Socioeconomic and Cardiovascular Variables Explaining Regional Variations in Stroke Mortality in Chile: An Ecological Study

Trends in Mortality from Stroke in Latin America and the Caribbean, 1979–2015

Background:

Stroke is the second largest single cause of death and disability in Latin America and the Caribbean (LAC). There have been large overall declines in stroke mortality rates in most LAC countries in recent decades.

Objective:

To analyze trends in mortality caused by stroke in LAC countries in the period 1979–2015.

Methods:

We extracted data for age-standardized stroke mortality rates per 100,000 in LAC for the period 1979–2015 from the World Health Organization Mortality Database. Joinpoint regression was used to analyze the trends and compute the annual percent change (APC) in LAC as a whole and by country. Analyses were conducted by gender, region and World Bank income classification.

Results:

Mortality from stroke has decreased in LAC over the study period by an average APC of –1.9%. Most countries showed significant downward trends, with the sharpest decreases in Chile, Colombia and Uruguay. We recorded statistically significant decreases of –1.4% and –2.4% in mortality rates in men and women, respectively, in the whole LAC. Southern and high-income countries showed the steepest decreases.

Conclusions:

Stroke mortality has decreased in LAC, in both sexes, especially in southern and high-income countries. Our results could serve as a reference for the development of primary prevention and acute management of stroke policies focused on countries with higher mortality.

Incidence, risk factors, prognosis, and health-related quality of life after stroke in a low-resource community in Chile (ÑANDU): a prospective population-based study

BACKGROUND

Stroke is a leading cause of disability and death worldwide. The best estimates of local, national, and global burden of stroke are derived from prospective population-based studies. We aimed to investigate the incidence, risk factors, long-term prognosis, care, and quality of life after stroke in the Ñuble region of Chile.

METHODS

We did a prospective community-based study with use of multiple overlapping sources of hospitalised, ambulatory, and deceased cases. Standardised diagnostic criteria were used to identify and follow up all cases occurring in the resident population of the Ñuble region, Chile (in a low-income rural-urban population including predominantly people of Indigenous-European heritage), for 1 year. Participants were included if they had a clinical diagnosis of stroke confirmed according to the study criteria. All cases were adjudicated by vascular neurologists. Incidence rates of first-ever stroke were calculated from the population of Ñuble according to the 2017 national census.

FINDINGS

From April 1, 2015, to March 31, 2016, we ascertained 1103 stroke cases, of which 890 (80·7%) were first-ever incident cases. The mean age of patients with first-ever stroke was 70·3 years (SD 14·1) and 443 (49·8%) were women. A CT scan was obtained in 801 (90%) of 890 patients (mean time from symptom onset to scan of 13·4 h (SD 29·8). The incidence of first-ever stroke age-adjusted to the world population was 121·7 (95% CI 113·7-130·1) per 100 000. The age-adjusted incidence rates, per 100 000 inhabitants, by main pathological subtypes were as follows: ischaemic stroke (101·5 [95% CI 90·9-113·0]); intracerebral haemorrhage (17·9 [13·5-23·4]), and subarachnoid haemorrhage (4·2 [2·1-7·3]). The 30-day case-fatality rate was 24·6% (21·9-27·6). At 6 months after the stroke, 55·9% (432 of 773) of cases had died or were disabled, which increased to 61·0% (456 of 747) at 12 months. Health-related quality of life in survivors was low at 6 months, improving slightly at 12 months after the stroke.

INTERPRETATION

The incidence of stroke in this low-resource population was higher than our previous finding in northern Chile and within the mid-range of most population-based stroke studies. This result was due mainly to a higher incidence of ischaemic stroke, probably associated with increasing age and a high prevalence of cardiometabolic risk factors in the population studied. Our findings suggest that more should be done for the prevention and care of stroke in communities like the Ñuble population.

FUNDING

The National Agency for Research and Development and the Technology-Health Research Fund, Clínica Alemana de Santiago, Boehringer Ingelheim, Bristol Meyers Squibb, The Herminda Martin Clinical Hospital of Chillán, Universidad Mayor, and Universidad de Concepción.

[Prevalence and characteristics of metabolic syndrome in adults admitted to a health care center for ischemic stroke]

Introduction

Background: Chile has experienced an increase in the prevalence of metabolic syndrome (MS) among the adult population. MS is proposed as a predictor for the occurrence of vascular defects causing ischemic stroke. Objective: to determine the frequency and characteristics of MS in a sample of adults after an ischemic ACV. Methods: a descriptive, cross-sectional study that consisted of reviewing variables related to MS in 180 adult patients admitted to a clinic for an ischemic stroke between the years 2011 and 2017. Weight and height measurements were considered to obtain BMI and nutritional status. Waist circumference (CC), systolic (PAS) and diastolic blood pressure (PAD), total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides (TG), and glycemia were also measured. Results: 62.8 % of the sample had MS. BMI (CI, 28.5-29.9; p = 0.001), CC (CI, 101.3-105.3; p = 0.001), PAS (CI, 147.4-155.7; p = 0.000), PAD (CI, 87.7-93.6; p = 0.000), glycemia (CI, 132.9-159.2; p = 0.000), and TG (CI, 181.2-228.8; p = 0.000) were higher in the group with SM. HDL-cholesterol (CI, 35.5-39.2; p = 0.000) was lower in this same group. Older age (p = 0.007), male gender (p = 0.017), and excess nutritional status (p = 0.000) had a positive association with MS. Of the subjects with MS, there were no differences obtained when comparing the components that define MS between men and women. Conclusion: our findings reveal a high frequency of MS in adults admitted to a clinic for ischemic stroke.

Association between Mapuche Ethnicity and Stroke: A Case-Control Study

BACKGROUND

There is evidence of a greater incidence of stroke in native populations and minorities. A total of 34% of the population in the Araucanía Region is indigenous. The association between Mapuche ethnicity and stroke is unknown. The aim of the study was to estimate the magnitude of the association between Mapuche ethnicity and stroke occurrence in patients admitted to the Dr. Hernán Henríquez Aravena Hospital (HHHA) in Temuco, Chile.

METHODS

We performed an incident case-control-paired study with patients hospitalized with an acute stroke in the internal medicine service and controls from other medical services at the HHHA. One control was selected for each case, matched by gender and age (±5 years).

RESULTS

A total of 104 nonconsecutive cases of stroke were included. The proportion of Mapuche individuals was similar between cases and controls (27.9% and 32.7%, respectively, P = .45). Hypertension and overweight-obesity were associated with stroke. Low socioeconomic status, rurality, diabetes, and smoking were associated with Mapuche ethnicity. In the conditional logistic regression model, Mapuche ethnicity was not associated with stroke. The odds ratio was .75 (P = .47, 95% confidence intervals: .35-1.62).

CONCLUSIONS

There is no statistically significant evidence in the study to support the hypothesis of an association between Mapuche ethnicity and stroke. None of the control variables modified the effect of ethnicity on stroke.

What can ecological studies tell us about death?

Using an ecological study design, Gordon et al. (Isr J Health Policy Res 6:39, 2017) demonstrate variations in mortality patterns across districts and sub-districts of Israel during 2008-2013. Unlike other epidemiological study designs, the units of analysis in ecological studies are groups of people, often defined geographically, and the exposures and outcomes are aggregated, and often known only at the population-level. The ecologic study has several appealing characteristics (such as reliance on public-domain anonymous data) alongside a number of important potential limitations including the often mentioned 'ecological fallacy'. Advantages and disadvantages of the ecological design are described briefly below.

Georeferencing deaths from stroke in São Paulo: an intra-city stroke belt?

Background

The role of socioeconomic status in the worldwide stroke burden has been studied with various methods using vital statistics and research-generated data.

Aim

The objective of our study was to describe the stroke mortality rates and the stroke mortality distribution, and to evaluate the association between stroke mortality rates and geographical distribution with the human development index in São Paulo, Brazil.

Methods

This ecological study evaluated a historical series of stroke mortality in São Paulo, Brazil, from 2004 to 2010. Standard stroke mortality rate per 100 000 inhabitants at each year, the address of residence assumed as the place of living, and the human development index applied as a social indicator were used in order to evaluate if stroke mortality correlated with socioeconomic status.

Results

The mean standardized stroke mortality in São Paulo decreased from 66 to 46-7 per 100 000 inhabitants from 2004 to 2010. Stroke mortality differed according to human development index strata with an almost three times higher stroke mortality in the lowest when compared with the highest human development index stratum. Visual inspection of the map of the districts with high stroke mortality disclosed regional clusters with high mortality in the east, northwest, and south regions, a finding suggestive of the presence of a stroke belt inside the city of São Paulo.

Conclusions

In conclusion, between 2004 and 2010, stroke mortality rates decreased by 28-5% in São Paulo. A geographical pattern in stroke mortality could be observed, with considerable differences according the human development index level of the place of living.

Aneurismal subarachnoid hemorrhage in a Chilean population, with emphasis on risk factors

Background

Subarachnoid Hemorrhage (SAH) is caused principally by the rupture of intracranial aneurisms. Important risk factors have been described such as age, sex, hypertension (HT) and season of the year, among others. The objective is to investigate the demographic characteristics and possible risk factors in a population of Chilean patients.

Methods

This retrospective study was based on the analysis of 244 clinical records of patients diagnosed with aneurismal SAH who were discharged from the Instituto de Neurocirugía ASENJO in Santiago, Chile.

Results

The mean age of patients was 49.85 years and the male:female ratio was 1:2.7. The signs and symptoms were not different between sexes; cephalea (85.7%) was predominant, followed by loss of consciousness, vomiting/nausea and meningeal signs. Risk factors included sex, age and HT. Concordant with other reports, the incidence of SAH was greatest in spring.

Conclusions

The demographic characteristics and risk factors observed in patients with aneurismal SAH treated in ASENJO were comparable to those of other populations. We were not able to conclude that tobacco and alcohol consumption were risk factors for this population.