Sleep problems particularly to loud snoring linked to metabolic syndrome including metabolic abnormalities of hyperglycemia and low levels of high-density lipoprotein cholesterol Professional Medicine

Sleep problems particularly to loud snoring linked to metabolic syndrome including metabolic abnormalities of hyperglycemia and low levels of high-density lipoprotein cholesterol

December 2, 2010, 8:11 pm

Adults with having sleep problems, insomnia, and particularly loud snoring should be aware that those symptoms associated with metabolic syndrome and can leads to cardiovascular risk in future.

According to new findings that published on December 1, 2010 in Sleep, loud snoring was linked to more than twice the risk of the metabolic syndrome developing, and also with the specific metabolic abnormalities of hyperglycemia and low levels of high-density lipoprotein cholesterol.

As the metabolic syndrome is key factor for cardiovascular risk, the researchers suggested that evaluating sleep problems can help identify individuals at risk for developing metabolic syndrome.

The lead author of the study, an assistant professor of psychiatry and psychology at the University of Pittsburgh in Pittsburg, Pennsylvania, Wendy M. Troxe, PhD, said in news release, “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.”

According to Dr. Troxe, it was rather striking that the effects of difficulty falling asleep and loud snoring were largely independent of one another.

The study itself involved 812 participants in the community-based Heart Strategies Concentrating on Risk Evaluation study who were free of metabolic syndrome or diabetes at baseline. Among those participants, two third were women, and 36% were African American. All of them had completed a baseline sleep questionnaire (including the Insomnia Symptoms Questionnaire and the Multivariable Apnea Prediction Questionnaire), and were assessed for metabolic syndrome 3 years after baseline.

Some of subjects (290 participants) underwent cross-sectional determination of apnea-hypopnea index (AHI) using a portable monitor. The risk for the development of metabolic syndrome and its component was calculated for insomnia syndrome as well as for individual insomnia symptoms with use of logistic regression.

The researchers found that during 3-years follow-up, 14% of subjects (115 participants) diagnosed with metabolic syndrome. The grade level the risk of the metabolic syndrome developing were; – difficulty falling asleep (DFA) with the odds ratio (OR) 1.81 (most significant predictor of metabolic syndrome development), – unrefreshing sleep (but not a syndromal definition of insomnia) with OR 1.71, and – difficulty staying asleep and frequent awakening from sleep.

Overall, according to the authors, even after adjustment for AHI with odds ration 3.01 or for the number of baseline metabolic abnormalities, loud snoring remained a significant predictor of metabolic syndrome. However, the predictive value of DFA and unrefreshing sleep were only marginally significant after this adjustment. For logistic regression, it shows that both loud snoring and DFA remained significant independent predictors of the metabolic syndrome.

Despite the study have several limitations such as AHI assessed in a relatively small subsample of the study cohort and AHI determined via nasal airflow, also lacked a direct measure of intermittent hypoxemia, a measure of sleep duration, and objective measures of sleep disturbances, the authors conclude, “To better understand the putative mechanisms linking sleep disturbances with cardiovascular risk, future prospective studies should examine the combination of subjective sleep complaints in conjunction with physiological indicators of poor sleep in relation to cardiovascular morbidity and mortality.”

Giving that in the general population, sleep complaints are considerably more prevalent than either insomnia or obstructive sleep apnea syndromes, according to the authors, these findings have far-reaching implications for public health, particularly given epidemic levels of obesity and its associated cardiometabolic consequences, which are associated with sleep disturbances.

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