Table 1.

General characteristics of the study participants according to sleep duration and midday napping (N = 11,539)

	Sleep duration, h/night							Midday napping, min
Variables	<6 (n = 549)	6 to <7 (n = 1649)	7 to <8 (n = 4162)	8 to <9 (n = 3666)	≥9 (n = 1513)	F/χ2	P value	0 (n = 6678)	0 to <30 (n = 3104)	30 to <60 (n = 402)	60 to <90 (n = 757)	≥90 (n = 598)	F/χ2	P value
Age, years	62.03 ± 9.14	61.10 ± 9.37	61.14 ± 9.17	61.07 ± 9.58	60.25 ± 10.22	4.31	<0.01	61.18 ± 8.57	65.29 ± 8.46	52.57 ± 9.34	52.85 ± 9.45	53.42 ± 9.24	567.88	<0.01
Male/female	203/346	615/1034	1484/2678	1225/2441	516/997	10.12	0.04	2020/4658	1286/1818	155/247	323/434	259/339	162.56	<0.01
BMI, kg/m2	25.39 ± 3.35	25.40 ± 3.29	25.24 ± 3.34	25.23 ± 3.31	25.08 ± 3.41	2.11	0.08	25.35 ± 3.37	25.62 ± 3.30	24.00 ± 2.96	25.12 ± 3.01	24.37 ± 3.19	58.26	<0.01
Smoking	109	284	673	536	255	13.86	<0.01	1017	559	49	121	111	19.37	<0.01
Drinking	79	246	494	397	187	20.77	<0.01	654	432	64	143	110	103.19	<0.01
Good sleep quality Comorbidities	197	312	512	403	209	286.25	<0.01	5678	2755	316	647	510	42.93	<0.01
Hypertension	142	443	1056	928	372	2.42	0.66	1612	970	73	150	136	87.23	<0.01
Hyperlipidemia	86	186	537	432	185	9.59	0.05	787	515	23	55	46	99.88	<0.01

Data are presented as mean ± SD for continuous variables. BMI: Body mass index; SD: Standard deviation.