Table 4.

Hazard Ratios^a (95% Confidence Intervals) of Death by Reported Nighttime Sleep Duration and Afternoon Nap Duration, Stratified by Sex

Nap duration (In minutes)	Hours of nighttime sleep
	<7	7 – 7.9	8 – 8.9	9 – 9.9	≥10
Male
No	1.00	1.00	1.00	1.00	1.00
<60	0.64 (0.28–1.47)	0.68 (0.37–1.25)	0.82 (0.51–1.33)	1.06 (0.54–2.11)	0.48 (0.23–1.02)
60–89	0.97 (0.56–1.67)	1.06 (0.72–1.55)	0.90 (0.65–1.25)	1.27 (0.86–1.89)	0.69 (0.40–1.17)
90–119	0.96 (0.46–2.03)	0.98 (0.60–1.61)	0.91 (0.55–1.49)	1.08 (0.60–1.94)	0.69 (0.37–1.28)
120 and over	1.15 (0.61–2.18)	1.23 (0.72–2.10)	0.79 (0.50–1.25)	1.33 (0.79–2.23)	1.13 (0.69–1.85)
Female
No	1.00	1.00	1.00	1.00	1.00
<60	0.92 (0.36–2.35)	1.24 (0.51–3.04)	1.58 (0.91–2.75)	0.98 (0.52–1.83)	0.93 (0.47–1.81)
60–89	0.54 (0.22–1.34)	0.76 (0.39–1.50)	1.37 (0.86–2.17)	0.93 (0.58–1.50)	0.96 (0.59–1.58)
90–119	0.19 (0.02–1.46)	0.47 (0.16–1.41)	1.79 (0.88–3.63)	0.96 (0.48–1.90)	1.53 (0.86–2.73)
120 and over	1.75 (0.56–5.43)	1.04 (0.46–2.37)	1.76 (0.99–3.13)	1.20 (0.66–2.20)	1.10 (0.63–1.91)

^aHazard ratios have been adjusted for age at 1993, marital status, monthly income, cigarettes smoking, alcohol consumption, body mass index, exercise, disease history (heart disease, stroke, and cancer), and depression.