BACKGROUND: Given the increased use of psychoactive substances on the United States-Mexico border, a binational study (Tijuana, Mexico-Los Angeles, USA) was conducted to identify the prevalence of substance use in primary care settings. OBJECTIVES: To compare the prevalence and characteristics of patients at risk for substance use disorders in Tijuana and East Los Angeles (LA) community clinics with special attention paid to drug use. METHODS: This was an observational, cross-sectional, analytical study, comparing substance use screening results from patients in Tijuana and LA. The settings were 2 community clinics in LA and 6 in Tijuana. Participants were 2,507 adult patients in LA and 2,890 in Tijuana eligible for WHO Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) screening during March-October 2013. Patients anonymously self-administered the WHO ASSIST on a tablet PC in the clinic waiting rooms. RESULTS: Of eligible patients, 96.4% completed the ASSIST in Tijuana and 88.7% in LA (mean 1.34 minutes and 4.20 minutes, respectively). The prevalence of patients with moderate-to-high substance use was higher in LA than Tijuana for each substance: drugs 19.4% vs. 5.7%, alcohol 15.2% vs. 6.5%, tobacco 20.4% vs. 16.2%. LA patients born in Mexico had 2x the odds and LA patients born in the United States had 6x the odds of being a moderate-to-high drug user compared to Tijuana patients born in Mexico. CONCLUSIONS: Moderate-to-high drug use is higher in LA than in Tijuana but rates are sufficiently high in both to suggest that screening for drug use (along with alcohol and tobacco use) should be integrated into routine primary care of community clinics in both cities.

Background

QUIT is the only primary care-based brief intervention that has previously shown efficacy for reducing risky drug use in the United States (Gelberg et al., 2015). This pilot study replicated the QUIT protocol in one of the five original QUIT clinics primarily serving Latinos.

Design

Single-blind, two-arm, randomized controlled trial of patients enrolled from March-October 2013 with 3-month follow-up.

Setting

Primary care waiting room of a federally qualified health center (FQHC) in East Los Angeles.

Participants

Adult patients with risky drug use (4-26 on the computerized WHO ASSIST): 65 patients (32 intervention, 33 control); 51 (78%) completed follow-up; mean age 30.8 years; 59% male; 94% Latino.

Interventions and measures

Intervention patients received: 1) brief (typically 3-4 minutes) clinician advice to quit/reduce their risky drug use, 2) video doctor message reinforcing the clinician's advice, 3) health education booklet, and 4) up to two 20-30 minute follow-up telephone drug use reduction coaching sessions. Control patients received usual care and cancer screening information. Primary outcome was reduction in number of days of drug use in past 30days of the highest scoring drug (HSD) on the baseline ASSIST, from baseline to 3-month follow-up.

Results

Controls reported unchanged HSD use between baseline and 3-month follow-up whereas Intervention patients reported reducing their use by 40% (p<0.001). In an intent-to-treat linear regression analysis, intervention patients reduced past month HSD use by 4.5 more days than controls (p<0.042, 95% CI: 0.2, 8.7). Similar significant results were found using a complete sample regression analysis: 5.2 days (p<0.03, 95% CI: 0.5, 9.9). Additionally, on logistic regression analysis of test results from 47 urine samples at follow-up, intervention patients were less likely than controls to test HSD positive (p<0.05; OR: 0.10, 95% CI: 0.01, 0.99).

Conclusions

Findings support the efficacy of the QUIT brief intervention for reducing risky drug use.