TABLE 5.

Hazard ratios and 95 percent confidence intervals for cardiovascular disease mortality in three US mortality studies

	Framingham	NHANES	NHIS
Main effects (earlier period)	Original cohort 1948–1970	NHANES I 1971–1987	Period 1 1987–1996
Underweight (BMI<18.5)	0.54 [0.08–3.87]	1.79* [1.08–2.98]	1.25 [0.98–1.59]
Normal weight (18.5–24.9)	1.00 [Ref.]	1.00 [Ref.]	1.00 [Ref.]
Overweight (25.0–29.9)	1.00 [0.80–1.25]	0.83* [0.65–1.05]	0.97 [0.88–1.08]
Class I obese (30.0–34.9)	1.53** [1.14–2.04]	1.82*** [1.30–2.55]	1.40*** [1.23–1.59]
Class II/III obese (35.0+)	2.13** [1.34–3.39]	1.68* [1.05–2.69]	1.80*** [1.47–2.21]
Interaction effects
Underweight × period	5.53 [0.33–92.97]	0.74 [0.30–1.79]	0.80 [0.46–1.38]
Overweight × period	1.17 [0.67–2.07]	1.19 [0.86–1.65]	0.94 [0.79–1.12]
Class I obese × period	0.83 [0.42–1.66]	0.65* [0.42–1.00]	0.83 [0.68–1.01]
Class II/III obese × period	1.17 [0.46–2.99]	0.88 [0.48–1.61]	0.96 [0.69–1.32]
Main × interaction effects (later period)	Offspring cohort 1985–2003	NHANES III 1988–2006	Period 2 1997–2006
Underweight (BMI<18.5)	2.99 [0.40–22.52]	1.32** [0.64–2.73]	0.99 [0.61–1.63]
Normal weight (18.5–24.9)	1.00 [Ref.]	1.00 [Ref.]	1.00 [Ref.]
Overweight (25.0–29.9)	1.18 [0.70–1.98]	0.98 [0.79–1.22]	0.91 [0.79–1.05]
Class I obese (30.0–34.9)	1.28 [0.69–2.38]	1.18 [0.89–1.55]	1.15 [0.99–1.35]
Class II/III obese (35.0+)	2.48* [1.10–5.61]	1.49 [1.02–2.16]	1.73*** [1.35–2.22]

^*p<.05

^**p<.01

^***p<.001

NOTE: All models adjust for sex, cigarette smoking, and education. The NHANES and NHIS analyses are further adjusted for family income, race/ethnicity, marital status, and US region of residence. Dates refer to time span of the mortality period. Main effects indicate hazard ratios for the earlier period of each data source. Hazard ratios for later period were obtained by multiplying the main effects by the interaction effects (may not be exact because of rounding).