Objectives: The aim of this study was to examine the direct impact of higher body mass index on the incidence of sleep-disordered breathing. Study design: cross-sectional study with historical data Respondents and methods: An anonymous survey was used for collecting demographic and clinical data from patients treated at the Clinic for otorhinolaryngology and head and neck surgery of the University Hospital Center Osijek from January 2018 to January 2020. Results: Out of 219 patients who participated in the study, 63.5 % were women and 36.5 % were men. The most common sleep disorder was snoring (46.6 %). Of that, 28.8 % of patients were of normal body weight, 56.9 % were overweight, and 75.5 % were obese. The study found a difference between sexes, where twice as many women suffered from restless legs syndrome (33,1 %) and arrhythmias (23 %) than men did. Out of the 102 patients affected by snoring, there were twice as many men (61.3 %) in comparison to women (38,4 %). Out of the 22 patients affected by apnea, there were more men ( 17,5 %) than women (5,8 %). Conclusion: A correlation between a higher body mass index and snoring as a sleep-disordered breathing was observed. A correlation was not observed between BMI and the incidence of obstructive sleep apnea, insomnia, somnambulism, restless legs syndrome, and arrhythmias. The incidence of snoring and apnea is twice as high in men than in women. Restless legs syndrome and arrhythmias are more common in women. Keywords: apnea, arrhythmia, body mass index, insomnia, obesity, restless legs syndrome, snoring, somnambulism