Suicidal and accidental drug poisoning mortality among older adults and working-age individuals in Spain between 2000 and 2018.

BACKGROUND: Although medication poisoning in older adults is considered an increasingly important, but preventable cause of death, it has received relatively little attention. We explored recent trends and correlates of suicidal and accidental fatal drug poisonings among older and working-age individuals using nationwide data from Spain.

METHODS: We identified all 15,353 fatal drug poisonings involving decedents aged ≥15 years in Spain between 2000 and 2018 and divided them by age into older adults (≥65 years) and working-age (15-64 years) individuals. For each age group, we analyzed time trends in suicidal and accidental fatal drug poisoning rates (overall and by ICD-10 drug categories) using joinpoint regressions. To understand the specific drugs classified as "Non-psychotropic/non-specified", we used 2018 data including substance-specific ICD-10 supplementary codes. We explored relevant sociodemographic correlates of suicidal and accidental fatal poisoning rates using multivariable negative binomial regressions.

RESULTS: Between 2000 and 2018, suicidal fatal poisonings increased faster among older (from 0.19 to 0.63 per 100,000 - average annual change: 7.7%) than working-age individuals (from 0.40 to 0.72 per 100,000 - average annual change: 3.8%). Accidental fatal poisonings increased among older adults (from 0.25 to 2.67 per 100,000 - average annual change: 16.2%) but decreased among working-age counterparts (from 2.38 to 1.42 per 100,000 - average annual change: - 1.9%). Anticoagulants and cardiac-stimulants glycosides accounted for 70% of the 223 accidental fatal poisonings due to non-psychotropic/non-specified drugs registered among older adults in 2018. Roles of gender and urban dwelling in suicidal and accidental poisonings were heterogeneous across age groups.

CONCLUSION: Increases in suicidal drug poisonings were faster among older than working-age individuals. Accidental fatal poisonings increased only among older adults. Our findings that (i) sociodemographic correlates were heterogeneous across age groups and (ii) anticoagulant and cardiac-stimulant glycosides were particularly salient drivers of accidental poisonings among older adults have implications for prevention.