Snoring, hypertension and type 2 diabetes in obesity. Protection by physical activity

ABSTRACT Sleep-related breathing disorders are recognized as major health problems in obesity. They are involved in both hypertension and type 2 diabetes, through mechanism(s) possibly related to increased sympathetic tone. We studied the association of habitual snoring with diabetes, hypertension, weight cycling and physical activity in a large Italian database of treatment-seeking obese subjects. Clinical and behavioural data were assessed by standardized questionnaires. Consecutive data of 1890 obese patients were analysed (average BMI, 38.2 kg/m2, median age 46 years, 78% females), from 25 obesity Italian centres, with low prevalence of clinical manifestations of cardiovascular disease. Habitual snoring was reported in 56% of cases, and was associated with day-time sleepiness. The prevalence increased with obesity class and waist circumference, and was positively associated with weight cycling and weight gain since age 20 years, and smoking. Regular physical activity had a protective effect. Snoring was associated with diabetes and hypertension at univariate analysis, but in multivariate analysis an independent effect was only observed for hypertension. After adjustment for age, gender and BMI, physical activity maintained an independent, protective effect on both snoring (odds ratio 0.65, 95% confidence interval 0.49 – 0.84; P = 0.001), diabetes (0.50, 0.30 – 0.86; P = 0.011) and hypertension (0.71, 0.53 – 0.95; P = 0.023). We conclude that in treatment-seeking, obese subjects with low prevalence of cardiovascular disease, snoring independently increases the risk of hypertension, whereas physical activity exerts a protective on both snoring and complications. These data underline the importance of lifestyle interventions to limit the burden of obesity and associated diseases.