This study examined 230 patients diagnosed with functional constipation (FC) or constipation-predominant irritable bowel syndrome (IBS-C) using colonic transit tests (CTT), high-resolution anorectal manometry (HR-ARM), and psychological assessments. Though demographic and symptom profiles between the groups were similar, patients with IBS-C showed a higher prevalence of slow colonic transit, while rectosigmoid accumulation (RSARM)—a potential marker of dyssynergic defecation—was more common in FC. Both groups displayed high rates of dyssynergic patterns on HR-ARM, though the specific types differed slightly. Importantly, depression was significantly more prevalent in patients with IBS-C, and correlations were found between psychological distress and altered anorectal sensory thresholds, suggesting emotional factors may play a more influential role in IBS-C than in FC.

The study highlights that while clinical symptoms, manometry, and sensory thresholds can help characterize these subtypes of chronic constipation, they alone are insufficient to reliably distinguish IBS-C from FC. RSARM combined with specific dyssynergic patterns (type IV in FC and type III in IBS-C) may serve as useful indicators for identifying dyssynergic defecation, potentially guiding therapy. However, due to limitations in sample size and hospital-based recruitment, the findings may not be generalizable. Future research should include broader patient populations and investigate whether psychological and physiological profiles can more accurately inform tailored diagnostic and treatment strategies.

Reference: Lv CL, Song GQ, Liu J, et al. Colorectal motility patterns and psychiatric traits in functional constipation and constipation-predominant irritable bowel syndrome: A study from China. World J Gastroenterol. 2023 Nov 7;29(41):5657-5667. doi: 10.3748/wjg.v29.i41.5657. PMID: 38077156; PMCID: PMC10701329.