Trends in malignant mesothelioma incidence in Spain, 1999-2023: a joinpoint and age-period-cohort analysis

Malignant mesothelioma (MM) in Spain reflects historical asbestos consumption that peaked in the 1970s. Despite a 2002 ban, the absence of a national registry complicates burden estimation. We aimed to characterise incidence trends and generational risk patterns over 25 years.

This ecological study analysed Global Burden of Disease 2023 incidence data for Spain (1999-2023). Age-standardised incidence rates (ASIR) were calculated using the 2013 European Standard Population. Temporal trends were assessed via joinpoint regression. Age-period-cohort (A-P-C) modelling disentangled the independent effects of age, period, and birth cohort by sex.

In men, ASIRs increased from 1·55 to 1·94 per 100,000 (1999-2012), followed by a significant decline after 2016 (annual percentage change [APC] - 2·3%, 95% CI - 3·9- - 1·3; p < 0·001). In women, rates remained low and stable (0.45-0.50 per 100,000), with a modest increase over time (average annual percentage change 0.6%, p < 0.001). A-P-C modelling in men revealed a significant negative net drift (- 1·45% per year, p < 0·001) and strong birth cohort effects peaking in the 1944 cohort, with marked risk reduction in those born after 1964 (relative risk < 0·70). Women showed no significant cohort or period effects and minimal temporal variation.

Spain shows evidence of a meaningful epidemiological transition in its mesothelioma epidemic. The significant decline in male incidence since 2016 is consistent with the 2002 asbestos ban and the progressive ageing-out of heavily exposed cohorts.