An adapted two-step floating catchment area method accounting for urban-rural differences in spatial access to pharmacies

Measuring Spatial Access of Vulnerable Population to HIV Testing Facilities in the Baton Rouge Metropolitan Statistical Area, Louisiana

Ensuring adequate and equitable access to affordable HIV testing is a crucial step toward ending the HIV epidemic (EHE). Using the high-burden Baton Rouge Metropolitan Statistical Area (MSA) as an example, we measure spatial access to HIV testing facilities for vulnerable populations and assess whether their access would improve if eliminating a considerable barrier-costs. Locations and status (free, low-cost, and full cost) of HIV testing facilities are searched on the Internet and confirmed through a field survey. Vulnerable populations include the uninsured and people living with HIV (PLWH), disaggregated from county-level HIV prevalence data. Spatial access is computed by a normalized urban-rural two-step floating catchment area (NUR2SFCA) method. Our survey confirms that only 11% and 37% of the 103 Internet-searched HIV testing facilities are indeed free and low-cost. Making more facilities cheaper or free increases the average access of PLWH, the uninsured, and the entire population but their geographic patterns vary. Free testing facilities, clustered in Baton Rouge city, are highly accessible to 82.6%, 69.4%, and 70.2% of three population groups living in East and West Baton Rouge Parish. In comparison, making all low-cost facilities free increases access in most outlying parishes but at the cost of reducing access in East Baton Rouge Parish, leaving west Livingston, north Iberville, and east Pointe Coupee Parish with the poorest access. Making all full-cost facilities cheaper or free exhibits a similar pattern. The study has important policy implications for where and how to improve access to HIV testing for vulnerable populations.

Access to community pharmacies based on drive time and by rurality across the contiguous United States

BACKGROUND

Considering that mail-order pharmacy use remains low in the United States, geographic accessibility of community pharmacies (pharmacy access) can have an outsized impact on a community's access to services and care, especially among rural residents. However, previous measurements of pharmacy access rely on methods that do not capture all aspects of geographic access.

OBJECTIVES

This study aimed to measure pharmacy access across the contiguous United States and by rural, suburban, and urban areas using drive-time analysis and an improved methodological approach.

METHODS

The 2-step floating catchment area method was used to measure pharmacy access by considering the supply capacity of pharmacies, population demand for pharmacies, and the interaction between them within a reasonable travel time range. This method is a methodologically improved approach compared with previous methods for measuring geographic access. Network analysis was used to measure drive time from the population-weighted centroids of census tracts to the geocoded location of community pharmacies. Census tract-level pharmacy access was measured using a 10- and 20-minute drive time. Census tracts were also categorized based on population per square mile as rural (< 1000), suburban (1000-3000), and urban (> 3000).

RESULTS

Across the contiguous United States, 79.9% and 91.1% of census tracts had access to at least 1 pharmacy per 10,000 people within a 10- and 20-minute drive time, respectively. Rural census tracts had the lowest share of access to at least 1 pharmacy per 10,000 people compared with suburban and urban tracts and for both drive times.

CONCLUSION

Community pharmacies are highly accessible health care access points, specifically in urban and suburban areas. Pharmacies should be considered to expand access to services with limited geographic accessibility such as treatment programs for opioid use disorders, primary care, and healthy foods.

Social Vulnerabilities and Spatial Access to Primary Healthcare through Car and Public Transportation System in the Albuquerque, NM, Metropolitan Area: Assessing Disparities through GIS and Multilevel Modeling

Primary healthcare (PHC) is a keystone component of population health. However, inequities in public transportation access hinder equitable usage of PHC services by minoritized populations. Using the multimodal enhanced 2-step floating catchment area method and data in 2018 and 2019 for spatial access to PHC providers (n = 1166) and social vulnerability markers through census block (n = 543) and tract data (n = 226), a generalized linear mixed-effect model (GLMEM) was constructed to test the effects of sociodemographic and community area correlates on both car and bus transit spatial access to PHC in the Albuquerque, New Mexico (NM) metropolitan area. Results for bus spatial access to PHC showed lower access for Hispanics (B =  - 0.097 ± 0.029 [- 0.154, - 0.040]) and non-Hispanic Whites (B =  - 0.106 ± 0.032 [- 0.169, - 0.043]) and a positive association between single-family households and bus spatial access (B = 1.573 ± 0.349 [0.866, 2.261]). Greater disability vulnerability (B =  - 0.569 ± 0.173 [- 0.919, - 0.259]) and language vulnerability (B =  - 0.569 ± 0.173 [- 0.919, - 0.259]) were associated with decreased bus spatial access. For car spatial access to PHC, greater SES vulnerability (B =  - 0.338 ± 0.021 [- 1.568, -0.143]), disability (B =  - 0.721 ± .092 [- 0.862, - 0.50 9]), and language vulnerability (B =  - 0.686 ± 0.172 [- 1.044, - 0.362]) were associated with less car spatial access. Results indicate a disproportionate burden of low PHC access among disadvantaged population groups who rely heavily on public transportation. These results necessitate targeted interventions to reduce these disparities in access to PHC.

Pharmacy deserts and patients with breast cancer receipt of influenza vaccines

BACKGROUND

Yearly influenza vaccination is strongly recommended at age 65 and reimbursed by Medicare without copays or deductibles at pharmacies and clinical settings. Uptake is low among patients with a high risk for influenza complications and good access to specialist care, such as recent cancer survivors. We hypothesized that more accessible pharmacies could be associated with higher immunization uptake in such patients.

OBJECTIVES

To determine whether pharmacy access is associated with influenza vaccination in subjects recently diagnosed with breast cancer, and whether this association differs by additional risk factors for influenza complications.

METHODS

We examined a cohort of patients with stage 0-III breast cancer diagnosed 2011-2015 from the Surveillance, Epidemiology, and End Results-Medicare cancer registry. All retail pharmacies in the United States were identified, and pharmacy access was measured by assessing supply and demand in each census tract using a 2-stage floating catchment area approach that accounted for pharmacy driving distances recommended by the Centers for Medicare and Medicaid Services. We examined the association of pharmacy access with influenza vaccination after breast cancer diagnosis in regression models.

RESULTS

More than 11% of 45,722 patients with breast cancer lived in census tracts where no pharmacies were within recommended driving distances from the population-weighted tract center. Vaccination in the year after diagnosis was less likely for patients in these very low-access tracts (adjusted odds ratio 0.92 [95% CI 0.86-0.96]), black (0.55 [0.51-0.60]) and Hispanic (0.76 [0.70-0.83]) women, and Medicaid recipients (0.74 [0.69-0.79]). Vaccination was inversely associated with per capita income in the subject's census tract, but there was no difference in the pharmacy effect by race, ethnicity, or census tract income.

CONCLUSION

Very low pharmacy access is associated with modest reductions in vaccination that could be useful for policy and planning regarding vaccinator resources and outreach.