Tag Archives: heart attack

Should You Reduce Saturated Fat Consumption If You Have Heart Disease?

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Most heart attacks occur in folks with pre-existing coronary artery disease that’s been present for years

For the bulk of my medical career, physicians thought that saturated fat caused heart disease, specifically coronary artery disease and heart attacks. Most doctors still think that. In 2009, I spent 80 hours reviewing the scientific literature supporting the saturated fat/heart disease connection. The evidence was very weak, if not nonexistent.

But what if you are already a heart disease patient? Would continuing saturated fat consumption have any effect on your longevity and risk of future heart attacks? If you already have coronary artery disease, Dr. Axel Sigurdsson says that ongoing saturated fat intake probably doesn’t matter, in terms of future cardiac events (like heart attacks) or risk of death from any cause.

Dr. Sigurdsson is a cardiologist in Iceland.

Some quotes from his blog:

For decades, cardiologists have advised patients with heart disease to restrict the intake of saturated fats and dietary cholesterol. Many patients still believe this to be the cornerstone of their lifestyle modification.

The main reason for avoiding saturated fats is the assumption that they adversely affect the lipid profile of our patients.

*   *   *

Recent studies suggest that the recommendation to avoid saturated fats may have been premature and not based on solid scientific evidence.

Now, a recently published Norwegian study shows that dietary intake of saturated fatty acids was not associated with risk of future events or death among patients with established coronary artery disease.

It is important to keep in mind that most of the patients were receiving secondary prevention drug therapy including aspirin, beta blockers and statins.

Anyhow, the results of the study certainly suggest that high intake of saturated fats is not a risk factor among patients with coronary heart disease receiving modern-day treatment.

These recent scientific data don’t imply that we should urge our patients to consume high amounts of saturated fats. They only tell us that there is no association and accordingly, restriction won’t help.

So, it’s certainly a lifeline for those who believe red meat, whole-fat milk, cheese, cream, butter and eggs can be a part of a healthy diet.

On the other hand we must realise that scientific studies often provide contradictory results. A US study published last year suggested that greater adherence to a low carbohydrate diet high in animal sources of fat and protein was associated with higher all-cause and cardiovascular mortality following acute heart attack.

It appears the jury is still out…

RTWT.

Steve Parker, M.D.

7 Comments

Filed under Fat in Diet, Heart Disease

Worried About Future Heart Attack? Check Your LDL Cholesterol Particle Number (LDL-P)

…according to Drs. Thomas Dayspring and James Underberg. I don’t know if these guys are right or not. I bet it’s more complicated than simple LDL particle number.

Even if you eat lots of eggs, most of your cholesterol is made by your liver. That's where statin drugs work.

Even if you eat lots of eggs, most of your cholesterol is made by your liver. That’s where statin drugs work.

Most heart attacks (aka myocardial infarctions) do indeed seem to be caused by acute rupture of an atherosclerotic plaque that’s been present for years. Two key questions are:

  1. What causes the plaque?
  2. Why causes them to rupture?

Underberg and Dayspring write:

The only absolute requirement for plaque development is the presence of cholesterol in the artery: although there are additional heart risk factors like smoking, hypertension, obesity, family history, diabetes, kidney disease, etc., none of those need to be present. Unfortunately, measuring cholesterol in the blood, where it cannot cause plaque, until recently has been the standard of risk-testing. That belief was erroneous and we now have much better biomarkers to use for CV risk-assessment. The graveyard and coronary care units are filled with individuals whose pre-death cholesterol levels were perfect. We now understand that the major way cholesterol gets into the arteries is as a passenger, in protein-enwrapped particles, called lipoproteins.

Particle entry into the artery wall is driven by the amount of particles (particle number) not by how much cholesterol they contain. Coronary heart disease is very often found in those with normal total or LDL-cholesterol (LDL-C) levels in the presence of a high LDL particle number (LDL-P). By far, the most common underlying condition that increases LDL particle concentration is insulin resistance, or prediabetes, a state where the body actually resists the action of the sugar controlling hormone insulin. This is the most common scenario where patients have significant heart attack risk with perfectly normal cholesterol levels. The good news is that we can easily fix this, sometimes without medication. The key to understanding how comes with the knowledge that the driving forces are dietary carbohydrates, especially fructose and high-fructose corn syrup. In the past, we’ve often been told that elimination of saturated fats from the diet would help solve the problem. That was bad advice. The fact is that until those predisposed to insulin resistance drastically reduce their carbohydrate intake, sudden deaths from coronary heart disease and the exploding diabetes epidemic will continue to prematurely kill those so afflicted.

***

And for goodness’ sake, if you want to live longer, start reducing the amount of dietary carbohydrates, including bread, potatoes, rice, soda and sweetened beverages (including fruit juices), cereal, candy – the list is large).

Underberg and Dayspring don’t mention don’t mention LDL particle size, such as small/dense and large/fluffy; the former are thought by many to be much more highly atherogenic. Is that outdated?

Whoever figures out the immediate cause of plaque rupture and how to reliably prevent it will win a Nobel Prize in Medicine.

Read the whole enchilada.

Steve Parker, M.D.

About Dayspring and Underberg:

Thomas Dayspring MD, FACP, FNLA   Director of Cardiovascular Education, The Foundation for Health Improvement and Technology, Richmond, VA. Clinical Assistant Professor of Medicine, University of Medicine and Dentistry of New Jersey, New Jersey Medical School.

James Underberg MD, FACP, FNLA   Clinical Assistant Professor of Medicine in the Division of General Internal Medicine at NYU Medical School and the NYU Center for Cardiovascular Disease Prevention . Director of the Bellevue Hospital Primary Care Lipid Management Clinic.

h/t Dr. Axel Sigurdsson

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Filed under coronary heart disease, Heart Disease, Uncategorized

Low-Carb Research Update

“What about that recent study in American Journal of Clinical Nutrition…?”

As much as possible, I base my nutrition and medical recommendations on science-based research published in the medical literature.  Medical textbooks can be very helpful, but they aren’t as up-to-date as the medical journals.

In the early 2000s, a flurry of research reports demonstrated that very-low-carb eating (as in Dr. Atkins New Diet Revolution) was safe and effective for short-term weight management and control of diabetes.  I was still concerned back then about the long-term safety of the high fat content of Atkins.  But 80 hours of literature review in 2009 allowed me to embrace low-carbohydrate eating as a logical and viable option for many of my patients.  The evidence convinced me that the high fat content (saturated or otherwise) of many low-carb diets was little to worry about over the long run.

By the way, have you noticed some of the celebrities jumping on the low-carb weight-management bandwagon lately?  Sharon Osbourne, Drew Carey, and Alec Baldwin, to name a few.

My primary nutrition interests are low-carb eating, the Mediterranean diet, and the paleo diet.  I’m careful to stay up-to-date with the pertinent scientific research.  I’d like to share with you some of the pertinent research findings of the last few years.

Low-Carb Diets

  • Low-carb diets reduce weight, reduce blood pressure, lower triglyceride levels (a healthy move), and raise HDL cholesterol (another good trend).  These improvements should help reduce your risk of heart disease.  (In the journal Obesity Reviews, 2012.)
  • Dietary fat, including saturated fat, is not a cause of vascular disease such as heart attacks and atherosclerosis (hardening of the arteries).  (Multiple research reports.)
  • If you’re overweight and replace two sugary drinks a day with diet soda or water, you’ll lose about four pounds over the next six months.  (American Journal of Clinical Nutrition, 2012.)
  • United States residents obtain 40% of total calories from grains and added sugars.  Most developed countries are similar.  Dr. Stephan Guyenet notes that U.S. sugar consumption increased steadily “…from 6.3 pounds [2.9 kg] per person per year in 1822 to 107.7 pounds [50 kg] per person in 1999.  Wrap your brain around this: in 1822 we ate the amount of added sugar in one 12-ounce can of soda every five days, while today we eat that much sugar every seven hours.”
  • A very-low-carb diet improves the memory of those with age-related mild cognitive impairment. Mild cognitive impairment is a precursor to dementia.  (University of Cincinnati, 2012.)
  • High-carbohydrate and sugar-rich diets greatly raise the risk of mild cognitive impairment in the elderly. (Mayo Clinic study published in the Journal of Alzheimers’ Disease, 2012.)
  • Compared to obese low-fat dieters, low-carb dieters lose twice as much fat weight.  (University of Cincinnati, 2011.)
  • Diets low in sugar and refined starches are linked to lower risk of age-related macular degeneration in women.  Macular degeneration is a major cause of blindness.  (University of Wisconsin, 2011.)
  • A ketogenic (very-low-carb) Mediterranean diet cures metabolic syndrome (Journal of Medicinal Food, 2011.)
  • For type 2 diabetics, replacing a daily muffin (high-carb) with two ounces (60 g) of nuts (low-carb) improves blood sugar control and reduces LDL cholesterol (the “bad” cholesterol). (Diabetes Care, 2011.)
  • For those afflicted with fatty liver, a low-carb diet beats a low-fat diet for management. (American Journal of Clinical Nutrition, 2011.)
  • For weight loss, the American Diabetes Association has endorsed low-carb (under 130 g/day) and Mediterranean diets, for use up to two years. (Diabetes Care, 2011.)
  • High-carbohydrate eating doubles the risk of heart disease (coronary artery disease) in women.  (Archives of Internal Medicine, 2010.)
  • One criticism of low-carb diets is that they may be high in protein, which in turn may cause bone thinning (osteoporosis).  A 2010 study shows this is not a problem, at least in women.  Men were not studied.  (American Journal of Clinical Nutrition.)
  • High-carbohydrate eating increases the risk of developing type 2 diabetes (American Journal of Clinical Nutrition, 2010.)
  • Obesity in U.S. children tripled from 1980 to 2000, rising to 17% of all children.  A low-carb, high-protein diet is safe and effective for obese adolescents.  (American Journal of Clinical Nutrition, 2010.)

Mediterranean Diet

The traditional Mediterranean diet is well established as a healthy way of eating despite being relatively high in carbohydrate: 50 to 60% of total calories.  It’s known to prolong life span while reducing rates of heart disease, cancer, strokes, diabetes, and dementia.  The Mediterranean diet is rich in fresh fruits, vegetables, nuts and seeds, olive oil, whole grain bread, fish, and judicious amounts of wine, while incorporating relatively little meat.  It deserves your serious consideration.  I keep abreast of the latest scientific literature on this diet.

  • Olive oil is linked to longer life span and reduced heart disease.  (American Journal of Clinical Nutrition, 2012.)
  • Olive oil is associated with reduced stroke risk.  (Neurology, 2012).
  • The Mediterranean diet reduces risk of sudden cardiac death in women.  (Journal of the American Medical Association, 2011.)
  • The Mediterranean diet is linked to fewer strokes visible by MRI scanning.  (Annals of Neurology, 2011.)
  • It reduces the symptoms of asthma in children.  (Journal of the American Dietetic Association, 2011.)
  • Compared to low-fat eating, it reduces the incidence of type 2 diabetes by 50% in middle-aged and older folks.  (Diabetes Care, 2010.)
  •  A review of all available well-designed studies on the Mediterranean diet confirms that it reduces risk of death, decreases heart disease, and reduces rates of cancer, dementia, Parkinson’s disease, stroke, and mild cognitive impairment.  (American Journal of Clinical Nutrition, 2010.)
  • It reduces the risk of breast cancer.  (American Journal of Clinical Nutrition, 2010.)
  • The Mediterranean diet reduces Alzheimer’s disease.   (New York residents, Archives of Neurology, 2010).
  • It slows the rate of age-related mental decline.  (Chicago residents, American Journal of Clinical Nutrition, 2010.)
  • In patients already diagnosed with heart disease, the Mediterranean diet prevents future heart-related events and preserves heart function.  (American Journal of Clinical Nutrition, 2010.)

Clearly, low-carb and Mediterranean-style eating have much to recommend them.  Low-carb eating is particularly useful for weight loss and management, and control of diabetes, prediabetes, and metabolic syndrome.  Long-term health effects of low-carb eating are less well established.  That’s where the Mediterranean diet shines.  That’s why I ask many of my patients to combine both approaches: low-carb and Mediterranean.  Note that several components of the Mediterranean diet are inherently low-carb: olive oil, nuts and seeds, fish, some wines, and many fruits and vegetables.  These items easily fit into a low-carb lifestyle and may yield the long-term health benefits of the Mediterranean diet.  If you’re interested, I’ve posted on the Internet a Low-Carb Mediterranean Diet that will get you started.

Steve Parker, M.D.

Disclaimer:  All matters regarding your health require supervision by a personal physician or other appropriate health professional familiar with your current health status.  Always consult your personal physician before making any dietary or exercise changes.

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Filed under Carbohydrate, Fat in Diet, Health Benefits, Heart Disease, ketogenic diet, Mediterranean Diet, nuts, olive oil, Stroke, Vegetables, Weight Loss

Heart Disease Death Rates For Diabetics Falling Fast

MedPage Today on May 22, 2012, reported a dramatic drop in cardiovascular death rates for folks with diabetes:

The death rate from cardiovascular disease in U.S. adults with diabetes fell 40% from 1997 to 2004, CDC and NIH researchers said.

And that’s not all:

Additionally, all-cause mortality in diabetic participants dropped by 23% (95% CI 10% to 35%), Gregg and colleagues reported, from 20.3 to 15.1 per 1,000 person-years after adjusting for age.

The researchers identified several factors that likely account for the improved life expectancy for diabetic Americans.

Among them was the “steady improvements in quality and organization of care, self-management behaviors, and medical treatments, including pharmacological treatment of hyperlipidemia and hypertension,” Gregg and colleagues suggested.

The MedPage Today article didn’t define cardiovascular disease.  It typically includes heart attacks, heart failure, strokes, aortic aneurysms, among a few others.

Hope that cheers you up!

Steve Parker, M.D. 

PS: Here’s the original research article in the current issue of Diabetes Care.

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Filed under coronary heart disease, Diabetes Complications, Heart Disease, Stroke

Is It More Important To Be Fit, Or Healthy Weight?

Men live longer if they maintain or improve their fitness level over time, according to research out of the Cooper Clinic in Dallas, Texas.  Part of that improved longevity stems from reduced risk of death from cardiovascular disease (e.g., heart attack and stroke). 

Compared with men who lose fitness with aging, those who maintained their fitness had a 30% lower risk of death; those who improved their fitness had a 40% lower risk of death.  Fitness was judged by performance on a maximal treadmill exercise stress test.

Body mass index over time didn’t have any effect on all-cause mortality but was linked to higher risk of cardiovascular death.  The researchers, however, figured that losses in fitness were the more likely explanation for higher cardiovascular deaths.  In other words, as men age, it’s more important to maintain or improve fitness than to lose excess body fat or avoid overweight.

Steve Parker, M.D.

Reference: Lee, Duck-chul, et al.  Long-term effects of changes in cardiorespiratory fitness and bodly mass index on all-cause and cardiovascular disease mortality in menCirculation, 124 (2011): 2,483-2,490

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Filed under Exercise, Longevity, Overweight and Obesity

Heart Patients: Mediterranean Diet to the Rescue!

The Mediterranean diet preserves heart muscle performance and reduces future heart disease events, according to Greek researchers reporting in the American Journal of Clinical Nutrition, May 19, 2010.

Reuters and other news services have covered the story.

The Mediterranean diet is well-established as an eating pattern that reduces the risk of death or illness related to cardiovascular disease—mostly heart attacks and strokes. Most of the studies in support of the heart-healthy diet looked at development of disease in general populations. The study at hand examined whether the diet had any effect on patients with known heart disease, which has not been studied much.

How Was the Study Done?

The study population was 1,000 consecutive patients admitted with heart disease to a Greek hospital between 2006 and 2009. In this context, heart disease refers to a first or recurrent heart attack (70-80% of participants) or unstable angina pectoris. Acute heart attacks and unstable angina are “acute coronary syndromes.” Average age was 64. Sixty percent had a prior diagnosis of cardiovascular disease (coronary heart disease or stroke). Thirty percent had diabetes. At the time of hospitalization, half had diminished function of the main heart pumping chamber (the left ventricle), half had normal pump function. Men totalled 788; women 212.

On the third hospital day, participants were given a 75-item food frequency questionnaire asking about consumption over the prior year. If a potential enrollee died in the first two hospital days, he was not included in the study. A Mediterranean diet score was calculated to determine adherence to the Mediterranean diet. Mediterranean diet items were nonrefined cereals and products, fruits, nuts, vegetables, potatoes, dairy products, fish and seafood, poultry, red meats and meat products, olive oil, and alcohol.

Left ventricle function was determined by echocardiogram (ultrasound) at the time of study entry, at the time of hospital discharge, and three months after discharge. Systolic dysfunction was defined as an ejection fraction of under 40%. [Normal is 65%: when the left ventricle is full of blood, and then squeezes on that blood to pump it into the aorta, 65% of the blood squirts out.]

Participants were then divided into two groups: preserved (normal) systolic left ventricular function, or diminished left ventricular function.

They were followed over the next two years, with attention to cardiovascular disease events (not clearly defined in the article, but I assume including heart attacks, strokes, unstable angina, coronary revascularization, heart failure, arrhythmia, and death from heart disease or stroke.

Results

  • Four percent of participants died during the initial hospitalization.
  • At the three month follow-up visit, those with greater adherence to the Mediterranean diet (a high Mediterranean diet score) had higher left ventricular performance (P=0.02).
  • At the time of hospital admission, higher ejection fractions were associated with greater adherence to the Mediterranean diet (P<0.001).
  • Those who developed diminished left ventricular dysfunction had a lower Mediterranean diet score (P<0.001)
  • During the hospital stay, those in the highest third of Mediterranean diet score had lower in-hospital deaths (compared with the lower third scores) (P=0.009).
  • Among those who survived the initial hospitalization, there was no differences in fatal cardiovascular outcomes based on Mediterranean diet score.
  • Food-specific analysis tended to favor better cardiovascular health (at two-year follow-up) for those with higher “vegetable and salad” and nut consumption. No significant effect was found for other components of the Mediterranean diet score.
  • Of those in the highest third of Mediterranean adherence, 75% had avoided additional fatal and nonfatal cardiovasclar disease events as measured at two years. Of those in the lowest third of Mediterranean diet score, only 53% avoided additional cardiovascular disease events.

The Authors’ Conclusion

Greater adherence to the Mediterranean diet seems to preserve left ventricular systolic function and is associated with better long-term prognosis of patients who have had an acute coronary syndrome.

My Comments

I agree with the authors’ conclusion.

We’re assuming these patients didn’t change their way of eating after the initial hospitalization. We don’t know that. No information is given regarding dietary instruction of these patients while they were hospitalized. In the U.S., such instruction is usually given, and it varies quite a bit.

In this study, lower risk of cardiovascular death was linked to the Mediterranean diet only during the initial hospital stay. Most experts on the Mediterranean diet would have predicted lower cardiovascular death rates over the subsequent two years. Mysteriously, the authors don’t bother to discuss this finding.

For those who don’t enjoy red wine or other alcoholic beverages, this study suggests that the Mediterranean diet may be just as heart-healthy without alcohol. A 2009 study by Trichopoulou et al suggests otherwise.

Steve Parker, M.D.

Reference:  Chrysohoou, C., et al. The Mediterranean diet contributes to the preservation of left ventricular systolic function and to the long-term favorable prognosis of patients who have had an acute coronary event.  American Journal of Clinical Nutrition 2010.  DOI: 10.3945/ajcn.2009.28982

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Filed under Alcohol, coronary heart disease, Health Benefits, Mediterranean Diet

Vitamins Slow Rate of Brain Shrinkage in Elderly

A cocktail of three common vitamins slowed the rate of brain shrinkage over two years  in elderly patients with mild cognitive impairment, according to researchers at the University of Oxford.  Less brain shrinkage should translate to better brain functioning.  People with diabetes need to know about this since diabetes is associated  with age-related cognitive impairment and dementia.  The dementia connection is debatable.

As a hospitalist, I see 10 or 20 brain scans every week.  A healthy 40-year-old brain nicely fills out the allotted space in the skull.  Most 70-year-old brains have an obvious degree of shrinkage.  Those with the most shrinkage typically have worse mental functioning, often diagnosed clinically as dementia, or its precursor, mild cognitive impairment (MCI).

The medical term for brain shrinkage is brain atrophy.  It reflects loss of brain cells or decrease in brain cell size.  I see A LOT of atrophied brains and impaired mental functioning—aka diminished cognition—in the elderly. 

Not everybody with atrophy has mental impairment; healthy brains slowly atrophy with age.  Alzheimer’s disease patients atrophy quickly; MCI patients atrophy at an intermediate rate.  MCI patients converting over the years to Alzheimer’s show a faster rate of atrophy.

Mild cognitive impairment affects 14 to 18% of those over age 70 (five million in the U.S.).  Half of these convert to Alzheimer’s disease or another dementia within five years.  We desperately need a way to prevent or slow that conversion.

That’s why I was excited to see a research report in which brain atrophy was slowed with three simple daily vitamins: folic acid 800 mcg, B12 500 mcg, and B6 20 mg.  (One Centrum vitamin, by comparison, provides folic acid 400 mcg, B12 6 mcg, and B6 2 mg).  The investigators will report later on whether the vitamins helped prevent mental decline.

These three vitamins are involved in homocysteine metabolism; they decrease blood levels of homocysteine.  Read elsewhere if you want the boring details. 

Methodology

Oxford area participants were at least 70 years of age and had mild cognitive impairment but not dementia.  Blood homocysteine levels were drawn periodically.  Participants were randomized to take either placebo (83 subjects) or the daily vitamins (85 subjects) for two years.  MRI scans were done periodically to determine brain volume.  Tests of mental functioning were done periodically.  More subjects were in the study at the outset but some dropped out and others didn’t have technically adequate MRI scans.

Results

After adjustment for age, the annual rate of brain atrophy was 30% less in the vitamin group compared to placebo.

For the placebo group, the rate of brain atrophy was clearly related to baseline homocysteine levels: higher homocysteine, faster atrophy.

Although the study was not powered to detect an effect of treatment on cognition (findings to be reported separately), in a post hoc analysis, we noted that final cognitive test scores were correlated to the rate of atrophy.

Atrophy appears to be a major determinant of cognitive decline in this population.

There were no significant safety issues and no differences in adverse events between the groups.

The vitamin group lowered homocysteine levels by 32% compared to placebo.

Reduction in brain shrinkage rate was best in those with a higher baseline homocysteine level (over 13 micromol/L); those with the lowest baseline levels (<9.5 micromol/L) showed no effect of vitamin therapy.  [In the U.S., 13% of those over 60 have concentrations over 13 micromol/L, whereas the median is 10 micromol/L.]

Comments

Although this is small study, I’m excited about the future clinical implications.  The results need to be replicated.  I can’t wait to hear from this group regarding the details of mental functioning tests.  If preservation of brain function or other practical benefits don’t accompany a slower rate of atrophy , it’s no use taking the vitamins.

A 2008 study found no clinical benefit with a similar vitamin mix in Alzheimer’s patients with mild to moderate disease.  In other words, the rate of mental decline was no different than the placebo group.  Average homocysteine level was 9.16 micromole/L and fell by 30% during the 18-month-long study.  Even those with the highest homocysteine levels showed no benefit.  Perhaps B vitamins need to be started much earlier in the disease process to be effective.

The time may come where we screen all 60-year-olds for above-average homocysteine levels, starting them on the vitamin cocktail.

One caveat, however.  Ten years ago doctors were quite excited about preventing heart disease events (e.g., heart attacks, cardiac deaths) and strokes in people with high homocysteine levels.  We knew that high levels were associated with cardiac events and strokes, and we knew the B vitamins would lower the blood levels.  We learned a couple years ago that B vitamin therapy actually didn’t help heart patients or those at high risk for heart disease.  Nor do the vitamins prevent strokes.  [If you’re a heart patient still taking Foltx, ask your cardiologist if it’s OK to stop it now.]

Steve Parker, M.D.

References: 

Smith, David, et al.  Homocysteine-lowering by B vitamins slows the rate of accelerated brain atrophy in mild cognitive impairment: A randomized controlled trial.  PLoS ONE 5(9): e1244.  doi: 10.1371/journal.pone.0012244  [published September 8, 2010]

Aisen, P.S., et al.  High-dose B vitamin supplementation and cognitive decline in Alzheimer disease: A randomized controlled trial.  Journal of the American Medical Association, 300 (2008): 1,774-1,783.

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Filed under Diabetes Complications