Night Eating Syndrome (NES) in a severely obese UK population: prevalence and relationship with sleep.

Introduction: The prevalence of NES and its relationship with poor sleep quality and obesity-related co-morbidity in a severely obese UK clinic population is unknown. This work employed validated tools to identify prevalence and explore this relationship. Methods: Consecutive clinic attendees (n=103, mean BMI 47.0 (9.8) kg/m2, age 44.4 (11.9) years, 72% female), completed the Pittsburgh Sleep Quality Index (PSQI) to identify sleep quality. The Night Eating Questionnaire (NEQ) and Epworth Sleepiness Score (ESS) were also completed to identify suspected NES and Obstructive Sleep Apnoea (OSA) respectively. Proportions of individuals above and below tool cut-points were compared using: NEQ lower cut -point of >25 and higher cut >30; PSQI cut > 5; ESS cut >10. Pearson correlation coefficients examined relationships between tool scores. Results: NES was suspected in 14.6% using the lower cut-point, and 3.9% using the higher cut-point. Poor sleep quality was noted in 74% and suspected OSA in 32%. The strongest correlation between PSQI and NEQ total scores (r=0.55, p