Table 3. Odds Ratio (95% CI) of incident hypertension at phase 7 (2002-2003) across categories of sleep duration at phase 5 (1997-1999). The Whitehall II study (n=3,691).

Sample Models	Sleep duration (hours)													p-value *
	<=5			6			7	8			9+			Linear	Non-linear
	Male (n=2,686)
No	n=160			n=900			n=1,224	n=372			n=30
Cases	n=29			n=179			n=243	n=85			n=3
Model 1 ‡	0.89	0.58	1.37	1.00	0.81	1.24	1	1.20	0.90	1.58	0.45	0.13	1.49	0.60	0.53
Model 2 §	0.96	0.62	1.48	1.07	0.86	1.34	1	1.07	0.80	1.42	0.36	0.11	1.19	0.51	0.42
Model 3 #	0.89	0.55	1.43	1.02	0.80	1.31	1	1.11	0.80	1.53	0.13 †	0.02	0.98	0.55	0.18
	Female (n=1,005)
No	n=75			n=330			n=394	n=186			n=20
Cases	n=20			n=77			n=64	n=37			n=3
Model 1 ‡	1.88 †	1.05	3.34	1.56 †	1.08	2.27	1	1.28	0.82	2.01	0.91	0.26	3.20	0.029 †	0.38
Model 2 §	1.94 †	1.08	3.50	1.56 †	1.07	2.27	1	1.17	0.74	1.86	0.92	0.26	3.27	0.015 †	0.42
Model 3 #	1.31	0.65	2.63	1.42	0.93	2.16	1	0.99	0.59	1.69	1.07	0.29	3.94	0.12	0.61

^*p value for test of linear and nonlinear trends.

^†p<0.05.

^‡Model 1: unadjusted.

^§Model 2: adjusted for age and employment.

^#Model 3: Model 2 + alcohol consumption, smoking, physical activity, BMI, SF36 Mental, SF36 Physical, depression cases, hypnotics use, CVD drugs