Symptom-Specific Factors Associated With Chronic Constipation in Older Adults: Cross-Sectional Survey of Patient-Reported Outcomes.

Background: In older adults with chronic constipation, symptoms of defecation difficulty often persist despite improvements in bowel movement frequency. However, constipation-related symptoms have rarely been examined as independent outcomes. Objective: The objective of this study is to explore factors associated with constipation-related symptoms, less than 3 spontaneous bowel movements per week, straining during bowel movements, a sensation of incomplete evacuation, and a sensation of anorectal obstruction or blockage. Methods: A cross-sectional web-based survey was conducted to collect patient-reported data. Constipation-related symptoms were defined according to the Rome IV criteria. Each symptom was treated as a binary variable in the analyses. Multivariable logistic regression analyses were used to examine associations between stool characteristics and medication, treatment processes, and lifestyle-related factors. Stool characteristics were classified using the Bristol Stool Form Scale, with hard stools defined as types 1 and 2. Results: We enrolled 546 participants and investigated the following constipation symptoms: less than 3 spontaneous bowel movements per week (n=226, 41.4%), straining (n=330, 60.4%), sensation of incomplete evacuation (n=344, 63.0%), and sensation of anorectal obstruction or blockage (n=242, 44.3%). Multivariable logistic regression analyses for these outcome variables showed that hard stool was consistently and independently associated with all constipation-related symptoms (odds ratio [OR] 1.86-4.66). Symptom-specific associations that remained significant after false discovery rate adjustment included lower physical activity with less than 3 spontaneous bowel movements per week (OR 0.86, 95% CI 0.77-0.96), stimulant laxative use with the sensation of incomplete evacuation (OR 2.01, 95% CI 1.22-3.31), and lower adherence to the prescribed dosage with the sensation of anorectal obstruction or blockage (OR 0.87, 95% CI 0.78-0.97). In contrast, the experience of adverse effects was associated with a higher probability of less than 3 spontaneous bowel movements per week and the sensation of anorectal obstruction or blockage. Conclusions: In older adults with chronic constipation, different constipation-related symptoms showed distinct patterns of association, while hard stool consistency emerged as a common factor across symptoms. These exploratory findings may support symptom-oriented assessment and help inform individualized management approaches using electronically collected patient-reported outcomes.