Neck circumference, metabolic syndrome and obstructive sleep apnea syndrome; evaluation of possible linkage.

BACKGROUND: This study was performed to evaluate neck circumference (NC) and metabolic syndrome (MS) parameters in severe and non-severe (mild-moderate) obstructive sleep apnea syndrome (OSAS) patients according to apnea-hypopnea index (AHI).

MATERIAL AND METHODS: We enrolled 44 patients diagnosed with OSAS based on overnight polysomnography. The diagnosis of OSAS was based on AHI. Apnea is a pause of airflow for more than 10 seconds. and hypopnea is a decrease of airflow for more than 10 seconds and oxygen desaturation of 4% or greater. AHI score. per hour; below 5 normal. 5-29 mild-moderate. 30 and above were grouped as severe OSAS. Height. weight. neck circumference (NC). waist circumference (WC) and body mass index (BMI) of the patients were measured. MS was diagnosed by the Adult Treatment Panel (ATP) III criteria (≥3 of the following abnormalities): 1) WC ≥94 cm for males, ≥80 cm for females; 2) arterial blood pressure ≥130/85 mmHg; 3) fasting blood glucose ≥100 mg/dl; 4) high density lipoprotein (HDL) cholesterol <40 mg/dl in man, <50 mg/dl in women; 5) triglycerides ≥150 mg/dl.

RESULTS: Mean BMI and NC were higher in severe OSAS patients compared to non-severe patients (p=0.021. p<0.001). According to ATP III criteria. 64% of severe and 61.1% of non-severe OSAS patients were MS (p=0.847). A logistic regression model displayed an association with NC as a risk factor for severe OSAS (p=0.01). but not with MS.

CONCLUSIONS: In this study. NC in severe OSAS patients was significantly higher than in non-severe OSAS patients. The prevalence of metabolic syndrome was not correlated with OSAS severity. NC is an independent risk factor for severe OSAS.