Delayed gastric emptying determined using the 13C-octanoic acid breath test in patients with systemic sclerosis

To determine the prevalence of delayed gastric emptying using the 13C-octanoic acid breath test in unselected patients with systemic sclerosis (SSc), to evaluate whether findings of the 13C-octanoic acid breath test are associated with clinical digestive manifestations, gastric mucosal abnormalities detected by gastroscopy, motor activity dysfunction detected by antroduodenal manometry, and esophageal motor impairment and extradigestive manifestations of SSc, and to develop a risk prediction score of gastric emptying in SSc.

Consecutive patients with SSc (n=57) underwent the 13C-octanoic acid breath test. All of the patients with SSc completed a questionnaire on digestive symptoms, and a global symptom score (GSS) was calculated.

The prevalence of delayed gastric emptying was 47.4% in patients with SSc. A marked correlation was observed between a GSS of digestive symptoms≥5 and the presence of delayed gastric emptying (P<0.00001). The sensitivity of a GSS≥5 for predicting delayed gastric emptying was as high as 0.93, while the specificity was 0.73. Moreover, a GSS≥5, mucosal gastric abnormalities, severe esophageal motor impairment, and interstitial lung disease were factors that were independently associated with the presence of delayed gastric emptying, and these variables were used to create a risk prediction score. The area under the receiver operating characteristic curve for the risk prediction score was 0.90; the sensitivity of this score for the prediction of delayed gastric emptying was 0.93, while the specificity was 0.77.

The results indicate that delayed gastric emptying occurs often in patients with SSc. Interestingly, using risk models with routine clinical characteristics, a simple risk prediction score can be calculated, allowing prediction of the occurrence of delayed gastric emptying in patients with SSc.