Mortality and cardiovascular morbidity among patients diagnosed with Takayasu's arteritis: a Danish nationwide cohort study

OBJECTIVES: To assess the long-term mortality and risk of cardiovascular events (CVE) among Danish patients with Takayasu's arteritis (TAK).

METHODS: Administrative registers with nationwide coverage were used to identify patients diagnosed with TAK in Denmark during 1994-2014 and construct an age- and gender-matched cohort of population-controls. CVE were identified by means of hospital discharge diagnoses and categorised as major or minor, based on severity. Cox regression analyses were used to calculate hazard ratios (HRs) for death and first-time hospitalisations for CVE as a measure of relative risk.

RESULTS: 79 patients with TAK were identified, corresponding to an incidence rate of 0.7 (95% confidence interval (CI): 0.6-0.9)/million/year. Median duration of follow-up in the TAK cohort was 6.4 (IQR: 3.7-11) years. Mortality was significantly higher among the TAK patients than among the population controls during the first 3 years of follow-up [HR for death: 8.0 (95% CI: 3.0-21)], but not after >3 years [HR for death: 0.5 (95% CI: 0.1-3.5)]. Risk of CVE was significantly increased among TAK patients after ≤3 years [HR for major CVE: 12 (95% CI: 3.8-37), HR for minor CVE: 19 (95% CI: 7.5-50)] as well as after >3 years [HR for major CVE: 7.6 (95% CI: 2.8-21), HR for minor CVE: 3.0 (95% CI: 1.01-9.0)].

CONCLUSIONS: Compared to the general population, patients with TAK experience markedly increased mortality during early follow-up periods. The long-term risk of CVE is high among patients affected by the disease.