Is IGF-1 a marker of cardio-metabolic risk in sleep apnea syndrome (SAS)?

Introduction: Insulin-like growth factor-1 (IGF-1) is the main growth factor associated with growth hormone (GH). IGF-1curbs endothelial function and prevents early atherosclerosis by promoting insulin sensitivity and by preventing postprandial dyslipidemia. Low serum IGF-1 levels have been reported to be associated with SAS and might be one of the mechanisms underlying the increased cardiometabolic risk in SAS. We studied IGF-1 levels in a large prospective cohort of patients referred for suspicion of SAS. Methods: In a multicenter study, serum IGF-1 levels were obtained for 817 patients consulting for suspicion of SAS (SAS confirmed for 567 patients). We analyzed the association between serum IGF-1 level below the median value of the general population and variables related to cardiometabolic risk: BMI, apnea hypopnea index (AHI), cholesterol and triglycerides (TG). Results: In our cohort, IGF-1 level below the median (138 ng/ml) was associated with increased BMI and AHI (respectively OR = 2.83; p Conclusion: There is a relationship between low levels of IGF-1 and predictors of cardiovascular risk in SAS. IGF-1 is a potential prognostic biomarker in SAS patients. Our results also provide insights regarding the mechanisms of co-morbidities in these patients.