ADJUSTED NECK CIRCUMFERENCE AND METABOLIC SYNDROME: RESULTS FROM THE BRISIGHELLA HEART STUDY

Objectives: The association between metabolic syndrome and obstructive sleep apnea (OSA) has long been recognised. Adjusted neck circumference (ANC) is a clinical screening score based on four measures: neck circumference, history of hypertension, snoring and nocturnal choking, which evaluates the probability of OSA (low= ANC<43, intermediate= ≤ 43≤ANC≤48 and high= ANC>48). Our study aims to assess the association between the clinical probability of OSA and the presence of metabolic syndrome. Methods: 1102 subjects (519 males, 583 females) from the 2012 cohort of the Brisighella Heart Study completed ANC screening. Metabolic syndrome was assessed according to the National Cholesterol Education Program Adult Treatment Panel III criteria. Results: 538(48.8%) subjects reported snoring, 90(8.2%) reported sleep apnea or choking. 305(27.7%) had a diagnosis of metabolic syndrome. 774(70.2%) had a low probability of OSA, 238(21.6%) intermediate and 90(8.2%) high. Subjects with an ANC score between 43 and 48 were 1.8 times more likely to have metabolic syndrome than those with a score below 43 (OR=1,841; CI 95%, 1.171-2.894, p=0.008) while for those scoring over 48 the probability was almost 3-fold (OR=2,956; 95% CI, 1.562-5.596, p=0.0009). All results were adjusted for BMI, sex, age and smoking status. ROC curve analysis showed ANC was a better predictor of metabolic syndrome than neck circumference (area under curve 0.726 and 0.690, respectively). Conclusions: A higher clinical probability of OSA is directly associated with the likelihood of metabolic syndrome. ANC is also a useful tool for the diagnosis of metabolic syndrome and is a better predictor than simple neck circumference.