Study objective: We hypothesized that the sleep complaints of insomnia predict incident hypertension, particularly in African Americans. The purpose of this study was to analyze insomnia complaints as predictors of incident hypertension in the Cardiovascular Health Study (CHS), stratifying by gender and allowing for race and sleep variable interaction.
Design: This is a prospective cohort study over a 6-year period of follow-up.
Setting: This is a community-based study of participants in Forsyth County, North Carolina; Pittsburgh, Pennsylvania; Sacramento County, California; and Washington County, Maryland.
Participants: The study analyzed data from 1419 older individuals (baseline mean age 73.4 +/- 4.4 years) from the Cardiovascular Health Study who were not hypertensive at baseline.
Measurements: We constructed relative risks of incident hypertension over a 6-year period for insomnia complaints singly and in combination.
Results: Difficulty falling asleep, singly or in combination with other sleep complaints, predicted a statistically significant reduction of risk for incident hypertension for non-African American men in 6 years of follow-up. Insomnia complaints did not predict incident hypertension in 6 years of follow-up in women or in African Americans, although there may not have been enough power to show a significant association for African Americans.
Conclusions: Insomnia did not predict hypertension in this older cohort which was free of hypertension at baseline. Difficulty falling asleep was associated with reduced risk of hypertension in non-African American men.