Constipation in Duchenne Muscular Dystrophy: Prevalence, Diagnosis, and Treatment

ObjectivesTo determine the prevalence and clinical characteristics of constipation among patients with Duchenne muscular dystrophy (DMD).Study designThis cross-sectional prospective study included 120 patients (age range 5-30 years old) with an established diagnosis of DMD. Participants filled out the constipation section of a validated Questionnaire on Pediatric Gastrointestinal Symptoms based on Rome-III Criteria (QPGS-RIII) for the diagnosis of functional constipation as part of a routine clinic visit. We evaluated several potential screening methods for constipation: the Bristol stool form scale, routine physical examination, and fecal load on abdominal radiograph. These methods were compared with the QPGS-RIII in diagnosing functional constipation. Risk factors for the development of functional constipation were determined.ResultsBased on the QPGS-RIII, 46.7% of patients with DMD in this cohort were diagnosed with functional constipation. Prevalence was not affected by age or functional status. None of the screening methods tested were sensitive enough to diagnose functional constipation. Among patients with constipation, only 43.6% received specific treatment for constipation and only one-half of these treated patients reported resolution of constipation.ConclusionsThis study systematically examined constipation among patients with DMD and provides evidence that constipation among patients with DMD is highly prevalent, underdiagnosed, and undertreated. QPGS-RIII is easy to administer and is an efficient tool to diagnose functional constipation in patients with DMD in a clinic setting.