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

Background. Cardiovascular disease (CVD) is the leading cause of death among American Indians. It is not known if symptoms of insomnia are associated with CVD in this population. Methods. We examined 449 American Indians aged >= 55 years from the Native Elder Care Study. The main outcome-of-interest was self-reported CVD. Results. Short sleep duration, daytime sleepiness, and difficulty falling asleep were positively associated with CVD after adjusting for demographic, lifestyle, and clinical risk factors. Compared with a sleep duration of 7 h, the multivariable odds ratio (OR) (95% confidence interval [CI]) of CVD among those with sleep duration <= 5 h was 2.89 (1.17-7.16). Similarly, the multivariable OR (95% CI) of CVD was 4.45 (1.85-10.72) and 2.60 (1.25-5.42) for daytime sleepiness >2h and difficulty falling asleep often/always. Conclusion. Symptoms of insomnia including short sleep duration, daytime sleepiness, and difficulty falling asleep are independently associated with CVD in American Indians aged >= 55 years.