Posts Tagged ‘mortality’

Study Affirms that Central Obesity has Higher Mortality Risk

November 21st, 2015

A new article reaffirms earlier studies showing that in persons with a normal Body Mass Index (BMI) had the worst long-term survival compared to others with a similar BMI but no central obesity and twice the mortality risk of persons who were overweight or obese according to BMI.


More evidence on obesity and mortality. Where did the obesity paradox go?

January 15th, 2014

The January 16, 2013 issue of the New England Journal of Medicine contains an article by Frank Hu and colleagues looking at mortality among adults with incident type 2 diabetes by Body Mass Index (BMI). Using two large databases, they found a J-shaped association between BMI and mortality among those who had ever smoked and a direct, linear relationship among those who had never smoked. They found no evidence of an “obesity paradox,” the supposed protective effective of overweight. They concluded, “…given the relationship of overweight and obesity to other critical public health end points (e.g. cardiovascular disease and cancer), the maintenance of a healthy body weight should remain the cornerstone of diabetes management, irrespective of smoking cessation.” The article is a contribution to the understanding of obesity’s relationship with premature mortality but will surely not be the last word on this topic.


Obesity Mortality Estimate Sharply Up

August 22nd, 2013

In a new analysis, researchers have determined that mortality due to obesity is much greater than previously estimated, perhaps some 4 times as higher as previous estimates. The new analysis is based on looking at age, race and gender cohorts between 1986 and 2006.


D is For Disease, Death and Disability

July 8th, 2013

Supposed you woke up and the TV news and newspapers revealed that scientists had discovered a global threat affecting all races, both genders, reducing lifespans and causing millions of cases of disabilities, likely to cost billions of dollars a year. There was no clear cause and no treatment which seemed available, except, in some cases, surgically removing part of the GI track seemed to work…for a while.

What would you say? “Who cares”? “It’s their own fault”? “How much is this going to cost me?”  Perhaps, you would call your Congressional representative and Senator and demand a crash research program to find a cure? Or you could quibble for, say, forty years or so, over who is to blame and whether this “threat” is a condition, syndrome, risk factor or (God forbid!) a disease? Well, the latter is pretty much what we have been doing about obesity. Three new papers show the impact of obesity on mortality, disability and disability-related health care costs, reminding us of the toll this disease takes on the human body.

First, regarding mortality, a great number of studies have been published and the public is still confused. Now, Chang and colleagues, have published a paper in which they are able to predict life years lost associated with obesity-related diseases for non-smoking US adults. They found that obesity-related comorbidities are associated with large decreases in life years and increases in mortality rates. Years of life lost is more marked for younger than older adults, for blacks more than whites, for males than females and for more obese than less obese. Their study confirmed that being obese or underweight increased the risk of mortality. Furthermore, an obesity-related disease, such as coronary heart disease, hypertension, diabetes and stroke, increased the chances of dying and decreased life years by 0.2 to 11.7 years, depending on gender, race, BMI and age.  Obesity-related diseases were expected to shorten lifespan of people in their 20s by more than 5 years, while people in their 60s were predicted to lose just under one year of life. See, Chang SH, Pollack LM, Colditz, Life Years Lost Associated with Obesity-Related Diseases for U.S. Non-Smoking Adults.

Obesity-related diseases are also only partially understood. Type 2 diabetes and heart disease are commonly associated with obesity but there are a host of other conditions which are less well-known and appreciated. Among these are the disabling conditions associated with obesity. Brian S. Armour, et al, have looked at disability prevalence among persons who are obese. Of the 25.4% of US adults who are obese (53.4 million), 41.7% reported a disability in contrast to 26.7% of those at a healthy weight and 28.5% of those who were overweight. Movement difficulty was the most common type of basic action difficulty, affecting 32.5% of the adults with obesity. Of course, movement difficulties can hinder physical activity for weight loss.

Work limitations affected 16.6% of the adults with obesity. Visual difficulty was the common sensory difficulty at 11.5%, probably attributable to type 2 diabetes.  20.5% of adults with obesity reported complex activity limitation, compared to 12% of those at a healthy weight. All estimates for disability were significantly higher for people who were obese compared to those with a healthy weight. The prevalence of cognitive difficulty, contrary to Hank Cardello’s implications, was low at 3.6% for persons with obesity. However, persons at a healthy weight had higher cognitive difficulty than those who are overweight, 2.9% v. 2.4%. Armour BS, Courtney—Long EA, Campbell VA, Wethington HR, Disability Prevalence among health weight, overweight, and obese adults. Obesity, 2013 Apr.21 (4); 852-5.

Wayne L. Anderson, Joshua M. Weiner and colleagues widen the picture of persons who are obese with disabilities in terms of health care costs. Their new study estimates the additional average health care expenditures for overweight and obese adults with and without disabilities. They found that people with disabilities who were obese had almost three times the additional average costs of obesity compared to people without disabilities, $2,459 v. $889. Prescription drug costs were 3 times higher and outpatient expenditures were 74% higher. People with disabilities in the 45-64 year age group had the highest obesity expenditures. Overweight people with and without disabilities had lower expenditures than normal-weight people with and without disabilities. The authors note, “A substantial portion of people with disabilities are obese. People with disabilities are at higher risk of obesity because some conditions such as arthritis and diabetes are characterized by high levels of functional impairment. Arthritis can readily limit mobility, which may result in substantial weight gain over time. For diabetes, weight gain can be a byproduct of insulin use if patients do not effectively manage their weight. The coexistence of disability, obesity, and serious chronic conditions may result in very high health care expenditures.” Anderson WL, Wiener JM, Khatutsky G, Armour, BS Obesity and People with Disabilities: The Implications for Health Care Expenditures. Obesity, 2013 June 26, (epub ahead of print).

So, obesity is a driver of mortality and morbidity but is not a disease? Eh?


Obesity’s Effect in Motor Vehicle Crashes

December 22nd, 2011

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

Understanding Obesity and Mortality

November 20th, 2011

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

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

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