Body mass index is inversely related to mortality in elderly subjects.
OBJECTIVE
To study the long-term effect of being overweight on mortality in very elderly subjects.


METHODS
The medical records of 470 inpatients (226 males) with a mean age of 81.5 +/- 7 years and hospitalized in an acute geriatric ward between 1999 and 2000 were reviewed for this study. Body mass index (BMI) at admission day was subdivided into quartiles: <22, 22-25, 25.01-28, and > or =28 kg/m(2). Patients were followed-up until August 31, 2004. Mortality data were taken from death certificates.


RESULTS
During a mean follow-up of 3.46 +/- 1.87 years (median 4.2 years [range 1.6 to 5.34 years]), 248 patients died. Those who died had lower baseline BMI than those who survived (24.1 +/- 4.2 vs 26.3 +/- 4.6 kg/m(2); p < .0001). The age-adjusted mortality rate decreased from 24 to 9.6 per 100 patient-years from the highest to lowest BMI quartile (p < .001). BMI was associated with all-cause and cause-specific mortality even after controlling for sex. A multivariate Cox proportional hazards model identified that even after controlling for male gender, age, renal failure, and diabetes mellitus, which increased the risk of all-cause mortality, elevated BMI decreased the all-cause mortality risk.


CONCLUSIONS
In very elderly subjects, elevated BMI was associated with reduced mortality risk.
Weiss
Avraham
A
Geriatric Department, Beilinson Hospital, The Rabin Medical Center, Petach-Tikva, Israel. avrahamw@clalit.org.il
Beloosesky
Yichayaou
Y
Boaz
Mona
M
Yalov
Alexandra
A
Kornowski
Ran
R
Grossman
Ehud
E
D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007557:Israel / Q000453:epidemiology; D008297:Male; D009026:Mortality; D050177:Overweight / Q000401:mortality*; D012189:Retrospective Studies