Discussion
obesity, deaths, death, cancer, noncancer, CVD, weight gain, Weight gain, weight loss, Appetite
OBESITY, CVD, CANCER, CHRONIC ILLNESS, EVENTS, DISEASES
The principal finding of this study was that a weight loss of more than 10% was associated with higher all-cause mortality (including increased mortality from cancer, CVD, and noncancer non-CVD) among both men and women. The association was more pronounced among men, for whom, in absolute terms, subsequent all-cause mortality was 8.4% among those maintaining consistent weight over a mean (SD) of 4.4 (1.7) years vs 30.1% among those for whom weight decreased by more than 10%; for women, the equivalent mortality rates were 5.5% and 12.6%. Lesser weight loss (between 5% and 10%) was associated with higher all-cause mortality for both sexes compared with stable weight, as well as a higher cancer mortality for women and a higher noncancer non-CVD mortality for men.A decrease in WC was also associated with increased mortality. Weight gain, however, was not significantly associated with mortality, with the possible exception of noncancer non-CVD mortality for women. However, based on the small number of events in that category, this result should be interpreted cautiously.Previous studies have reported an association between weight loss and subsequent mortality, but these studies included only a small number of older adults, typically with multiple comorbidities (eTable 14 in Two previous longitudinal studies examined the association of weight loss with CVD and cancer mortality and yielded conflicting results. The Enquête de Santé Psychologique-Risques, Incidence et Traitement (ESPRIT) study showed that weight loss was associated with higher CVD mortality but not cancer mortality.Our study demonstrates that weight loss in older men and women is associated with an increased mortality risk irrespective of an individual’s baseline weight (ie, unanticipated weight loss even among adults with obesity is associated with increased mortality, regardless of other potential benefits of weight loss that are associated with quality of life and other morbidities). In addition, our study has clarified the lesser implications of weight gain. Compared with previous reports, the present study is based on individual measures of weight (rather than self-report) and adjudicated assessments of the cause of death. Without adjudication, deaths among older populations may be misclassified in up to 30% cases.The observation that weight loss was associated with mortality among men may be the result of the different body composition characteristics of men and women.A likely explanation for these findings is that weight loss can be an early prodromal indicator of the presence of various life-shortening diseases.In this age group, weight loss was largely associated with a reduction of appetite, leading to reduced food intake. Appetite is a complex process, governed by both the central nervous system and various circulating hormones. Several proposals have been put forward to explain why appetite might be suppressed in the early stages of chronic illness, ranging from increases in resistance to appetite-stimulating hormones,