Health for life

Its such a no-brainer, right?  If persons at risk for diabetes would only eat right and exercise more, theyd avoid the disease.  And for those who develop diabetes, diet and exercise will reduce death rates and complications.

Yes and no, say Elizabeth Sumamo Schellenberg and colleagues at the University of Alberta.  Their review of the mixed published scientific evidence on the topic appears in the October 15 issue of the Annals of Internal Medicine.  The purpose of their study was to ascertain the impact of diet and exercise on the prevention of "Type 2 diabetes," as well as lowering complications among persons with who had established Type 2 diabetes. 

To be included, studies had to be prospective and compare the outcomes from an intervention versus a randomly selected control group. The study could only be included if it examined the impact of exercise plus diet and "one other component," such as "counseling, smoking cessation and behavior modification."  The outcomes had to include the development of Type 2 diabetes (in the prevention trials) or complications (in the treatment trials).

1289 candidate studies were found but only 20 made the grade. Nine were prevention trials and 11 were treatment trials.

For the prevention trials:

The interventions lasted from 6 to 72 months, with follow-up going for 3 to 20 years for between 39 to 3234 participants.  The counseling varied and included group and/or individual with or without tobacco cessation, telephony, goal setting, cooking classes or pills involving a range of physician and non-physician professionals.

Results?

Seven of the nine studies showed that diabetes can be delayed. When the results were pooled, compared to the control patients, the risk of developing diabetes over 10 years was only a third and the difference was statistically significant.

But, there was no detectable impact on cardiovascular disease events or on eye, kidney or nerve damage. That may have been due to not all the studies including these outcomes as well as the time it takes for these complications to occur once diabetes develops.  With more patients or more time, a difference could have become apparent.
 
For the treatment trials:

The interventions lasted from 6 to 48 months with follow-up for 6 to 93 months. The counseling was as varied as the prevention trials but included glucose and blood pressure monitoring as well as stress management and, in one instance, a three day residential retreat. There was likewise the range of professionals who provided the interventions.

Results? 

Compared to the control patients, there was no statistically significant difference in all-cause mortality.  Some individual studies had beneficial outcomes involving cardiovascular events or diabetes complications, but they included the aggressive use of medications.  There were no sustained impacts on weight or dietary intake.  And if pills were not included, there was also no real improvement in measures of blood glucose control.

The Disease Management Care Blogs take?

The good news is that there is good evidence that exercise and diet can prevent diabetes.  The bad news is that it takes years for that "return on investment" to declare itself and typically involves interventions that fall outside the traditional health care delivery system.  Its unlikely, thinks the DMCB, that current iterations of payment orm (value based purchasing, bundled payments or upside risk) can be marshaled to make this a reality.  That being said, population health management (PHM) companies like Omada Health are making their evidence-based services available to, for example, employers who have a longer term commitment to the well being of their "human capital" outside of the traditional insurance market.

The bad news is that once diabetes declares itself, diet and exercise dont result in life extension, and control of complications as well as overall blood sugar levels is more a function of pills than lifestyle. Accordingly, expectations need to be realisitically shared with patients and PHM should emphasize taking the pills as prescribed.

Image from Wikipedia

Change in Weight More Important Than Where You Start

Some overweight older adults don’t need to lose weight to extend their lives, but they could risk an earlier death if they pack on more pounds.

In fact, the nationwide study found that people who were slightly overweight in their 50s but kept their weight relatively stable were the most likely to survive over the next 16 years.

They had better survival rates than even normal-weight individuals whose weight increased slightly, but stayed within the normal range.

On the other hand, those who started out as very obese in their 50s and whose weight continued to increase were the most likely to die during that period.

Overall, the results suggest that about 7.2 percent of deaths after the age of 51 are due to weight gain among obese people, at least among the generation in this study, said Hui Zheng, lead author of the study and assistant professor of sociology at The Ohio State University.

“You can learn more about older people’s mortality risk by looking at how their weight is changing than you can by just looking at how much they weigh at any one time,” Zheng said.

While some extra weight seemed protective in this study, Zheng cautioned that these results applied only to people over 50. His previous research, published in Social Science & Medicine, suggests that being overweight may not be helpful for younger people.

“Our other research suggests that the negative effect of obesity on health is greater for young people than it is for older people, so young people especially shouldn’t think that being overweight is harmless,” he said.

This new study was published online this month in the American Journal of Epidemiology. Co-authors are Dmitry Tumin, doctoral student, and Zhenchao Qian, professor, both in sociology at Ohio State.

The researchers used data from the Health and Retirement Study, a nationally representative survey of Americans born between 1931 and 1941. This study analyzed 9,538 respondents who were aged 51 to 61 when the survey began in 1992. They were re-interviewed every two years until 2008, and the researchers had information on how their body mass index (BMI) changed at each interview and whether they died at any point before December 2009.

Body mass index measures weight relative to height and is often used to evaluate obesity.

Zheng and his colleagues classified respondents into six groups, depending on their BMI at the beginning of the study and how it changed over the 16-year period they were surveyed.

While slightly overweight people (BMI of 25 to 29.9) whose weight was steady had the highest survival rate, those who moved from overweight to obese (BMI 30 to 34.9) were close behind.

“This suggests that among overweight people at age 51, small weight gains do not significantly lower the probability of survival,” Zheng said.

The third highest survival rate among the six groups was normal weight individuals (BMI of 18.5 to 24.9) whose weight increased slightly, but stayed within normal range.

Next came the Class I obese (BMI of 30 to 34.9) whose weight was moving upward.

“You can learn more about older people’s mortality risk by looking at how their weight is changing than you can by just looking at how much they weigh at any one time.”

Next to last were normal weight individuals who lost weight. Although the study attempted to control for illnesses among those studied, it may be that many of these individuals dropped weight because of illness.

The most obese individuals (BMI of 35 and over) who continued to add weight had the lowest survival rate of the six groups.

There weren’t enough people who started out as overweight and obese and lost weight to include in this analysis, Zheng said.

“We can’t really evaluate the effectiveness of planned weight loss on mortality. Even in the normal-weight people in this study, there was no way to tell whether weight loss was planned,” he said.

Zheng noted that the study took into account a wide variety of demographic and socioeconomic factors that may play a role in both weight and mortality among Americans. The researchers also controlled for whether the respondents smoked, whether they had a variety of chronic illnesses and even how they rated their own health. The results stood even after all of these factors were taken into account.

Why is being slightly overweight protective for older people?

“It is probably because the older population is more likely to get illnesses and disease, especially cancer, that cause dangerous weight loss,” he said. “In that case, a small amount of extra weight may provide protection against nutritional and energy deficiencies, metabolic stresses, the development of wasting and frailty, and loss of muscle and bone density caused by chronic diseases.”

Younger people are less likely to get many of the diseases that afflict older adults, which is one reason extra weight is not good for them, he said.

But Zheng said the main message for everyone, including older adults, is that packing on the pounds, especially if you’re obese, can be hazardous to your health.

“Continuing to put on weight can lower your life expectancy,” he said.

The issue of cholesterol is complex, to say the least.  You might not realize it from watching cholesterol-lowering drug commercials, or even from talking to your doctor.  But there is way more to the story than simply keeping your cholesterol low.  This will probably be a frequent topic on my blog, as there are so many aspects of it to be explored, but for today Id like to focus on total cholesterol.

Check out this very eye-opening paper.  Its an outstanding review of some of the more intriguing cholesterol research, and one of the few papers that Ive actually found difficult to put down.  I seriously couldnt stop reading it.  And it blew my mind.

According to several studies, older adults with higher cholesterol live the longest. In fact, groups with the lowest cholesterol levels typically have the highest morbidity rate.  Heres the breakdown from a couple of these studies...  Dr. Harlan Krumholz found in 1994 that old people with low cholesterol were twice as likely to die from coronary heart disease than those with high cholesterol.  Another study of 92 women aged 60 or over found that those with a total cholesterol level of about 270 mg/dl lived the longest.  Those with the highest cholesterol, over 300 mg/dl, were only 1.8 times more likely to die, while the lowest cholesterol group, 154 mg/dl, was 5.4 times more likely to die.

Interesting stuff huh?  That review paper discusses 20 studies just like these, where blood cholesterol levels were either not associated with cardiovascular disease or all-cause death, or there was an inverse relationship.  This quote from the paper sums up the situation quite nicely...

"It is true that high t-C is a risk factor for coronary heart disease, but mainly in young and middle-aged men. If high t-C or LDL-C were the most important cause of cardiovascular disease, it should be a risk factor in both sexes, in all populations, and in all age groups. But in many populations, including women, Canadian and Russian men, Maoris, patients with diabetes, and patients with the nephrotic syndrome; the association between t-C and mortality is absent or inverse; or increasing t-C is associated with low coronary and total mortality. Most strikingly, in most cohort studies of old people, high LDL-C or t-C does not predict coronary heart disease or all-cause mortality; in several of these studies the association between t-C and mortality was inverse, or high t-C was associated with longevity. These associations have mostly been considered as a minor aberration from the LDL-receptor hypothesis, although by far the highest mortality and the greatest part of all cardiovascular disease are seen in old people."

 In case youre having trouble with the terminology, t-C just means total cholesterol, LDL-C means LDL cholesterol.  A couple of key points here...  if cholesterol is the cause of heart disease, then shouldnt it be a risk factor for everybody, regardless of age, sex, or ethnicity?  It should.  But its not.  While cholesterol levels can be somewhat predictive of ones risk of heart disease, cholesterol doesnt cause the problem.  The second bolded quote is very key as well.  Studies done in older adults, like these ones showing that those with high cholesterol have less risk of cardiovascular disease, should not be taken as an aberration.  By far the highest risk group is adults over 60, so if the conventional wisdom doesnt hold true for them, it doesnt hold true at all.  These studies should indicate that our current thinking about cholesterol is highly flawed.  Cholesterol simply cannot be the cause of heart disease when it is so notoriously unreliable as a predictor of heart disease in the most at-risk populations.  Its that simple.