Impact of Obesity Degree on Sleep Quality, Physical Activity Level and Excessive Daytime Sleepiness of Patients with Obstructive Sleep Apnea

Keywords

obstructive sleep apnea - obesity - excessive daytime sleepiness

Introduction: Obesity is one of the main causes of Obstructive Sleep Apnea (OSA). A 10% increase in weight predicts an increase of approximately 32% in AHI and a 6-fold greater probability of developing the most severe forms of OSA.

Objective: To analyze the influence of the degree of obesity on sleep quality, level of physical activity, excessive daytime sleepiness and severity of OSA.

Methods: Retrospective cohort study conducted at the sleep physiotherapy outpatient clinic. Data were collected from medical records of patients of both sexes, with OSA, aged ≥18 years and BMI >30 kg/m².Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI) and analysis of polysomnographic variables (AHI and T90%), physical activity level was assessed using the International Physical Activity Questionnaire (IPAQ), and daytime sleepiness was assessed using the Epworth Sleepiness Scale. Patients were divided into groups according to the degree of obesity (grade I, II, or III). Data was obtained from the initial assessment of adaptation to positive pressure therapy. SPSS v.29.0 was used for descriptive analyses, comparative Chi-square analysis, ANOVA analysis of variance, and Pearson correlation, with a significance level of 5%.

Results: Data from 80 individuals (51.2% female; age: 55.90±11.2 years, BMI: 36.38±5.2 kg/m2) were analyzed. Severe OSA was present in 68.8% of the individuals. Obesity grades I, II and III followed the proportions of 51.2%, 31.3% and 17.5%. According to the degree of obesity, the following individuals presented poor sleep quality: 90.2% (grade I), 100% (grade II and III). They were classified as sedentary or irregularly active: 78.5% (grade I), 96% (grade II) and 100% (grade III). Excessive daytime sleepiness was presented by 65.9%, 52% and 57.1%, respectively. The AHI and T90% were higher in patients with grade III obesity (AHI: 53.60 ± 25.77; T90%: 153.64 ± 160.86 min) than in patients with grade I obesity (AHI: 34.4 ± 21.6; T90% 73.86 ± 84.37 min) and II obesity (AHI: 34.04 ± 21.26; T90%: 73.37 ± 75.56 min).

Conclusion: According to the degree of obesity, patients presented differences in the perception of sleep quality, daytime sleepiness and level of physical activity. Grade III obesity was associated with a greater perception of poor sleep and higher AHI and T90% values, however, excessive daytime sleepiness was not more prevalent in this group.

No conflict of interest has been declared by the author(s).

Publication History

Article published online:
16 September 2025