BACKGROUND: Sexual and gender minorities, collectively known as LGBTQIA+ individuals, experience disproportionate mental health disparities compared to their heterosexual/cisgender peers.

AIMS: The aim of this systematic review was to synthesize high-quality evidence from previously published systematic reviews on mental health in the LGBTQIA+ population.

METHOD: PubMed was searched for systematic reviews on LGBTQIA+ mental health, published by September 1st, 2024. For each mental health outcome, a narrative synthesis of the findings was performed. Additionally, when included reviews reported case-control data suitable for pooled analysis, network meta-analyses with random-effects models were conducted to estimate the Odds Ratios (ORs) and 95% confidence intervals (95% CIs) for mental disorders across sexual and gender groups.

RESULTS: Twenty systematic reviews were included, accounting for 5,164,641 LGBTQIA+ individuals. These focused on the following mental health outcomes: major depressive disorder (MDD,  = 7), eating disorders (ED,  = 5), anxiety disorders (AD,  = 5), substance use disorder (SUD,  = 4), alcohol use disorder (AUD,  = 1), post-traumatic stress disorder (PTSD,  = 1), and suicidality ( = 11), all resulting more prevalent among LGBTQIA+ individuals compared to the general population. Network meta-analysis was possible only for suicide attempts (SA), finding the highest risk among bisexual individuals (OR = 6.43, 95% CI [4.43; 9.34]), followed by lesbian and gay individuals (OR = 4.54, 95% CI [3.42, 6.03]), sexual and gender minorities analyzed together (OR = 4.32, 95% CI [3.52, 5.30]), and transgender individuals (OR = 3.61, 95% CI [2.78, 4.67]). Geographical differences were also found, with transgender individuals being the group with the highest SA risk in Europe (OR = 7.22, 95% CI [4.83, 10.81]) and the lowest SA risk in Asia (OR = 1.84, 95% CI [0.68, 5.03]), suggesting potential socio-cultural influences or differences in participant selection.

CONCLUSIONS: LGBTQIA+ individuals experience significant mental health challenges compared to the general population. To reduce these disparities, more inclusive policies, supportive social environments, affirmative mental health care, and ongoing research into minority stressors and protective factors are essential.