US researchers have found recreational cannabis use is lower among cancer patients than the wider population.

The study, published in the journal Cancer by Virginia Commonwealth University (VCU), analysed data from almost 20,000 people over a four-year period and found cannabis use peaked at 9% for cancer patients compared to 14% among non-sufferers.

Lead author Bernard Fuemmeler from VCU’s Massey Cancer Center said: “Even when we look at whether someone used cannabis over the four years of observation and we control for things like age and race, cancer patients are still not increasing their use over time like the general population. I would have expected them to have at least mirrored what was happening in the general population.”

Legalisation has had little impact on cancer sufferers’ cannabis use in the US

The research drew on data collected between 2013 and 2018 from the Population Assessment of Tobacco and Health (PATH), which tracks a representative sample of Americans to survey smoking behaviours, including tobacco and cannabis.

For people without cancer, cannabis use rose during the four-year PATH study period, which coincided with a wave of recreational legalisation across the US. However, the odds of a cancer patient using cannabis in the past year remained essentially static during the same timeframe.

Fuemmeler attributed this to greater health consciousness among those with a cancer diagnosis. He said: “There is that element of a life-changing moment when you have cancer. You have to be mindful of your health and contemplate whether something like cannabis is helpful or hurtful.”

Regardless of cancer history, the research revealed people reporting higher levels of pain were more likely to use cannabis, whereas women, older people, and those with higher incomes, medical insurance, or better mental health were less likely to be users.

The authors called for greater research into the health effects of cannabis use for cancer patients and survivors so doctors and patients can have more informed conversations about the risks and benefits.

“As with all health decisions, it’s best to talk to your doctor before making any big changes,” said study co-author Egidio Del Fabbro

“Now that marijuana is becoming legal in more parts of the [US], we’re expecting more questions, and although we may not have all the answers, we’re here to listen and provide our patients with the best available evidence.”