Owing to discrimination and stigma associated with sexual minorities, depressive symptoms are more common among those who identify as lesbian, gay, bisexual, not exclusively heterosexual, or not sure of their sexual orientation from age 10, and continue throughout their early adulthood, say researchers.

The observational study, published in The Lancet Child and Adolescent Health journal, showed that the adolescents from the sexual minority group are four times more likely to report self-harm at ages 16-21 years than their heterosexual peers, and are at higher risk of depressive symptoms from as young as 10 years old.

"It is very concerning that despite changes in public perceptions and attitudes, sexual-minority youth remain at increased risk of long-term mental health problems," said lead researcher Gemma Lewis from University College London, UK. "Our findings underscore the importance of mental health problems before conscious self-identification and labelling of sexual-minority orientation. It is imperative that we find new ways to reach these adolescents and that they are able to access high-quality support services from a young age," Lewis added.

Further, while depressive symptoms developed faster during adolescence and continued into young adulthood, it tend to decline from age 18. This decline could be the result of social and psychological changes such as increased independence or changes in peer groups, the researchers suggested.

Since the study is observational, so no firm conclusions can be drawn about the cause and effect but the poorer mental health reported by sexual minorities may in part be due to the potentially hostile and stressful social environments created by the stigma, prejudice, and discrimination they face, they noted.

Reducing stigma and discrimination could, therefore, provide a pathway to primary prevention of mental disorders by reducing the burden of disease, improving public health and reducing health inequities. "... the findings highlight the urgent need for policy makers, public health researchers, health-care professionals, and educators to join forces to address the underlying causes of this inequity and reduce the burden of disease on vulnerable young people," said Rohan Borschmann from the Murdoch Children's Research Institute in Melbourne, Australia. For the study, the team analysed data on 4,843 adolescents who reported their sexual orientation at 16 years of age.