Systemic sclerosis mortality trends in Spain from 1980 to 2019: age‐period‐cohort and Joinpoint analysis

Abstract

Background: Systemic sclerosis (SSc) is an autoimmune chronic rheumatic disease with a high mortality rate, which continues to be a challenge for clinicians today.

Aim: To assess changes in mortality trends in the Spanish SSc population between 1980 and 2019, taking into account the independent effects of sex, age, time period and birth cohort.

Methods: SSc death records and mid-year population data were collected from the National Statistics Institute. Age-standardized mortality rates were calculated for the overall population and for each sex (male, female) and age group (5-year groups). Significant changes in mortality trends were identified by joinpoint regressions. An age-period-cohort (APC) analysis and potential years of life lost (PYLL) analysis were performed to identify the burden of SSc.

Results: Age-standardized mortality rates due to SSc increased from 1.87 (95% CI 1.00-3.02) per 1 000 000 inhabitants between 1980 and 1984, to 2.47 (95% CI 1.74-3.02) per 1 000 000 inhabitants between 2015 and 2019. The relative risk of mortality fell in all groups in cohorts born after 1990. The PYLL rates showed a gradual rise for both sexes.

Conclusion: There was an increase in overall SSc mortality in Spain during the 39 years evaluated, although there was a progressive drop for men.