Research ties dermatology workforce balance and melanoma outcomes
Phoenix — Findings from a study examining an association between dermatologist density and melanoma mortality suggest that better workforce distribution may lead to a population-level improvement in mortality related to this malignancy, reported researchers at the 2011 annual meeting of the Society for Investigative Dermatology.
"Using the data we collected to map dermatologist density nationwide shows a lack of dermatologists in the majority of counties but the presence of significant geographic disparity. The East and West Coast regions are fairly well saturated with dermatologists, while there appears to be a relative shortage throughout the center of the country," says Savina Aneja, B.A. "Based on the findings from our study, we would suggest that efforts to recruit dermatologists to areas that are currently underserved by the specialty, perhaps by creative incentives or tying residency positions or loan repayments to a contract of service, would be helpful for achieving a population-level reduction in melanoma mortality."
Ms. Aneja conducted the research as a third-year medical student at Case Western Reserve University School of Medicine, Cleveland, under the direction of Jeremy S. Bordeaux, M.D., M.P.H., assistant professor of dermatology, Case Western Reserve University School of Medicine, and director, melanoma program, University Hospitals of Cleveland.
Data for the study were extracted from the 2000 U.S. Census, Department of Health & Human Services Area Resource File, Centers for Disease Control and Prevention's National Vital Statistics System, the National Cancer Institute's Surveillance, Epidemiology and End Results, and the National Program for Cancer Registries.
Univariate analyses were performed to identify associations between a variety of possible predictor variables and melanoma mortality, and then independent predictors were investigated in a multivariate regression model.
Dermatologist density at the county level per 100,000 residents was calculated as a five-year mean for the period of 2002 to 2006, and the association with melanoma mortality was analyzed using cut-points of 0, >0 to 1, >1 to 2, >2 to 4, and >4 per 100,000. Using 0 dermatologists per 100,000 population as the reference group, the presence of >0 to 1 dermatologist per 100,000 people was associated with a statistically significant (35 percent) decrease in melanoma mortality, and there was a statistically significant (53 percent) reduction in areas where dermatologist density was >1 to 2.
The presence of >2 to 4 and >4 dermatologists per 100,000 population also significantly reduced melanoma mortality compared with having no dermatologists. However, the analyses showed a plateau effect such that the greatest reduction in mortality numerically was achieved in the category of >1 to 2 dermatologists per 100,000.
A previous study by Eide et al (Eide MJ, Weinstock MA, Clark MA. J Am Acad Dermatol. 2009;60(1):51-58), showing that higher dermatologist density was associated with a better prognosis for melanoma, defined by lower ratio of mortality:incidence, provided part of the motivation for undertaking the research, Ms. Aneja says.
"Recognizing that physician workforce can influence melanoma outcomes, we were interested in determining what density level made a difference in the rate of mortality," Ms. Aneja says.
The study by Eide et al also showed that increased family practitioner density was associated with worsening of melanoma prognosis, while internist density predicted better prognosis. The current study analyzed primary care physician density (internists, family care practitioners and pediatricians) as a predictive variable and found no association with melanoma mortality.
Classification as a health professional shortage area was also not associated with melanoma mortality, nor was age, education, income or unemployment rate. Variables that were significant predictors of reduced melanoma mortality were higher incidence of melanoma, greater proportion of Caucasians in the population, greater health insured populations, metropolitan county classification and presence of a hospital with an oncology department.
Ms. Aneja says that studies involving other specialties have also shown associations between provider density and healthcare outcomes as well as a plateau effect for density. For example, Odisho et al reported finding an association between urologist density and mortality rates for prostate, bladder and kidney cancer (Odisho AY, Cooperberg MR, Fradet V, et al. J Clin Oncol. 2010;28(15):2499-2504), but as in the melanoma study, increasing density above two urologists per 100,000 people did not further improve mortality outcomes for the urologic cancers.
"These findings suggest there may be a way to distribute specialists across the country to improve cancer outcomes," Ms. Aneja says.
The mechanism whereby increased dermatologist density contributes to reduced melanoma mortality is likely multifactorial. Earlier diagnosis, delivery of more appropriate treatment and improved education leading to better prevention as well as earlier diagnosis all probably play a role. "Our work is just a beginning to identifying possible strategies for reducing melanoma mortality. Studies determining how dermatologist density affects patient outcomes are worth pursuing," Ms. Aneja says.