Determination of the Profile of New Psychoactive Substances Among Users from the Homeless Population: A Mixed-Methods Approach.

Abstract

The emergence of new psychoactive substances (NPS) among the homeless population has been highlighted as a growing concern in the recent years. NPS have plagued the homeless population in recent years creating a number of associated economic and social issues. The majority of previous research have focused on using either qualitative or quantitative techniques; however, few studies have used mixed-methods approach. Therefore, this thesis has complemented the gap in previous research by using a mixed method approach to determine the profile of NPS among the homeless population. Two quantitative studies, including a systematic review and semi-structured questionnaire that enabled to understand the prevalence of NPS in the UK and worldwide, were conducted. Additionally, one qualitative study was performed and comprised Twitter analysis that confirmed NPS encountered among the homeless and their effects from the views of the public and service providers. The aforementioned three studies determined NPS used among the homeless population and flagged the impurities in them. NPS and impurities were further confirmed by chemical analysis conducted using Fourier transform infrared and Raman spectroscopy. Substantial information obtained in this thesis, not reported in previous literature, demonstrated the potential for mixed-method approach in giving a greater insight into experience of NPS among the homeless. The systematic review highlighted the surge in synthetic cannabinoid receptor agonists (SCRAs) among the homeless in the UK, USA and Canada that occurred after 2016; whereas alcohol, cocaine and heroin had been more prevalent prior to 2016. Continued SCRAs use contributed to long-term adverse events especially anxiety, depression and psychosis. In this respect, the findings of the questionnaire confirmed the latter findings related to SCRAs use in the homeless population. Homeless in the UK reported short and long-term adverse events linked to SCRAs use that were readily accessible to them but not always as pure substances. Hence, they had access to SCRAs in different matrices including herbal, e-liquids and paper. The variable effects experienced upon SCRAs use further flagged their unknown purity. This was further explored in the Twitter study that reported variable effects experienced to drugs in different geographical area. Subsequently, the spectroscopic chapters identified the different concentrations of SCRAs impregnated into paper matrices. In summary, the findings from this thesis contributed to the scientific literature by informing policy makers, law enforcement, medical practitioners and homeless service providers about the profile of NPS use among the homeless population.