Melanoma mortality rate 5 times higher in developed countries

When researchers studied mortality from conditions with skin manifestations in developed versus developing countries, they found living in the developed world doesn’t always translate to lower death rates. Age-adjusted mortality for melanoma, for example, was about five times greater in the developed world than in developing countries.

On the other end of the spectrum, measles’ mortality was nearly 200 times higher in the developing world.

Robert Dellavalle, M.D., Ph.D., M.S.P.H., the paper’s senior author and associate professor of dermatology at the University of Colorado School of Medicine, Aurora, Colorado, says he and colleagues analyzed 1990 to 2010 data from the Global Burden of Disease project. The project is funded by the Bill and Melinda Gates Foundation and includes 1 billion data points on 269 diseases.

They focused on conditions that have skin manifestations and mortality in the developed world versus the developing world, including malignant melanoma; basal and squamous cell cancers; bacterial skin diseases; decubitus ulcer; cellulitis; varicella, including chickenpox, congenital varicella infection and herpes zoster; syphilis; measles; and dengue.

Researchers found the greatest differences among death rates for melanoma, measles and syphilis.

• “Melanoma death rates were 5.6 times and 4.7 times greater in developed compared with developing countries in 1990 and 2010, respectively,” according to the paper.

• Measles death rates, though much higher in developing countries, improved. In 1990, death from measles was 345 higher in developing countries. By 2010, it was 197 times greater.

• Syphilis death rates went from 33 times greater in 1990 to 45 times higher in the developing world in 2010.

• Dengue fever and dengue hemorrhagic fever had higher age-adjusted mortality in the developing versus the developed world.

• Nonmelanoma skin cancer deaths were slightly higher in developed countries.

“We’re talking about mortality … normally these skin cancers don’t cause people to die,” Dr. Dellavalle says. “We did not see a tremendous difference (in nonmelanoma mortality) between developed and developing countries. The main age-adjusted mortality … for nonmelanoma skin cancers was about 0.5 (in developed countries) to 0.4 (in developing countries). Not a significant one. It’s primarily squamous cell that we’re talking about.”

Next: What about Ebola virus?

What about Ebola?

Ebola wasn’t a factor in the data period, so the researchers sent a subsequent letter to the Journal of the American Academy of Dermatology, where their research was published online Oct. 2, stating that Ebola could change the study’s results. At the time of writing, 4,447 people had died of Ebola in developing countries compared with two in developed countries.

“… It’s a fast-moving, very deadly disease with skin manifestations that really weren’t a part of the study between the years of 1990 and 2010,” Dr. Dellavalle tells Dermatology Times. “In looking at the issue, we also noted that there are very few pictures of Ebola in the literature, in terms of the skin rash it causes. So we called out for more pictures being introduced as soon as possible.”

The late-breaking addendum to the paper suggests that Ebola’s skin manifestations have been under-reported. According to the authors, “non-proritic morbilliform eruptions” may occur within two to seven days of symptom onset. Recognizing this could help early detection of the disease, they wrote.

The researchers also suggest campaigns to eradicate measles in sub-Saharan Africa are effective but need continued improvement, and a treatment for syphilis remains a major health challenge in the developing world.

As for the higher melanoma incidence in developed countries, Dr. Dellavalle says it comes down to sun exposure and the ways in which light-skinned populations in countries such as the United States embrace tanning.

Sources:

Interview with Dr. Dellavalle and this paper: Boyers LN, Karimkhani C, Naghavi M, et al. Global mortality from conditions with skin manifestations. J Am Acad Dermatol. 2014 Oct 2. pii: S0190-9622(14)01869-6.