Changing trends in drug overdose mortality in Spain, 2001-2022.

Abstract

Aim: To measure the evolution of drug overdose mortality in Spain between 2001 and 2022.

Design, setting, participants: A repeated cross-sectional observational study using nationwide mortality data from Spain, 2001-2022, among individuals aged 15-64 years.

Measurements: The outcome was overdose deaths [International Classification of Diseases, 10th revision (ICD-10) codes: X40-X44, X60-X64, X85, Y10-Y14]. Annual age-standardized mortality rates (ASMRs) per million person-years were estimated. Joinpoint regression assessed changes in trends using annual percentage change (APC) and average APC (AAPC). Overdose deaths were grouped by the underlying drug categories involved: nonopioid analgesics, antipyretics and antirheumatics (X40/X60/Y10); antiepileptic, sedative-hypnotic, antiparkinsonism and psychotropic drugs (X41/X61/Y11); narcotics and psychodysleptics (X42/X62/Y12); other drugs acting on the autonomic nervous system (X43/X63/Y13); other and unspecified drugs, medicaments and biological substances (X44/X64/Y14); and drugs, medicaments and biological substances in the context of assault (X85). Intentionality (based on ICD-10 code characters) within the underlying drug categories was assessed. All analyses were stratified by sex.

Findings: In Spain, 15 862 overdose deaths occurred during 2001-2022. ASMR increased by 49.0% over the period, from 24.7 [95% confidence interval (95% CI) = 23.0, 26.5] to 36.8 (95% CI = 34.7, 39.0) deaths per million person-years. APC showed a statistically significant change in trends in 2010, shifting from a -3.3% (95% CI = -7.3 to -1.7) decline to an increase of 3.4% (95% CI = -0.3 to 6.5). In 2018, a more abrupt change was observed, with the APC further increasing to 13.8% (95% CI = 9.3, 22.5). Females showed an earlier trend change (2006) with an AAPC 1.7 times higher (3.4%; 95% CI = 2.4, 4.7) than males (2.0%; 95% CI = 1.2, 2.7). Leading drug categories were other and unspecified drugs, medicaments and biological substances, followed by narcotics and psychodysleptics. In males, trends followed the overall pattern; in females, the antiepileptic, sedative-hypnotic, antiparkinsonism and psychotropic drugs category predominated, mostly due to intentional overdoses.

Conclusions: Between 2001 and 2022, drug overdose deaths in Spain increased substantially, beginning in 2010 and further accelerated in 2018, though population rates remain low. The most prevalent underlying ICD-10 drug categories were other and unspecified drugs, medicaments and biological substances-likely reflecting polydrug use-and narcotics and psychodysleptics. The observed rise in deaths involving antiepileptic, sedative-hypnotic, antiparkinsonism and psychotropic drugs, particularly intentional overdoses among females, highlights the need for sex-based interventions.