Functional constipation (FC) is a common health problem in children, as evidenced by data from a recent systematic review and meta-analysis on FC (Rome IV); which reported a pooled prevalence of 7 % (IQR; 3.5, 8) in infants, 18.5 % (IQR; 10, 26.5) in children aged 1-4 years, and 12 % (IQR; 4, 14) in children aged more than 4 years. In addition, a recent global survey study showed that FC accounts for overall 30% of patients attending pediatric gastroenterology clinics, worldwide. Epidemiological studies suggest that the prevalence of FC in Asia is significantly lower than other geographic regions. There have been studies demonstrating that, when using the same method of study, the prevalence of FC according to Rome III and Rome IV criteria in children aged > 4 years were comparable. There have been no conclusive evidence to support the association between FC with factors including gender, obesity, familial socioeconomic status, and exposure to stressful life events. However, it seems that history of FC in family, life style (diet and physical activity) are risk factors for childhood FC.
FC in children has a long clinical course. Only 50% of constipated children recover at one- year follow-up. About 20 % of children have persistence of FC into young adulthood. To date, studies concerning factors of influence on treatment outcomes of childhood FC have shown conflicting results. Therefore, it is needed that a good quality long term follow- up study, to determine predictive factors in regards to the clinical course of FC in children, takes place.