss of muscle mass and strength, and the functional consequences of disability [4]. After just 8 weeks, these older adults saw average strength gains of 174%, with 2 individuals no longer needing a cane to walk. In addition, one out of the three individuals who could not stand from a chair, was now able to stand up independently. Just take a moment to think about the results of that study. If I told you there was a medicine that you or a loved one could take, and it could make either of you strong enough to now get out of a chair, would you take it?

What if you or a loved one had a hip fracture, and I told you that same medicine could help reduce the risk of mortality by 81%, and the risk of going in to a nursing home by 84%, as was shown in this study [5]. Currently, the only way to take this medicine is by lifting weights, or pushing against resistance.

A recent study from Britain, [6] showed an association between adults who participated in 2 days per week of strength training and a 20% reduction in mortality from any cause, and a 43% reduction in cancer mortality. Data from the Women’s Health Study in the US published at a similar time were very similar, with women reporting up to 145 minutes per week of strength training having a 19-27% reduced risk of mortality  from any cause [7].

So where does the benefit of strength training come from? First and foremost, it is anabolic in nature (meaning that it can stimulate muscle growth) making it the only type of exercise that can address the age-associated decline in muscle mass and strength. Within our laboratory at the University of Sydney, we have shown that we can use this type of exercise to improve cognitive function in adults who have subjective complaints about their memory [8]. What’s important though, is that there was a direct relationship between strength gains and improvements in cognition, and so maximizing strength gains should be a key focus if you want to maximize your benefit [9]. This type of exercise has even been taken into hospitals and used in adults with kidney failure undergoing haemodialysis, where it was shown to reduce inflammation, and improve muscle strength and body composition [10].

Other laboratories around the world have also used strength training to increase bone strength in postmenopausal women [11], help manage blood sugar levels in adults with type 2 diabetes [12], as well as to counteract the catabolic side effects of androgen-deprivation therapy for men with prostate cancer [13]. Not to mention its benefits to sleep [14], depression  [15] and recovery from a heart attack  [16].

So it is no surprise to see that the  Australian [17] and UK [18] public health guidelines for physical activity recommend we take part in activities such as strength training 2-to-3 days per week. Unfortunately however, these recommendations lack detail and guidance on intensity and frequency.

A key theme in all the randomized controlled studies discussed above, is that not only were exercises performed at least 2 days per week, but they were fully supervised, used machine and/or free weights, and were done at a high intensity, which is commonly set to 80% of an individual’s peak strength. It is for this reason I like to focus on the guidelines put forward by The American College of Sports Medicine (ACSM) [19]. The ACSM advises that everyone, including older adults do at least 2 days of progressive resistance training, which is to be performed at a moderate (5 – 6) to high/hard (7 – 8) intensity on a scale of 0 to 10, involving the major muscle groups of the body. So if you are looking to maximise the benefit from your time in the gym, or looking to make a positive change to your lifestyle, remember that there is medicine you can take; Try lifting some weights or doing other forms of strength training, 3 days a week, and importantly, make sure it feels moderate to hard. Not only will it add years to your life, but life to your years.


Since college I have regularly done weight training 3 times per week As I get  dangerously close to age 65 and joining the ranks of the “elderly” I have ramped up the intensity of my workouts, working hard to forestall the sarcopenia that will ultimately be my fate.

Antisarcopenically Yours,

-ACP

***************************

Video credit: Produced for the University of British Columbia’s (UBC) Department of Physical Therapy, the Aging, Mobility, and Cognitive Neuroscience Laboratory, the Centre for Hip Health and Mobility and the Brain Research Centre at Vancouver Coastal Health and UBC
hiphealth.ca/news/preventing-dementia

 

Flaxseed: Plant-Based Omega 3 Super Food or Faux Fish Oil?

Ground flaxseed plus Trader’s Point Creamery full fat plain yoghurt. It’s not pretty but tastes pretty good.

The skeptical cardiologist has a confession to make: he’s been adding ground flaxseed to his typical late morning full fat yoghurt plus berries and almonds.

Adding flaxseed seems dangerously close to dietary behaviour I have been advising against: supplementing instead of eating real food.

Also, I am philosophically opposed to going out of my way to eat any edible that is consistently promoted as a “super food” or a “functional food.” To me, these are meaningless terms and marketing blather

When I began writing this post in 2017 I was getting my flaxseed from Stober Farms (Est. 1901) who had been producing “for over 100 years  the finest flax in the world.”  Stober Farms provided me with “organic Golden Flax Seed which has been Cold-Milled Processed.”

Stober Farms (who have since mysteriously gone into bankruptcy) also informed me:

Flax is digested most effectively when ground. Some grinding methods generate heat when milled, spurring early omega-3 oxidation. Stober Farms uses a unique cold-milled process, which gently grinds the seed without significantly raising the temperature. This proprietary method preserves the nutrients, flavor and extends the shelf life to 22 months.

Honestly, I don’t recall exactly why I began “flaxing” but I suspect I felt it was a good way to boost the fat content in my full fat yoghurt (yes, I am now spelling yoghurt with an h) and berries and perhaps sufficiently satiate me that it would be the only food I would need to consume until dinner or late afternoon.

Two tablespoon (14 grams) is what I typically  imprecisely add. These tablespoons provide 75 kcal of energy which comes from 3 grams of protein, 6 grams of fat, and 4 grams of carbs.  Three of the four carb grams are soluble fibre.

About half of the fat in flaxseed is in the form of alpha-linolenic acid (ALA)(18:3) an omega-3 polyunsaturated (PUFA) fat.  Flaxseed oil contains five times more ALA than walnut oil or canola oil, which are the next highest sources of ALA.

Is Flaxseed A Super Functional Food?

Many seemingly authoritative sites on the internet proclaim that flaxseed is incredibly healthy. For example, Healthline.com’s “Authority Nutrition” (they must be authoritative as authority is in their name)  presents their 10 health benefits of eating flaxseed “backed by science”  and concludes:

They can be used to improve digestive health, lower blood pressure and bad cholesterol, reduce the risk of cancer and may benefit people with diabetes.

But typical of  Authority Nutrition’s overblown claims  these are not truly proven by science. The studies cited are weak; typically short-term tests of biomarkers or animal studies or human studies with very small numbers. Most importantly. these studies , which are often funded by flaxseed promoters are highly likely to be biased in favor of positive results.

Most websites tout the cardiovascular benefits of the omega-3 PUFA in flaxseed, the high percentage of soluble fibre and  the benefits of a chemical which cannot be named (due to a name which is too difficult to pronounce), SDG.

Omega-3 PUFAs and fibre I’ve touched on previously (and positively) but what about the mysterious and unpronounceable SDF. Per a 2010 review article

Flaxseed is the richest source of the lignan secoisolariciresinol diglucoside (SDG). After ingestion, SDG is converted to secoisolariciresinol, which is further metabolised to the mammalian lignans enterodiol and enterolactone. A growing body of evidence suggests that SDG metabolites may provide health benefits due to their weak oestrogenic or anti-oestrogenic effects, antioxidant activity, ability to induce phase 2 proteins and/or inhibit the activity of certain enzymes, or by mechanisms yet unidentified.

Like so many putative wonder phytochemicals, SDG has a “growing body of evidence” for lots of things but actual proof that it does anything worthwhile in humans is lacking and awaits  well done randomized clinical trials

Poorly researched articles on flaxseed are highly likely to tout its anti-inflammatory properties. These properties are seen in rats but unfortunately haven’t been proven in my favorite species, Homo Sapiens ,  Flaxseed doesn’t seem to decrease the inflammatory marker CRP in humans as reported in this systematic review and meta-analysis.

ALA and Cardiovascular Disease

As I’ve indicated in previous posts, evidence supports fatty fish consumption as beneficial in reducing cardiovascular disease presumably by increasing levels of marine omega-3 PUFAs in the body.

The value of fish oil supplementation, however, is not proven (see here).

How does ALA compare to the seafood omega 3s  in preventing cardiovascular disease (CVD)?

In 2012, researchers at the Harvard School of Public Health published a systematic review and meta-analysis of the existing data on ALA and the risk of CVD..

Their introductory paragraph nicely lays out why ALA could be very important to public health:

A large body of evidence supports a potential protective effect of seafood omega-3 (n−3) fatty acids, particularly EPA (20:5n−3) and DHA (22:6n−3), on coronary heart disease (CHD. However, fewer studies have evaluated how the plant-derived omega-3 fatty acid α-linolenic acid (ALA; 18:3n−3) relates to risk of CHD and other cardiovascular disease (CVD) outcomes, and the results have been inconsistent As an essential fatty acid that cannot be synthesized by humans, ALA is mainly consumed from plant sources, including soybeans, walnuts, and canola oil. Compared with seafood omega-3 fatty acids, ALA from plant sources is more affordable and widely available globally. Thus, whether ALA can reduce the risk of CVD is of considerable public health importance.

If plant-derived ALA can provide our omage-3 PUFA needs then perhaps we can stop stripping the ocean of all the menhaden.

In the Harvard analysis when all 27 studies were combined the authors found a significant risk reduction of 14% in CVD events with flaxseed.

There were lots of issues with the data which I won’t bore you with leading the authors to conclude that “ALA consumption may be beneficial “.  They emphasized the need for additional well-designed observational studies and randomized clinical trials in the area.

Since observational studies cannot prove causality, I await a good randomized clinical trial of ALA supplementation before I can recommend ALA supplementing to prevent heart disease.

After Performing This Review Is The Skeptical Cardiologist Still “Flaxing”?

I am. Because I’ve found that when I consume flaxseed I feel 20 years younger, full of vitality. and with a youthful golden sheen to my hair, nails and skin.

Actually, that last sentence is untrue.

I’m still adding ground flaxseed to my yoghurt but not with any expectation that it is reducing my risk of heart attack and definitely not because I perceive it as a super or functional food.

I like the taste, the convenience, and the extra (presumably healthy) calories it provides but I’m still an advocate of just eating real food rather than trying to identify specific nutrients, nutraceuticals or supplements and add them to your diet.

Flaxseedingly Yours,

-ACP

N.B. I did not touch on omega-6/omega-3 ratios in the diet. I’ve been examining that inflammatory (enjoy the pun) topic for years and once I come across a good study that adds to understanding in the area I will likely publish a post on it.

 

The Eggsoneration Continues: Why Does Anyone Eat Egg Whites?

The skeptical cardiologist pointed out in 2013 that there was no good evidence supporting limiting dietary cholesterol to 300 mg per day.  I exulted, therefore, in 2016 , when this long-standing dietary recommendation came out of the US dietary guidelines.

Recognizing that dietary cholesterol doesn’t need to be limited means that eggs and egg yolks are fine.

Egg Whites: A Product of Nutritional Misinformation?

Why, then do egg whites continue to be created and consumed?

On a regular basis, patients tell me that they are eating egg white omelettes because they believe egg yolks are not heart healthy.

Old bad nutritional dogma takes a long time to reverse apparently. To this day, for example, the National Lipid Association still recommends limiting daily cholesterol consumption to <200 mg/ day

Therefore I find it necessary to highlight additional new studies that further eggsonerate eggs.

To wit, I shall briefly discuss two articles that were published earlier this month and brought to my attention by friends and readers who are aware of my rabid support for the egg.

Article One: The Wonderfully Acronymed DIABEGG Study

Entitled  “Effect of a high-egg diet on cardiometabolic risk factors in people with type 2 diabetes: the Diabetes and Egg (DIABEGG) Study—randomized weight-loss and follow-up phase” our fist study was performed in Australia at the Sydney Medical School,

Investigators randomized 128 patients with prediabetes or type 2 diabetes (T2D) to a high egg or a low egg diet.

Throughout all study phases, including the 3-mo weight-loss phase, participants consuming the high-egg diet were instructed to eat 2 eggs/d at breakfast for 6 d/wk (12 eggs/wk). Those in the low-egg group were directed to consume <2 eggs/wk, and to match the protein intake that the high-egg group had consumed at breakfast with 10 g lean animal protein (meat, chicken, or sh) or other protein-rich alternatives, such as legumes and reduced-fat dairy products (also consumed at breakfast). Recommended egg-cooking methods were boiled or poached, but they could also be fried if a polyunsaturated cooking oil, such as olive oil, was used. The prescribed diets were energy and macronutrient matched, as reported previously

At the end of 12 months both groups had lost about 3 kg in weight.
The investigators measured everything they could to look at diabetic and cardiometabolic biomarkers which might suggest adverse effects of egg eating on the cardiovascular system but they could find no difference between the egg eaters and the non egg eaters.
High egg consumption had no adverse effects on the following factors that are felt to be important in the development of atherosclerosis:

-measures of systemic and vascular inflammation [high sensitivity C-reactive protein (hs-CRP), IL-6, soluble E-selectin (sE-selectin)],

-oxidative stress (F2-isoprostanes), the adipokine adiponectin (which also modulates insulin resistance), and

-glycemia [fasting plasma glucose, glycated hemoglobin (HbA1c), and a medium-term measure of glycemia, 1,5-anhydroglucitol (1,5AG)].

The authors suggested that nutritional guidelines stop worrying about limiting eggs.

Article Two: Half A Million Chinese Can’t Be Wrong

This observational study published in Heart found that egg consumption in a huge Chinese population was associated with less stroke, and major cardiac events (MCE):

Compared with non-consumers, daily egg consumption was associated with lower risk of CVD (HR 0.89, 95% CI 0.87 to 0.92). Corresponding multivariate-adjusted HRs (95% CI) for IHD, MCE, haemorrhagic stroke and ischaemic stroke were 0.88 (0.84 to 0.93), 0.86 (0.76 to 0.97), 0.74 (0.67 to 0.82) and 0.90 (0.85 to 0.95), respectively. There were significant dose-response relationships of egg consumption with morbidity of all CVD endpoints (P for linear trend <0.05). Daily consumers also had an 18% lower risk of CVD death and a 28% lower risk of haemorrhagic stroke death compared to non-consumers.

The lower risk for stroke and cardiovascular death in egg eaters persisted after accounting for known CVD risk factors.

(And yes, I agree this is an observational study which we should take with huge grains of salt and pepper).

Are EGG Whites The Skim Milk Scam of The Egg Industry?

I’ve written about the scam that is skim milk but it occurs to me that egg white consumption is equally nonsensical.

What happens to the wonderfully nutritious yolk of the egg when it is brutally separated from its white? It is put in a container and sold as  liquid egg yolk. Makers of mayonnaise are big consumers of liquid egg yolk.

Thus, like dairy farmers who double their sales by selling skim milk and its dairy fat separately, egg producers are probably delighted that Americans are consuming egg whites , allowing them to get two products from a single egg.

As I wrote previously: not everyone is an egg lover and I’m fine with that. There is no evidence that you have to eat them. You could feel towards them as did Alfred Hitchcock :

“I’m frightened of eggs, worse than frightened, they revolt me. That white round thing without any holes … have you ever seen anything more revolting than an egg yolk breaking and spilling its yellow liquid? Blood is jolly, red. But egg yolk is yellow, revolting. I’ve never tasted it.”

For those that don’t find yellow revolting, however, avoiding egg yolk makes no nutritional sense.

Eggsplicatively Yours,

-ACP

Heart Attacks and E-cigarettes: Are America’s Teens Putting Themselves At Risk?

Many of the skeptical cardiologist’s patients managed to quit cigarette smoking by using e-cigarettes . They often continue to vape, prolonging their addiction to nicotine but overall I felt they were probably better off than smoking cigarettes. However,  a couple of recent articles have me very concerned about the overall effect of e-cigarettes on public health.

The first article came from the PR department at  UCSF with the headline:

Smoking E-Cigarettes Daily, Doubles Risk Of Heart Attacks”

It focused on an abstract presented in Baltimore in February 2018 by Stanton Glantz, UCSF professor of medicine and director of the UCSF Center for Tobacco Control Research and Education. The abstract (paper yet to be published) was an observational study of about 70,000 individuals. Since it was observational the causality implied by the headline is not justified but the findings are still worrisome:

When adjusted for other risk factors, daily e-cigarette use was associated with significantly increased odds (Odds Ratio: 1.79) of having had a heart attack (myocardial infarction), as was daily conventional cigarette smoking (OR: 2.72). Former and occasional e-cigarette use were not associated with significant changes in the odds of having had a heart attack, while the same categories of cigarette smoking were associated with smaller increases in risk than for current smokers.

So e-cigarettes might be safer than real cigarettes but if you don’t quit smoking you are worse off:

“E-cigarettes are widely promoted as a smoking cessation aid, but for most people, they actually make it harder to quit smoking, so most people end up as so-called ‘dual users’ who keep smoking while using e-cigarettes,” said Glantz. “The new study shows that the risks compound. Someone who continues to smoke daily while using e-cigarettes daily has an increased risk of a heart attack by a factor of five.

Juul and The Rise In Teenage Vaping

The second article was from The New Yorker and is fascinating. Entitled “The Promise of Vaping and the Rise of Juul.” ,  it details an alarming rise in teenage vaping which often involves a particular brand of e-cigarette, Juul,  which resembles a flash drive.

Screen Shot 2018-05-22 at 12.13.01 PM
“Smoking is gross,” a high schooler said. “Juuling is really what’s up.”Photograph by Elizabeth Renstrom for The New Yorker

To Juul (the brand has become a verb) is to inhale nicotine free from the seductively disgusting accoutrements of a cigarette: the tar, the carbon monoxide, the garbage mouth, the smell. It’s an uncanny simulacrum of smoking. An analyst at Wells Fargo projects that this year the American vaporizer market will grow to five and a half billion dollars, an increase of more than twenty-five per cent from 2017. In the latest data, sixty per cent of that market belongs to Juul.

Scientists Warn of E-cigarette Health Risks 

In March, a congressionally mandated report on the health effects of e-cigarettes  from the National Academies of Sciences, Engineering, and Medicine concluded:

Evidence suggests that while e-cigarettes are not without health risks, they are likely to be far less harmful than conventional cigarettes, the report says. They contain fewer numbers and lower levels of toxic substances than conventional cigarettes, and using e-cigarettes may help adults who smoke conventional cigarettes quit smoking.

With respect to cardiovascular diseases, their conclusions were:

  1. We don’t currently have evidence that e-cigarettes increase risk of stroke or heart attack or subclinical atherosclerosis
  2. There is good evidence that in the short term the nicotine in e-cigarettes raises systolic and diastolic blood pressure and heart rate
  3. There is limited evidence that e-cigarettes increase biomarkers of oxidative stress, increase endothelial dysfunction and arterial stiffness. All of these factors are known to contribute to the development of atherosclerosis.

Long term, it is anyone’s guess what the consequences of vaping on the cardiovascular system will be.

As the New Yorker article makes abundantly clear, however, the youth of America are taking up vaping and Juuling increasingly and the National Academies are appropriately worried:

However, their long-term health effects are not yet clear. Among youth — who use e-cigarettes at higher rates than adults do — there is substantial evidence that e-cigarette use increases the risk of transitioning to smoking conventional cigarettes

Are Your Kids Vaping?

In 2015 there was a 40% chance your middle school or high school child had used e-cigarettes. The chart below from the CDC shows how rapidly rates are climbing.

The surgeon general/CDC issued a warning in 2016, writing:

E-cigarette use among U.S. youth and young adults is now a major public health concern. E-cigarette use has increased considerably in recent years, growing an astounding 900% among high school students from 2011 to 2015. These products are now the most commonly used form of tobacco among youth in the United States, surpassing conventional tobacco products, including cigarettes, cigars, chewing tobacco, and hookahs. Most e-cigarettes contain nicotine, which can cause addiction and can harm the developing adolescent brain.

Compared with older adults, the brain of youth and young adults is more vulnerable to the nega- tive consequences of nicotine exposure. The effects include addiction, priming for use of other addic- tive substances, reduced impulse control, deficits in attention and cognition, and mood disorders. Furthermore, fetal exposure to nicotine during pregnancy can result in multiple adverse consequences, including sudden infant death syndrome, altered corpus callosum, auditory processing deficits, effects on behaviors and obesity, and deficits in attention and cognition. Ingestion of e-cigarette liquids con- taining nicotine can also cause acute toxicity and possibly death if the contents of refill cartridges or bottles containing nicotine are consumed.

Stealth Vaping Devices

Vaping devices no longer clearly look like cigarettes. Here are some examples from the CDC report.

 

 

 

 

 

 

 

 

Note, however, that the Juul is not depicted.

By Mylesclark96 [CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0)%5D, from Wikimedia Commons
It doesn’t look like a cigarette or a device that would be facilitating your child’s addiction to nicotine. And it has a USB port so it can be recharged from a laptop.

 

 

This wasn’t an issue as far as I can tell when my children were teens but I’m pretty sure if I had teenagers I would ban vaping and would confiscate anything that resembled an e-cigarette including  flash or thumb drives that aren’t flash or thumb drives.

Skeptically Yours,

-ACP

US Health Care: Spending More But Getting Less Than Peer Countries Since 1980

Austin Frackt has a good article up at The incidental Economist discussing this graph:

life-spend

Why did the US become such an outlier; spending lots more per capita on health care but without demonstrable benefit?

A second graph shows how US longevity has not kept up with improvements noted in peer countrieslife-expectancy-1.jpg

Frakt touches on many of the proposed mechanisms for America’s divergence from the pack and the article is well worth a few minutes of your time.

Skeptically Yours,

-ACP

 

What You Should Know About Lipoprotein(a) And Heart Attack Risk

If you have had a heart attack at an early age or one of your parents did but your standard risk factors for coronary heart disease are normal you should consider getting tested for Lipoprotein(a) or Lp(a).

The standard lipid profile that most patients get checks LDL (bad) HDL (good) and total cholesterol along with  triglycerides. While these are useful, I have many patients who have normal standard values but have developed advanced coronary heart disease at an early age despite following a perfect lifestyle (not smoking, regular aerobic exercise, healthy diet.)

The skeptical cardiologist tests such patients for Lp(a) (pronounced LP little a)  and it is quite frequently elevated.

For patients, these are the facts to know about Lp(a)

  1. It is the strongest single inherited (monogenetic) risk factor for the early development of coronary artery disease, heart attacks and strokes.
  2. In addition to increasing risk of atherosclerosis, high Lp(a) is strongly associated with the development of calcific aortic valve disease which can result in narrowing of the aortic valve and aortic stenosis.
  3. Depending on the cut-off used  up to one in five individuals may have elevated Lp(a)
  4. Levels of Lp(a) can be measured with a simple blood test that should cost no more than 50 to 100$. This is not included in standard lipid or cholesterol testing.
  5. Risk for heart attack starts to rise with levels above 30 mg/dl and Canadian guidelines from 2016 (see here)) consider >30 mg/dl to be a risk factor and they recommend measuring Lp(a) in those with a family history of premature CAD or those at intermediate risk.
  6. The European Atherosclerosis Society (EAS, 2010), suggested levels of <50 mg/dl as optimal. The EAS advised measuring Lp(a) once in all patients with premature CVD.
  7. As levels get even higher risk also rises as these graphs show

 

 

 

 

Treatment For High Lp(a)

The lifestyle changes (both exercise and diet) that improve bad and good cholesterol levels have no effect on Lp(a). Our best drugs, the statins, for reducing risk of heart attack and stroke also don’t lower Lp(a) levels.

Only niacin has been shown to reduce Lp(a) across broad populations but there is no evidence that Lp(a) lowering by niacin lowers cardiovascular risk so it cannot be recommended for treatment.(In the AIM-HIGH study niacin did not reduce cardiovascular events in patients with Lp(a) with levels>50 mg/dl, despite achieving a mean Lp(a) reduction of 39%.)

Cholesteryl ester transfer protein inhibitors which raise HDL levels also reduce lipoprotein(a) concentrations, but three such inhibitors have not shown a clinical benefit.

In fact, currently there are no studies showing that lowering Lp(a) with any drug will effectively lower the associated risk of heart attack, stroke and aortic stenosis.

In the not too distant future, effective therapies may emerge. There are promising newer agents (antisense oligonucleotides or ASOs) currently in clinical trials and in limited populations the PCSK9 inhbitors, mipomersen and estrogen have lowered Lp(a) levels.

Why Test For Lp(a)?

If we have no effective therapies that work by lowering Lp(a) why recommend testing for it?

I test Lp(a) for  two reasons.

First, since it is inherited, patients with high levels should consider having first degree relatives tested for Lp(a) to identify those who are going to be at high risk. This provides an early warning of who in the family is most at risk for cardiovascular complications early in life. Such patients should be considered for early screening for subclinical atherosclerosis. In addition, they should be additionally motivated to do everything possible to reduce their elevated risk by lifestyle changes.

Second, I tend to recommend  more aggressive cholesterol lowering in patients who have evidence for early plaque build up for atherosclerotic events early in life than I otherwise would be.     I tend to agree with the approach diagrammed below:

 

With this approach for patients who have had events related to atherosclerosis or advanced CAC for age we work super aggressively on optimizing all risk factors. I try to lower LDL to <70 with statins and with the addition of ezetimibe or PCSK9 inhbitors if needed.

If the patient has more problems with atherosclerotic events despite optimizing risk factors and Lp(a) >60 mg/dl, some experts recommend using apheresis a technique which runs the patient’s blood through a filter which removes LDL and Lp(a). Personally, I have not sent any patients for apheresis and await better studies proving its benefit.

Antiproatherogenically Yours,

-ACP

For those patients seeking more detailed information and references I recommend Dr. Siggurdson’s excellent post on Lp(a)

There is a Lipoprotein(a) Foundation with reasonably informative and accurate website you can peruse here for more information.

Finally, if you want to delve deeply into the data check out this recent JACC review here.

The graphs above and this figure
showing the proposed pro-inflammatory, pro-atherogenic and pro-thrombotic pathways of Lp(a) are from that article.