SKIN May 2023 Volume 7 Issue 3 (c) 2023 THE AUTHORS. Published by the National Society for Cutaneous Medicine. 811 BRIEF ARTICLE Five Years Later: Continuing Disparity in the Geographic Density and Distribution of U.S. Dermatologists Christopher N. Nguyen, MD1, Quoc-Bao Nguyen, MD, MBA2,3, Kyle Lauck, MD4, Adelaide Hebert, MD2,3 1Department of Internal Medicine, Northside Hospital Gwinnett, Lawrenceville, GA 2Department of Dermatology, The University of Texas MD Anderson Cancer Center, Houston, TX 3Department of Dermatology, UTHealth McGovern Medical School, Houston, TX 4Department of Internal Medicine, UTHealth McGovern Medical School, Houston, TX Despite expansion of the dermatologic workforce, a discrepancy remains in the geographical distribution of dermatologists across the United States (US). From a 2014 American Academy of Dermatology (AAD) survey, dermatologists in rural areas were more likely to report an undersupply of dermatologists, while dermatologists in urban areas were more likely to report an oversupply.1 The Glazer et al. studies analyzing the geographic distribution of practicing dermatologists in the US in 2009 and 2016 confirmed this maldistribution.2,3 This study presents a continuation of those studies and aims to reexamine the current geographical density of dermatologists to describe any changes that may have occurred over the past 5 and 12 years, respectively. ABSTRACT Objectives: A discrepancy exists in the geographical distribution of dermatologists across the United States (US). The aim of this study was to reexamine the current geographical density of dermatologists to describe any changes compared to date from 5 and 12 years ago. Methods: Membership data from the 2021 American Academy of Dermatology (AAD) database were retrieved to characterize the distribution of dermatologists in 3-digit zip code areas. Results: Out of 712 populated zip codes with dermatologists, 510 (71.6%) had less than 4 dermatologists per 100,000, as compared to 515 (72.3%) in 2016 (– 0.19% CAGR). The dermatologist density of the 100 most populated areas (M = 4.5 dermatologists per 100,000, SD = 3.3) and 100 least populated areas (M = 1.6 dermatologists per 100,000, SD = 6.2) were significantly different (P < 0.0001). Conclusion: This analysis provides continued trends to compare to previous studies performed in 2016 and 2009. The highest and lowest density areas were similar to results from previous studies. The results indicate an enduring and significant maldistribution of dermatologists in the US. INTRODUCTION METHODS SKIN May 2023 Volume 7 Issue 3 (c) 2023 THE AUTHORS. Published by the National Society for Cutaneous Medicine. 812 Like the previous studies, de-identified data for AAD members were retrieved from the most current AAD membership database, the 2021 AAD membership database for this analysis. Demographic information included the member’s category, state, and zip code. Fellows were included as practicing dermatologists. US territories were excluded from this analysis. US population data was obtained from the American Community Survey. Information associated with 5-digit zip codes were consolidated to their corresponding larger 3-digit zip codes. Compound annual growth rates (CAGR) were calculated to assess annual percentage growth. And descriptive statistics and unpaired two-sample t-tests were used. Institutional review board approval was not necessary as no human subjects were used for this study. The 2021 database contained 11,525 dermatologists compared with 10,845 in 2016 (1.22% CAGR) and 9,598 in 2009 (1.54% CAGR). With the U.S. population approaching 328 million, there are 3.5 dermatologists per 100,000 people, an increase from 3.4 in 2016 (0.58% CAGR) and 3.2 in 2009 (0.75% CAGR). There were 712 zip codes that were populated and had at least 1 dermatologist; 510 (71.6%) of them had less than 4 dermatologists per 100,000, as compared to 515 (72.3%) in 2016 (– 0.19% CAGR). There were 174 areas that were populated (average population of 99,000) but had no dermatologists at all. The dermatologist density of the 100 most populated areas (M = 4.5 dermatologists per 100,000, SD = 3.3) and 100 least populated areas (M = 1.6 dermatologists per 100,000, SD = 6.2) were significantly different (P < 0.0001). The 10 highest and lowest dermatologist density locations from the current analysis and the 2016 analysis are listed (Figure 1 and Figure 2). This listing is based on locations that have at least 1 dermatologist. The average density for the 10 densest locations was 24.6 dermatologists per 100,000, an increase from 23.3 in 2016 (1.1% CAGR), but a decrease from 25 in 2009 (– 0.13% CAGR). And 83.5% of the dermatologists in the top 10 areas practice in the northeast. Specifically, 93% can be found in either Manhattan or Boston. Currently, 36.5% of dermatologists practice in the 100 densest areas, a downtrend from 38.6% in 2016 (– 1.11% CAGR) and 40% in 2009 (– 0.76% CAGR). Conversely, only 1.6% of dermatologists practice in the 100 least dense areas as compared to 1.8% in 2016 (– 2.33% CAGR). Our analysis reveals an enduring maldistribution of dermatologists between urban and rural areas (Figure 3). Almost 20% of populated zip codes did not have a single dermatologist. Like in 2009, the 10 densest zip codes had an average density 7 times the national average. Also, 9 of the 10 densest zip codes in 2016 remained among the top 10 in 2021. None of the least dense areas in 2016 improved to more than 1 dermatologist per 100,000. Some suggest that 4 dermatologists per 100,000 people is the ratio needed to sufficiently care for a population.3 Consistent with 2016, over 70% of areas do not meet that target density and nearly 60% have less than 3 per 100,000. In the past 5 years, only 5 more zip codes reached this threshold. These results may indicate that initiatives aimed at redistribution of dermatologists have not made a major difference. RESULTS DISCUSSION SKIN May 2023 Volume 7 Issue 3 (c) 2023 THE AUTHORS. Published by the National Society for Cutaneous Medicine. 813 Figure 1. Comparison of the 10 most dermatologist-dense areas, for locations with at least 1 dermatologist, in the United States in 2021 vs 2016. SKIN May 2023 Volume 7 Issue 3 (c) 2023 THE AUTHORS. Published by the National Society for Cutaneous Medicine. 814 Figure 2. Comparison of the 10 least dermatologist-dense areas, for locations with at least 1 dermatologist, in the United States in 2021 vs 2016. SKIN May 2023 Volume 7 Issue 3 (c) 2023 THE AUTHORS. Published by the National Society for Cutaneous Medicine. 815 Figure 3. US Dermatologist Density by 3-Digit Zip Code. The number of dermatologists practicing per 100,000 people in each 3-digit zip code is indicated by the colors on the map. Zip codes without any dermatologists are included in white. Addressing underserved areas remains paramount as dermatologist density is associated with patient outcomes, particularly in melanoma and Merkel cell carcinoma.4,5 Multiple solutions have been considered. One of the strongest barriers in rural physician retention is lack of geographical connection, partly due to the limited residency positions available. Partnerships between residency programs and rural hospitals may expand residency spots, while also supporting underserved areas.6 Advanced practice practitioners may alleviate rural areas, however, they tend to favor urban areas as well.7 And teledermatology has proven to be effective in rural communities, with reimbursement constraints as the greatest barrier.8 Other strategies to consider include financial incentives, increasing physician spouse job opportunities, and recruiting students of rural backgrounds. This study is limited by the AAD membership database, as AAD membership distribution may not represent the true distribution of all US dermatologists. However, this analysis may still add to the overall discussion and provide insight into the subject, since we used a consistent methodology as previous studies and present trends over a 5- and 12- year span. Another limitation is our analysis assumes each area requires similar a dermatologist density (4 dermatologists per SKIN May 2023 Volume 7 Issue 3 (c) 2023 THE AUTHORS. Published by the National Society for Cutaneous Medicine. 816 100,000 people) and we cannot account for specific differences in demand within each area. The data presented constitutes one metric and should be interpreted alongside other measures of adequacy (such as appointment wait-times) for a holistic viewpoint of this nuanced issue. Based on the AAD membership database, an enduring maldistribution of dermatologists exists. This complex issue likely needs a multifaceted solution with continual effort and thought from leaders in the field. Recurrent assessment of the database in the future can continue to help identify areas that may be underserved. This knowledge may provide insight into the effectiveness and implementation of countermeasures and, ultimately, improve patient care and outcomes. Conflict of Interest Disclosures: None Funding: None Corresponding Author: Christopher N. Nguyen, MD 1 Baylor Plaza Houston, TX 77030 Email: christopher.nguyen42@gmail.com References: 1. Ehrlich A, Kostecki J, Olkaba H. Trends in dermatology practices and the implications for the workforce. J Am Acad Dermatol. 2017;77(4):746-752. doi:10.1016/j.jaad.2017.06.030 2. Yoo JY, Rigel DS. Trends in dermatology: geographic density of US dermatologists. Arch Dermatol. 2010;146(7):779. doi:10.1001/archdermatol.2010.127 3. Glazer AM, Farberg AS, Winkelmann RR, et al. Analysis of Trends in Geographic Distribution and Density of US Dermatologists. JAMA Dermatol. 2017;153(4):322-325. doi:10.1001/jamadermatol.2016.5411 4. Aneja S, Aneja S, Bordeaux JS. Association of increased dermatologist density with lower melanoma mortality. Arch Dermatol. 2012;148(2):174-178. doi:10.1001/archdermatol.2011.345 5. Criscito MC, Martires KJ, Stein JA. A population- based cohort study on the association of dermatologist density and Merkel cell carcinoma survival. J Am Acad Dermatol. 2017;76(3):570- 572. doi:10.1016/j.jaad.2016.10.043 6. Feng H, Berk-Krauss J, Feng PW, et al. Comparison of Dermatologist Density Between Urban and Rural Counties in the United States. JAMA Dermatol. 2018;154(11):1265–1271. doi:10.1001/jamadermatol.2018.3022 7. Coustasse A, Sarkar R, Abodunde B, et al. Use of Teledermatology to Improve Dermatological Access in Rural Areas. Telemed J E Health. 2019;25(11):1022-1032. doi:10.1089/tmj.2018.0130. Epub 2019 Feb 11. PMID: 30741608. 8. Adamson AS, Suarez EA, McDaniel P, Leiphart PA, Zeitany A, Kirby JS. Geographic Distribution of Nonphysician Clinicians Who Independently Billed Medicare for Common Dermatologic Services in 2014. JAMA Dermatol. 2018;154(1):30-36. doi:10.1001/jamadermatol.2017.5039 CONCLUSION