Prestroke weight loss is associated with poststroke mortality among men in the Honolulu-Asia Aging Study

Abstract

Objective: To examine baseline prestroke weight loss and poststroke mortality among men.

Design: Longitudinal study of late-life prestroke body mass index (BMI), weight loss, and BMI change (midlife to late life) with up to 8-year incident stroke and mortality follow-up.

Setting: Community-based aging study data.

Participants: Japanese-American men (N=3581; age range, 71-93y) who were stroke free at baseline.

Interventions: Not applicable.

Main outcome measure: Poststroke mortality: 30 days poststroke, analyzed with stepwise multivariable logistic regression; and long-term poststroke (up to 8y), analyzed with stepwise multivariable Cox regression.

Results: Weight loss (4.5kg decrements) was associated with increased 30-day poststroke mortality (adjusted odds ratio=1.48; 95% confidence interval [CI], 1.14-1.92), long-term mortality after incident stroke (all types, n=225; adjusted hazards ratio (aHR)=1.25; 95% CI, 1.09-1.44), and long-term mortality after incident thromboembolic stroke (n=153; aHR=1.19; 95% CI, 1.01 to 1.40). Men with overweight/obese late-life BMI (≥25kg/m(2), compared with healthy/underweight BMI) had increased long-term mortality after incident hemorrhagic stroke (n=54; aHR=2.27; 95% CI, 1.07-4.82). Neither desirable nor excessive BMI reductions (vs no change/increased BMI) were associated with poststroke mortality. In the overall sample (N=3581), nutrition factors associated with increased long-term mortality included the following: (1) weight loss (10lb decrements; aHR=1.15; 95% CI, 1.09-1.21), (2) underweight BMI (vs healthy BMI; aHR=1.76; 95% CI, 1.40-2.20), and (3) both desirable and excessive BMI reductions (vs no change or gain, separate model from weight loss and BMI; aHR range, 1.36-1.97; P<.001).

Conclusions: Although obesity is a risk factor for stroke incidence, prestroke weight loss was associated with increased poststroke (all types and thromboembolic) mortality. Overweight/obese late-life BMI was associated with increased posthemorrhagic stroke mortality. Desirable and excessive BMI reductions were not associated with poststroke mortality. Weight loss, underweight late-life BMI, and any BMI reduction were all associated with increased long-term mortality in the overall sample.

Keywords: Aged; Body mass index; Men; Mortality; Rehabilitation; Stroke; Weight loss.