RESUMEN
Introduction: Gastrointestinal tract involvement in systemic sclerosis is the most common internal organ involvement. Among the few validated patient-reported outcome measures for gastrointestinal involvement are the University of California Los Angeles Scleroderma Clinical Trial Consortium gastrointestinal tract 2.0 (UCLA-GIT 2.0) and the gastrointestinal problems' visual analog scale (SHAQ-VAS). The latter is a component of the Scleroderma Health Assessment Questionnaire Disability Index. Our aim is to compare the responsiveness of the UCLA-GIT 2.0 total score, single domains, upper and lower gastrointestinal domains, and gastrointestinal problems' visual analog scale of the scleroderma HAQ(SHAQ-GI-VAS) to change in gastrointestinal medication. In addition, we evaluated the correlation between the UCLA-GIT 2.0 and SHAQ-GI-VAS scale in our systemic sclerosis population. Methods: One hundred fifteen systemic sclerosis patients attending the University of California Los Angeles and Seattle outpatient clinics with two or more consecutive visits were enrolled in our study. The UCLA-GIT 2.0 and SHAQ_VAS were completed by all patients at both visits; any change in gastrointestinal medication at the baseline visit was reported. UCLA-GIT 2.0 asks about how the gastrointestinal tract affects the patient over the last week; It consists of 34 questions in seven domains (reflux, distension, soilage, diarrhea, social function, emotional wellbeing, and constipation). THE SHAQ-GI-VAS is a 100-mm horizontal VAS that asks the patient; "In the past week, how much did your gastrointestinal symptoms interfere with your function". These measures were evaluated at two consecutive visits. Any change in gastrointestinal medication at baseline visit was reported. Percent change was calculated to evaluate the change in the values of the UCLA-GIT 2.0 and the SHAQ_GI-VAS, and we dichotomized the patients into two groups according to whether there was a change in gastrointestinal treatment or not. Pearson correlation was used to correlate both tests at baseline. Results: Ninety-eight (85%) of the systemic sclerosis patients were females, mean age: 52 years (standard deviation ± 12.9); median disease duration: 7 (range: 4-11 years), diffuse subtype: 57 patients (50%), median baseline gastrointestinal tract 2.0 was 0.3 (0.1-0.7) and median baseline SHAQ-GI-VAS was 0.8 (0-4.1). Out of the 115 patients, 41 (37.0%) patients needed a change in gastrointestinal medication at baseline visit (Group 1); they were compared to those not changing gastrointestinal medications (Group 2). Responsiveness to gastrointestinal medication treatment change in the form of percent change in total UCLA-GIT 2.0 was significantly more in Group 1 than in Group 2 (-6.6 (standard deviation = 20) in Group 1 vs +6.9 (standard deviation ± 18.8) in Group 2, p value < 0.001). On the contrary, there was no statistically significant difference between percent changes in SHAQ-GI-VAS from the in Group 1 versus Group 2 (59.5 (standard deviation ± 172) in Group 1 vs 51.9 (standard deviation ± 126.4) in Group 2, p value = 0.816). The correlation between the UCLA-GIT 2.0 and the SHAQ_GI-VAS was moderate (r = 0.6). Conclusion: The University of California Los Angeles Scleroderma Clinical Trial Consortium gastrointestinal tract 2.0 and gastrointestinal problems' visual analog scale are utilized to measure gastrointestinal tract involvement in systemic sclerosis. Unlike the gastrointestinal problems' visual analog scale, the gastrointestinal tract 2.0 was responsive to change in gastrointestinal medication while the SHAQ-GI-VAS was not. Hence, the UCLA-GIT 2.0 could be utilized in future trials and observational studies as a measure of systemic sclerosis gastrointestinal responsiveness.