Access Denied: Unpacking Pharmacy and Food Deserts in Harris County, Texas

In regions characterized by limited access to pharmacies-commonly referred to as pharmacy deserts-medication adherence tends to be lower, particularly among underserved and vulnerable populations. Similarly, food deserts denote areas with constrained access to nutritious food options, thereby exacerbating food and nutrition insecurity. While both heavily influence health outcomes, a paucity of literature explores the intersection between pharmacy deserts and food deserts.

We combined two data sets: (a) community/retail pharmacy brand and location data, and (b) the Food Access data set. A scatterplot was created using the transformed values of pharmacies per 1,000 population and Food Access as the x and y coordinates, respectively. The scatterplot was divided into nine parts based on the 33rd and 67th percentile values of both variables, categorized as a combination of low, median, and high pharmacy and food access. For further analysis, we categorized zip codes with limited access by median income ratio, poverty level, and diversity.

Overall, approximately one-third of all zip codes exhibited low pharmacy access, and another third demonstrated low food access. About 20% of zip codes experienced both low pharmacy and low food access. As the pharmacy access increased, food access also increased, suggesting that zip codes with greater pharmacy access tend to have disproportionately higher food access, consistent with an exponential-type relationship. Low pharmacy and food access were predominantly in zip codes with higher poverty rates and diversity.

Limited access to both pharmacies and nutritious food options places an added burden on vulnerable populations, contributing to challenges in managing chronic diseases and maintaining overall health. This limited accessibility highlights the need for targeted interventions that address these dual resource shortages.