The Prevalence of Metabolic Syndrome in First Degree Relatives of Patients with Obstructive Sleep Apnea Syndrome: A Case–Control Study

BACKGROUND: There was the association between the metabolic syndrome (MS) and obstructive sleep apnea (OSA). Also, the genetic factors have been implicated in the OSA. Our aim was to compare the frequency of MS in first-degree relatives (FDRs) of OSA patients with healthy controls. METHODS: 39 FDR (parents, siblings, and children) of patients diagnosed with OSA at Bamdad Respiratory and Research Center as cases and age- and sex-matched healthy controls were included in the current case–control pilot study. The sampling method was convenience sampling based on having inclusion criteria and consent to participate in the study. Demographic characteristics and essential criteria for diagnosing MS included blood pressure, anthropometric [weight (kg), height (cm), waist circumference (cm) and body mass index (BMI) (kg/m(2))], and biochemical indices (lipid profile and blood glucose) were assessed based on standard protocols. RESULTS: In the comparison of the demographic and clinical characteristics of two39 cases and control groups, weight and diastolic blood pressure were significantly higher in case group than controls (P < 0.05). Case and control groups were not significantly different in the frequency of MS (P > 0.05). Although, the frequency of hypertension as an important cardiovascular risk factor was higher in cases than controls (P < 0.05). CONCLUSIONS: The present study demonstrates that the frequency of MS is not significantly different between FDRs of OSA patients and controls. However, further large-scale studies are warranted to detect the frequency of MS in people with hereditary background for OSA compared to general population.