Under-reporting of Risky Drug Use Among Primary Care Patients in Federally Qualified Health Centers.

OBJECTIVE

The Affordable Care Act encourages integration of behavioral health into primary care. We aim to estimate the level of under-reporting of drug use in federally qualified health centers (FQHCs) among self-reported risky drug users.

METHODS

Adult patients in the waiting rooms of 4 FQHCs who self-reported risky drug use on the screening instrument World Health Organization's Alcohol, Smoking and Substance Involvement Screening Test (score 4-26), who participated in the "Quit Using Drugs Intervention Trial," submitted urine samples for drug testing. Under-reporters were defined as patients who denied use of a specific drug via questionnaire, but whose urine drug test was positive for that drug. Descriptive statistics, Pearson chi-square test, and logistic regression were used for analysis.

RESULTS

Of the 192 eligible participants, 189 (96%) provided urine samples. Fifty-four samples were negative or indeterminate, yielding 135 participants with positive urine drug tests for this analysis: 6 tested positive for amphetamines, 18 opiates, 21 cocaine, 97 marijuana. Thirty patients (22%) under-reported drug use and 105 (78%) reported drug use accurately. Under-reporting by specific substances was: amphetamines 66%, opiates 45%, cocaine 14%, and marijuana 7%. Logistic regression revealed that under-reporting of any drug was associated with history of incarceration and older age (odds ratios 2.6 and 3.3, respectively; P < 0.05).

CONCLUSIONS

Under-reporting of drug use is prevalent even among self-reported drug users in primary care patients of FQHCs (22%), but varied considerably based on the substance used. Further research is indicated to assess the extent of under-reporting among all primary care patients, regardless of their self-reported drug use status.