Table 5.

Relative Risks of Incident MCI for Changes in Sleep Duration Between First and Second Visit to the Study Center: the Heinz Nixdorf Recall Study^a.

Exposure		RR	95% CI
Change of nocturnal sleep durationb	≤ −1h	1.23	[1.00 to 1.51]
	<−1h to < +1 h	1.00	Reference
	≥ +1 h	0.98	[0.78 to 1.23]
Change of total sleep durationb	≤ −1h	1.26	[1.02 to 1.55]
	<−1h to < +1 h	1.00	Reference
	≥ +1 h	0.92	[0.73 to 1.16]

Estimates of relative risks with 95% confidence intervals were obtained from a log-linear model with a Poisson working likelihood and robust standard errors. RR: Relative Risk; CI: confidence interval. Model is adjusted for age (cont.) and sex (male/female) height (cont.), waist (cont.), Framingham CVD risk score (cont.), smoking status (never/former/current), ISC education years (cont.), physical activity (cont.; meth/week), pure alcohol consumption (cont.; g/week), and depression score (cont.).

^aMultiple imputation was used for analyses

^bSleep differences were calculated subtracting baseline sleeping time from T1 sleeping time.