Anthropometric data: A screening tool for severe obstructive sleep apnea in Tunisian population with atrial fibrillation?

Abstract

Obstructive sleep apnea (OSA) is common in patients having atrial fibrillation (AF). Obesity is a key risk factor for the development of OSA and the prevalence of this sleep disordered breathing among obese patients is high (50–98%). The aim of this study was to evaluate correlation between various anthropometric measurements and OSA's severity in patients followed for non valvular AF. It was a prospective study with 100 patients with AF. All patients underwent polygraphy and measures of body mass index (BMI), neck circumference (NC) and waist circumference (WC). Analysis of the sleep study results showed that OSA was present in 90 patients: Severe OSA was diagnosed in 31 patients. The average hypopnea apnea index (AHI) was 21.7 ± 13.6 event/h. The mean BMI was 28.5 ± 4.8 kg/m 2 : 24 patients had normal BMI, 38 were overweight and 29 had moderate obesity. Severe and massive obesity, were noted respectively at 6 and 3 patients. The BMI was significantly associated with severe OSA ( P = 0.041) and the cut-off value for predicting severe OSA was 27.5 kg/m 2 with a sensitivity of 71% and specificity of 50%. The NC was 38.8± 3.9 cm. Forty-five% of the population had truncal obesity. NC was correlated to both AHI ( P = 0.013) and severe OSA ( P = 0.045). The ROC curve indicated that the limit value for predicting severe OSA was 39.5 cm with a sensitivity of 55% and a specificity of 64%. The mean WC was 107.5 ± 12.6 cm. Android obesity was found in 96% of patients. The WC had a significant correlation to both AHI ( P = 0.001) and severe OSA ( P < 0.001). The limit value that orient towards severe OSA was 105.5 cm with sensitivity of 77% and a specificity of 58%. Our study revealed that all anthropometric parameters were associated to severe OSA. NC and WC were found to be correlated to AHI. These findings suggest the importance of routine OSA screening in patients having the association: obesity and AF.