Why Gender Matters in the Study and Treatment of Substance Use Disorders

This SCP Blog by Dr. Kathryn McHugh discusses a recent article published in Clinical Psychology Review about why gender matters in the study and treatment of substance use disorders.

For many years, knowledge on the nature and treatment of substance use disorders was based on research conducted in males. The vast majority of research on substance use in women has been published only in the last 3 decades (Greenfield et al., 2007). Understanding the impact of substance use disorders on women is more urgent than ever, as women and girls represent an increasing proportion of those with substance use disorders both in the United States and worldwide. This shrinking gender gap is particularly evident in adolescents; boys and girls drink, binge drink, and use illicit drugs at similar rates.

Understanding of how substance use disorders differ between men and women is critical to optimizing prevention and treatment, and to ensuring that treatments initially tested in men are also safe and effective for women. My colleagues Dr. Shelly Greenfield, Victoria Votaw, Dr. Dawn Sugarman and I conducted a critical review of sex and gender differences in substance use disorders, published in Clinical Psychology Review (McHugh, Votaw, Sugarman, and Greenfield, 2017). In this blog post we highlight some of our findings.

Although there are many similarities between males and females, there are also significant differences ranging from the biological effects of substances of abuse on the body, to the functional impact, course, and treatment of substance use disorders.

Biological sex differences are complex and multisystemic, and include endocrine, metabolic, and neural processes, among others. For example, sex differences in the enzyme that metabolizes alcohol in the stomach (alcohol dehydrogenase) results in higher concentrations of alcohol in the blood in women relative to men. Moreover, ovarian hormones, such as progesterone, appear to play a role in the effects of substances, such as the degree to which substances are experienced as pleasant or unpleasant and may also play a role in treatment response.

Among the most well-established differences between men and women is that women tend to experience more significant functional consequences of substance use disorders, such as impairment in family and social relationships. Women are more likely than men to report using substances to self-medicate negative affect and are more likely to suffer from anxiety and depression than men. Thus, consideration of co-occurring psychiatric symptoms and disorders may be particularly relevant for women with substance use disorders.

Although men and women generally have similar outcomes following treatment, recent studies are beginning to identify differences in treatment response that may be critical to matching interventions based on gender. Research on smoking cessation suggests that women may respond better to varenicline, whereas men have a stronger response to nicotine replacement (Perkins & Scott, 2008; Smith et al., 2017). Furthermore, a promising new treatment approach is the use of gender-responsive interventions. Such treatments may use gender-specific format (e.g., all women’s group therapy) or content (e.g., therapeutic content specific to women). For example, the Women’s Recovery Group–developed by Dr. Shelly Greenfield and colleagues at McLean Hospital–is a manualized group therapy for women with substance use disorders that has demonstrated efficacy in two randomized trials (Greenfield, Trucco, McHugh, Lincoln, & Gallop, 2007; Greenfield et al., 2014).

Many important questions remain unanswered about ways in which biological, psychological, and sociocultural factors play a role in substance use disorders in males and females. Few clinical trials are large enough to detect gender differences in outcome or mechanisms of treatment effect, and gender-specific analyses are often not reported. Substance use disorders are also understudied in a number of subgroups of women, such as racial and ethnic minorities, older adults, and the LGBTQ population. Nonetheless, the rapidly growing research on substance use disorders in women has definitively answered the question: can results from studies of substance use disorders in males simply be generalized to females? That answer is a resounding no.

Reference Article

McHugh, R. K., Votaw, V. R., Sugarman, D. E., & Greenfield, S. F. (2017). Sex and gender differences in substance use disorders. Clinical psychology review.

Discussion Questions

  1. In addition to differences between men and women, there are also many differences among How might these various factors, such as race, ethnicity, sexual orientation, and medical and psychiatric comorbidity, impact the treatment of substance use disorders in women?
  2. What are the costs and benefits of gender-specific vs. mixed-gender clinical programming? Are there certain subgroups who might particularly benefit from one approach or the other?

Author Bio

Kathryn McHugh, Ph.D. is a clinical psychologist in the Division of Alcohol and Drug Abuse at McLean Hospital and an Assistant Professor at Harvard Medical School. Dr. McHugh is a clinical researcher and practitioner whose work focuses on the nature and treatment of anxiety and substance use disorders. Her research is currently funded by grants from the National Institute on Drug Abuse, including a 5-year grant to develop and test a novel cognitive-behavioral therapy for co-occurring opioid use disorder and anxiety disorders.

References Cited

Greenfield, S. F., Brooks, A. J., Gordon, S. M., Green, C. A., Kropp, F., McHugh, R. K., . . . Miele, G. M. (2007). Substance abuse treatment entry, retention, and outcome in women: A review of the literature. Drug and Alcohol Dependence, 86(1), 1-21. doi: 10.1016/j.drugalcdep.2006.05.012

Greenfield, S. F., Sugarman, D. E., Freid, C. M., Bailey, G. L., Crisafulli, M. A., Kaufman, J. S., . . . Fitzmaurice, G. M. (2014). Group therapy for women with substance use disorders: results from the Women’s Recovery Group Study. Drug and Alcohol Dependence, 142, 245-253. doi: 10.1016/j.drugalcdep.2014.06.035

Greenfield, S. F., Trucco, E. M., McHugh, R. K., Lincoln, M., & Gallop, R. J. (2007). The Women’s Recovery Group Study: a Stage I trial of women-focused group therapy for substance use disorders versus mixed-gender group drug counseling. Drug and Alcohol Dependence, 90(1), 39-47. doi: 10.1016/j.drugalcdep.2007.02.009

Perkins, K. A., & Scott, J. (2008). Sex differences in long-term smoking cessation rates due to nicotine patch. Nicotine & Tobacco Research, 10(7), 1245-1250. doi: 10.1080/14622200802097506

Smith, P. H., Weinberger, A. H., Zhang, J., Emme, E., Mazure, C. M., & McKee, S. A. (2017). Sex Differences in Smoking Cessation Pharmacotherapy Comparative Efficacy: A Network Meta-analysis. Nicotine & Tobacco Research, 19(3), 273-281. doi: 10.1093/ntr/ntw144