A Global Burden of Disease analysis estimated that U.S. age-standardized substance-use disorder disability-adjusted life-year rates rose 213.5% from 1990 to 2019, with opioid use disorders producing the steepest increase and the largest state-level burden.1 Research Highlights U.S. cases rose sharply: prevalent substance-use disorder cases increased from 12.6 million in 1990 to 19.5 million in 2019.1 …
A 2026 preprint combining 2,189 university participants with 477 clinical patients with problematic sexual behavior found a gender-specific self-harm signal: women with problematic sexual behavior had higher non-suicidal self-injury risk, but clinical severity of problematic sexual behavior did not predict NSSI inside the patient cohort.1 Research Highlights Total sample was 2,666 people: Jiang et al. …
Chronic stress is a candidate mechanism for both depression and addiction risk. A 2026 mouse study found that 28 days of unpredictable chronic mild stress increased striatal dopamine D1 receptor binding by 22–48% across nearly every region examined, plus more selective D2 receptor increases — pointing to a stress-driven shift in reward signaling that may …
A 2026 BRFSS analysis involving 4,071 U.S. adults who used cannabis and either smoked cigarettes, vaped nicotine, or did both found a strong modality match: people who vaped tobacco were much more likely to vape cannabis than to smoke cannabis.1 For addiction and harm-reduction assessment, the pattern is a route-specific risk signal because smoking, vaping, …
A 2026 ABCD Study preprint found that teen substance-use initiation prediction improved more when models included changing risk over time than when they simply switched from logistic regression to multi-task learning.1 Dynamic models raised AUROC by 0.044 to 0.062 in multi-task learning and by 0.050 to 0.084 in logistic regression, which makes timing the main …
Australian coronial data show that fatal poisonings involving new psychoactive stimulants and hallucinogens were rarely single-drug events. In 70 toxicology-confirmed deaths from 2007 through 2025, 92.9% involved other psychoactive drugs and 75.7% involved multiple stimulants or hallucinogens. Research Highlights Fatal cases were usually polysubstance cases: 65 of 70 deaths (92.9%) had psychoactive drugs beyond the …
A 2026 rat study found that 21 days of late-adolescent tetrahydrocannabinol (THC) exposure produced adult anxiety-like behavior in the elevated plus maze and weaker novel object recognition than vehicle exposure. The controlled animal result gives a biologically anchored model for why repeated high-THC exposure during development remains a real concern.1 Research Highlights Late-adolescent THC exposure …