Table 3.

Relative risks of incident essential tremor according to habitual sleep duration at baseline

Sleep duration (hours per day)
	≤5 (n = 355)	6 (n = 416)	7–8 (n = 1,168)	≥9 (n = 1,364)
Unadjusted
Relative risk	2.25	1.46	1	0.74
95% CI	1.21–4.16	0.75–2.85		0.41–1.32
p value	0.01	0.27		0.31
Adjusted (Model 1) *
Relative risk	1.99	1.46	1	0.71
95% CI	1.06–3.74	0.74–2.85		0.40–1.28
p value	0.03	0.27		0.26
Adjusted (Model 2) **
Relative risk	1.95	1.45	1	0.69
95% CI	1.03–3.70	0.74–2.84		0.38–1.26
p value	0.04	0.28		0.23

^*Adjusted for depressive symptoms or antidepressant use (variable associated both with sleep duration categories and essential tremor).

^**Adjusted for age, gender, educational level, current smoker, current drinker, and depressive symptoms or antidepressant use (variables associated with either sleep duration categories or essential tremor).