150 J. Endocrinol. Invest. 27: 150-157, 2004 ABSTRACT. Sleep-related breathing disorders are recognized as major health problems in obe- sity. They are involved in both hypertension and Type 2 diabetes, through mechanisms possibly related to increased sympathetic tone. We stud- ied the association of habitual snoring with dia- betes, hypertension, weight cycling and physical activity in a large Italian database of treatment- seeking obese subjects. Clinical and behavioral data were assessed by standardized question- naires. Consecutive data of 1890 obese patients were analyzed [average body mass index (BMI), 38.2 kg/m 2 , median age: 46 yr, 78% females], from 25 obesity Italian centers, with low prevalence of clinical manifestations of cardiovascular disease. Habitual snoring was reported in 56% of the 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 the age of 20, and smoking. Regular physical activity had a protective effect. Snoring was associated with di- abetes 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 main- tained 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 cardiovas- cular disease, snoring independently increases the risk of hypertension, whereas physical activity ex- erts a protection on both snoring and complica- tions. These data underline the importance of lifestyle interventions to limit the burden of obesity and associated diseases. (J. Endocrinol. Invest. 27: 150-157, 2004) © 2004, Editrice Kurtis INTRODUCTION Obesity is a major threat to public health (1), and complicating diseases contribute to morbidity and mortality. Sleep-related breathing disorders (SRBD) are recognized as major health problems in obesity (2). SRBD range from habitual snoring – a disturbing condition without clinical relevance in less severe cas- es – to sleep apnea syndrome. The majority of pa- tients have excessive daytime sleepiness and tired- ness, which may be a problem at work (3) or driving (4), but far more relevant problems may also ensue. The coexistence of cardiovascular and cerebrovas- cular diseases with sleep-related breathing disorders was long considered the result of shared risk factors, namely ageing, male gender, and obesity (5). In re- cent years several epidemiologic studies have demonstrated that SRBD are independent risk fac- tors for hypertension (6-8), via increased sympa- thoadrenal activity. A link between SRBD and Type 2 diabetes was also suggested (9). This association is also biased by the common occurrence of obesity and hypertension in both conditions, as well as by weight cycling, whose role as a confounder on neg- ative health outcomes, particularly cardiovascular mortality, has never been definitely settled (10, 11). However, it was suggested that sleep apnea might Key-words: Snoring, Diabetes, Non-insulin Dependent, Obesity, Exercise, Weight Gain. Correspondence: Prof. G. Marchesini, Unità di Malattie Metaboliche, Dipartimento di Medicina Interna e Gastroenterologia, Università di Bologna, Policlinico S. Orsola-Malpighi, Via Massarenti, 9. I-40138 Bologna, Italy. E-mail: giulio.marchesini@unibo.it Accepted October 14, 2003. Snoring, hypertension and Type 2 diabetes in obesity. Protection by physical activity G. Marchesini 1 , A. Pontiroli 2 , G. Salvioli 3 , R.F. Novi 4 , E. Vitacolonna 5 , C. Taboga 6 , A.M. Ciccarone 7 , E. Grossi 8 , and the QUOVADIS Study Group* 1 “Alma Mater Studiorum” University of Bologna; 2 University of Milan; 3 University of Modena and Reggio Emilia; 4 University of Turin; 5 University of Chieti; 6 Azienda Ospedaliera di Udine; 7 University of Pisa; 8 Bracco Imaging Spa, Milan *A complete list of participants to the QUOVADIS study group has been published in ref. (18).