Loud Snoring, Insomnia Symptoms Linked to Risk for Metabolic Syndrome
December 3, 2010 — Loud snoring, difficulty falling asleep, and “unrefreshing” sleep may each predict development of the metabolic syndrome, according to the results of a prospective study reported in the December 1 issue of Sleep.
“This is the first prospective study to show that a broader array of commonly reported sleep symptoms, including insomnia and sleep-disordered breathing symptoms, predict the development of the metabolic syndrome, a key risk factor for cardiovascular disease,” said lead author Wendy M. Troxel, PhD, assistant professor of psychiatry and psychology at the University of Pittsburgh in Pittsburgh, Pennsylvania, in a news release. “It was rather striking that the effects of difficulty falling asleep and loud snoring were largely independent of one another.”
The study sample consisted of 812 participants in the community-based Heart Strategies Concentrating on Risk Evaluation study who were free of metabolic syndrome or diabetes at baseline, who had completed a baseline sleep questionnaire (including the Insomnia Symptom Questionnaire and the Multivariable Apnea Prediction Questionnaire), and who were assessed for metabolic syndrome 3 years after baseline. Two thirds of participants were women, and 36% were African American.
A subset of 290 participants underwent cross-sectional determination of the apnea-hypopnea index (AHI) using a portable monitor. The risk for the development of metabolic syndrome and its components was calculated for insomnia syndrome as well as for individual insomnia symptoms with use of logistic regression.
During 3-year follow-up, metabolic syndrome was diagnosed in 14% of participants (n = 115). Significant predictors of development of the metabolic syndrome were difficulty falling asleep (DFA; odds ratio