To assess the prevalence of constipation in individuals with amyotrophic lateral sclerosis (ALS) and examine its relationship to disease features in a retrospective cohort at a single institution.

Constipation is a common concern among individuals with ALS, though its true prevalence and association with disease characteristics remain unclear.

ALS participants completing a new intake form were evaluated at their most recent clinic visit for the presence of constipation, disease duration, percutaneous endoscopic gastrostomy (PEG) placement, forced vital capacity (FVC), use of BiPAP, total, bulbar domain, and gross motor domain scores on the revised ALS Functional Rating Scale (ALSFRS-R), and King’s staging. Group comparisons were conducted using unpaired Student’s t-test and Chi-square tests.

Constipation was reported by 59.5% (22/37) of participants. Those reporting constipation had significantly lower ALSFRS-R total scores (22.4 vs. 29.9, p=0.015), lower bulbar domain scores (5.9 vs. 9.0, p=0.004), and more advanced King’s staging (3.9 vs. 3.1, p=0.004) compared to those without constipation. Gross motor domain scores trended lower among those with constipation but did not reach statistical significance (3.9 vs. 6.1, p=0.083). Participants with constipation also had a significantly lower FVC (51.2% vs. 74.3%, p=0.006) and were more likely to use BiPAP (81.0% vs. 46.7%, p=0.032). No significant differences were observed for disease duration (28.5 vs. 24.7 months, p=0.744) or PEG placement (25% vs. 20%, p=0.737).

Constipation was reported in the majority of ALS participants. It correlated with lower total ALSFRS-R scores, higher King’s staging, lower FVC, and use of BiPAP, consistent with greater disease burden but not with disease duration. Constipation also correlated with lower ALSFRS-R bulbar but not gross motor domain scores, suggesting that poor oral intake represents a risk factor for constipation, whereas decreased mobility plays a less certain role. PEG placement did not appear to influence constipation, though few participants utilized enteral nutrition.