Medical records documentation of constipation preceding Parkinson disease: A case-control study

OBJECTIVE: Parkinson disease (PD) may affect the autonomic nervous system and may cause constipation; however, few studies have explored constipation preceding the motor onset of PD. We investigated constipation preceding PD using a case-control study design in a population-based sample. METHODS: Using the medical records-linkage system of the Rochester Epidemiology Project, we identified 196 subjects who developed PD in Olmsted County, MN, from 1976 through 1995. Each incident case was matched by age (±1 year) and sex to a general population control. We reviewed the complete medical records of cases and controls in the medical records-linkage system to ascertain the occurrence of constipation preceding the onset of PD (or index year). RESULTS: Constipation preceding PD or the index year was more common in cases than in controls (odds ratio [OR] 2.48; 95% confidence interval [CI] 1.49 to 4.11; p = 0.0005). This association remained significant after adjusting for smoking and coffee consumption (ever vs never), and after excluding constipation possibly induced by drugs. In addition, the association remained significant in analyses restricted to constipation documented 20 or more years before the onset of motor symptoms of PD. Although the association was stronger in women than in men and in patients with PD with rest tremor compared with patients with PD without rest tremor, these differences were not significant. CONCLUSIONS: Our findings suggest that constipation occurring as early as 20 or more years before the onset of motor symptoms is associated with an increased risk of Parkinson disease.