Hydroxychloroquine was associated with reduced risk of new-onset diabetes mellitus in patients with Sjogren syndrome

Objectives: To determine whether taking hydroxychloroquine (HCQ) could prevent the development of new-onset diabetes mellitus (DM) among patients with Sjogren syndrome (SS). Methods: This is a nationwide, population-based, retrospective cohort study utilizing the Taiwan National Health Insurance Research Database (NHIRD). Data were collected from 1 January 1999, through 31 December 2013, using the International Classification of Diseases, Ninth Revision, Clinical Modification codes. In total, 7774 patients newly diagnosed with SS by at least three outpatient visits or one inpatient admission were selected from the NHIRD as participants. Patients who had previously been diagnosed with DM and whose follow-up durations shorter than 90 days were excluded. HCQ exposure group includes patients who had been diagnosed with SS no longer than 180 days previously, and had been prescribed HCQ for the first time for at least 90 days. The diagnosis of DM was defined as at least two outpatient visits or one inpatient admission with anti-diabetic medication prescription. Results: Patients with SS treated with HCQ had a significantly lower cumulative incidence of new-onset DM than those not treated with HCQ (adjusted hazard ratio: 0.51, 95% confidence interval: 0.28-0.96, P < 0.05). HCQ use for 3 years or more had favorable protective effects (adjusted hazard ratio: 0.22, CI: 0.05-0.92). Conclusions: HCQ reduced the incidence of DM in a time and dose-dependent manner. Patients with SS who had taken HCQ for 3 years or more exhibited significant protective effects against developing new-onset DM.