The Cyclical and Evolving Nature of Methamphetamine Use: An Evaluation of Near Real-time Urine Drug Test Results

To determine methamphetamine positivity and copositivity with other drugs in urine drug test (UDT) results geographically through time.

This cross-sectional study of UDT results from January 1, 2014, through December 31, 2019, included patient specimens submitted by health care professionals across the United States. The analysis used LC-MS/MS to detect cocaine, heroin, alcohol, marijuana and nonprescribed methamphetamine, fentanyl, methadone, buprenorphine, benzodiazepines, and other opioids. Logistic regression was used to evaluate association of demographic features and model yearly methamphetamine detection patterns across US census divisions. Odds ratios (OR) from logistic modeling were used to evaluate the impact of methamphetamine positivity on the spatio-temporal detection patterns of additional nonprescribed or illicit drugs.

The probability of being positive for methamphetamine increased nationally from 0.010 [0.010-0.011] in 2014 to 0.044 [0.042-0.046] in 2019, a 340% increase after correction for demographic covariates. The highest predicted positivity rate was in male patients, 25- to 34-years-old, from the West North Central division and from substance use disorder treatment centers. Nationally, copositivity ORs for fentanyl, heroin, and other opioids with methamphetamine were highest in 2019. Increases in ORs from 2014 through 2019 were statistically significant for heroin (P = 0.024) and fentanyl (P = 0.0085). Copositivity ORs for methamphetamine and other substances varied by census division.

The probability of being positive for methamphetamine in UDT increased nationwide between 2014 and 2019. Not all census divisions are increasing at the same rate. Copositivity with additional substances is increasing in some census divisions, which further increases the risk of overdose and poor treatment outcomes.