Investigation of disparities in geographic accessibility to emergency stroke and myocardial infarction care in East tennessee using geographic information systems and network analysis

Accessibility evaluation and multi-scenario optimization of medical services in underdeveloped city driven by multi-source data and latest policies for China

Equitable and high-quality medical services are more urgent in underdeveloped cities for the higher population ageing and demanding social justice. However, there is little attention paid to the multi-level medical services, particularly regarding the time indicators under the latest policies for underdeveloped cities. The improved efforts were hampered partly by single scenario of location optimization, ignoring the integrated optimization for both road infrastructure and institution location. Toward the healthy China 2030 and rural revitalization policy, this study systematically investigated medical services for underdeveloped cities by constructing a multi-level evaluation and multi-scenario optimization framework with Geographical Information System technology in a case study of Xuchang City in China. Following the time goals from the latest policies, the services of high-quality hospitals and primary health centers were multi-level evaluated by network analysis method and further optimized through multi-scenario involving different new multi-level medical facilities and roads. Driven by urban-rural inequalities, candidate facilities were first selected based on multi-source data and then determined by location‑allocation analysis method, while new roads were assumed by space syntax method. The improvement rose rapidly and finally slowly with the increasing number of candidates. Few new roads and facilities could be more suitable, and the priority was explored under the local economy and planning. The findings could provide valuable support for urban healthy development under the latest policies.

Prehospital stroke care in Singapore

ABSTRACT

Due to the narrow window of opportunity for stroke therapeutics to be employed, effectiveness of stroke care systems is predicated on the efficiency of prehospital stroke systems. A robust prehospital stroke system of care that provides a rapid and well-coordinated response maximises favourable poststroke outcomes, but achieving this presents a unique set of challenges dependent on demographic and geographical circumstances. Set in the context of a highly urbanised first-world nation with a rising burden of stroke, Singapore's prehospital stroke system has evolved to reflect the environment in which it operates. This review aims to characterise the current state of prehospital stroke care in Singapore, covering prehospital aspects of the stroke survival chain from symptom onset till arrival at the emergency department. We identify areas for improvement and innovation, as well as provide insights into the possible future of prehospital stroke care in Singapore.

Identifying the vulnerable regions of emergency medical services based on the three-stage of accessibility: a case study in Xi'an, China

Background

Emergency department crowding is an obstacle in the process of obtaining emergency care services, which will lead to the increase of time cost. Most studies focused on the direct access to emergency medical resources, and few studies took the crowding of hospital emergency department as an evaluation index to reflect the convenience of obtaining emergency medical resources. It is a significance for the identification of areas with insufficient access to emergency service resources with this method.

Methods

This paper utilizes the improved potential model and the inverted Two-Step Floating Catchment Area method, combined with network map API service data to evaluate response time, delivery time and waiting time (for emergency department crowding) spent in different residential areas of Xi’an City in the process of emergency. Meanwhile, the vulnerable regions of gaining emergency medical resources are identified through the comprehensive analysis of the three stages of emergency.

Results

The studies show that the residents in built-up area are more convenient to get ambulance service and arrive at care hospitals than those in suburban areas, but they may face greater hospital crowdedness. Although suburban residents are faced with low hospital crowdedness, they spend more time on getting ambulances and going to care hospitals. The accessibility of emergency medical resources varies greatly among residents in different regions, with 5.38% of the residents were identified in the high-risk area distributing in suburban residential areas in the south of the city center, 21.92% in the medium risk area in the southern mountainous areas and the periphery of the core suburban areas of the city, and 46.11% in the low-risk area which are mainly distributed in built-up areas in gaining emergency medical services.

Conclusions

Obviously, getting an ambulance and arriving at the nearest hospital quickly shows that it is conducive to access to emergency resources. However, the impact of hospital emergency crowding can not be ignored, especially in the area surrounded by high-grade hospitals in the central area of the city. In considering the spatial layout of emergency stations and emergency hospitals, the dislocation distribution of hospitals at different levels should be reasonably adjusted to balance the equity of residents in obtaining emergency medical resources.

Concept review of regionalized systems of acute care: Is regionalization the next frontier in sepsis care?

Regionalization has become a buzzword in US health care policy. Regionalization, however, has varied meanings, and definitions have lacked contextual information important to understanding its role in improving care. This concept review is a comprehensive primer and summation of 8 common core components of the national models of regionalization informed by text-based analysis of the writing of involved organizations (professional, regulatory, and research) guided by semistructured interviews with organizational leaders. Further, this generalized model of regionalized care is applied to sepsis care, a novel discussion, drawing on existing small-scale applications. This discussion highlights the fit of regionalization principles to the sepsis care model and the actualized and perceived potential benefits. The principal aim of this concept review is to outline regionalization in the United States and provide a roadmap and novel discussion of regionalized care integration for sepsis care.

Assessing Trauma Center Accessibility for Healthcare Equity Using an Anti-Covering Approach

Motor vehicle accidents are one of the most prevalent causes of traumatic injury in patients needing transport to a trauma center. Arrival at a trauma center within an hour of the accident increases a patient's chances of survival and recovery. However, not all vehicle accidents in Tennessee are accessible to a trauma center within an hour by ground transportation. This study uses the anti-covering location problem (ACLP) to assess the current placement of trauma centers and explore optimal placements based on the population distribution and spatial pattern of motor vehicle accidents in 2015 through 2019 in Tennessee. The ACLP models seek to offer a method of exploring feasible scenarios for locating trauma centers that intend to provide accessibility to patients in underserved areas who suffer trauma as a result of vehicle accidents. The proposed ACLP approach also seeks to adjust the locations of trauma centers to reduce areas with excessive service coverage while improving coverage for less accessible areas of demand. In this study, three models are prescribed for finding optimal locations for trauma centers: (a) TraCt: ACLP model with a geometric approach and weighted models of population, fatalities, and spatial fatality clusters of vehicle accidents; (b) TraCt-ESC: an extended ACLP model mitigating excessive service supply among trauma center candidates, while expanding services to less served areas for more beneficiaries using fewer facilities; and (c) TraCt-ESCr: another extended ACLP model exploring the optimal location of additional trauma centers.

Impact of travel time uncertainties on modeling of spatial accessibility: a comparison of street data sources

GIS-based spatial access measures have been used extensively to monitor social equity and to help develop policy. However, inherent uncertainties in the road datasets used in spatial access estimates remain largely underreported. These uncertainties might result in unrecognized biases within visualization products and decision-making outcomes that strive to improve social equity based on seemingly egalitarian accessibility metrics. To better understand and address these uncertainties, we evaluated variations in travel impedance for car and bus transportation using proprietary, volunteer-information-based, and free (non-volunteer-information-based) street networks. We then interpreted the measured variations through the lens of street data uncertainty and its propagation in a common E2SFCA model of spatial accessibility. Results indicated that travel impedance disagreement propagates through the modeling process to effect agreement of spatial access index (SPAI) estimates among different street sources, with larger uncertainties observed for bus travel than car travel. Higher impedance coefficients (β), a model parameter, reduced the impact of street-source variations on estimates. Less urbanized regions were found to experience higher street-source variations when compared with the core-metropolitan area. We also demonstrated that a relative spatial access measure - the spatial access ratio (SPAR) - reduced uncertainties introduced by the choice of street datasets. Careful selection of reliable street sources and model parameters (e.g., higher β), as well as consideration of the potential for bias, particularly for less urbanized areas and areas reliant on public transportation, is warranted when leveraging SPAI to inform policy. When reliable/accurate road network data is not accessible or data quality information is not available, the SPAR is a suitable alternative or supplement to SPAI for visualization and analyses.

Exploring Access to Independent Living Services for People With Disabilities Through a Transportation Network Analysis

Centers for Independent Living (CILs) are nonresidential, nonprofit agencies that provide independent living services to people with disabilities across the nation. The services CILs provide are invaluable to people with disabilities living independently in the community. Accessing CIL services can be challenging for people with disabilities, particularly for individuals in rural areas. A geographic analysis called a transportation network analysis is one method for assessing access to CIL services. We draw on the distribution of CILs across the country and in two rural states (Montana and Arkansas) to assess levels of geographic access using travel distance along national and local road networks. Incorporating data from the American Community Survey allowed us to estimate the number of people with disabilities living within certain distance thresholds from CILs. We saw increased access in urban areas where there is a higher concentration of CILs, suggesting that people with disabilities in rural areas have limited access to CIL services. We explore how partnering with Area Agencies on Aging has the potential to expand access to services for people with disabilities in rural areas, highlighting the utility of geographic analysis in social service provision.

Wildfire Smoke Is Associated With an Increased Risk of Cardiorespiratory Emergency Department Visits in Alaska

Alaskan wildfires have major ecological, social, and economic consequences, but associated health impacts remain unexplored. We estimated cardiorespiratory morbidity associated with wildfire smoke (WFS) fine particulate matter with a diameter less than 2.5 μm (PM2.5) in three major population centers (Anchorage, Fairbanks, and the Matanuska-Susitna Valley) during the 2015-2019 wildfire seasons. To estimate WFS PM2.5, we utilized data from ground-based monitors and satellite-based smoke plume estimates. We implemented time-stratified case-crossover analyses with single and distributed lag models to estimate the effect of WFS PM2.5 on cardiorespiratory emergency department (ED) visits. On the day of exposure to WFS PM2.5, there was an increased odds of asthma-related ED visits among 15-65 year olds (OR = 1.12, 95% CI = 1.08, 1.16), people >65 years (OR = 1.15, 95% CI = 1.01, 1.31), among Alaska Native people (OR = 1.16, 95% CI = 1.09, 1.23), and in Anchorage (OR = 1.10, 95% CI = 1.05, 1.15) and Fairbanks (OR = 1.12, 95% CI = 1.07, 1.17). There was an increased risk of heart failure related ED visits for Alaska Native people (Lag Day 5 OR = 1.13, 95% CI = 1.02, 1.25). We found evidence that rural populations may delay seeking care. As the frequency and magnitude of Alaskan wildfires continue to increase due to climate change, understanding the health impacts will be imperative. A nuanced understanding of the effects of WFS on specific demographic and geographic groups facilitates data-driven public health interventions and fire management protocols that address these adverse health effects.

Geographic distribution of hospice, homecare, and nursing home facilities and access to end-of-life care among persons living with HIV/AIDS in Appalachia

BACKGROUND

Access to healthcare services, from diagnosis through end of life (EOL), is important among persons living with Human Immunodeficiency Syndrome (HIV) and Acquired Immunodeficiency Syndrome (AIDS) (PLWHA). However, little is known about the availability of hospice services in Appalachian areas. Therefore, the objective of this study is to describe the geographic distribution of hospice, homecare and nursing home facilities in order to demonstrate current existence of and access to resources for EOL care among PLWHA in the Appalachian regions of Tennessee and Alabama.

METHODS

This paper reports on the second aim of a larger sequential, mixed methods qualitative-quantitative (qual→quan) study. Data from advance care planning (ACP) surveys were collected by both electronic (n = 28) and paper copies (n = 201) and, among other things, obtained information on zip codes of residence of PLWHA. This enabled assessment of the geographic distribution of residences of PLWHA in relation to the distribution of healthcare services such as hospice and home healthcare services. Hospice and Home Healthcare data were obtained from the Tennessee and Alabama Departments of Health. The street addresses of these facilities were used to geocode and map the geographic distributions of the facilities using Street Map USA. Travel times to Hospice and Home Healthcare facilities were computed and mapped using ArcGIS 10.3.

RESULTS

We identified a total of 32 hospice and 69 home healthcare facilities in the Tennessee Appalachian region, while the Alabama Appalachian region had a total of 110 hospice and 86 home healthcare facilities. Most care facilities were located in urban centers. The distribution of care facilities was worse in Tennessee with many counties having no facilities, requiring up to an hour drive time to reach patients. A total of 86% of the PLWHA indicated preference to die at home.

CONCLUSIONS

Persons living with HIV/AIDS in Appalachia face a number of challenges at the end of life that make access to EOL services difficult. Although respondents indicated a preference to die at home, the hospice/homecare infrastructure and resources are overwhelmingly inadequate to meet this need. There is need to improve access to EOL care in the Appalachian regions of both Tennessee and Alabama although the need is greater in Tennessee.

Assessing inequalities in geographical access to emergency medical services in metropolitan Lisbon: a cross-sectional and ecological study

OBJECTIVES

Studies have suggested that material deprivation is strongly associated with negative health outcomes, and lower usage of various levels of healthcare. We aim to analyse geographical access to emergency medical services (EMSs) and hospital emergency units by EMS in relation to deprivation in the Lisbon Metropolitan Area (LMA), Portugal.

DESIGN

This study estimates road network-based access times from the centroids of statistical sections (census block groups equivalent) to locations of EMS and hospital emergency services. Each statistical section has been linked to a Material Deprivation Index (MDI). A non-parametric analysis of variance (ANOVA) was undertaken to compare MDI-linked statistical sections in terms of access to emergency care. Geographical access analysis was conducted for 2018.

PRIMARY OUTCOME MEASURE

Road network-based access time (in minutes) for EMSs to statistical sections and then on to emergency units in hospitals.

RESULTS

Overall, 82.4% of the LMA population is located less than a 10 min drive from an EMS without transport, and 99.1% from an EMS with transport. Travel time from EMS with transport to hospital is potentially less than 20 min for 95.2% of the population. However, 63.1% of residents living beyond a 30 min threshold (total time from emergency call to hospital arrival) are in areas with very high MDI (18.8% in high MDI, 13.3% in medium MDI, 4.7% in low MDI, 0% in very low MDI). Kruskal-Wallis ANOVA confirms discrepancies in access times between better-off and poorer areas.

CONCLUSION

Poorer areas experience worse geographical access to EMS and hospital emergency units. More research is needed to explore the quality of services and their outcomes, and to refine the analysis by focusing on specific vulnerable groups.

Sociodemographic Determinants of Acute Myocardial Infarction Hospitalization Risks in Florida

Background Identifying social determinants of myocardial infarction (MI) hospitalizations is crucial for reducing/eliminating health disparities. Therefore, our objectives were to identify sociodemographic determinants of MI hospitalization risks and to assess if the impacts of these determinants vary by geographic location in Florida. Methods and Results This is a retrospective ecologic study at the county level. We obtained data for principal and secondary MI hospitalizations for Florida residents for the 2005-2014 period and calculated age- and sex-adjusted MI hospitalization risks. We used a multivariable negative binomial model to identify sociodemographic determinants of MI hospitalization risks and a geographically weighted negative binomial model to assess if the strength of associations vary by location. There were 645 935 MI hospitalizations (median age, 72 years; 58.1%, men; 73.9%, white). Age- and sex-adjusted risks ranged from 18.49 to 69.48 cases/10 000 persons, and they were significantly higher in counties with low education levels (risk ratio [RR]=1.033, P<0.0001) and high divorce rate (RR, 0.995; P=0.018). However, they were significantly lower in counties with high proportions of rural (RR, 0.996; P<0.0001), black (RR, 1.026; P=0.032), and uninsured populations (RR, 0.983; P=0.040). Associations of MI hospitalization risks with education level and uninsured rate varied geographically (P for non-stationarity test=0.001 and 0.043, respectively), with strongest associations in southern Florida (RR for <high school education, 1.036-1.041; RR for uninsured rate, 0.971-0.976). Conclusions Black race, divorce, rural residence, low education level, and lack of health insurance were significant determinants of MI hospitalization risks, but associations with the latter 2 were stronger in southern Florida. Thus, interventions for addressing MI hospitalization risks need to prioritize these populations and allocate resources based on empirical evidence from global and local models for maximum efficiency and effectiveness.

Using spatially adaptive floating catchments to measure the geographic availability of a health care service: Pulmonary rehabilitation in the southeastern United States

A spatially adaptive floating catchment is a circular area that expands outward from a provider location until the estimated demand for services in the nearest population locations exceeds the observed number of health care services performed at the provider location. This new way of creating floating catchments was developed to address the change of spatial support problem (COSP) by upscaling the availability of the service observed at a provider location to the county-level so that its geographic association with utilization could be measured using the same spatial support. Medicare Fee-for-Service claims data were used to identify beneficiaries aged ≥ 65 years who received outpatient pulmonary rehabilitation (PR) in the Southeastern United States in 2014 (n = 8798), the number of PR treatments these beneficiaries received (n = 132,508), and the PR providers they chose (n = 426). The positive correlation between PR availability and utilization was relatively low, but statistically significant (r = 0.619, p < 0.001) indicating that most people use the nearest available PR services, but some travel long distances. SAFCs can be created using data from health care systems that collect claim-level utilization data that identifies the locations of providers chosen by beneficiaries of a specific health care procedure.

Factors Affecting the Location of Road Emergency Bases in Iran Using Analytical Hierarchy Process (AHP)

Objective

To identify and prioritize factors affecting the location of road emergency bases in Iran using Analytical Hierarchy Process (AHP).

Methods

This was a mixed method (quantitative-qualitative) study conducted in 2016. The participants in this study included the professionals and experts in the field of pre-hospital and road emergency services issues working in the Health Deputy of Iran Ministry of Health and Medical Education, which were selected using purposive sampling method. In this study at first, the factors affecting the location of road emergency bases in Iran were identified using literature review and conducting interviews with the experts. Then, the identified factors were scored and prioritized using the studied professionals and experts' viewpoints through using the analytic hierarchy process (AHP) technique and its related pair-wise questionnaire. The collected data were analyzed using MAXQDA 10.0 software to analyze the answers given to the open question and Expert Choice 10.0 software to determine the weights and priorities of the identified factors.

Results

The results showed that eight factors were effective in locating the road emergency bases in Iran from the viewpoints of the studied professionals and experts in the field of pre-hospital and road emergency services issues, including respectively distance from the next base, region population, topography and geographical situation of the region, the volume of road traffic, the existence of amenities such as water, electricity, gas, etc. and proximity to the village, accident-prone sites, University ownership of the base site, and proximity to toll-house.

Conclusion

Among the eight factors which were effective in locating the road emergency bases from the studied professionals and experts' perspectives, "distance from the next base" and "region population" were respectively the most important ones which had great differences with other factors.

Accessibility of tertiary hospitals in Finland: A comparison of administrative and normative catchment areas

The determination of an appropriate catchment area for a hospital providing highly specialized (i.e. tertiary) health care is typically a trade-off between ensuring adequate client volumes and maintaining reasonable accessibility for all potential clients. This may pose considerable challenges, especially in sparsely inhabited regions. In Finland, tertiary health care is concentrated in five university hospitals, which provide services in their dedicated catchment areas. This study utilizes Geographic Information Systems (GIS), together with grid-based population data and travel-time estimates, to assess the spatial accessibility of these hospitals. The current geographical configuration of the hospitals is compared to a normative assignment, with and without capacity constraints. The aim is to define optimal catchment areas for tertiary hospitals so that their spatial accessibility is as equal as possible. The results indicate that relatively modest improvements can be achieved in accessibility by using normative assignment to determine catchment areas.

Factors associated with awareness, treatment and control of hypertension in a disadvantaged rural Indian population

The aim of this study was to identify factors associated with awareness, treatment and control of hypertension in a rural setting in India. Following screening of the population, all individuals with hypertension (blood pressure (BP) ⩾140/90 mm Hg or taking antihypertensive medications) were invited to participate in this study. We measured BP, height, weight, skinfolds, waist and hip circumference, and administered a questionnaire to obtain information regarding socioeconomic and behavioural characteristics. Multivariable logistic regression was used to determine factors associated with awareness, treatment and control of hypertension. We recruited 277 individuals with hypertension. Awareness (43%), treatment (33%) and control (27%) of hypertension were poor. Greater distance to health services (odds ratio (OR) 0.56 (95% confidence interval (CI)) 0.32-0.98) was associated with poor awareness of hypertension while having had BP measured within the previous year (OR 4.72, 95% CI 2.71-8.22), older age and greater per cent body fat were associated with better awareness. Factors associated with treatment of hypertension were having had BP measured within the previous year (OR 6.18, 95% CI 3.23-11.82), age ⩾65 years, physical inactivity and greater per cent body fat. The only factor associated with control of hypertension was greater per cent body fat (OR 1.05, 95% CI 1.01-1.11). Improving geographic access and utilisation of health services should improve awareness and treatment of hypertension in this rural population. Further research is necessary to determine drivers of control.

The Tradeoff between Travel Time from Home to Hospital and Door to Balloon Time in Determining Mortality among STEMI Patients Undergoing PCI

BACKGROUND

In ST-segment elevation myocardial infarction (STEMI), even in presence of short door to balloon time (DTBT), timely reperfusion with percutaneous coronary intervention (PCI) is hampered by pre-hospital delays. Travel time (TT) constitutes a relevant part of these delays and may contribute to worse outcomes.

OBJECTIVE

To evaluate the relationship between TT from home to hospital and DTBT on 30-day mortality after PCI among patients with STEMI.

METHODS

We enrolled a cohort of 3,608 STEMI patients with a DTBT within 120 minutes who underwent PCI between years 2009 and 2013 in Lazio Region (Italy). We calculated the minimum travel time from residential address to emergency department where the first medical contact occurred. We defined system delay as the sum of travel time and DTBT time. Logistic regression models, including clinical and demographic characteristics were used to estimate the effect of TT and DTBT on mortality.

RESULTS

Among patients with 0-90 minutes of system delay, TT above the median value is positively associated with mortality (OR = 2.46; P = 0.009). Survival benefit associated with DTBT below the median results only among patients with TT below the median (OR for DTBT below the median = 0.39; P = 0.013), (OR for interaction between TT and DTBT = 2.36; p = 0.076).

CONCLUSION

TT affects survival after PCI for STEMI, even in the presence of health care systems compliant with current guidelines. Results emphasize the importance of health system initiatives to reduce pre-hospital delay. Utilization of TT can contribute to a better estimate of patient mortality risk in the evaluation of quality of care.

Investigating Barriers to Tuberculosis Evaluation in Uganda Using Geographic Information Systems

Reducing geographic barriers to tuberculosis (TB) care is a priority in high-burden countries where patients frequently initiate, but do not complete, the multi-day TB evaluation process. Using routine cross-sectional study from six primary-health clinics in rural Uganda from 2009 to 2012, we explored whether geographic barriers affect completion of TB evaluation among adults with unexplained chronic cough. We measured distance from home parish to health center and calculated individual travel time using a geographic information systems technique incorporating roads, land cover, and slope, and measured its association with completion of TB evaluation. In 264,511 patient encounters, 4,640 adults (1.8%) had sputum smear microscopy ordered; 2,783 (60%) completed TB evaluation. Median travel time was 68 minutes for patients with TB examination ordered compared with 60 minutes without (P < 0.010). Travel time differed between those who did and did not complete TB evaluation at only one of six clinics, whereas distance to care did not differ at any of them. Neither distance nor travel time predicted completion of TB evaluation in rural Uganda, although limited detail in road and village maps restricted full implementation of these mapping techniques. Better data are needed on geographic barriers to access clinics offering TB services to improve TB diagnosis.

Systemic lupus erythematosus observations of travel burden: A qualitative inquiry

AIMS

Explorations of travel impediments among patients suffering from rheumatic diseases have been very limited. Research has consistently indicated a shortage of rheumatologists, resulting in patients potentially having to travel long distances for care. The purpose of our study was to explore how systemic lupus erythematosus (SLE) patients experience travel issues differentially by race and socio-economic status.

METHODS

We conducted semi-structured interviews and a brief demographic survey with 10 patients diagnosed with SLE. Interview transcripts were coded and analyzed using NVivo Analysis Software to facilitate the reporting of recurrent themes and supporting quotations, and an initial codebook was independently developed by two researchers on the study team and then verified together.

RESULTS

Patients described three major areas of concern with respect to travel burden in accessing their rheumatologists: reliance on caregivers; meeting financial priorities; and pain and physical limitations.

CONCLUSIONS

Our data suggest general traveling challenges interfering with medical appointment compliance for several participants and the importance of socio-economic issues when considering travel issues. This study highlights an important area with implications for adherence to medical appointments and participation in research among patients with SLE.

A Review and Framework for Categorizing Current Research and Development in Health Related Geographical Information Systems (GIS) Studies

OBJECTIVES

The application of GIS in health science has increased over the last decade and new innovative application areas have emerged. This study reviews the literature and builds a framework to provide a conceptual overview of the domain, and to promote strategic planning for further research of GIS in health.

METHOD

The framework is based on literature from the library databases Scopus and Web of Science. The articles were identified based on keywords and initially selected for further study based on titles and abstracts. A grounded theory-inspired method was applied to categorize the selected articles in main focus areas. Subsequent frequency analysis was performed on the identified articles in areas of infectious and non-infectious diseases and continent of origin.

RESULTS

A total of 865 articles were included. Four conceptual domains within GIS in health sciences comprise the framework: spatial analysis of disease, spatial analysis of health service planning, public health, health technologies and tools. Frequency analysis by disease status and location show that malaria and schistosomiasis are the most commonly analyzed infectious diseases where cancer and asthma are the most frequently analyzed non-infectious diseases. Across categories, articles from North America predominate, and in the category of spatial analysis of diseases an equal number of studies concern Asia.

CONCLUSION

Spatial analysis of diseases and health service planning are well-established research areas. The development of future technologies and new application areas for GIS and data-gathering technologies such as GPS, smartphones, remote sensing etc. will be nudging the research in GIS and health.

Impact of living and socioeconomic characteristics on cardiovascular risk in ischemic stroke patients

OBJECTIVE

We aimed to stratify the risk of vascular event recurrence in patients with cerebral infarction according to living and socioeconomic characteristics and geographic region.

METHOD

The Outcomes in Patients with TIA and Cerebrovascular Disease (OPTIC) study is an international prospective study of patients aged 45 years or older who required secondary prevention of stroke [following either an acute transient ischemic attack, minor ischemic strokes, or recent (less than six-months previous), stable, first-ever, nondisabling ischemic stroke]. A total 3635 patients from 245 centers in 17 countries in four regions (Latin America, Middle East, North Africa, South Africa) were enrolled between 2007 and 2008. The outcome measure was the two-year rate of a composite of major vascular events (vascular death, myocardial infarction and stroke).

RESULTS

During the two-year follow-up period, 516 patients experienced at least one major cardiovascular event, resulting in an event rate of 15·6% (95% confidence interval 14·4-16·9%). Event rates varied across geographical region (P < 0·001), ranging from 13·0% in Latin America to 20·7% in North Africa. Unemployment status, living in a rural area, not living in fully serviced accommodation (i.e., house or apartment with its own electricity, toilet and water supply), no health insurance coverage, and low educational level (less than two-years of schooling) were predictors of major vascular events. Major vascular event rates steeply increased with the number of low-quality living/socioeconomic conditions (from 13·4% to 47·9%, adjusted P value for trend <0·001).

CONCLUSION

Vascular risk in stroke patients in low- and middle-income countries varies not only with the number of arterial beds involved but also with socioeconomic variables.

Primary Stroke Centers Should Be Located Using Maximal Coverage Models for Optimal Access

Background and Purpose—

The current self-initiated approach by which hospitals acquire Primary Stroke Center (PSC) certification provides insufficient coverage for large areas of the United States. An alternative, directed, algorithmic approach to determine near optimal locations of PSCs would be justified if it significantly improves coverage.

Methods—

Using geographic location–allocation modeling techniques, we developed a universal web-based calculator for selecting near optimal PSC locations designed to maximize the population coverage in any state. We analyzed the current PSC network population coverage in Iowa and compared it with the coverage that would exist if a maximal coverage model had instead been used to place those centers. We then estimated the expected gains in population coverage if additional PSCs follow the current self-initiated model and compared it against the more efficient coverage expected by use of a maximal coverage model to select additional locations.

Results—

The existing 12 self-initiated PSCs in Iowa cover 37% of the population, assuming a time–distance radius of 30 minutes. The current population coverage would have been 47.5% if those 12 PSCs had been located using a maximal coverage model. With the current self-initiated approach, 54 additional PSCs on average will be needed to improve coverage to 75% of the population. Conversely, only 31 additional PSCs would be needed to achieve the same degree of population coverage if a maximal coverage model is used.

Conclusion—

Given the substantial gain in population access to adequate acute stroke care, it appears justified to direct the location of additional PSCs or recombinant tissue-type plasminogen activator-capable hospitals through a maximal coverage model algorithmic approach.

Measuring geographic access to health care: raster and network-based methods

Background

Inequalities in geographic access to health care result from the configuration of facilities, population distribution, and the transportation infrastructure. In recent accessibility studies, the traditional distance measure (Euclidean) has been replaced with more plausible measures such as travel distance or time. Both network and raster-based methods are often utilized for estimating travel time in a Geographic Information System. Therefore, exploring the differences in the underlying data models and associated methods and their impact on geographic accessibility estimates is warranted.

Methods

We examine the assumptions present in population-based travel time models. Conceptual and practical differences between raster and network data models are reviewed, along with methodological implications for service area estimates. Our case study investigates Limited Access Areas defined by Michigan’s Certificate of Need (CON) Program. Geographic accessibility is calculated by identifying the number of people residing more than 30 minutes from an acute care hospital. Both network and raster-based methods are implemented and their results are compared. We also examine sensitivity to changes in travel speed settings and population assignment.

Results

In both methods, the areas identified as having limited accessibility were similar in their location, configuration, and shape. However, the number of people identified as having limited accessibility varied substantially between methods. Over all permutations, the raster-based method identified more area and people with limited accessibility. The raster-based method was more sensitive to travel speed settings, while the network-based method was more sensitive to the specific population assignment method employed in Michigan.

Conclusions

Differences between the underlying data models help to explain the variation in results between raster and network-based methods. Considering that the choice of data model/method may substantially alter the outcomes of a geographic accessibility analysis, we advise researchers to use caution in model selection. For policy, we recommend that Michigan adopt the network-based method or reevaluate the travel speed assignment rule in the raster-based method. Additionally, we recommend that the state revisit the population assignment method.

Gender difference in stroke case fatality: an integrated study of hospitalization and mortality

BACKGROUND

Providing regional and state-specific prognosis factors for stroke patients has both clinical and public health importance. Results from previous studies of sex difference in stroke case fatality have been mixed. The current study links stroke hospitalizations to community-based mortality records to examine sex difference in stroke case fatality and associated prognosis factors.

METHODS

Hospital discharge data and death certificate data from January 2005 to December 2009 in Nebraska were linked. Multivariable logistic regression was used to estimate sex differences in 30-day mortality, and the Cox proportional hazard model was used to predict overall survival.

RESULTS

A total of 15,806 patients were included. Females were more likely to die during the 30 days after stroke hospitalization. However, there was no significant difference in overall survival in the multivariate analysis that controlled for age, comorbidity, and rehabilitation factors. Females were more likely to have comorbidities, such as atrial fibrillation, anemia, and heart failure, while males were more likely to have chronic kidney disease. In addition, males were more likely to receive rehabilitation services after stroke.

CONCLUSIONS

Among persons hospitalized with a stroke in Nebraska between 2005 and 2009, the crude case fatality rate was 50% higher in women. However, after accounting for age and other variables, adjusted mortality rates were essentially the same for men and women.

Temporal changes in geographic disparities in access to emergency heart attack and stroke care: are we any better today?

The objective of this study was to investigate temporal changes in geographic access to emergency heart attack and stroke care. Network analysis was used to compute travel time to the nearest emergency room (ER), cardiac, and stroke centers in Middle Tennessee. Populations within 30, 60, and 90 min driving time to the nearest ER, cardiac and stroke centers were identified. There were improvements in timely access to cardiac and stroke centers over the study period (1999-2010). There were significant (p<0.0001) increases in the proportion of the population with access to cardiac centers within 30 min from 29.4% (1999) to 62.4% (2009) while that for stroke changed from 5.4% (2004) to 46.1% (2010). Most (96%) of the population had access to an ER within 30 min from 1999 to 2010. Access to care has improved in the last decade but more still needs to be done to address disparities in rural communities.