People who identify as transgender or gender nonconforming may have higher than average rates of poor or fair health, a new study suggests.

“There is little research on this population, because people haven’t been asking them to identify themselves,” said lead author Dr Carl Streed Jr, of Brigham and Women’s Hospital in Boston.

Transgender describes people whose gender identity differs from the sex they were assigned at birth, while gender nonconforming refers to people who don’t identify solely as male or female.

In a 2015 report, the US National Institutes of Health highlighted the need for better understanding of the lesbian, gay, bisexual and transgender communities.

“These are patients and individuals and communities that need our attention at this point and we should be working with them to better identify what’s going on in their lives,” Streed said.

For the new study, the researchers used data collected in 2014 and 2015 as part of the US Centers for Disease Control and Prevention’s Behavioural Risk Factors Surveillance System. In 2013, the CDC created a series of questions about gender identity, which had been adopted by 28 states and territories when the researchers analysed their data.

There is research showing that transgender and gender nonconforming people are at an increased risk for mental health problems

As reported online on May 30 in JAMA Internal Medicine, altogether the researchers had survey responses from 315,893 people, including 1,443 who identified as transgender or gender nonconforming. About 23 per cent of transgender and gender nonconforming people reported poor or fair health, compared to about 17 per cent of people who did not identify as a gender minority.

Transgender and gender nonconforming people were also more likely to report limitations and problems with memory, concentration and decision-making.

Compared to people who did not identify as a gender minority, those who did were younger and more likely to be low income, unemployed, uninsured, overweight or have unmet medical needs. They were also more likely to report depression.

People identifying as transgender or gender nonconforming were less likely to be non-Hispanic white, partnered, parents or English-speaking.

The health disparities between transgender and gender nonconforming people and others remained significant even after the researchers adjusted the findings for factors that may influence health, such as health insurance status and health behaviours.

Streed said he can only speculate as to why transgender and gender nonconforming people appear to be worse off, but it could be due to minority stress and issues with resilience.

Reuters Health has reported elsewhere this year on research suggesting that doctors in many specialties are often unprepared to account for patients' needs related to their gender identity.

This new study starts to scratch the surface of the topic, said Dr John Cullen, director of diversity and inclusion at the Clinical and Translational Science Institute at the University of Rochester Medical Centre in New York.

“There are disparities there that we’re not seeing in this paper,” said Cullen, who was not involved with the new research.

For example, he said, there is research showing transgender and gender nonconforming people are at an increased risk for mental health problems and other health conditions like HIV.