Table 3.

Hazard ratios (HR) and 95% confidence intervals (CI) for all-cause mortality according to body mass index, stratified by age at time of diagnosis

	N	All-cause mortalitya
		HR	95% CI	p value for trend
Under 50 years of age (N= 1637)
Body mass index (kg/m2)
< 18.5	26	0.10	0.01–0.85
18.5–24.9	585	1 (ref)
25–29.9	408	0.94	0.59–1.51
30–34.9	306	0.89	0.54–1.46
≥ 35	312	1.04	0.63–1.73
per 5 kg/m2 Δ		1.01	0.91–1.13	0.79
50–69 years of age (N = 2541)
Body mass index (kg/m2)
< 18.5	26	1.05	0.36–3.04
18.5–24.9	651	1 (ref)
25–29.9	773	0.82	0.57–1.19
30–34.9	581	0.77	0.52–1.13
≥ 35	510	0.84	0.56–1.28
Per 5 kg/m2 Δ		0.95	0.86–1.05	0.30
70 years of age or older (N = 1201)
Body mass index (kg/m2)
< 18.5	25	1.92	1.11–3.34
18.5–24.9	381	1 (ref)
25–29.9	414	0.84	0.63–1.14
30–34.9	239	0.73	0.51–1.05
≥ 35	142	0.78	0.52–1.17
per 5 kg/m2 Δ		0.85	0.75–0.95	0.01

p value for interaction term (age*BMI) = 0.01

^aModels adjusted for AJCC stage, insurance type, poverty in census tract of residence, education levels in census tract of residence, urbanicity of residence area, tumor grade, hormone receptor status, and comorbidity level. Survey sampling was stratified by tumor registry and by race/ethnicity