Obesity in Older People With and Without Conditions Associated With Weight Loss: Follow-up of 955,000 Primary Care Patients

Abstract

Background:Moderate obesity in later life may improve survival, prompting calls to revise obesity control policies. However, this obesity paradox may be due to confounding from smoking, diseases causing weight-loss, plus varying follow-up periods. We aimed to estimate body mass index (BMI) associations with mortality, incident type 2 diabetes, and coronary heart disease in older people with and without the above confounders.Methods:Cohort analysis in Clinical Practice Research Datalink primary care, hospital and death certificate electronic medical records in England for ages 60 to more than 85 years. Models were adjusted for age, gender, alcohol use, smoking, calendar year, and socioeconomic status.Results:Overall, BMI 30–34.9 (obesity class 1) was associated with lower overall death rates in all age groups. However, after excluding the specific confounders and follow-up less than 4 years, BMI mortality risk curves at age 65–69 were U-shaped, with raised risks at lower BMIs, a nadir between 23 and 26.9 and steeply rising risks above. In older age groups, mortality nadirs were at modestly higher BMIs (all <30) and risk slopes at higher BMIs were less marked, becoming nonsignificant at age 85 and older. Incidence of diabetes was raised for obesity-1 at all ages and for coronary heart disease to age 84.Conclusions:Obesity is associated with shorter survival plus higher incidence of coronary heart disease and type 2 diabetes in older populations after accounting for the studied confounders, at least to age 84. These results cast doubt on calls to revise obesity control policies based on the claimed risk paradox at older ages.

Long-term rates of change in musculoskeletal aging and body composition: findings from the Health, Aging and Body Composition Study

“…In general, increased fat mass in older age is related to increased risk of physical disability [12] and all-cause mortality [13], although some protective effects of being moderately overweight (25 ≤ body mass index [BMI] < 30) have been reported in relation to mortality in meta-analyses [14,15]. However, large studies accounting for smoking and diseases causing weight loss have identified obesity (BMI ≥ 30) and central-adiposity, indicated by greater waist-to-hip ratio, as risk factors for mortality, coronary heart disease and type 2 diabetes [16,17]. Age-related reductions in lean mass in combination with increases in fat mass can result in the development of sarcopenic obesity, resulting in more adverse health effects than sarcopenia or obesity in isolation [18].…”

Central adiposity and the overweight risk paradox in aging: follow-up of 130,473 UK Biobank participants

“…We found that in “healthier agers” (nonsmokers without disease-associated weight loss), class I obesity was associated with excess mortality and coronary artery disease (CAD) (13); that is, the obesity risk paradox reversed to being nonparadoxical. A further possible bias in the paradoxical associations for BMI-defined overweight (and class I obese) persons may be that BMI does not distinguish between fat and fat-free mass (6, 14).…”

Effect of body mass index on clinical outcome and all-cause mortality in patients undergoing transcatheter aortic valve implantation

“…According to the Framingham Heart study, conducted among participants (age: 30–49 years) with no cardiovascular disease at baseline, overweight and obesity were associated with a decrease in life expectancy and increased early mortality during the follow-up period of ≥4 years [ 5 ]. Accordingly, another population-based cohort reported an increased risk of all-cause mortality among elderly (≥85 years) obese participants [ 6 ]. In addition to the risk of mortality, obesity is an underlying promotor of systemic metabolic dysfunction, i. e., dyslipidaemia, decreased insulin sensitivity, hyperinsulinaemia, hyperglycaemia, and hypertension [ 2 , 4 ].…”