Positive Urine Drug Screens and External Mortality in Teenagers Who Present for Medical Care.

Abstract

Objective: To examine whether a positive urine drug of abuse screen in youth who receive medical care is associated with subsequent risk of external mortality (eg, overdose, suicide, homicide, accident).Methods: This was a population-based retrospective cohort study of all Olmsted County (Minnesota) residents who were 13-18 years of age at the time of urine drug screen (UDS) testing (January 1, 1999, to November 28, 2012). Cox regression models were used to examine the relationships between having a positive UDS and external mortality, adjusted for sex, race, age, alcohol exposure, psychiatric diagnoses as defined by the International Classification of Diseases (ICD-9/ICD-10), and medical setting of UDS testing. Separate analyses were done for (1) overall UDS results, (2) tetrahydrocannabinol (THC), and (3) cocaine.Results: Of the 2,772 teenagers included in this study (47.2% male), a total of 26 died of external causes during a median follow-up period of 11.8 years. Testing positive for any illicit substance was not associated with significantly increased risk of external mortality (hazard ratio [HR] = 1.9; 95% CI, 0.9-4.2). Testing positive for cocaine was associated with significantly increased risk of external mortality (HR = 7.0; 95% CI, 1.9-25.0). Testing positive for THC was associated with a marginally significantly increased risk of external mortality (HR = 2.1; 95% CI, 1.0-4.7); however, when cocaine was added as a covariate in the analysis, the relationship between THC-positive UDS and mortality was still elevated but was no longer statistically significant (HR = 1.8; 95% CI, 0.8-4.1).Conclusions: History of cocaine-positive UDS may help identify a population of young people who are at high risk of premature death.