Table 1.

Results from Cox proportional hazards models

	Activity-Sleep				Rhythmicity-Sleep
Variable	HR	[95% CI]	Wald χ2	P	HR	[95% CI]	Wald χ2	P
Alcohol
Ever tried	1.11	[1.02, 1.21]	5.84	.016	0.95	[0.87, 1.03]	1.56	.21
Disorder	1.03	[0.89, 1.19]	0.15	.69	0.82	[0.71, 0.95]	6.67	.01
Cannabis
Ever tried	1.13	[1.02, 1.24]	5.31	.021	0.96	[0.87, 1.06]	0.71	.39
Disorder	1.15	[0.98, 1.34]	3.08	.079	0.88	[0.75, 1.02]	2.76	.097
Cocaine
Ever tried	1.09	[0.86, 1.40]	0.51	.48	0.95	[0.74, 1.22]	0.19	.66
Disorder	0.97	[0.70, 1.35]	0.03	.86	0.72	[0.51, 1.01]	3.71	.054
Depressive
Disorder	1 .23	[1.06, 1.42]	7.43	.006	0.96	[0.83, 1.11]	0.32	.57

Notes: HR = hazard ratio; CI = confidence interval. All models included sex, age at Visit 1, race, and the presence of parental substance use disorder as covariates. We also explored interactions between the sleep predictors and other covariates, but no interactions were statistically significant.