Objective: In patients with systemic lupus erythematosus (SLE), hydroxychloroquine prevents disease flares and damage accrual and facilitates the response to mycophenolate mofetil in those with renal involvement. We have now examined if hydroxychloroquine also exerts a protective effect on survival.
Methods: SLE patients from the multiethnic LUMINA (Lupus in Minorities: Nature vs nurture) cohort were studied. A case-control study within the context of this cohort in which deceased patients (cases) matched for disease duration (within six months) with alive patients (controls) in a 3 to 1 proportion was performed. Survival was the outcome of interest. Propensity scores were derived by logistic regression to adjust for confounding by indication as lupus patients with milder disease manifestations are more likely to be prescribed hydroxychloroquine. A conditional logistic regression model was used to estimate the risk of death and hydroxychloroquine use with and without the propensity score as the adjustment variable.
Results: There were 608 patients. Of them 61 patients had died (cases). Hydroxychloroquine had a protective effect on survival. The odds ratio (OR) and 95% Confidence Interval (CI) were 0.128 and 0.054-0.301 for hydroxychloroquine alone and OR= 0.319, 95% CI 0.118- 0.864 after adding the propensity score. As expected, the propensity score itself was also protective.
Conclusions: Hydroxychloroquine, which overall is well tolerated by patients with SLE, has a protective effect on survival which is evident even after taking into consideration the factors associated with treatment decisions. This information is of importance to all clinicians involved in the care of lupus patients.
- propensity Score