Trends in polysubstance use in the Croatian general population: evidence from 2011-2023 national surveys.

AIM: To examine the extent of polysubstance use in the general population of Croatia, determine trends in polysubstance use between 2011 and 2023, and identify distinct subgroups based on the patterns of polysubstance use and compare these subgroups across survey years. METHODS: Four studies were conducted between 2011 and 2023 on nationally representative samples of Croatian residents aged 15 to 64, with a total of 19 730 respondents, through face-to-face surveys in private households. Last-year substance use (tobacco, alcohol, cannabis, ecstasy, amphetamines, cocaine, and LSD) was assessed using the Croatian translation of the European Model Questionnaire. RESULTS: Across all four survey years, alcohol (71.8%-83.3%), tobacco (39.4%-43.7%), and cannabis (5.1%-10.2%) were the most commonly used substances in the Croatian general population. Last-year abstinence showed a declining trend between 2011 and 2023, single-substance use remained stable, and polysubstance use increased over this period. Latent class analysis identified three distinct subgroups: alcohol-only use, alcohol and tobacco use, and polysubstance use. Alcohol and tobacco use and polysubstance use classes increased in size from 2011 to 2023, with the polysubstance use class increasing from 0.9% in 2011 to 2.8% in 2023, alongside higher probabilities of cocaine and ecstasy use over time. CONCLUSION: Polysubstance use is a growing public health concern in Croatia. The trends of co-use of alcohol and tobacco and stimulants use with polysubstance use patterns were rising. These trends emphasize the need for further research and the development of targeted prevention and intervention efforts, accounting for distinct effects of polysubstance use and cultural specificities of Croatian society.