Background
Poor mental health contributes to poor HIV prevention, treatment and care outcomes. This paper documents factors associated with psychological distress among men who have sex with men (MSM) in Cambodia and discusses potential ways in which routine mental health management could be integrated into HIV services.

Methods
A cross-sectional study was conducted in 2014 among 394 MSM randomly selected from two provinces using a two-stage cluster sampling method. A structured questionnaire was used to assess psychological distress, sexual behaviors, substance use, adverse childhood experiences and family dysfunction. Multivariate logistic regression analysis was performed to explore factors associated with levels of psychological distress.

Results
In total, 10.7 % of the respondents reported having suicidal thoughts and 6.6 % reported having attempted to commit suicide in the past three months, while 38.8 % had a higher level of psychological distress (GHQ-12 > 3), which indicates poor mental health. Higher levels of psychological distress were independently associated with older age (AOR = 1.09, 95 % CI 1.03–1.14), alcohol use (AOR = 3.3, 95 % CI 1.36–7.83), illicit drug use (AOR = 3.53, 95 % CI 1.12–11.18), poor self-reported quality of life (AOR = 7.45, 95 % CI 1.79–3.04), and reduced condom use at last sex (AOR = 0.40, 95 % CI 0.21–0.73). MSM with higher levels of psychological distress were significantly more likely to report that a family member said hurtful things to them (AOR = 1.80, 95 % CI 1.10–2.97), a parent or guardian had been physically abused (AOR = 3.51, 95 % CI 1.86–6.62), and a family member had been mentally ill (AOR = 4.01, 95 % CI 2.06–7.81) when they were growing up.

Conclusions
In order to mitigate psychological distress among MSM in Cambodia, integration of mental health interventions within HIV programmes should be strengthened. To achieve optimal impact, these interventions should also address alcohol and other substance use, and low condom use among distressed MSM. In addition, training of clinical and non-clinical HIV service providers to screen for mental health symptoms, and subsequent provision of peer-based outreach and social support for MSM identified with psychological distress is required.