- The normal aging process is not in itself a risk factor for constipation, but age-related morbidities, immobility, neurologic impairment or specific drugs are risk factors for constipation. This study was undertaken to examine the prevalence and risk factors for constipation in a large sample of 2400 persons with intellectual disability (ID) aged 40 years and older living in residential care centers in Israel. Constipation was found in 8% of the total sample with no significant increase in the prevalence of constipation with age. Neurological disease, cerebral palsy, immobility and physical inactivity were risk factors associated with constipation. Mobility and physical activity is recommended in order to lower the prevalence of constipation in this population.