Abstract. Elmasry A, Janson C, Lindberg E, Gislason T, Tageldin MA, Boman G (Uppsala University, Akademiska Sjukhuset, Uppsala, Sweden; Ain Shams University, Cairo, Egypt; and Viffilsstadir Hospital, Gardabñr, Iceland). The role of habitual snoring and obesity in the development of diabetes: a 10-year follow-up study in a male population. J Intern Med 2000; 248: 13±20.Objectives. There are many similarities between diabetes (mainly type 2) and sleep breathing disturbances regarding risk factors, anthropometric criteria and consequences of morbidity and mortality. The aim of this study was to investigate whether the association between habitual snoring and diabetes is entirely dependent on obesity. Design. A population-based prospective study. Setting. The municipality of Uppsala, Sweden. Subjects and methods. In 1984 and in 1994, 2668 men aged 30±69 years at baseline answered questionnaires concerning sleep breathing disturbances and somatic diseases.Results. Of those with habitual snoring in 1984, 5.4% reported that they had developed diabetes during the 10-year period compared with 2.4% of those without habitual snoring (P , 0.001). Amongst obese snorers, 13.5% developed diabetes compared with 8.6% of obese non-snorers (P = 0.17). In a multiple logistic regression model, the odds ratio (95% confidence interval) for development of diabetes was higher in obese snorers [7.0 (2.9±16.9)] than in obese non-snorers [5.1 (2.7±9.5)] after adjustment for age, weight gain, smoking, alcohol dependence and physical inactivity. Conclusions. We conclude that, in males aged 30± 69 years, habitual snoring is associated with an increased incidence of diabetes within 10 years. Although obesity is the main risk factor for developing diabetes, coexistent habitual snoring may add to this hazard.