Comparison of geographic methods to assess travel patterns of persons diagnosed with HIV in Philadelphia: how close is close enough?

Travel Burden and Timely Linkage to Care Among People Newly Diagnosed with HIV Infection in South Carolina from 2005 to 2020

This retrospective study explored the association between travel burden and timely linkage to care (LTC) among people with HIV (PWH) in South Carolina. HIV care data were derived from statewide all-payer electronic health records, and timely LTC was defined as having at least one viral load or CD4 count record within 90 days after HIV diagnosis before the year 2015 and 30 days after 2015. Travel burden was measured by average driving time (in minutes) to any healthcare facility visited within six months before and one month after the initial HIV diagnosis. Multivariable logistic regression models with the least absolute shrinkage and selection operator were employed. From 2005 to 2020, 81.2% (3,547 out of 4,366) of PWH had timely LTC. Persons who had longer driving time (adjusted Odds Ratio (aOR): 0.37, 95% CI: 0.14-0.99), were male versus female (aOR: 0.73, 95% CI: 0.58-0.91), had more comorbidities (aOR: 0.73, 95% CI: 0.57-0.94), and lived in counties with a higher percentage of unemployed labor force (aOR: 0.21, 95% CI: 0.06-0.71) were less likely to have timely LTC. However, compared to those aged between 18 and 24 years old, those aged between 45 and 59 (aOR:1.47, 95% CI: 1.14-1.90) or older than 60 (aOR:1.71, 95% CI: 1.14-2.56) were more likely to have timely LTC. Concentrated and sustained interventions targeting underserved communities and the associated travel burden among newly diagnosed PWH who are younger, male, and have more comorbidities are needed to improve LTC and reduce health disparities.

Urban-rural disparities in geographic accessibility to care for people living with HIV

In the United States, people living with HIV (PLWH) in rural areas fare worse along the HIV care continuum than their urban counterparts; this may be due in part to limited geographic access to care. We estimated drive time to care for PLWH, focusing on urban-rural differences. Adult Medicaid enrollees living with HIV and their usual care clinicians were identified using administrative claims data from 14 states (Medicaid Analytic eXtract, 2009-2012). We used geographic network analysis to calculate one-way drive time from the enrollee's ZIP code tabulation area centroid to their clinician's practice address, then examined urban-rural differences using bivariate statistics. Additional analyses included altering the definition of rurality; examining subsamples based on the state of residence, services received, and clinician specialty; and adjusting for individual and county characteristics. Across n = 49,596 PLWH, median drive time to care was 12.8 min (interquartile range 26.3). Median drive time for rural enrollees (43.6 (82.0)) was nearly four times longer than for urban enrollees (11.9 (20.6) minutes, p < 0.0001), and drive times exceeded one hour for 38% of rural enrollees (versus 12% of urban, p < 0.0001). Urban-rural disparities remained in all additional analyses. Sustained efforts to circumvent limited geographic access to care are critical for rural areas.

Effects of mode of transportation on PrEP persistence among urban men who have sex with men

Little is known about the effect of travel-related factors, such as mode of transportation, on retention in PrEP care, or PrEP persistence. We used data from the 2020 American Men's Internet Survey and conducted multilevel logistic regression to estimate the association between mode of transportation used for healthcare access and PrEP persistence among urban gay, bisexual, and other men who have sex with men (MSM) in the U.S. MSM using public transportation were less likely to report PrEP persistence (aOR: 0.51; 95% CI: 0.28-0.95) than MSM using private transportation. There were no significant associations between PrEP persistence and using active transportation (aOR: 0.67; 95% CI: 0.35-1.29) or multimodal transportation (aOR: 0.85; 95% CI: 0.51-1.43) compared to using private transportation. Transportation-related interventions and policies are needed to address structural barriers to accessing PrEP services and to improve PrEP persistence in urban areas.

Accessibility of HIV Services in Philadelphia: Location-Allocation Analysis

INTRODUCTION

As the first step in the HIV care continuum, timely diagnosis is central to reducing transmission of the virus and ending the HIV epidemic. Studies have shown that distance from a testing site is essential for ease of access to services and educational material. This study shows how location-allocation analysis can be used to improve allocation of HIV testing services utilizing existing publicly available data from 2015 to 2019 on HIV prevalence, testing site location, and factors related to HIV in Philadelphia, Pennsylvania.

METHODS

The ArcGIS Location-Allocation analytic tool was used to calculate locations for HIV testing sites using a method that minimizes the distance between demand-point locations and service facilities. ZIP code level demand was initially specified on the basis of the percentage of late HIV diagnoses and in a sensitivity analysis on the basis of a composite of multiple factors. Travel time and distance from demand to facilities determined the facility location allocation. This analysis was conducted from 2021 to 2022.

RESULTS

Compared with the 37 facilities located in 20 (43%) Philadelphia ZIP codes, the model proposed reallocating testing facilities to 37 (79%) ZIP codes using percent late diagnoses to define demand. On average, this would reduce distance to the facilities by 65% and travel time to the facilities by 56%. Results using the sensitivity analysis were similar.

CONCLUSIONS

A wider distribution of HIV testing services across the city of Philadelphia may reduce distance and travel time to facilities, improve accessibility of testing, and in turn increase the percentage of people with knowledge of their status.

Life With HIV in a Canadian Suburban Community: A Qualitative Inquiry of Health Care and Social Services Access

HIV has been examined in urban and rural contexts, but the suburban gradient has not been sufficiently described, despite the fact that many Canadians live in suburbia. Using qualitative description, we investigated how people living with HIV in a suburban community in Ontario, Canada, accessed health care and social services. Posters at the regional AIDS Service Organization and snowball sampling were used to recruit and interview 13 adult participants with various experiences and perspectives. A content analysis identified three meta-themes in the interviews: (a) transportation cost and time: barriers to access, (b) isolation, and (c) defective primary care: unmet and deflected needs. The findings have implications for the (a) development of community-based groups, (b) the role of transportation in health care and social services utilization, (c) community-based, interprofessional health and social care services, and (d) aging with HIV.

Presenting to the Emergency Department Versus Clinic-Based Sexually Transmitted Disease Care Locations for Testing for Chlamydia and Gonorrhea: A Spatial Exploration

BACKGROUND

Rates of sexually transmitted diseases (STDs) including chlamydia and gonorrhea are increasing in the United States while public health funding for STD services is decreasing. Individuals seek care in various locations including the emergency department (ED). The objective of this study is to investigate whether there are more physically proximal clinic-based STD care locations available to individuals who present to the ED in a major metropolitan area.

METHODS

Addresses of EDs, clinics, and patients 13 years or older in St. Louis City or County given a nucleic acid amplification test and assigned an STD diagnosis (n = 6100) were geocoded. R was used to analyze clinics within 5 radii from the patients' home address and assess missed clinic opportunities (open, no charge, with walk-in availability) for those living in an urban versus suburban area.

RESULTS

In urban areas, 99.1% of individuals lived closer to a clinic than the ED where they sought STD services; in suburban areas, 82.2% lived closer to a clinic than the ED where they presented. In the region, 50.6% lived closer to the health department-based STD care location than the hospital where they presented. Up to a third of ED patient visits for STD care could have occurred at a clinic that was closer to the patient's home address, open, no charge, and available for walk-in appointments.

CONCLUSIONS

Clinic availability is present for most of the individuals in our study. Clinics providing STD services can increase advertising efforts to increase public awareness of the services which they provide.

Analysis of spatial equity and access to urban parks in Ilam, Iran

Adequate number of parks and amount of land allocated to those parks, to provide equal access for all city residences, are important factors in achieving cities to spatial equity. The purpose of this study was to analyze availability, distribution and accessibility of urban parks in the city of Ilam, Iran. In this research, descriptive statistics and buffering techniques in GIS were used. Our findings show that in Ilam, the indexes of park coverage and per capita park area are 2.13% and 1.91 m² respectively, that are much lower than those of Iranian standards. Only slightly over a third of Ilam residents live within 200 m of a park. Parks are disproportionately agglomerated in the northern half of the city. Whilst 30.4% of the city's surface area, where 27.3% of the city's population reside, is not covered by park service areas, some other parts benefit from 13 park service areas. The index of per capita access to parks for 34.8% of Ilam population that reside in 32.7% of Ilam surface area, is less than 1.5 m². The city in general suffers from a shortage of parks, but this, in particular, is severe in the city center and in the southern parts, highlighting the need for allocation of more lands for park provision.

Structural barriers to comprehensive, coordinated HIV care: geographic accessibility in the US South

Structural barriers to HIV care are particularly challenging in the US South, which has higher HIV diagnosis rates, poverty, uninsurance, HIV stigma, and rurality, and fewer comprehensive public health programs versus other US regions. Focusing on one structural barrier, we examined geographic accessibility to comprehensive, coordinated HIV care (HIVCCC) in the US South. We integrated publicly available data to study travel time to HIVCCC in 16 Southern states and District of Columbia. We geocoded HIVCCC service locations and estimated drive time between the population-weighted county centroid and closest HIVCCC facility. We evaluated drive time in aggregate, and by county-level HIV prevalence quintile, urbanicity, and race/ethnicity. Optimal drive time was ≤30 min, a common primary care accessibility threshold. We identified 228 service locations providing HIVCCC across 1422 Southern counties, with median drive time to care of 70 min (IQR 64 min). For 368 counties in the top HIV prevalence quintile, median drive time is 50 min (IQR 61 min), exceeding 60 min in over one-third of these counties. Among counties in the top HIV prevalence quintile, drive time to care is six-folder higher for rural versus super-urban counties. Counties in the top HIV prevalence quintiles for non-Hispanic Blacks and for Hispanics have >50% longer drive time to care versus for non-Hispanic Whites. Including another potential care source-publicly-funded health centers serving low-income populations-could double the number of high-HIV burden counties with drive time ≤30 min, representing nearly 35,000 additional people living with HIV with accessible HIVCCC. Geographic accessibility to HIVCCC is inadequate in the US South, even in high HIV burden areas, and geographic and racial/ethnic disparities exist. Structural factors, such as geographic accessibility to care, may drive disparities in health outcomes. Further research on programmatic policies, and evidence-based alternative HIV care delivery models improving access to care, is critical.

The approaches to measuring the potential spatial access to urban health services revisited: distance types and aggregation-error issues

BACKGROUND

The potential spatial access to urban health services is an important issue in health geography, spatial epidemiology and public health. Computing geographical accessibility measures for residential areas (e.g. census tracts) depends on a type of distance, a method of aggregation, and a measure of accessibility. The aim of this paper is to compare discrepancies in results for the geographical accessibility of health services computed using six distance types (Euclidean and Manhattan distances; shortest network time on foot, by bicycle, by public transit, and by car), four aggregation methods, and fourteen accessibility measures.

METHODS

To explore variations in results according to the six types of distance and the aggregation methods, correlation analyses are performed. To measure how the assessment of potential spatial access varies according to three parameters (type of distance, aggregation method, and accessibility measure), sensitivity analysis (SA) and uncertainty analysis (UA) are conducted.

RESULTS

First, independently of the type of distance used except for shortest network time by public transit, the results are globally similar (correlation >0.90). However, important local variations in correlation between Cartesian and the four shortest network time distances are observed, notably in suburban areas where Cartesian distances are less precise. Second, the choice of the aggregation method is also important: compared with the most accurate aggregation method, accessibility measures computed from census tract centroids, though not inaccurate, yield important measurement errors for 10% of census tracts. Third, the SA results show that the evaluation of potential geographic access may vary a great deal depending on the accessibility measure and, to a lesser degree, the type of distance and aggregation method. Fourth, the UA results clearly indicate areas of strong uncertainty in suburban areas, whereas central neighbourhoods show lower levels of uncertainty.

CONCLUSION

In order to accurately assess potential geographic access to health services in urban areas, it is particularly important to choose a precise type of distance and aggregation method. Then, depending on the research objectives, the choices of the type of network distance (according to the mode of transportation) and of a number of accessibility measures should be carefully considered and adequately justified.

Distance to testing sites and its association with timing of HIV diagnosis

Early HIV diagnosis enables prompt treatment initiation, thereby contributing to decreased morbidity, mortality, and transmission. We aimed to describe the association between distance from residence to testing sites and HIV disease stage at diagnosis. Using HIV surveillance data, we identified all new HIV diagnoses made at publicly funded testing sites in central North Carolina during 2005-2013. Early-stage HIV was defined as acute HIV (antibody-negative test with a positive HIV RNA) or recent HIV (normalized optical density <0.8 on the BED assay for non-AIDS cases); remaining diagnoses were considered post-early-stage HIV. Street distance between residence at diagnosis and (1) the closest testing site and (2) the diagnosis site was dichotomized at 5 miles. We fit log-binomial models using generalized estimating equations to estimate prevalence ratios (PR) and robust 95% confidence intervals (CI) for post-early-stage diagnoses by distance. Models were adjusted for race/ethnicity and testing period. Most of the 3028 new diagnoses were black (N = 2144; 70.8%), men who have sex with men (N = 1685; 55.7%), and post-early-stage HIV diagnoses (N = 2010; 66.4%). Overall, 1145 (37.8%) cases traveled <5 miles for a diagnosis. Among cases traveling ≥5 miles for a diagnosis, 1273 (67.6%) lived <5 miles from a different site. Residing ≥5 miles from a testing site was not associated with post-early-stage HIV (adjusted PR, 95% CI: 0.98, 0.92-1.04), but traveling ≥5 miles for a diagnosis was associated with higher post-early HIV prevalence (1.07, 1.02-1.13). Most of the elevated prevalence observed in cases traveling ≥5 miles for a diagnosis occurred among those living <5 miles from a different site (1.09, 1.03-1.16). Modest increases in post-early-stage HIV diagnosis were apparent among persons living near a site, but choosing to travel longer distances to test. Understanding reasons for increased travel distances could improve accessibility and acceptability of HIV services and increase early diagnosis rates.