Insomnia Symptoms and Cardiovascular Disease among Older American Indians: The Native Elder Care Study

Table 2

Association between sleep variables and cardiovascular disease.

Sleep variables	No at risk* (𝑛=449)	Weighted prevalence of CVD, %	Age, sex adjusted; OR (95% CI)	Multivariable adjusted; OR (95% CI)^†
Sleep duration, h
≤5	58	29.2	3.51 (1.55–7.95)	2.89 (1.17–7.16)
6	101	17.6	1.55 (0.71–3.42)	1.32 (0.56–3.09)
7	98	12.6	1 (referent)	1 (referent)
8	145	22.1	1.85 (0.89–3.85)	1.67 (0.76–3.66)
≥9	47	18.5	1.46 (0.54–3.93)	1.15 (0.38–3.53)
Frequency of daytime sleepiness, h
1	253	14.3	1 (referent)	1 (referent)
2	161	22.6	1.53 (0.91–2.57)	1.33 (0.76–2.34)
>2	35	54.6	6.06 (2.71–13.52)	4.45 (1.85–10.72)
P-trend			<0.0001	0.003
Difficulty falling asleep
Never	200	14.8	1 (referent)	1 (referent)
Sometimes	178	20.0	1.60 (0.92–2.78)	1.23 (0.68–2.25)
Often or always	71	31.9	3.39 (1.76–6.53)	2.60 (1.25–5.42)
P-trend			0.0004	0.02

Abbreviations: CI: confidence interval; OR: odds ratio.
∗Unweighted sample size
^†Adjusted for age (years), sex (men, women), education (<high school, high school, >high school), current smoking (absent, present), current alcohol consumption (absent, present), physical activity (absent, present), body mass index (kg/m²), diabetes (absent, present), hypertension (absent, present), depression (absent, present), cancer (absent, present), chronic pain (absent, present) and back pain (absent, present).