Global deaths linked to drug use disorders more than doubled between 1990 and 2021, despite a decline in new case rates, according to recently published findings.

Using data from the 2021 Global Burden of Disease study, investigators evaluated incidence, prevalence, mortality, and disability-adjusted life-years (DALY) for opioid, cannabis, cocaine, amphetamines, and other substance use disorders across 204 countries and territories.

“The consequences of [drug use disorders] DUD are multifaceted, spanning individual and societal levels,” wrote lead study author Yujuan Liu, PhD, of Jinshan Hospital, Fudan University, and colleagues. “Critically, unaddressed DUDs undermine progress toward United Nations Sustainable Development Goal 3 (good health and well-being for all at all ages) by perpetuating health disparities and straining public health systems,” they added.

The analysis showed that global incident DUD cases increased 36% (95% uncertainty interval [UI] = 31%–40%) from 10.04 million to 13.61 million in 2021, while deaths rose 122% (95% UI = 100%–149%) from 61,774 to 137,278. DALYs increased 75% (95% UI = 65%–85%), from 8.91 million to 15.56 million, despite an 8% decline in the age-standardized incidence rates (184.31 to 169.39 per 100,000 individuals). Mortality rates increased 31% (1.26 to 1.65 per 100,000 individuals), and DALYs rose 15% (166.44 to 190.97 per 100,000 individuals).

North America experienced the sharpest rise, with an 11.2-fold increase in deaths (6,125 to 74,451). East Asia, by contrast, recorded a 15% decrease in incident cases. Opioid-related DALYs increased 32% (103.69 to 137.15 per 100,000 individuals), and cocaine-related mortality more than doubled (108%; 0.07 to 0.15 per 100,000 individuals). Amphetamine use disorders declined 40% in incidence but showed a 28% rise in mortality.

Using Bayesian meta-regression (DisMod-MR 2.1) and age-period-cohort modeling, the investigators found that men aged 20 to 24 years had 1.35 times higher incidence compared with women (386.01 vs 285.59 per 100,000 individuals), with mortality peaking among men aged 25 to 29 years (3.45 vs 1.12 per 100,000 individuals). DALYs correlated positively with the Socio-demographic Index (Spearman r = 0.70), indicating a disproportionate burden in high-income regions.

Study limitations included underreporting in low- and middle-income countries, reliance on modeled estimates because of limited primary data, and underestimation of mortality linked to certain substances such as cannabis. The investigators also noted that polysubstance use interactions weren't fully captured, and intervention effects weren't comprehensively evaluated.

This study was supported by the key construction project on clinical pharmacy (1229) at Jinshan Hospital Affiliated to Fudan University. The study authors reported no commercial or financial relationships that could be construed as potential conflicts of interest.

Source: Frontiers in Psychiatry