Patterns of Comorbidity and Multimorbidity among Patients with Multiple SclerosisinaLargeUSCommerciallyInsuredandMedicareAdvantagePopulation

Abstract

Background: Comorbidities are common in patients with multiple sclerosis (MS), thus increasing the complexity of disease management and economic burden and worsening their prognosis and quality of life. Real-world evidence comparing comorbidities and multimorbidity patterns of commercially insured vs Medicare enrollees with MS is lacking. Objective: To evaluate the patterns of comorbidity and multimorbidity among patients with MS in a US commercially insured and Medicare Advantage population. Methods: This retrospective observational cohort study was conducted using Aetna health claims data from January 1, 2015, to October 31, 2019. Eligibility criteria were (1) at least 3 MS-related inpatient/outpatient (ICD-10-CM: G35), or disease-modifying therapy claims within 1 year (date of first claim = index date); (2) Aetna commercial health plan or Medicare Advantage medical and pharmacy benefits at least 12 months pre-/post-index; and (3) age 18 and older. Commercially insured patients, Medicare Advantage patients younger than 65 years of age, and Medicare Advantage patients 65 years and older were compared. Results: Among 5000 patients (mean [SD] age, 52.6 [12.9]; 75.2% female), 53% had commercial insurance and 47% had Medicare Advantage (59.2% disabled age <65). Medicare Advantage patients were older (age <65: 53.3 [7.9]; age ≥65: 70.8 [5.2]) vs commercial (age, 45.7 [10.2]), had greater comorbidity burden (Charlson Comorbidity Index; age <65: 1.17 [1.64], age ≥65: 1.65 [1.95]) vs commercial (0.53 [1.02]) (all P