Mortality in patients with psoriatic arthritis in Sweden: a nationwide, population-based cohort study

• Published in: Annals of the rheumatic diseases Vol. 83; no. 4; pp. 446 - 456
• Main Authors: Exarchou, Sofia, Di Giuseppe, Daniela, Klingberg, Eva, Sigurdardottir, Valgerdur, Wedrén, Sara, Lindström, Ulf, Turesson, Carl, Jacobsson, Lennart T H, Askling, Johan, Wallman, Johan K
• Format: Journal Article
• Language: English
• Published: England BMJ Publishing Group Ltd and European League Against Rheumatism 01.04.2024; Elsevier Limited
• Subjects: Adult; Arthritis; Arthritis, Psoriatic; Arthritis, Psoriatic - epidemiology; Autoimmunitet och inflammation; Autoimmunity and Inflammation; Cardiovascular disease; Cardiovascular diseases; Cardiovascular Diseases - epidemiology; Cause of Death; Codes; Cohort analysis; Cohort Studies; Comorbidity; Death; Diagnosis; Emigration; Epidemiology; Female; Humans; Incidence; Inflammatory diseases; Internal medicine; Malignancy; Mortality; Patients; Population studies; Population-based studies; Prescription drugs; Psoriasis; Psoriatic; Psoriatic arthritis; Rheumatoid arthritis; Rheumatology; Sex; Sweden; Sweden - epidemiology; Sweden; Sweden; Arthritis, Psoriatic; Epidemiology; Mortality; Cause of Death
• ISSN: 0003-4967; 1468-2060; 1468-2060
• DOI: 10.1136/ard-2023-224965

ObjectivesTo compare all-cause mortality and causes of death between patients with psoriatic arthritis (PsA) and the general population in Sweden.MethodsAdults with at least one main PsA diagnosis (International Classification of Diseases-10: L40.5/M07.0–M07.3) from outpatient rheumatology/internal medicine departments 2001–2017 were identified from the National Patient Register. Each case was matched to five population comparator-subjects on sex/county/age at the case’s first arthritis diagnosis. Follow-up ran from 1 January 2007, or from first PsA diagnosis thereafter, until death, emigration or 31 December 2018. Mortality was assessed overall, and stratified by sex and duration since diagnosis (diagnosis before/after 1 January 2007), using matched Cox proportional hazard regression (excluding/including adjustments for comorbidity) or Breslow test, as appropriate. Incidence rate ratios (IRR) of death, overall and stratified by sex/duration since diagnosis/age, as well as causes of death in PsA cases and comparator-subjects were also described.ResultsAll-cause mortality was elevated in PsA (HR: 1.11 (95% CI: 1.07 to 1.16); IRR: 1.18 (95% CI: 1.13 to 1.22)), mainly driven by increased risks in women (HR: 1.23 (95% CI: 1.16 to 1.30)) and cases with longer time since diagnosis (HR: 1.18 (95% CI: 1.12 to 1.25)). IRR of death were significantly increased for all ages except below 40 years, with the numerically highest point-estimates for ages 40–59 years. When adjusted for comorbidity, however, the elevated mortality risk in PsA disappeared. Causes of death were similar among PsA cases/comparator-subjects, with cardiovascular disease and malignancy as the leading causes.ConclusionsMortality risk in PsA in Sweden was about 10% higher than in the general population, driven by excess comorbidity and with increased risks mainly in women and patients with longer disease duration.