Socioeconomic disadvantage and acute coronary events: a spatiotemporal analysis

The COVID-19 impact on STEMI disparities

ST-segment elevation myocardial infarction (STEMI) is a significant source of morbidity and mortality. Despite guideline-driven management and increased awareness of social determinants of health, there are persistent disparities in diagnosis, management, and outcomes. The coronavirus disease 2019 (COVID-19) pandemic has greatly affected emergency department visitation, conditions and throughput. The aim of this study was to find any potential health disparities in patients who presented with STEMI during the COVID-19 pandemic by reviewing STEMI care data from April to September 2019 (pre-pandemic) and April to September 2020 (during the pandemic) for our hospital system. Patients with STEMI within 12 h of presentation were included in this study, and subdivided by age, gender, and race/ethnicity. We compared the turnaround times between emergency department arrival to intervention (electrocardiogram or catheterization) within the patient subgroups to find any notable differences. No statistically significant changes in turnaround times during either study period were found based on age, gender, or race/ethnicity for the STEMI interventions despite shifts in emergency department resources during the pandemic. This study helped assess the status quo in STEMI intervention for our health system and serves as a baseline for us to monitor gaps in care or areas of improvement. As healthcare systems institute new measures to promote equitable care, such as improving the accuracy of demographic data capture, establishing a baseline is an essential first step in evaluating the impact of these measures.

Socioeconomic disadvantage and long-term survival duration in out-of-hospital cardiac arrest patients: A population-based cohort study

Background

Socioeconomic status (SES) is a well-established determinant of cardiovascular health. However, the relationship between SES and clinical outcomes in long-term out-of-hospital cardiac arrest (OHCA) is less well-understood. The Singapore Housing Index (SHI) is a validated building-level SES indicator. We investigated whether SES as measured by SHI is associated with long-term OHCA survival in Singapore.

Methods

We conducted an open cohort study with linked data from the Singapore Pan-Asian Resuscitation Outcomes Study (PAROS), and the Singapore Registry of Births and Deaths (SRBD) from 2010 to 2020. We fitted generalized structural equation models, calculating hazard ratios (HRs) using a Weibull model. We constructed Kaplan-Meier survival curves and calculated the predicted marginal probability for each SHI category.

Results

We included 659 cases. In both univariable and multivariable analyses, SHI did not have a significant association with survival. Indirect pathways of SHI mediated through covariates such as Emergency Medical Services (EMS) response time (HR of low-medium, high-medium and high SHI when compared to low SHI: 0.98 (0.88-1.10), 1.01 (0.93-1.11), 1.02 (0.93-1.12) respectively), and age of arrest (HR of low-medium, high-medium and high SHI when compared to low SHI: 1.02 (0.75-1.38), 1.08 (0.84-1.38), 1.18 (0.91-1.54) respectively) had no significant association with OHCA survival. There was no clear trend in the predicted marginal probability of survival among the different SHI categories.

Conclusions

We did not find a significant association between SES and OHCA survival outcomes in residential areas in Singapore. Among other reasons, this could be due to affordable healthcare across different socioeconomic classes.

Forecasting of overall and aggressive prostate cancer incident counts at the small area level

OBJECTIVES

This study aims to forecast overall and aggressive prostate cancer counts at the local government area (LGA) level over 10 years (2019-2028) in Victoria, Australia, using Victorian Cancer Registry (2001-2018) data.

METHODS

We used the Age-Period-Cohort approach to estimate the annual age-specific incidence and used Bayesian spatiotemporal models that account for non-linear temporal trends and area-level risk factors. We evaluated the models' performance by withholding and comparing forecasts with the 2014-2018 data.

RESULTS

There were 80,449 prostate cancer cases between 2001 and 2018, with an overall increasing trend. Compared to 2001, prostate cancer incidence increased by 69%, from 3049 to 5167 cases in 2018. Prostate cancer counts are expected to reach 7631 cases in 2028, a further 48% increase. Unexplained area-level spatial variation was substantially reduced after adjusting for the area-level elderly population. Aggressive prostate cancer cases increased by 107% between 2001 and 2018 and are expected to rise by 123% increase in 2028. The proportion of aggressive prostate cancer cases will increase to 31% in 2028 from 20% in 2018. By 2028, overall and aggressive prostate cancer cases are projected to be increasing in 66% and 61% of LGAs.

CONCLUSION

Prostate cancer cases are projected to rise at the state level and most LGAs in the next 10 years, with much steeper increases in aggressive cases. Population growth and an ageing population have primarily contributed to this rise besides prostate-specific antigen testing. These prediction estimates help inform prostate cancer burden and facilitate efficient healthcare delivery.

Forecasting of Lung Cancer Incident Cases at the Small-Area Level in Victoria, Australia

Predicting lung cancer cases at the small-area level is helpful to quantify the lung cancer burden for health planning purposes at the local geographic level. Using Victorian Cancer Registry (2001-2018) data, this study aims to forecast lung cancer counts at the local government area (LGA) level over the next ten years (2019-2028) in Victoria, Australia. We used the Age-Period-Cohort approach to estimate the annual age-specific incidence and utilised Bayesian spatio-temporal models that account for non-linear temporal trends and area-level risk factors. Compared to 2001, lung cancer incidence increased by 28.82% from 1353 to 1743 cases for men and 78.79% from 759 to 1357 cases for women in 2018. Lung cancer counts are expected to reach 2515 cases for men and 1909 cases for women in 2028, with a corresponding 44% and 41% increase. The majority of LGAs are projected to have an increasing trend for both men and women by 2028. Unexplained area-level spatial variation substantially reduced after adjusting for the elderly population in the model. Male and female lung cancer cases are projected to rise at the state level and in each LGA in the next ten years. Population growth and an ageing population largely contributed to this rise.

Trends in Ischaemic Heart Disease in Australia, 2001-2015: A Comparison of Urban and Rural Populations

OBJECTIVE

Ischaemic heart disease (IHD) is a major source of disease burden worldwide. Recent trends show incidence is declining but it is unclear whether the trends are similar in urban and rural populations. This study examines the trends of IHD events (i.e. hospitalisations and deaths) in New South Wales, Australia by rurality.

METHODS

This was a retrospective analysis of linked administrative data for hospitalisation and death records across NSW between 2001 and 2015. Participants were NSW residents aged 15-105 years who died or were hospitalised with a principal diagnosis of IHD. The main outcome measures were annual age-standardised mortality and hospitalisations for IHD by calendar year and rurality.

RESULTS

Between 2001 and 2015, age-standardised annual IHD hospitalisations declined in urban areas from 587 to 260 and in rural areas from 766 to 395 per 100,000 people. The annual decline in hospitalisations was greater in urban than rural areas, with Annual Percentage Change (APC) of -5.6% (95% CI, -6.1%, -5.0%) and -4.5% (95% CI, -5.0%, -4.0%), respectively (p=0.012). Ischaemic heart disease mortality declined at a similar rate in urban and rural regions (APC -7.6% and -6.7% per annum, p=0.28). Absolute inequalities in IHD deaths persisted until 2015 when there were 49 (urban) and 70 (rural) IHD deaths per 100,000 people.

CONCLUSIONS

Ischaemic heart disease hospitalisations and mortality have declined considerably between 2001 and 2015 in both rural and urban areas, yet inequalities persist, suggesting more intensive preventive efforts are required to further reduce the burden of IHD in rural populations.

Geographical variation of diabetic emergencies attended by prehospital Emergency Medical Services is associated with measures of ethnicity and socioeconomic status

Geographical variation of diabetic emergencies attended by prehospital emergency medical services (EMS) and the relationship between area-level social and demographic factors and risk of a diabetic emergency were examined. All cases of hypoglycaemia and hyperglycaemia attended by Ambulance Victoria between 1/01/2009 and 31/12/2015 were tabulated by Local Government Area (LGA). Conditional autoregressive models were used to create smoothed maps of age and gender standardised incidence ratio (SIR) of prehospital EMS attendance for a diabetic emergency. Spatial regression models were used to examine the relationship between risk of a diabetic emergency and area-level factors. The areas with the greatest risk of prehospital EMS attendance for a diabetic emergency were disperse. Area-level factors associated with risk of a prehospital EMS-attended diabetic emergency were socioeconomic status (SIR 0.70 95% CrI [0.51, 0.96]), proportion of overseas-born residents (SIR 2.02 95% CrI [1.37, 2.91]) and motor vehicle access (SIR 1.47 95% CrI [1.08, 1.99]). Recognition of areas of increased risk of prehospital EMS-attended diabetic emergencies may be used to assist prehospital EMS resource planning to meet increased need. In addition, identification of associated factors can be used to target preventative interventions tailored to individual regions to reduce demand.

Urbanization is Associated with Increased Trends in Cardiovascular Mortality Among Indigenous Populations: the PAI Study

Background

The cardiovascular risk burden among diverse indigenous populations is not totally known and may be influenced by lifestyle changes related to the urbanization process.

Objectives

To investigate the cardiovascular (CV) mortality profile of indigenous populations during a rapid urbanization process largely influenced by governmental infrastructure interventions in Northeast Brazil.

Methods

We assessed the mortality of indigenous populations (≥ 30 y/o) from 2007 to 2011 in Northeast Brazil (Bahia and Pernambuco states). Cardiovascular mortality was considered if the cause of death was in the ICD-10 CV disease group or if registered as sudden death. The indigenous populations were then divided into two groups according to the degree of urbanization based on anthropological criteria:^9,10 Group 1 - less urbanized tribes (Funi-ô, Pankararu, Kiriri, and Pankararé); and Group 2 - more urbanized tribes (Tuxá, Truká, and Tumbalalá). Mortality rates of highly urbanized cities (Petrolina and Juazeiro) in the proximity of indigenous areas were also evaluated. The analysis explored trends in the percentage of CV mortality for each studied population. Statistical significance was established for p value < 0.05.

Results

There were 1,333 indigenous deaths in tribes of Bahia and Pernambuco (2007-2011): 281 in Group 1 (1.8% of the 2012 group population) and 73 in Group 2 (3.7% of the 2012 group population), CV mortality of 24% and 37%, respectively (p = 0.02). In 2007-2009, there were 133 deaths in Group 1 and 44 in Group 2, CV mortality of 23% and 34%, respectively. In 2009-2010, there were 148 deaths in Group 1 and 29 in Group 2, CV mortality of 25% and 41%, respectively.

Conclusions

Urbanization appears to influence increases in CV mortality of indigenous peoples living in traditional tribes. Lifestyle and environmental changes due to urbanization added to suboptimal health care may increase CV risk in this population.

Quantifying the role of modifiable risk factors in the differences in cardiovascular disease mortality rates between metropolitan and rural populations in Australia: a macrosimulation modelling study

OBJECTIVES

The study aimed (1) to quantify differences in modifiable risk factors between urban and rural populations, and (2) to determine the number of rural cardiovascular disease (CVD) and ischaemic heart disease (IHD) deaths that could be averted or delayed if risk factor levels in rural areas were equivalent to metropolitan areas.

SETTING

National population estimates, risk factor prevalence, CVD and IHD deaths data were analysed by rurality using a macrosimulation Preventable Risk Integrated Model for chronic disease risk. Uncertainty analysis was conducted using a Monte Carlo simulation of 10 000 iterations to calculate 95% credible intervals (CIs).

PARTICIPANTS

National data sets of men and women over the age of 18 years living in urban and rural Australia.

RESULTS

If people living in rural Australia had the same levels of risk factors as those in metropolitan areas, approximately 1461 (95% CI 1107 to 1791) deaths could be delayed from CVD annually. Of these CVD deaths, 793 (95% CI 506 to 1065) would be from IHD. The IHD mortality gap between metropolitan and rural populations would be reduced by 38.2% (95% CI 24.4% to 50.6%).

CONCLUSIONS

A significant portion of deaths from CVD and IHD could be averted with improvements in risk factors; more than one-third of the excess IHD deaths in rural Australia were attributed to differences in risk factors. As much as two-thirds of the increased IHD mortality rate in rural areas could not be accounted for by modifiable risk factors, however, and this requires further investigation.

Socioeconomic Equity in the Receipt of In-Hospital Care and Outcomes in Australian Acute Coronary Syndrome Patients: The CONCORDANCE Registry

BACKGROUND

Socioeconomic status (SES) is a social determinant of both health and receipt of health care services, but its impact is under-studied in acute coronary syndrome (ACS). The aim of this study was to examine the influence of SES on in-hospital care, and clinical events for patients presenting with an ACS to public hospitals in Australia.

METHODS

Data from 9064 ACS patient records were collected from 41 public hospitals nationwide from 2009 as part of the Cooperative National Registry of Acute Coronary Syndrome Care (CONCORDANCE) registry. For this analysis, we divided the cohort into four socioeconomic groups (based on postcode of usual residence) and compared the in-hospital care provided and clinical outcomes before and after adjustment for both patient clinical characteristics and hospital clustering.

RESULTS

Patients were divided into four SES groups (from the most to the least disadvantaged: 2042 (23%) vs. 2104 (23%) vs. 1994 (22%) vs. 2968 (32%)). Following adjustments for patient characteristics, there were no differences in the odds of receiving coronary angiogram, revascularisation, prescription of recommended medication, or referral to cardiac rehabilitation across the SES groups (p=0.06, 0.69, 0.89 and 0.79, respectively). After adjustment for clinical characteristics, no associations were observed for in-hospital and cumulative death (p=0.62 and p=0.71, respectively). However, the most disadvantaged group were 37% more likely to have a major adverse cardiovascular event (MACE) than the least disadvantaged group (OR (95% CI): 1.37 (1.1, 1.71), p=0.02) driven by incidence of in-hospital heart failure.

CONCLUSIONS

Although there may be gaps in the delivery of care, this delivery of care does not differ by patient's SES. It is an encouraging affirmation that all patients in Australian public hospitals receive equal in-hospital care, and the likelihood of death is comparable between the SES groups.

Rural Inequalities in the Australian Burden of Ischaemic Heart Disease: A Systematic Review

OBJECTIVE

To summarise all available evidence on the differences in burden of ischaemic heart disease (IHD) between metropolitan and rural communities of Australia.

METHODS

Systematic review of peer-reviewed literature published between 1990 and 2014. Search terms were derived from the four major topics: (1) rural; (2) ischaemic heart disease; (3) Australia; and (4) burden of disease. Terms were adapted for six databases and two independent researchers screened results. Studies were included if they compared outcomes related to IHD in adults aged 18 years and over, between (at least) two areas of differing remoteness, at the same point in time.

RESULTS

Twenty studies were included and presented data collected between 1969 and 2010. Seventeen studies showed a clear disparity in IHD outcomes between major cities and regional and remote areas, with a consistently higher burden observed outside major cities. Among Aboriginal and Torres Strait Islander populations, fewer differences were observed and some IHD outcomes were not associated with remoteness.

CONCLUSIONS

Populations outside of major cities in Australia bear a disproportionately high burden of ill health due to IHD, yet the majority of the rural populations are yet to be investigated in terms of burden of disease outcomes from IHD.

IMPLICATIONS

Remoteness is a key determinant of IHD burden in Australia. The reasons for increased IHD burden in rural compared to metropolitan communities of Australia are poorly understood, which has implications for the design of targeted interventions to reduce geographical inequalities.

Derivation of indices of socioeconomic status for health services research in Asia

Background

Environmental contexts have been shown to predict health behaviours and outcomes either directly or via interaction with individual risk factors. In this paper, we created indexes of socioeconomic disadvantage (SEDI) and socioeconomic advantage (SAI) in Singapore to test the applicability of these concepts in an Asian context. These indices can be used for health service resource allocation, research and advocacy.

Methods

We used principal component analysis (PCA) to create SEDI and SAI using a structured and iterative process to identify and include influential variables in the final index. Data at the master plan geographical level was obtained from the most recent Singapore census 2010.

Results

The 3 areas with highest SEDI scores were Outram (120.1), followed by Rochor (111.0) and Downtown Core (110.4). The areas with highest SAI scores were Tanglin, River Valley and Newton. The SAI had 89.6% of variation explained by the final model, as compared to 67.1% for SEDI, and we recommend using both indices in any analysis.

Conclusion

These indices may prove useful for policy-makers to identify spatially varying risk factors, and in turn help identify geographically targeted intervention programs, which can be more cost effective to conduct.

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Areal measures of socioeconomic status can help in resource allocation.

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Our study creates such indices in an Asian context.

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These indices can be used for health service research in Asian countries.

Differences in undergoing cardiac procedures within three months after first myocardial infarction by country of birth in women and men: a Swedish national cohort study

OBJECTIVE

To examine the relationship between country of birth and the utilization of coronary angiography, percutaneous coronary intervention (PCI) and coronary artery bypass graft (CABG) after a first-time myocardial infarction (MI).

DESIGN, SETTING AND PATIENTS

117,494 MI patients of all ages who were admitted to coronary care units between 2001 and 2009 in Sweden were followed-up for three months after admission.

MAIN OUTCOME MEASURES

Undergoing coronary angiography, PCI or CABG after first-time MI.

RESULTS

proportion of patients undergoing angiography and PCI increased whereas proportion of patients undergoing CABG also delay time for all three procedures decreased over the study period. The proportion of women undergoing any of the three procedures was markedly lower and delay time longer than those of men regardless of study period and migration background. Overall foreign-born first MI patients had higher rate of angiography (HR = 1.30, 95% CI: 1.27-1.33), PCI (HR = 1.27, 95% CI: 1.24-1.30) and CABG (HR = 1.21, 95% CI: 1.15-1.28) compared with Sweden born first MI patients. After controlling for potential confounding factors in multivariable models, the overall differences vanished for angiography and reduced markedly for PCI and CABG. However, multivariable stratified analysis by specific country of birth yielded higher rate of angiography among men born in Uganda (HR = 2.11, 95% CI: 1.00-4.43) and Peru (HR = 1.98, 95% CI: 1.07-3.68) and lower rate among men born in Croatia (HR = 0.71, 95% CI: 0.52-0.99) and women born in Thailand (HR = 0.49, 95% CI: 0.35-0.94). PCI adjusted rates were higher among women born in Palestine state (HR = 2.44, 95% CI: 1.15-5.16), Iraq (HR = 1.34, 95% CI: 1.04-1.74) and Poland (HR = 1.21, 95% CI: 1.02-1.44) and rate of CABG was higher among immigrants from some parts of Asia, including men born in Sri Lanka (HR = 3.19, 95% CI: 1.43-7.12), India (HR = 1.95, 95% CI: 1.21-3.14), Vietnam (HR = 2.65, 95% CI: 1.32-5.33), Palestine State (HR = 2.11, 95% CI: 1.06-4.24), and women born in Syria (HR = 2.36, 95% CI: 1.25-4.45), Iraq (HR = 1.74, 95% CI: 1.02-2.94), and Turkey (HR = 1.70, 95% CI: 1.03-2.79).

CONCLUSIONS

The observed high rate of CABG for immigrants and particularly those born in some Asian countries was not explained by the potential confounding factors. A more severe coronary disease in this population might explain this high rate but needs further research. Awareness and subsequent intervention at earlier stage of coronary disease among immigrants could prolong their life and reduce the healthcare costs.

Neighborhood socioeconomic and racial disparities in angiography and coronary revascularization: the ARIC surveillance study

PURPOSE

Disparities in the receipt of angiography and subsequent coronary revascularization have not been well-studied.

METHODS

We estimated prevalence ratios and 95% confidence intervals (PR, 95% CIs) for the association between neighborhood-level income (nINC) and receipt of angiography; and among those undergoing angiography, receipt of revascularization procedures, among 9941 hospitalized myocardial infarction patients under epidemiologic surveillance by the Atherosclerosis Risk in Communities Study (1993-2002).

RESULTS

In analyses by tertile of nINC controlling for age, study community, gender, and year, compared with white patients from high nINC areas, black patients from low nINC (0.60, 0.54-0.66) and medium nINC (0.70, 0.60-0.78) areas, as well as white patients from low nINC areas (0.83, 0.75-0.91) were less likely to receive angiography, whereas black patients from high nINC and white patients from medium nINC areas were not. Associations were attenuated, but persisted, after we controlled for event severity, medical history, receipt of Medicaid, and hospital type. Compared with high nINC white patients, black patients were less likely, and white patients were as likely, to undergo cardiac revascularization, given receipt of an angiogram.

CONCLUSIONS

Black and lower nINC patients were less likely to undergo angiography than were white patients and those from higher nINC areas. Among those receiving angiography, race, but not nINC, gradients persisted.

Geographical variation in ambulance calls is associated with socioeconomic status

OBJECTIVES

  The main objective was to explore the relationship between socioeconomic status and the spatial distribution of ambulance calls, as modeled in the island nation of Singapore, at the Development Guide Plan (DGP) level (equivalent to census tracts in the United States).

METHODS

  Ambulance call data came from a nationwide registry from January to May 2006. We used a conditional autoregressive (CAR) model to create smoothed maps of ambulance calls at the DGP level, as well as spatial regression models to evaluate the relationship between the risk of calls with regional measures of socioeconomic status, such as household type and both personal and household income.

RESULTS

  There was geographical correlation in the ambulance calls, as well as a socioeconomic gradient in the relationship with ambulance calls of medical-related (but not trauma-related) reasons. For instance, the relative risk (RR) of medical ambulance calls decreased by a factor of 0.66 (95% credible interval [CrI] = 0.56 to 0.79) for every 10% increase in the proportion of those with monthly household income S$5000 and above. The top three DGPs with the highest risk of medical-related ambulance calls were Changi (RR = 29, 95% CrI = 24 to 35), downtown core (RR = 8, 95% CrI = 6 to 9), and Orchard (RR = 5, 95% CrI = 4 to 6).

CONCLUSIONS

  This study demonstrates the utility of geospatial analysis to relate population socioeconomic factors with ambulance call volumes. This can serve as a model for analysis of other public health systems.

A small-area ecologic study of myocardial infarction, neighborhood deprivation, and sex: a Bayesian modeling approach

BACKGROUND

Socioeconomic inequalities in the risk of coronary heart disease (CHD) are well documented for men and women. CHD incidence is greater for men but its association with socioeconomic status is usually found to be stronger among women. We explored the sex-specific association between neighborhood deprivation level and the risk of myocardial infarction (MI) at a small-area scale.

METHODS

We studied 1193 myocardial infarction events in people aged 35-74 years in the Strasbourg metropolitan area, France (2000-2003). We used a deprivation index to assess the neighborhood deprivation level. To take into account spatial dependence and the variability of MI rates due to the small number of events, we used a hierarchical Bayesian modeling approach. We fitted hierarchical Bayesian models to estimate sex-specific relative and absolute MI risks across deprivation categories. We tested departure from additive joint effects of deprivation and sex.

RESULTS

The risk of MI increased with the deprivation level for both sexes, but was higher for men for all deprivation classes. Relative rates increased along the deprivation scale more steadily for women and followed a different pattern: linear for men and nonlinear for women. Our data provide evidence of effect modification, with departure from an additive joint effect of deprivation and sex.

CONCLUSIONS

We document sex differences in the socioeconomic gradient of MI risk in Strasbourg. Women appear more susceptible at levels of extreme deprivation; this result is not a chance finding, given the large difference in event rates between men and women.

Psychosocial predictors of change in quality of life in patients after coronary interventions

OBJECTIVE

Health-related quality of life (HRQOL) after coronary interventions (coronary artery bypass grafting, percutaneous transluminal coronary angioplasty) usually improves in patients, but not in all patients. Some patients actually show a significant decline in HRQOL. Our aim was to explore the potential of psychologic well-being (anxiety, depression), vital exhaustion, Type D personality, and socioeconomic position as predictors of HRQOL in patients with coronary disease.

METHODS

A total of 106 patients scheduled for coronary angiography were interviewed before (baseline) and 12 to 24 months after coronary angiography. Socioeconomic status was evaluated by education. The General Health Questionnaire 28 was used for measuring psychologic well-being (anxiety, depression), the Maastricht interview was used for measuring vital exhaustion, and the Type D questionnaire was used for measuring personality. HRQOL was assessed using the Short Form-36 (physical and mental components) questionnaire. Functional status was assessed with a combination of New York Heart Association and Canadian Cardiovascular Society classifications. Linear regressions were used to analyze data.

RESULTS

A change in physical HRQOL was predicted by baseline psychologic well-being (β = -.39; 95% confidence interval [CI], -1.00 to -.16) and baseline HRQOL (β = -.61; 95% CI, -.83 to -.34). A change in mental HRQOL was predicted by (baseline) psychologic well-being (β = -.37; 95% CI, -.99 to -.09), vital exhaustion (β = -.21; 95% CI, -.69 to -.03), and baseline HRQOL (β = -.76; 95% CI, -1.03 to -.44). Ejection fraction did not significantly predict HRQOL.

CONCLUSION

Psychosocial factors (psychologic well-being, vital exhaustion) seem to be more important predictors of change in HRQOL compared with some objective medical indicators (ejection fraction) among patients with coronary disease.