Study shows sleep disturbances are common and influenced by race and ethnicity

A new study suggests that sleep disturbances and undiagnosed sleep apnea are common among middle-aged and older adults in the U.S., and these sleep problems occur more frequently among racial/ethnic minorities.

Results show that 34 percent of participants had moderate or severe sleep-disordered breathing measured by polysomnography, and 31 percent had short sleep duration with less than 6 hours per night measured by actigraphy. Validated questionnaires also showed that 23 percent reported having insomnia, and 14 percent reported excessive daytime sleepiness. Only 9 percent of participants reported being told by a doctor that they had sleep apnea.

After adjustment for sex, age, and study site, blacks were most likely to have short sleep duration of less than six hours, and they were more likely than whites to have sleep apnea syndrome, poor sleep quality, and daytime sleepiness. Hispanics and Chinese were more likely than whites to have sleep-disordered breathing and short sleep duration, but Chinese were least likely to report having insomnia.

"Our findings underscore the very high prevalence of undiagnosed sleep disturbances in middle-aged and older adults, and identify racial/ethnic disparities that include differences in short sleep duration, sleep apnea and daytime sleepiness," said lead author Dr. Xiaoli Chen, research fellow in the Department of Epidemiology at Harvard T.H. Chan School of Public Health in Boston.

Study results are published in the June issue of the journal Sleep.

The study population was recruited from six U.S. communities and comprised 2,230 racially/ethnically diverse men and women who were between the ages of 54 and 93 years. Data gathered by polysomnography, actigraphy and validated questionnaires were obtained between 2010 and 2013.

According to Dr. Chen and her colleagues, this is the first study that has comprehensively evaluated objective measures of sleep apnea, short sleep, and poor sleep, as well as subjective measures of habitual snoring, insomnia, and daytime sleepiness in a multi-ethnic U.S. population that includes Chinese Americans. Results suggest that sleep disturbances may contribute to health disparities among U.S. adults.

"As sleep apnea has been implicated as a risk factor for cardiovascular disease, stroke, diabetes, and mortality, our findings highlight the need to consider undiagnosed sleep apnea in middle-aged and older adults, with potential value in developing strategies to screen and improve recognition in groups such as in Chinese and Hispanic populations," said senior author Dr. Susan Redline, professor of medicine at Harvard Medical School and Division of Sleep Medicine at Brigham and Women's Hospital and Beth Israel Deaconess Medical Center in Boston. The study was supported by grants from the National Institutes of Health (NIH) and an award from the National Center for Advancing Translational Sciences (NCATS).