The surprising reasons why wealthier people are more likely to survive melanoma

Money may not buy you happiness, but having more of it may be able to buy you a better prognosis if you’re diagnosed with skin cancer, according to a recent study.

We already know that poverty is a risk factor for poor health and premature mortality, according to a 2004 meta-analysis of income inequality and health in the journal Epidemiologic Reviews. But a new skin cancer study finds that wealthier people actually have a higher chance of being diagnosed with melanoma—as well as a higher chance of surviving it.

The study of 1,339 melanoma patients at New York University Langone Medical Center compared outcomes for people with incomes above and below a median income of $90,000 per year. Patients on the low end of the group’s income spectrum were significantly more likely to have a shorter overall survival rate, post-recurrence survival rate, and to have more advanced stages of cancer.

“On a dollar by dollar basis, the more money you make per year, the better your outcome is for melanoma,” says Dr. Jennifer Stein, one of the study’s authors and an associate professor at New York University medical school’s dermatology department. A practicing dermatologist, Stein specializes in treating people at high risk for melanoma.

There are several possible reasons for the income disparities found in the study. People with lower incomes seem to get diagnosed later than wealthier people, which could be a factor in recurrence rates. Another factor is that people with a higher household income tend to get a thinner and less deadly kind of cancer than the nodular melanomas more common among those who earn less. (More research is needed as to why this might be.)

Meanwhile, the higher melanoma rate for wealthier people is often attributed to the fact that they have more opportunity to vacation in the French Riviera, Bora Bora, and other places where they can catch some “recreational sunlight,” as the authors put it.

It’s also possible that lower-income households have less awareness of melanoma, which may make them less likely to get checked out. In other cases, lack of health care access could be a factor. But that did not play much of a role in this particular study, since the majority of NYU patients are insured, the researchers wrote.

While the study offers some intriguing results, there’s still a lot we don’t know about who is most vulnerable to skin cancer. Another recent study on melanoma looked at 566 subjects within three months of a melanoma diagnosis. It found that most of the patients had few moles (between 0 and 20) and no “atypical moles” at all. (Atypical moles tend to be large and have irregular borders, multiple colors or a changing shape, but are actually benign.) The study, published in JAMA Dermatology in March, says the findings indicate that people do not automatically need a skin exam just because they have a lot of moles.

This finding may seem counterintuitive. After all, the Skin Cancer Foundation says that having a lot of moles could put people at risk for melanoma, and dermatologists and skin cancer advocacy groups have long urged us to be on the lookout for atypical moles.

But Stein sees the study’s results should not stop people from paying extra attention to moles, especially those that look unusual. “Being moley and having atypical moles are still risk factors for having melanoma,” she says. “But there’s more to it.” Others who are at risk of developing skin cancer include redheads, people with a history of sunburns or tanning bed use, and men over 50—regardless of whether they have moles, she said.

Indeed, the JAMA Dermatology study’s overall findings changed when it looked only at patients younger than 60. Among this younger demographic, researchers found that atypical moles are worth watching out for–and are more likely to be found on patients who have a lot of moles generally.

“What this study showed is that atypical moles are more important than just the total amount of moles,” said Stein. “We can’t only focus on moley patients because then you’d miss these patients who aren’t moley at all and still wind up with melanoma.”

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