Prevalence and correlates of substance use among transgender adults: A systematic review

Highlights

• Methodological limitations preclude substance use prevalence estimation among trans people.

• Intersectionally disadvantaged trans people are overrepresented in the literature.

• Trans women appear to be at greatest risk of substance use and related problems.

• Substance use correlates identified among trans people support minority stress theories.

• More research exploring the influence of non-binary and transmasculine genders is needed.

Abstract

Introduction

Minority stress theories suggest that high rates of discrimination experienced by transgender people are precipitants of substance use. This risk is likely exacerbated by an inadequate provision of trans-inclusive substance misuse services. However, the exclusion of transgender people from the general substance misuse literature makes it difficult to determine the extent to which transgender status influences substance use. A systematic review was undertaken to better understand the prevalence, patterns and correlates of substance use among this group.

Methods

In accordance with the PRISMA guidance, a literature search was conducted to 29th May 2019 on PubMed, PsycINFO, Embase and Global Health databases. Primary quantitative studies, published in English, that reported the prevalence, patterns or correlates of substance use by transgender people were included, with no restriction on methodological design.

Results

653 unique records were identified, and 41 studies were included. Half the studies reported on both transgender men and transgender women and half transgender women only. There was high and excess prevalence of substance use among transgender compared with cisgender people, but insufficient evidence to estimate prevalence or quantify the risk for substance use. Correlates of substance use included transphobic discrimination or violence, unemployment and sex work, gender dysphoria, high visual gender non-conformity and intersectional sexual minority status.

Conclusions

The sparse findings lend support to the minority stress model. However, the overreliance of the literature on disproportionate investigation of transgender women with multiple intersectional disadvantages, means there are significant gaps regarding the wider transgender community. To ensure substance use treatment services are inclusive, gender identity should be recorded and targeted interventions available. Clinicians should be aware of the multiple, complex drivers of substance use and be prepared to ask about substance use and offer support. Given the high prevalence of trauma experienced by transgender people, trauma-informed psychosocial interventions may be useful in the management of problematic substance use in transgender adults.

Introduction

Gender identity is a term which describes a person’s understanding of themselves as a woman, man, a combination of both or as neither (American Psychological Association, 2015, Campaign, 2019). How one’s gender identity relates to that associated with their birth sex determines whether they are understood to be cisgender or transgender (American Psychological Association, 2015). Transgender individuals have gender identities which differ, to varying degrees, from the gender constructs of their birth-assigned sex. Cisgender refers to individuals whose gender identity matches the sex that was assigned to them at birth. For example, a cisgender woman is a person assigned female at birth who also identifies as a woman (American Psychological Association, 2015, Bockting, 2009, Bockting et al., 2013, Hendricks and Testa, 2012, Mayer et al., 2008).

Many transgender people identify within a male/female binary. A transgender man is an individual assigned female at birth who identifies as a man [or masculine]; a transgender woman was assigned male at birth but identifies as a woman [or feminine] (Hendricks & Testa, 2012). However, not all transgender people identify with these binary (male/female) gender categories, but may identify instead with a non-binary identity, using terms such as genderqueer, gender non-conforming or two-spirit (American Psychological Association, 2015, Carroll et al., 2002, Eyler, 2007, Hendricks and Testa, 2012). Agender individuals are those who do not identify with any particular gender (American Psychological Association, 2015).

The motivation to understand the prevalence of substance use among transgender people is threefold. Firstly, substance use is a socially patterned behaviour and the quantity and frequency of consumption as well as the risk of problematic use have been demonstrated to differ between cisgender men and women (Grant et al., 2015, Nolen-Hoeksema, 2004, Wilsnack et al., 2000). In addition, more subtle differences related to gender expression have been demonstrated among sexual minority (non-heterosexual) women, whereby those who identify as ‘butch’ have been shown to drink larger quantities, more frequently than those who identify as ‘femme’, indicating that differences are likely to be present among transgender people that could provide a more nuanced understanding of how gender and its expression influence substance use (Rosario, Schrimshaw, & Hunter, 2008).

Secondly, transgender people represent a small, vulnerable minority, making up an estimated 0.4–0.6% of the adult population (Flores et al., 2016, Meerwijk and Sevelius, 2017, Reisner et al., 2016). Stigma and violence against transgender people are common and the injurious nature of experiencing this kind of discrimination is well established and has been associated with engaging in health risk behaviours such as substance use as a means to cope (Kidd et al., 2011, Link and Phelan, 2006, Stieglitz, 2010, Stotzer, 2009).

The Minority Stress Model formalises this association and asserts that minority or marginalised groups who are chronically exposed to discrimination will experience worse mental health outcomes, particularly related to suicidality and substance use (Meyer, 2003). While there is a wealth of evidence supporting how this model applies to sexual minorities (Bloomfield et al., 2011, Demant et al., 2016, Kerr et al., 2014, Lea et al., 2013, Marshal et al., 2008, Ross et al., 2014), less is known about its applicability to transgender people.

Thirdly, transgender people face significant healthcare disparities. Considering the UK as an example, there are >7500 transgender people on waiting lists, up to three years long, to be assessed by Gender Identity Clinics (Torjesen, 2018). Consequently, a great many transgender people must find a way to cope with gender dysphoria and there is a risk that substances may be used to self-medicate. A recent study found that transgender people are more likely than cisgender people to want help to reduce their substance use (Connolly et al., 2020). Despite this, healthcare disparities for transgender people are particularly pronounced in substance use disorder services. There has long been recognition of the need for specialist substance use disorder services for transgender people, yet literature describing such interventions is sparse (Cochran and Cauce, 2006, Eliason, 2000, Glynn and van den Berg, 2017, Lombardi and van Servellen, 2000, Nuttbrock, 2012, Sperber et al., 2005).

Despite these societal and treatment inequalities, previous mainstream substance use research has excluded transgender participants (Flentje, Bacca, & Cochran, 2015). Consequently, there is a paucity of evidence relating to the prevalence, patterns and correlates of substance use among transgender people. This review seeks to fill this gap in the literature, to better inform treatments and service delivery, by:

• Identifying clinically meaningful correlates of substance use within this population.

• Describing the pattern and prevalence of substance use among transgender people.

• Identifying limitations of the current literature and making recommendations for further research moving forward.