Table 2.

Cross-sectional Linear Multiple Regression Model of BMI (kg/m²) Regressed on Actigraph Sleep Categories (4-Level Ordinal Variable) and Longitudinal Regression Model of BMI Regressed on Actigraph Sleep Categories and BMI 5 Years Prior, the CARDIA Sleep Study, 2000–2006

	Model 1—Cross-sectional			Model 2—Longitudinal
	Coefficient of BMI (kg/m2)	95% Confidence Interval	P Value	Coefficient of BMI (kg/m2)	95% Confidence Interval	P Value
Unadjusted
Sleep (per level)	−1.61	−2.37, −0.86	<0.001	−0.02	−0.30, 0.25	0.86
BMI 5 years prior, kg/m2				1.01	0.96, 1.05	<0.001
Adjusteda
Sleep (per level)	−0.78	−1.55, −0.002	0.05	0.02	−0.27, 0.30	0.91
Age (per year)	0.01	−0.14, 0.16	0.92	−0.01	−0.06, 0.05	0.82
Race-sex groups
White women	Referent			Referent
White men	1.80	0.70, 2.91	0.001	−0.30	−0.72, 0.13	0.17
Black women	4.06	2.38, 5.74	<0.001	−0.21	−0.78, 0.37	0.48
Black men	1.16	−0.64, 2.95	0.21	−0.50	−1.15, 0.16	0.14
Education (per level)	−0.97	−1.51, −0.43	<0.001	−0.29	−0.48, −0.10	0.003
Smoking groups
Nonsmoker	Referent			Referent
Smoker	−1.64	−3.11, −0.17	0.029	−0.13	−0.74, 0.49	0.69
Former smokerb				0.44	−0.30, 1.17	0.24
New smokerb				−3.10	−5.86, −0.33	0.03
Physical activity, exercise units
Current (per 100 units)	−0.30	−0.49, −0.11	0.002	−0.05	−0.14, 0.04	0.25
5 years prior (per 100 units)				0.03	−0.05, 0.12	0.43
Apnea risk
Snoring	3.70	1.93, 5.45	<0.001	0.78	0.13, 1.43	0.02
Tiredness	0.70	−0.47, 1.87	0.24	−0.17	−0.58, 0.23	0.40
BMI 5 years prior, kg/m2				1.00	0.95, 1.04	<0.001

Abbreviations: BMI, body mass index; CARDIA, Coronary Artery Risk Development in Young Adults.

^aIncludes all listed covariates.

^bChanged smoking status between baseline and follow-up.