INVOLUNTARY WEIGHT-LOSS IN OLDER OUTPATIENTS - INCIDENCE AND CLINICAL-SIGNIFICANCE

OBJECTIVES: To describe the incidence, anthropometric parameters, and clinical significance of weight loss in older outpatients. DESIGN: Fou r-year prospective cohort study. SETTING: University-affiliated Vetera ns Affairs Medical Center. PATIENTS: Two hundred forty-seven community -dwelling male veterans 65 years of age or older. MEASUREMENTS: Anthro pometrics (weight, height, skinfolds, and circumferences), health stat us measures (Sickness Impact Profile scores, health care utilization, self-reported ratings of health), and bloodwork (cholesterol, albumin, others) were obtained at baseline and followed annually for 2 years. Outcome measures (hospitalization, nursing home placement, and mortali ty rates) were followed for a minimum of 2 years after any identified weight change. MAIN RESULTS: The mean annual percentage weight change for the study population was -0.5% (SD: +/-4.0%; range: -17% to +25%). Four percent annual weight loss was determined to be the optimal cutp oint for defining clinically important involuntary weight loss using R OC curve analysis. The annual incidence of this degree of involuntary weight loss was 13.1%. At baseline, involuntary weight losers were sim ilar to nonweight losers in age (73.9 +/- 7.9 vs 73.3 +/- 6.7 years), body mass index (26.8 +/- 3.9 vs 26.9 +/- 4.1 kg/m(2)),and all other a nthropometric, health status, and laboratory measures. Relative to non weight losers, involuntary weight losers had significantly (P less tha n or equal to .05) greater decrements in central skinfold and circumfe rence measures (subscapular skinfolds, -2.9 vs -0.4 mm; suprailiac ski nfolds, -4.2 vs -0.2 mm; and waist to hip ratio, -.01 vs +.00). Both g roups had significant decreases in their triceps skinfolds (an estimat e of peripheral subcutaneous fat), whereas arm muscle area and albumin levels did not decline significantly in either group. Over a 2-year f ollow-up period, mortality rates were substantially higher (RR = 2.43; 95% CI = 1.34-4.41) among involuntary weight losers (28%) than among nonweight losers (11%). Of interest, a similar increase in 2-year mort ality (36%) was also observed among subjects with voluntary weight los s (by dieting). Survival analyses adjusting for differences between we ight losers and nonweight losers in baseline age, BMI, tobacco use, an d other health status and laboratory measures yielded similar results. CONCLUSIONS: These results indicate that involuntary weight loss occu rred frequently (13.1% annual incidence) in this population of older v eteran outpatients. When involuntary weight loss occurred, the predomi nant anthropometric changes were decrements in measures of centrally d istributed fat (trunkal skinfolds and circumferences). Finally, involu ntary weight loss greater than 4% of body weight appears to be clinica lly important as an independent predictor of increased mortality.