Prevalence and risk factors of functional constipation in the Rome IV criteria during a medical check‐up in Japan

Background and Aim Functional constipation (FC) is one of the functional bowel disorders with symptoms of constipation in the Rome IV criteria. This study aimed to examine the epidemiology of FC in a large‐scale survey of individuals undergoing a medical check‐up in Japan. Methods A total of 13 729 subjects who underwent a medical check‐up at MedCity21 between April 2018 and March 2019 were given a questionnaire that inquired about bowel habits. Among them, 10 658 subjects participated in this study, and FC was diagnosed based on the Rome IV criteria. Results The number of subjects who fulfilled diagnostic criteria of FC was 220, and the prevalence of FC was 2.1%. Compared with subjects with non‐FC, those with FC were more complaining of abdominal bloating and distension, feeling stressed, getting annoyed, lack of motivation, fatigue upon waking, and feeling depressed. The risk of FC was significantly lower among subjects who drank alcohol more than 5 days a week, exercised for more than 30 min at least twice a week for more than 1 year, and were getting enough rest by sleeping, whereas it was significantly higher among women and subjects who were eating faster than other people. Conclusions The prevalence of FC in Japanese subjects during a medical check‐up was relatively low compared with that in Western countries. Subjects with FC had troublesome symptoms, and it might be suggested that female sex, lack of regular exercise with moderate activity, insufficient rest by sleeping, and eating faster were a risk of FC.