Slow Colonic Transit in Systemic Sclerosis: An Objective Assessment of Risk Factors and Clinical Phenotype

Objective: Up to 50% of patients with systemic sclerosis (SSc) experience slow colonic transit, which may be associated with severe outcomes. Our objective, therefore, was to identify specific clinical features associated with slow colonic transit in SSc. Methods: SSc patients with gastrointestinal symptoms were prospectively enrolled and completed a scintigraphy-based whole gut transit study. Clinical features were compared between patients with and without slow colonic transit in univariate and multivariable logistic regression analyses. Results: Forty-eight of 100 patients (48%) in our cohort had slow colonic transit. In the univariate analyses, slow colonic transit was positively associated with female sex (odds ratio [OR] 12.61 [95% confidence interval (95% CI) 1.56–101.90]), telangiectasia (OR 4.00 [95% CI 1.32–12.10]), anticentromere antibodies (OR 3.25 [95% CI 1.25–8.44]), prior or current smoking (OR 2.56 [95% CI 1.06–6.21]), and a Medsger gastrointestinal severity score of ≥3 (OR 3.94 [95% CI 1.16–13.36]). Patients were less likely to have significant restriction on pulmonary function tests (OR 0.23 [95% CI 0.09–0.63]). In our multivariable model, the association between slow colonic transit and telangiectasia (OR 3.97 [95% CI 1.20–13.20]) and less restrictive lung disease on pulmonary function tests (OR 0.28 [95% CI 0.09–0.86]) remained statistically significant, though a trend with smoking remained (OR 2.16 [95% CI 0.82–5.75]). Interestingly, there were no significant associations between slow colonic transit and delayed transit in other regions of the gastrointestinal tract. Conclusion: Distinct clinical features are associated with slow colonic transit in SSc. Such features may provide insight in risk stratification and the study of disease mechanism in more homogeneous subgroups.