A lupus cohort study from British Columbia, Canada has shown that medication adherence with hydroxychloroquine (HCQ) is associated with a 71% to 83% lower mortality.
Researchers identified all incident SLE cases taking antimalarials (AM) from provincial administrative databases between 1997 adn 2015 to examine all‐cause mortality and its relationship with medication adherence. Adherence was measured as the proportion of days covered (PDC), with those adherent having a PDC≥0.90, and the non‐adherent having a PDC<0.90), compared with those who discontinued (PDC=0) during a 30‐day window.
We identified 3,062 incident SLE patients on antimalarials (mean age 46.9 years). Death was observed in 242 (7.9%) after a mean follow‐up of 6.4 years.
Compared with those who discontinued therapy, mortality was lower for AM adherent (adjusted hazard ratio [aHR] 0.20; 95% CI:0.13‐0.29) and non‐adherent SLE patients (aHR 0.62; 95% CI:0.42‐0.91). A significant trend in the aHRs of mortality risk over the adherence levels was found (p‐value:<0.001).
Chronic adherence to antimalarial therapy in SLE resulted in a 71% and 83% lower risk of death. This critically important, given the data showing that 40-50% of SLE patients are noncompliant with hydroxychloroquine.