SHORT PAPER Impaired subjective sleep quality in irritable bowel syndrome patients with a Type D personality Osman YILDIRIM, 1 Aytekin ALÇELIK, 2 Fatih CANAN, 4 Gülali AKTAS ¸, 2 Mustafa SIT, 3 Ahsen I ˙ S ¸ÇI, 2 Abdullah YALÇIN 2 and Edip E YILMAZ 3 Departments of 1 Psychiatry, 2 Internal Medicine and 3 Surgery, School of Medicine, Abant Izzet Baysal University, and 4 Psychiatry Clinic, Bolu Izzet Baysal Mental Health Hospital, Bolu, Turkey Abstract We aimed to assess the effect of Type D personality on subjective sleep quality in patients with irritable bowel syndrome (IBS). Ninety-seven patients and 39 healthy controls were enrolled. The Type D Scale (DS14), Pittsburgh Sleep Quality Index (PSQI), and Hospital Anxiety and Depression Scale were used. IBS patients with a Type D personality were found to score higher on sleep latency, sleep disturbance, and global sleep quality domains of PSQI than patients without a Type D personality. Poor sleeping was more prevalent among patients with a Type D personality than those without (50.0% vs 33.9%; P < 0.01). Key words: irritable bowel syndrome, sleep quality, Type D personality. INTRODUCTION Many studies have demonstrated the role of psychoso- cial and behavioral risk factors in the etiology, patho- genesis, and course of irritable bowel syndrome (IBS). Patients with IBS have increased psychiatric comorbid- ity. These contribute to impairments in quality of life and excessive use of health care associated with IBS. IBS was also reported to be related to poor sleep quality. 1 The Type D personality (TDP) is defined as the co-occurrence of negative affect (NA) and social inhibi- tion (SI). 2 NA refers to a tendency to experience negative emotions such as hostility, depression, and anger across time and situations. SI connotes the tendency to hold back the expression of these emotions in social interac- tion due to fears of rejection or disapproval by others. Type D patients are reported to experience decreased levels of social support and to be less likely to engage in positive health-related behavior. 2 TDP has been receiv- ing a lot of attention as an important indicator of adverse clinical outcome not only in cardiac patients, 3 but also in patients without cardiovascular disease. We aimed to assess the prevalence of TDP in patients with IBS in comparison with healthy volunteers. Our second objective was to investigate whether the pres- ence of TDP would affect subjective sleep quality in patients with IBS. METHODS Ninety-seven consecutive IBS patients and 39 healthy volunteers participated in the study. Patients were included only if they had been diagnosed with IBS in accordance with the Rome III criteria for at least 1 year. Patients were additionally screened to rule out organic bowel diseases and psychiatric conditions. Additional exclusion criteria were major surgery in the past 5 years and diabetes. All controls were screened for similar exclusion factors. Healthy controls were selected from the community or staff members of the institute exclud- ing those fulfilling for IBS on enquiry. The study Correspondence: Dr Osman Yıldırım, Department of Psychiatry, Abant Izzet Baysal University School of Medicine, 14280, Bolu, Turkey. Email: drosman74@hotmail.com Accepted 6 December 2012. Sleep and Biological Rhythms 2013; 11: 135–138 doi:10.1111/sbr.12005 135 © 2013 The Authors Sleep and Biological Rhythms © 2013 Japanese Society of Sleep Research