Direct and indirect costs of systemic sclerosis and associated interstitial lung disease: A nationwide population‐based cohort study

BACKGROUND AND OBJECTIVE: The study aimed to evaluate the direct and indirect costs of systemic sclerosis (SSc) in cases with and without interstitial lung disease (ILD). METHODS: Cases diagnosed with SSc (2002–2015) were identified in the Danish National Patient Registry. Cases were matched 1:4 with non‐SSc controls from the general population. Data on costs were obtained from national databases. Excess cost was estimated as the annual cost per case subtracting the costs of the control. RESULTS: We identified 1869 cases and 7463 controls. Total excess cost (direct healthcare, elderly care and indirect costs) in the SSc‐ILD cohort was €29,725, and €17,905 in the non‐ILD SSc cohort. In‐ and out‐patient contacts and forgone earnings were the key drivers of costs in both cohorts. Healthcare costs were higher before and after the diagnosis compared with the controls. Men incurred higher excess healthcare costs than women. Hospitalization and outpatient services were the key drivers of the gender‐associated differences. Income from employment decreased more rapidly after diagnosis in the SSc‐ILD cohort than in the non‐ILD SSc cohort. Public transfer income increased after diagnosis, with the most pronounced difference in the SSc‐ILD cohort. Disability pension was the key driver of public transfer income. CONCLUSION: SSc is associated with a significant individual and societal burden that is evident several years before and after the diagnosis. Total excess costs are higher in SSc‐ILD than in the non‐ILD SSc underlining the severity of pulmonary involvement. Initiatives to maintain work ability and to reduce hospital admissions may reduce the economic burden of SSc.