ORIGINAL ARTICLE Journal of the College of Physicians and Surgeons Pakistan 2020, Vol. 30(08): 833-838 833 Night Eating Syndrome According to Obesity Groups and the Related Factors Yasin Kara, Sabah Tuzun, Can Oner and Engin Ersin Simsek Department of Family Medicine, University of Health Sciences, Istanbul Kartal Dr. Lutfi Kirdar Training and Research Hospital, Istanbul, Turkey ABSTRACT Objective: To find the frequency of night eating syndrome (NES) in different obesity groups and to determine related factors. Study Design: Descriptive cross-sectional study. Place and Duration of Study: Department of Family Medicine, Outpatient Clinics, University of Health Sciences, Kartal Dr. Lutfi Kirdar Training and Research Hospital from December 2018 to January 2019. Methodology: Participants were divided into class I, class II, and class III obesity groups according to their BMI levels and administered a survey evaluating their sociodemographic features and a NES questionnaire. Results: NES was detected in 92 (21.85%) of all participants; whereas, 28 participants (18.67%) of class I obesity group, 32 participants (22.70%) of class II obesity group and 32 participants (24.62%) of class III obesity group had NES (p=0.465). There was no significant difference between individuals with and without NES in terms of age, gender, marital status, income level, occupational status, presence of children, living-together subjects, cigarette consumption, BMI, waist-hip ratio, and waist-height ratio. However, within the class I obesity group, the likelihood of weight loss was significantly lower among participants with NES (p=0.026). There was no relationship between NES and the duration of obesity, dieting, and the number of main meals per day. However, the relationship between NES and the number of snacks per day was significant in class I and III obesity groups (p=0.040 and p=0.034, respectively). Conclusion: The frequency of NES was found to be high in all obesity groups with no significant difference across groups. There- fore, all obese patients should be evaluated in terms of NES, and nutritional recommendations should be provided in the treat- ment of obesity. Key Words: Morbid obesity, Night eating syndrome, Obesity. How to cite this article: Kara Y, Tuzun S, Oner C, Simsek EE. Night Eating Syndrome According to Obesity Groups and the Related Factors. J Coll Physicians Surg Pak 2020; 30(08):833-838. INTRODUCTION Night eating syndrome (NES) was first defined in 1955 as the lackofappetiteinthemorning,hyperphagiaintheevening,and difficulty in falling asleep and maintaining sleep in obese people, who do not respond to the treatment as requested. 1,2 It has been found that disturbance between the sleep and eating patterns as well as shifts in the biological hour of eating occurred in individuals diagnosed with NES. 3,4 Delays in meal- timesandwakingupatnighttoeatmaycauselossofappetitein breakfast. 2 The rhythm between eating and sleeping is delayed for between two and six hours in patients with NES. 3 Correspondence to: Dr. Yasin Kara, Department of Family Medicine, University of Health Sciences, Istanbul Kartal Dr. Lutfi Kirdar Training and Research Hospital, Istanbul, Turkey E-mail: dryasnkara@gmail.com ..................................................... Received: November 27, 2019; Revised: July 17, 2020; Accepted: July 27, 2020 DOI: https://doi.org/10.29271/jcpsp.2020.08.833 Although there are studies showing association with the pres- ence of NES and obesity, 1,2,5-7 there are also studies demons- trating the contrary. 4,8 In addition, the prevalence of NES varies widely due to the lack of a consensus in diagnostic criteria. 1 The prevalence of NES in healthy adults is between 0.5-1.5%, while this rate varies between 8.9-14% in obese individuals. 1 Obesity has become the disease of the current era due to wide adoption of passive lifestyles and incorrect eating habits. Prior research has not conclusively identified the relationship between obesity and NES vis-à-vis underlying factors. Any new insights will contribute to the obesity prevention efforts. The aim of this study was to evaluate NES prevalence across obesity groups and to determine the variation of socio-demo- graphic,nutritional,andanthropometricfactorsamongobesity groups in the presence of NES. METHODOLOGY Participants aged above 18 years with a body mass index (BMI) of 30 Kg/m 2 who were admitted to the obesity outpatient clinic, Department of Family Medicine, University of Health Sciences,