Age, period, and cohort trends of substance poisoning, alcohol-related disease, and suicide deaths in Australia, 1980-2019

PurposeDeaths due to substance poisoning, alcohol-related disease, and suicide pose a critical public health issue, and have been categorized as "deaths of despair" in the US. Whether these deaths represent a distinct phenomenon requires exploration, particularly in other countries.MethodsThis retrospective observational study examines age-period-cohort trends of (combined and cause-specific) substance poisoning, alcohol-related disease, and suicide deaths among Australians aged >= 15-years that occurred between 1980 and 2019 and compares trends between males and females.ResultsCombined mortality rates were initially (1980-1999) relatively stable, reflecting a reduction in alcohol-related disease deaths offset by an increase in substance poisoning deaths. A decline (2000-2006) and subsequent increase (2007-2019) in combined rates were primarily attributable to corresponding changes in both substance poisoning and suicide deaths among males. Distinct age-period-cohort trends were observed between cause of death sub-types, with net drifts: increasing for male (net drift [95% CI]: 3.33 [2.84, 3.83]) and female (2.58 [2.18, 2.98]) substance poisoning deaths; decreasing among male alcohol-related disease (- 1.46 [- 1.75, - 1.16]) and suicide deaths (- 0.52[- 0.69, - 0.36]); and remaining relatively stable for female alcohol-related disease (- 0.28 [- 0.66, 0.09]) and suicide deaths (- 0.25 [- 0.52, 0.01]).ConclusionsAlthough combined age-specific trends were relatively stable over the study period, different and distinct patterns were observed within cause-specific deaths, challenging the notion that these causes of death represent a distinct epidemiological phenomenon. These data indicate a critical need to review the appropriateness of guidance for clinical practice, prevention strategies, and policy initiatives aimed at preventing future deaths.