Long-term hydroxychloroquine treatment improves survival in lupus patients
Patients with systemic lupus erythematosus (SLE) on hydroxychloroquine (HCQ) fare better, having lower mortality rates compared with those not using the drug, a study has shown. This survival benefit is further enhanced by treatment adherence.
The study included 2,287 SLE patients treated with HCQ (mean age at diagnosis 35.7 years; 88.4 percent female) and 2,287 propensity-score matched non-HCQ controls from the Taiwan National Health Insurance Research Database (NHIRD). Of these, 169 and 248 died, respectively, during a mean follow-up of 7.6 years.
Specifically, HCQ reduced the risk of death by about 30 percent (hazard ratio [HR], 0.68; 95 percent CI, 0.56–0.82). This survival benefit improved with increased adherence to treatment, such that relative to nonusers, patients with HCQ medication possession ratio (MPR) of ≥80 percent showed the lowest mortality risk (HR, 0.60), followed by those with 40 percent ≤ MPR <80 percent (HR, 0.72) or MPR <40 percent (HR, 0.79). [Rheumatology 2018;doi:10.1093/rheumatology/key167]
With respect to secondary outcomes, HCQ use likewise led to significantly better results. Compared to nonuse, annual prednisolone-equivalent glucocorticoid dose was lower (regression coefficient, –0.22; p=0.008), annual admissions due to SLE were fewer (rate ratio [RR], 0.90; p<0.001), and annual number of emergency room visits was smaller (RR, 0.94; p=0.006).
HCQ has been shown to reduce SLE activity, and treatment maintenance could protect patients with quiescent SLE against a clinical flare-up. According to the authors, the findings imply that the survival improvement may have resulted from decreased disease activity in patients treated with HCQ.
“To our knowledge, only a few studies have examined the association between survival and HCQ among patients with SLE, and this is the only one in Asia,” they said.
However, the study was not able to directly assess SLE activity using a common index such as the SLEDAI (Systemic Lupus Erythematosus Disease Activity Index) or the BILAG (British Isles Lupus Assessment Group) criteria, as linking the NHIRD to individual laboratory results of patients was forbidden for privacy reasons.
Nevertheless, the authors recommended persistent use of HCQ for all SLE patients, owing to the benefits of the drug. Treatment adherence should be actively improved via interventions such as providing education to raise awareness and organizing care with a nurse manager.