LAUSR

OBJECTIVE To evaluate the association and dose-response pattern between antimalarial drugs and overall and cause specific mortality in SLE patients. METHODS Medical records including information on HCQ/chloroquine (CQ) prescription were extracted from Jiangsu Lupus database. The database was designed to collect data from SLE patients that first-hospitalized during 1999-2009 in Jiangsu province, China, and a follow-up for survival status was performed in 2010 and 2015. Cox and restricted cubic spline models were used to estimate the hazard ratio and 95% CI. RESULTS We identified 221 deaths among 2446 SLE patients in total. Compared with non-users, decreased overall mortality was associated with either HCQ or CQ users, with adjusted hazard ratio (95% CI) of 0.49 (0.35, 0.67) and 0.49 (0.27, 0.87), respectively. The association between HCQ/CQ and overall mortality was similar across subgroups, such as patients with comorbidities and organ involvements. Interestingly, both the time and the daily dosage of HCQ/CQ use were related to decreased mortality of SLE in a linear dose-response relationship. In cause specific analyses, HCQ/CQ was inversely associated with death from renal insufficiency and other organ (cardiopulmonary, gastrointestinal and haematological) involvements, with adjusted hazard ratio (95% CI) of 0.23 (0.09, 0.55) and 0.25 (0.10, 0.62), respectively, yet it was not significantly associated with mortality from infection and neuropsychiatric involvements. CONCLUSION Antimalarial drugs were associated with lower risk of SLE mortality, especially renal insufficiency- and other organ involvement-related death. The protective effects for survival might be augmented by adherence and full dosage of these drugs.