Increasing Rates of Some Cancers Associated with Obesity

January 28th, 2012 No comments »

Increasing rates of some cancers may be associated with obesity. Cancers with increasing incidence trends in… [CA Cancer J Clin. 2012] – PubMed – NCBI

Powerful New Study Underscores Obesity-Pain Relationship

January 28th, 2012 No comments »

A new survey of one million Americans found a high association between obesity and pain. Obesity and Pain Are Associated in t… [Obesity (Silver Spring). 2012] – PubMed – NCBIThey found the association was “robust” among both men and women. This survey involved an unusually high number of subjects and confirmed earlier studies.

Obesity holds back improvements in US health

December 27th, 2011 No comments »

Improvements in nation’s health stalls; obesity blamed in part. The United Health Foundation has released its 22nd annual report on the Nation’s health, finding no improvement, attributed at least in part, because of the rise in obesity. The report indicates that, for every person who quits smoking, another becomes obese. America’s Health Rankings and United Health Foundation

Obesity’s Effect in Motor Vehicle Crashes

December 22nd, 2011 No comments »

A recently published literature review has found that obesity is associated with high mortality and more lower extremity injuries in motor vehicle crashes but is, unexpectedly, protective for head injuries. Does Obesity Increase the Risk of I… [Asia Pac J Public Health. 2011] – PubMed – NCBI

American Heart Assn. Sees Tidal Wave of Cardiovascular Disease coming from Obesity Epidemic

December 16th, 2011 No comments »

The American Heart Association has published an update on the burden of cardiovascular disease and stroke. They warn that the recent drop in death rates is likely to be reversed by the continuing increases in the rates of diabetes and obesity. Dr. Donald Lloyd-Jones told MedPageToday  that rising death rates in cardiovascular death in young adults is particularly troubling, “Because if they’re getting disease at this young of an age then they’re just the leading edge – the canaries in the coal mine, if you will – that suggests that we have a whole tidal wave of cardiovascular disease that is coming as a result of the obesity epidemic.” Medical News: Diabetes, Obesity Overshadow Lower CV Death Rate – in Cardiovascular, Prevention from MedPage Today 

Here are the facts:

The estimated prevalence of overweight and obesity in US adults (>20 years of age) is 149 300 000, which represents 67.3% of this group in 2008. Fully 33.7% of US adults are obese (body mass index >30 kg/m2). Men and women of all race/ethnic groups in the population are affected by the epidemic of overweight and obesity.

● Among children 2 to 19 years of age, 31.9% are overweight and obese (which represents 23 500 000 children), and 16.3% are obese (12 000 000 children). Mexican American boys and girls and African American girls are disproportionately affected. Over the past 3 decades, the prevalence of obesity in children 6 to 11 years of age has increased from <4% to more than 20%.

● Obesity (body mass index >30 kg/m2) is associated with marked excess mortality in the US population. Even more notable is the excess morbidity associated with overweight and obesity in terms of risk factor development and incidence of diabetes mellitus, CVD end points (including coronary heart disease, stroke, and heart failure), and numerous other health conditions, including asthma, cancer, degenerative joint disease, and many others.

● The prevalence of diabetes mellitus is increasing dramatically over time, in parallel with the increases in prevalence of overweight and obesity.

● On the basis of NHANES 2003–2006 data, the age adjusted prevalence of metabolic syndrome, a cluster of major cardiovascular risk factors related to overweight/obesity and insulin resistance, is 34% (35.1% among men and 32.6% among women).

● The proportion of youth (<18 years of age) who report engaging in no regular physical activity is high, and the proportion increases with age. In 2007, among adolescents in grades 9 through 12, 29.9% of girls and 17.0% of boys reported that they had not engaged in 60 minutes of moderate-to-vigorous physical activity, defined as any activity that increased heart rate or breathing rate, even once in the previous 7 days, despite recommendations that children engage in such activity >5 days per week.

● Thirty-six percent of adults reported engaging in no vigorous activity (activity that causes heavy sweating and a large increase in breathing or heart rate).

● Data from NHANES indicate that between 1971 and 2004, average total energy consumption among US adults increased by 22% in women (from 1542 to 1886 kcal/d) and by 10% in men (from 2450 to 2693 kcal/d;

● The increases in calories consumed during this time period are attributable primarily to greater average carbohydrate intake, in particular, of starches, refined grains, and sugars. Other specific changes related to increased caloric intake in the United States include larger portion sizes, greater food quantity and calories per meal, and increased consumption of sugar-sweetened beverages, snacks, commercially prepared (especially fast food) meals, and higher energy-density foods.

For the full report, see Heart Disease and Stroke Statistics—2011 Update1. About 1. About These Statistics2. American Heart Association’s 2020 Impact Goals3. Cardiovascular Diseases4. Subclinical Atherosclerosis5. Coronary Heart Disease, Acute Coronary Syndrome, and Angina Pectoris6.

Understanding Obesity and Mortality

November 20th, 2011 No comments »

As we have discussed elsewhere, the association of obesity to increased mortality is complex. Studies vary. The “obesity-paradox” reflects studies showing that higher BMI was associated with lower mortality in hospitalized patients after a heart attack. Body Weight After Stroke: Lessons From the Obesity Pa… [Stroke. 2011] – PubMed – NCBI

Obesity-deniers exploit these studies to argue obesity is no big deal.

Now comes research out of Israel of older persons, age 75-94.  They found that obesity was significantly predictive of higher mortality for persons aged 75-84 but from 85 onward, obesity had a modest, non-statistically significant protective effect.

The authors suggest that the obesity-paradox may be disentangled in that there is a shift from detrimental to favorable influence of obesity from ages 80 to 90.  They speculate that persons with obesity lower rates of osteoporosis and extra energy reserves available in times of illness, stress and trauma may contribute to higher survival.  They write, “Decreased mortality among persons with obesity in very old ages may reflect a selective survival effect whereby persons who are more prone to the adverse health outcomes of obesity due to the effect of genetic or environmental factors suffer from higher mortality in middle age, which leaves a more resilient overweight older population. Another possible explanation is that of a ceiling effect, as absolute mortality long-term risk increases with age and eventually converges, regardless of any health-associated risk levels. Body Weight After Stroke: Lessons From the Obesity Pa… [Stroke. 2011] – PubMed – NCBI

Why is this important? First, it is a contribution in resolving the obesity-paradox and subsequent public confusion about obesity’s impact on survival. Second, it may impact current and future clinical trials. The Food and Drug Administration (FDA) sees obesity primarily (if not exclusively) as a cardiovascular risk factor. To determine if an anti-obesity drug reduces or increases cardiovascular risks, it is asking that clinical trials address this problem. However, for a clinical trial to study cardiovascular risks, it has to look to an older population than the typical weight-loss seeking patient, such as in the SCOUT trial. It has to go to an older population because cardiovascular disease is primarily a disease of an older population.Prevalence of Coronary Heart Disease — United States, 2006–2010

So, what if, as in this study, obesity is protective for some of the older population but not for others? How does this affect the outcome of the trials? Recall that in the SCOUT trial, there were relatively few cardiovascular events and the absolute number between those with events on and off the drug was quite small. So, this age difference could be quite significant.

Finally, consider this. In a study such as this, participants in their 80s were born in the 1920-30s. Odds are pretty good that they became obese during their adult years. Now, we have to consider that the population is becoming  obese at far younger ages and we do not know what effect the extra decades of higher weight will have on their mortality.

Cancer and Obesity Explored

November 3rd, 2011 No comments »

The Institute of Medicine’s National Cancer Policy Forum this week convened a two-day workshop, “The Role of Obesity in Cancer Survival and Recurrance.” So this is a good opportunity to re-visit the relationship between these two deadly diseases. Susan Gapstur of the American Cancer Society noted the growing list of cancers associated with obesity. For men, these include cancers of the colon, esophagus, kidney, colorectum, pancreas, gallbladder and liver. Women are affected by the same cancers as well as of the endometrium and postmenopausal breast cancer. Evidence is accumulating for an association with non-Hodgkin’s lymphoma, ovarian cancer in women and aggressive prostate in men. Obesity, she pointed out, is not the second (to tobacco) leading risk factor of cancer. Ominously, she pointed out we do not know what the health effects will be for the children now obesity who will obese for a lifetime.

Pamela J. Goodwin of the University of Toronto explored potential mechanisms in the progression to cancer including inflammation, adipokines, hyperinsulinemia, diabetes/diabetes drugs and sex steroids. She pointed to studies showing reductions in cancer risk with intentional weight loss of 20 pounds or more. Intentional weight loss and in… [Int J Obes Relat Metab Disord. 2003] – PubMed – NCBI and reduction in the relative risks of death and of cancer following bariatric surgery. Metabolic surgery and cancer: protective effects of b… [Cancer. 2011] – PubMed – NCBI.  Specifically, she showed the positive effect of intentional weight loss on breast cancer risk   Does intentional weight loss reduce canc… [Diabetes Obes Metab. 2011] – PubMed – NCBI and the impact of physical activity on improvements in insulin in breast cancer survivors Impact of a mixed strength and endurance exerci… [J Clin Oncol. 2008] – PubMed – NCBI.

Bruce Wolfe of the Oregon and Science University and a bariatric surgeon reminded the participants that the Swedish Obesity Study found the reduction in mortality after bariatric surgery was greater for cancer than for cardiovascular events Effects of bariatric surgery on mortality in Sw… [N Engl J Med. 2007] – PubMed – NCBI. In a Utah study, bariatric surgery reduced deaths from cancer by 60% compared to a 48% reduction in cardiovascular events. Long-term mortality after gastric bypass surgery. [N Engl J Med. 2007] – PubMed – NCBI

Rachel Ballard-Barbash of the National Cancer Institute, who has been a leader in exploring the obesity-cancer connection for many years, moved the discussion to look at the co-morbid conditions of obesity and their relationship to cancer mortality, including renal disease, congestive heart failure, cerebrovascular disease, citing A refined comorbidity measurement algorithm fo… [Ann Epidemiol. 2007] – PubMed – NCBI

Patricia Ganz of the UCLA Schools of Medicine picked up the point and explained that about half of all deaths of breast cancer survivors are due to causes other than breast cancer. She recommended prevention of weight gain and/or weight loss in those breast cancer survivors who are obese. 

Thomas Wadden described the non-surgical approaches to weight loss used in the Diabetes Prevention Program and the LOOK Ahead study and the contribution of intensive behavioral counseling to reduction in comorbid conditions associated with obesity

Some of the workshop’s presentations are on-line at Workshop on the Role of Obesity in Cancer Survival and Recurrence – Institute of Medicine. Watch that site for future information on a publication from the workshop.

New Mortality Data

September 26th, 2011 No comments »

Obesity’s contribution to increased mortality remains a controversial topic. In a new study, researchers from the University of Pennsylvania estimate that obesity reduced US life expectancy at age 50 by 1.54 years for women and by 1.85 years for men. They conclude that the high prevalence of obesity in the United States contributes substantially to the poor showing of the US in international rankings of longevity. Contribution of Obesity to International … [Am J Public Health. 2011] – PubMed – NCBI