Introduction: Obesity has a wide range of negative health effects.1 We aimed to assess whether obesity is also associated with excessive daytime sleepiness (EDS), a predictor of high mortality and morbidity.2,3
Methods: 707 participants of the Global Corporate Challenge® Evaluation Study,4,5 an evaluation of a four-month workplace pedometer program in Melbourne, Australia, were assessed for EDS using the Epworth Sleepiness Scale (ESS). The ESS score ranges from 0 to 24, with higher score reflecting higher level of daytime sleepiness, and EDS categorised as ESS score>10. The association between obesity and EDS was analysed using multiple linear and logistic regression models, with each of the model adjusted for workplace clustering effects and potentially relevant co-factors such as demographics, diet, behavioural, psychosocial, anthropometric and biomedical factors.
Results: In this study population of Australian employees with mixed occupations (mean age 40.2±10.4 years, 40.0% males, mean BMI 26.7±4.8 kg/m2) the prevalence of EDS was 16.0%. In the multiple linear regression model, study participants who were overweight (38.3%) and obese (19.7%) were found to have significantly higher(worse) ESS scores (overweight: +0.84(95%CI 0.07 to1.61 unit), obese: +1.13(95%CI 0.12 to 2.14 unit)) than those with normal weight. In the multiple logistic regression model, being in the obese category was not associated with EDS, but being overweight increased the odds of EDS by 1.8 times (95%CI 1.0 to 3.1) when compared to having normal weight.
Conclusion/recommendation: Our result suggests that obesity is associated with an increased risk of EDS. This may represent an important pathway between obesity and increased risk of accidents, injuries and loss of productivity. Further study may assess whether this association is causal and whether weight-loss programs may lead to improvement in EDS.