Systemic lupus erythematosus in the elderly: antimalarials in disease remission

Antimalarials in Lupus Nephritis: How Strong Is the Evidence?

SLE is a chronic multisystem autoimmune disease that affects the kidneys in approximately 50% of patients, with the prevalence rising to as high as 70% in certain populations, such as African American and Asian people. Antimalarials-and particularly hydroxychloroquine (HCQ)-are currently considered a mainstay of therapy, together with immunosuppressants. Over the past decades, several studies have extensively investigated the mechanisms of action of antimalarial agents and their potential beneficial properties in patients with SLE in general. However, the evidence for the therapeutic benefit of HCQ in patients with lupus nephritis (LN) derives mainly from observational studies, conducted in an era before the refinement of induction and maintenance protocols for immunosuppressive therapy. Despite the paucity of high-quality evidence on its efficacy in LN, the nephrology community widely supports the universal use of HCQ in patients with LN, and recommendations for its use are firmly entrenched in various clinical practice guidelines. Nonetheless, the use of antimalarials may also carry inherent risks, underscoring the importance of personalized approaches in these patients. Herein, we comprehensively review the available literature on antimalarials in LN, aiming to update the current evidence, limitations, and future perspectives for the use of antimalarials in adults.

Hydroxychloroquine in systemic lupus erythematosus: overview of current knowledge

The antimalarial hydroxychloroquine (HCQ) has demonstrated several crucial properties for the treatment of systemic lupus erythematosus (SLE). Herein, we reviewed the main HCQ pharmacologic features, detailed its mechanism of action, and summarized the existing guidelines and recommendations for HCQ use in rheumatology with a systematic literature search for the randomized controlled trials focused on lupus. HCQ has been shown to decrease SLE activity, especially in mild and moderate disease, to prevent disease flare and to lower the long-term glucocorticoid need. The numerous benefits of HCQ are extended to pregnancy and breastfeeding period. Based on cohort studies, antithrombotic and metabolic HCQ’s effects were shown, including lipid-lowering properties, which might contribute to an improved cardiovascular risk. Moreover, early HCQ use in antinuclear antibodies positive individuals might delay the progression to SLE. Finally, HCQ has a significant favorable impact on long-term outcomes such as damage accrual and mortality in SLE. Based on these multiple benefits, HCQ is now the mainstay long-term treatment in SLE, recommended by current guidelines in all patients unless contraindications or side effects. The daily dose associated with the best compromise between efficacy and safety is matter of debate. The concern regarding retinal toxicity rather than proper efficacy data is the one that dictated the daily dosage of ⩽5 mg/kg/day actual body weight currently agreed upon.

The early protective effect of hydroxychloroquine on the risk of cumulative damage in patients with systemic lupus erythematosus

OBJECTIVE

To assess whether hydroxychloroquine (HCQ) prevents early damage in patients with systemic lupus erythematosus (SLE).

METHODS

We updated an existing systematic review of literature on clinical effects of HCQ in patients with SLE. We conducted a nested case-control study embedded in an inception cohort of patients with SLE. Systemic Lupus International Collaborating Clinics Damage Index (SDI) at 3 years was considered as our primary outcome. Patients with SDI > 0 at 3 years were considered cases and patients with SDI = 0 were controls. Cases and controls were first compared by univariate analysis. Then conditional logistic regression models adjusting for potential confounders were done to study the effect of HCQ on damage accrual.

RESULTS

Included in the analysis were 481 patients who had 3 or more years of followup. Out of this cohort, we could match 151 cases with 151 controls. Univariate analysis identified age, the use of any immunosuppressive drugs, HCQ, and cumulative dose of steroids as significant covariates associated with damage accrual. In multivariate analysis, the use of HCQ remained significantly associated with less damage (OR 0.34, 95% CI 0.132-0.867), while age (OR 1.05, 95% CI 1.027-1.078) and a variable combining SLE activity and steroid dose (OR 1.73, 95% CI 1.306-2.295) were associated with damage at 3 years.

CONCLUSION

We demonstrated that HCQ use was associated with less damage at 3 years after diagnosis of SLE when attention was given and adjustment done for disease activity and steroid dose, duration of disease, and calendar year of diagnosis.

[Systemic lupus erythematosus in the elderly]

Late-onset systemic lupus erythematosus (SLE) usually appears in patients older than 65 years and has clinical features different from the classical form observed in younger patients. In the elderly, SLE represents 10-20% of all SLE cases, shows a different and less aggressive clinical evolution and the first manifestations are non-specific. A significantly higher incidence of late-onset SLE in males, and the fact that postmenopausal women have a more benign disease, suggests that the estrogenic status may influence the activity of the disease. Owing to the insidious onset and the non-specific clinical manifestations on presentation, there is commonly a delayed diagnosis of late-onset SLE. Furthermore, the presence of comorbidities and concomitant therapies in elderly patients may limit the therapeutic options for SLE. The treatment of choice of joint symptoms and serositis includes non-steroidal anti-inflammatory drugs and low-dose steroids for short periods. In addition to the need for adopting a multidisciplinary approach, it is fundamental to obtain information about the functional, cognitive and social status of these patients in order to make appropriate healthcare decisions.

The role of antimalarial agents in the treatment of SLE and lupus nephritis

Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease that affects various organs. Lupus nephritis is one of the most common, and most important, serious manifestations of SLE. Antimalarial agents are part of the immunomodulatory regimen used to treat patients with SLE; however, their role in the treatment of patients with lupus nephritis in particular is less well recognized, especially by nephrologists. Not all antimalarial agents have been used in the treatment of lupus; this Review will focus on studies using chloroquine and hydroxychloroquine. In addition, this Review will briefly describe the history of antimalarial drug use in patients with SLE, the theorized mechanisms of action of the agents chloroquine and hydroxychloroquine, their efficacy in patients with SLE and those with lupus nephritis, their use in pregnancy, and potential adverse effects. The Review will also cover the latest recommendations regarding monitoring for hydroxychloroquine-associated or chloroquine-associated retinopathy. Overall, antimalarial drugs have numerous beneficial effects in patients with SLE and lupus nephritis, and have a good safety profile.

Developments in the clinical understanding of lupus

Advances in genetics and new understanding of the molecular pathways that mediate innate and adaptive immune system activation, along with renewed focus on the role of the complement system as a mediator of inflammation, have stimulated elaboration of a scheme that might explain key mechanisms in the pathogenesis of systemic lupus erythematosus. Clinical observations identifying important comorbidities in patients with lupus have been a recent focus of research linking immune mechanisms with clinical manifestations of disease. While these advances have identified rational and promising targets for therapy, so far the therapeutic trials of new biologic agents have not met their potential. Nonetheless, progress in understanding the underlying immunopathogenesis of lupus and its impact on clinical disease has accelerated the pace of clinical research to improve the outcomes of patients with systemic lupus erythematosus.