Longitudinal Treatment Patterns and Associated Outcomes in Patients With Newly Diagnosed Systemic Lupus Erythematosus

• Published in: Clinical therapeutics 2016-03, Vol.38 (3), p.610-624
• Main Authors: Kan, Hong, PhD, Nagar, Saurabh, Patel, Jeetvan, PhD, Wallace, Daniel J., MD, Molta, Charles, MD, Chang, David J., MD, MPH
• Format: Article
• Language: English
• Subjects: Adolescent; Adrenal Cortex Hormones - administration & dosage; Adrenal Cortex Hormones - therapeutic use; Adult; clinical outcomes; cluster analysis; Databases, Factual; economic outcomes; Female; Humans; Hydroxychloroquine - administration & dosage; Immunosuppressive Agents - administration & dosage; Immunosuppressive Agents - therapeutic use; Internal Medicine; Longitudinal Studies; Lupus Erythematosus, Systemic - drug therapy; Male; Managed Care Programs; Medical Education; Methotrexate - therapeutic use; Middle Aged; Mycophenolic Acid - analogs & derivatives; Mycophenolic Acid - therapeutic use; Retrospective Studies; systemic lupus erythematosus; treatment patterns; Young Adult
• ISSN: 0149-2918; 1879-114X
• DOI: 10.1016/j.clinthera.2016.01.016

Abstract Purpose The treatment of systemic lupus erythematosus (SLE) is complex, with a wide range of drugs commonly prescribed. The aims of this study were to identify longitudinal treatment patterns in patients with incident SLE and to estimate the associations of treatment patterns with clinical and economic outcomes. Methods This retrospective, observational cohort study used a US managed care claims database to identify patients with newly diagnosed SLE and 4-year treatment follow-up. Patients were aged ≥18 years, with continuous medical and pharmacy benefits for 12 months before and 48 months after the index date (first medical claim with a diagnosis of SLE). Longitudinal treatment patterns were grouped using a k-means cluster analysis. Therapies were included in the cluster analysis if the mean number of prescriptions in each year was ≥0.05. Clinical and economic outcomes were compared across clusters using multivariate regression analyses. Findings Data from 1611 patients with incident SLE were analyzed (91.4% women; mean [SD] age, 44.5 [9.5] years; 56.2% managed primarily by a specialist). Hydroxychloroquine and corticosteroids were the most commonly prescribed therapies; methotrexate, azathioprine, and mycophenolate mofetil also met the criteria for inclusion in the cluster analysis. Ten treatment clusters were identified; the most common was minimally treated patients (42.8%). Hydroxychloroquine monotherapy, corticosteroid monotherapy, and corticosteroid/hydroxychloroquine combination therapy were received by 34.0%, 11.2%, and 7.8% of patients, respectively. Methotrexate or azathioprine with a corticosteroid/hydroxychloroquine were received by 4.2% of patients. Changes in therapy, except discontinuations, were rare. Compared with the minimally treated cluster, those that received corticosteroid monotherapy (mean dose, >12.0 mg/d) had poorer clinical and economic outcomes; the hydroxychloroquine-monotherapy cluster had similar or better outcomes; and patients who received a corticosteroid/hydroxychloroquine with or without methotrexate or azathioprine demonstrated outcomes that were poorer but that appeared better than those with corticosteroid monotherapy. SLE-related visits with a nonspecialist were common (~45%) and remained unchanged over time despite better clinical and economic outcomes associated with specialist visits. Implications This study utilized cluster analysis, an unsupervised machine-learning method, to systematically discern tre