Direct-To-Definitive Urine and Oral Fluid Test Results for Unscreened and Rarely Screened Drugs in Individuals Applying for Methadone Treatment in 7 U.S. States

The standard protocol in addiction treatment/pain management is to conduct immunoassay screens for major drugs subject to misuse, followed by confirmatory testing of positive results. However, this may miss unscreened or rarely screened drugs that could pose risks, especially to polydrug users. We sought to determine the prevalences of unscreened/rarely screened drugs in a sample of individuals misusing drugs in 7 U.S. states, and to compare the results of urine vs. oral testing for these drugs by direct-to-definitive liquid chromatography/tandem mass spectrometry (LC-MS-MS). The five drugs with the highest prevalences were: gabapentin (16.8%), quetiapine (6.2%), chlorpheniramine (5.3%), hydroxyzine (4.9%), and ephedrine (3.5%). All have clinical significance as indicated by severity of possible side effects, interactions with other drugs, and/or misuse potential. Drugs were generally detected more frequently in oral fluid than urine, but gabapentin was more frequently detected in urine. The prevalences of the included drugs seem high enough, and their clinical significance important enough, to warrant consideration of expanding clinical drug test panels, either by direct-to-definitive testing or the addition of selected immunoassay screens when available. Oral fluid was usually more suitable than urine as the test matrix, given the higher rates of detection in oral fluid for most substances included in this study.

Combination prevention and HIV: a cross-sectional community survey of gay and bisexual men in London, October to December 2016

Background

Men who have sex with men (MSM) are at risk of HIV and are an important population to monitor and ameliorate combination prevention efforts.

Aim

To estimate HIV prevalence and identify factors associated with frequent HIV testing (≥ 2 HIV tests in the last year) and pre-exposure prophylaxis (PrEP) use among MSM in London.

Methods

For this cross-sectional study, MSM recruited from 22 social venues provided oral-fluid samples for anonymous HIV antibody (Ab) testing and completed a questionnaire. Factors associated with frequent HIV testing and PrEP use were identified through logistic regression.

Results

Of 767 men recruited, 545 provided an eligible oral specimen. Among these, 38 MSM (7.0%) were anti-HIV positive including five (13.2%; 5/38) who reported their status as negative. Condomless anal sex within the previous 3 months was reported by 60.1% (412/685) men. Frequent HIV testing was associated with, in the past year, a reported sexually transmitted infection (adjusted odds ratio (AOR): 5.05; 95% confidence interval (CI): 2.66–9.58) or ≥ 2 casual condomless partners (AOR 2–4 partners: 3.65 (95% CI: 1.87–7.10); AOR 5–10 partners: 3.34(95% CI: 1.32–8.49). Age ≥ 35 years was related to less frequent HIV testing (AOR 35–44 years: 0.34 (95% CI: 0.16–0.72); AOR ≥ 45 years: 0.29 (95% CI: 0.12–0.69). PrEP use in the past year was reported by 6.2% (46/744) of MSM and associated with ≥ 2 casual condomless sex partners (AOR: 2.86; 95% CI: 1.17–6.98) or chemsex (AOR: 2.31; 95% CI: 1.09–4.91).

Conclusion

This bio-behavioural study of MSM found high rates of behaviours associated with increased risk of HIV transmission. Combination prevention, including frequent HIV testing and use of PrEP, remains crucial in London.