WASHINGTON: People who survive cancer when they are teenagers or young adults are more likely than their peers who never had cancer to engage in risky behaviours like smoking later on, a US study said Monday.

They also are more likely to be overweight and have mental health issues and financial problems than their cancer-free counterparts, said the research in the journal Cancer, a peer-reviewed publication of the American Cancer Society.

“There are a lot of factors that play into it,” said lead author Eric Tai of the US Centres for Disease Control and Prevention's Division of Cancer.

“Part of it may be that adolescent and young adult cancer survivors are not aware of their medical history and they are not aware of the long-term risks associated with their cancer and their cancer treatment,” he told AFP.

“Because of that, they may engage in behaviours not knowing the long-term consequences of them.”

Also, people diagnosed with cancer between age 15 and 29 are developmentally very different than older cancer survivors, and so they tend to cope with their illnesses in ways that elders might not, he added.

Finally, they are not being tracked by health care providers as well as younger and older patients.

“There hasn't been very good follow-up of cancer survivors in this group in terms of screening, health checks, those kinds of things looking for early signs of problems that may come up and also looking at risk behaviors.”

The data for the study came from a nationwide survey known as the 2009 Behavioural Risk Factor Surveillance System (BRFSS).

Researchers identified people who were diagnosed with cancer when they were adolescents or young adults, and compared their responses to questions about their health to a group of 345,592 cancer-free respondents.

A large majority of the young cancer survivors group was female—81 per cent—and the most commonly reported type of cancer was cervical (38 per cent) followed by other female reproductive cancers (13 per cent) and melanoma (nine per cent).

The young survivors were more likely to smoke (26 per cent compared to 18 per cent in the group that never had cancer) and more of them were obese (31 per cent versus 27 per cent).

Twice as many reported being disabled (36 per cent compared to 18 per cent) and 24 per cent said they were in poor physical health while just 10 per cent of the cancer-free group said the same.

Poor mental health was mentioned by 20 per cent of young cancer survivors, twice as many as in the control group, and they were also more likely to forgo medical care because of the cost (24 per cent versus 15 per cent).

Adolescent and young adult cancer survivors also reported higher rates of heart disease, high-blood pressure, asthma and diabetes.

Many of these problems could be avoided with better follow-up care, Tai said.

“Health care providers really need to be aware of established follow-up guidelines, which include information on potential latent effects, risk factors, screening and evaluation, counselling, and other interventions.”