An epidemiological study of stroke hospitalizations in Maputo, Mozambique: a high burden of disease in a resource-poor country

Model-based patterns of cardiovascular risk factors in Mozambique

BACKGROUND

Risk factors for cardiovascular diseases tend to cluster, although evidence from settings under epidemiological transition is scarce.

AIM

To identify patterns of clustering of cardiovascular risk factors and to quantify their association with sociodemographic characteristics, in Mozambique.

SUBJECTS AND METHODS

A national representative sample (n = 3323) of subjects aged 25-64 years was evaluated in 2005, using the World Health Organization Stepwise Approach to Chronic Disease Risk Factor Surveillance (STEPS). Patterns of joint exposure to high blood pressure, high fasting blood glucose, high body mass index, smoking, excessive alcohol consumption, low fruit/vegetables intake and insufficient physical activity were identified through latent class analysis.

RESULTS

Three patterns were identified among women: (1) "healthier", lower frequency of most risk factors (53.0%); (2) "hypertension-overweight" (21.1%), more frequent among older and urban subjects; and (3) "hypertension-smoking-alcohol" (25.9%), whose frequency increased with age and decreased with education. In men, two clusters were identified: (1) "hypertension-overweight" (30.1%); and (2) "smoking" (69.9%). The frequency of the latter pattern was higher in urban areas and increased with age and education.

CONCLUSION

Hypertension, overweight/obesity, smoking and excessive alcohol intake defined the main clusters of cardiovascular risk factors. This should be considered when planning prevention and control strategies for cardiovascular diseases in Mozambique.

An estimate of the incidence and prevalence of stroke in Africa: a systematic review and meta-analysis

BACKGROUND

Stroke is increasingly becoming a challenging public health issue in Africa, and the non-availability of data has limited research output and consequently the response to this burden. This study aimed to estimate the incidence and prevalence of stroke in Africa in 2009 towards improved policy response and management of the disease in the region.

METHODS

A systematic search of Medline, EMBASE and Global Health for original population-based or hospital-based studies on stroke was conducted. A random effect meta-analysis was conducted on crude stroke incidence and prevalence rates, and a meta-regression-like epidemiological model was applied on all data points. The fitted curve generated from the model was used to estimate incident cases of stroke and number of stroke survivors in Africa at midpoints of the United Nation population 5-year age groups for the year 2009.

RESULTS

The literature search yielded a total of 1227 studies. 19 studies from 10 African countries were selected. 483 thousand new stroke cases among people aged 15 years or more were estimated in Africa in 2009, equivalent to 81.2 (13.2-94.9)/100,000 person years. A total of 1.89 million stroke survivors among people aged 15 years or more were estimated in Africa in 2009, with a prevalence of 317.3 (314.0-748.2)/100,000 population. Comparable figures for the year 2013 based on the same rates would amount to 535 thousand (87.0-625.3) new stroke cases and 2.09 million (2.06-4.93) stroke survivors, suggesting an increase of 10.8% and 9.6% of incident stroke cases and stroke survivors respectively, attributable to population growth and ageing between 2009 and 2013.

CONCLUSION

The findings of this review suggest the burden of stroke in Africa is high and still increasing. There is need for more research on stroke and other vascular risk factors towards instituting appropriate policy, and effective preventive and management measures.

Cardiovascular risk in Mozambique: who should be treated for hypertension?

AIM

To estimate the proportion of Mozambicans eligible for pharmacological treatment for hypertension, according to single risk factor and total cardiovascular risk approaches.

METHODS

A representative sample of Mozambicans aged 40-64 years (n=1116) was evaluated according to the WHO STEPwise Approach to Chronic Disease Risk Factor Surveillance (STEPS). We measured blood pressure (BP) and 12-h fasting blood glucose levels and collected data on sociodemographic characteristics, smoking, and use of antidiabetic and antihypertensive drugs. We estimated the 10-year risk of a fatal or nonfatal major cardiovascular event (WHO/International Society of Hypertension risk prediction charts), and computed the proportion of untreated participants eligible for pharmacological treatment for hypertension, according to BP values alone and accounting also for the total cardiovascular risk (WHO guidelines for assessment and management of cardiovascular diseases).

RESULTS

Among the Mozambicans aged 40-64 years and not taking antihypertensive drugs, less than 4% were classified as having cardiovascular risk at least 20% whereas the prevalence of SBP/DBP at least 140/90 mmHg was nearly 40%. A total of 19.8% of 40-64-year-olds would be eligible for pharmacological treatment of hypertension according to the WHO guidelines, all of whom had SBP/DBP at least 160/100 mmHg.

CONCLUSION

Among the Mozambicans aged 40-64 years not taking antihypertensive drugs and having SBP/DBP at least 140/90 mmHg, only half were eligible for pharmacological treatment according to the WHO guidelines. Taking the latter into account, when defining strategies to control hypertension at a population level, may allow a more efficient use of the scarce resources available in developing settings.

The incidence, hospital expenditure, and, 30 day and 1 year mortality rates of spontaneous intracerebral hemorrhage in Taiwan

The risks of morbidity and mortality are high in patients with spontaneous intracerebral hemorrhage (sICH). The medical care resources associated with sICH are also substantial. This study aimed to evaluate the medical expenditure for sICH patients in Taiwan. We analyzed the National Health Insurance Research Database from 2005 to 2010. The inclusion criterion was first-event sICH; traumatic ICH patients were excluded. Student's t-test, multiple linear regression and the chi-squared test were employed as the statistical methods. Our results showed that the incidence of sICH was 40.77 patients per 100,000 of population per year in Taiwan. The incidence increased with age and was greater in men than women. The mean hospital length of stay (LOS) of first-event sICH patients was 31.8 days; the mean LOS in the intensive care unit was 7.9 days; and the mean survival time was 60.4 months. The mortality rate within 30 days and within 1 year was 19.8 and 29.6%, respectively. The mean hospital expenditure of first-event sICH patients was USD $7572, and was highly correlated with LOS. In conclusion, the incidence of sICH in Taiwan is higher than that in white and black populations of northern America and some European countries and lower than that in the Asian populations of Japan and China. The features of male and female sICH patients differ. Our findings suggest that the hospital expenditure and mortality rate of sICH patients in Taiwan are comparable with those of other countries.

Recent advances in the epidemiology, outcome, and prevention of myocardial infarction and stroke in sub-Saharan Africa

The early part of the new millennium witnessed reports of a growing burden of cardiovascular disease in Sub-Saharan Africa (SSA). However the contribution of ischemic heart disease and stroke to this increasing burden relative to that caused by hypertensive heart disease, cardiomyopathy and rheumatic heart disease was not clear. Over the last decade, data from the continent has begun to clarify this issue and suggests three main points. The burden of ischemic heart disease relative to other causes of heart disease remains low particularly in the black Africans majority. Stroke caused predominantly by hypertension is now a major cause of disability and premature death. Third, the burden of risk factors for atherosclerosis is increasing rapidly in most urban and some rural regions. A concerted effort to understand the primary drivers of this increase in cardiac risk factors is required to prevent a future epidemic of atherosclerosis and its sequelae.

The effect of season and temperature variation on hospital admissions for incident stroke events in Maputo, Mozambique

BACKGROUND

Identifying locale-specific patterns regarding the variation in stroke incidence throughout the year and with atmospheric temperature may be useful to the organization of stroke care, especially in low-resource settings.

GOAL

We aimed to describe the variation in the incidence of stroke hospitalizations across seasons and with short-term temperature variation, in Maputo, Mozambique.

METHODS

Between August 1, 2005, and July 31, 2006, we identified 651 stroke events in Maputo dwellers, according to the World Health Organization's STEPwise approach. The day of symptom onset was defined as the index date. We computed crude and adjusted (humidity, precipitation and temperature) incidence rate ratios (IRRs) and 95% confidence intervals (CIs) with Poisson regression.

RESULTS

Stroke incidence did not vary significantly with season (dry versus wet: crude IRR = .98, 95% CI: .84-1.15), atmospheric temperature at the index date, or average atmospheric temperature in the preceding 2 weeks. The incidence rates of stroke were approximately 30% higher when in the previous 10 days there was a decline in the minimum temperature greater than or equal to 3 °C between any 2 consecutive days (variation in minimum temperature -5.1 to -3.0 versus -2.3 to -.4, adjusted IRR = 1.31, 95% CI: 1.09-1.57). No significant associations were observed according to the variation in maximum temperatures.

CONCLUSIONS

Sudden declines in the minimum temperatures were associated with a higher incidence of stroke hospitalizations in Maputo. This provides important information for prediction of periods of higher hospital affluence because of stroke and to understand the mechanisms underlying the triggering of a stroke event.

Determinants of early case-fatality among stroke patients in Maputo, Mozambique and impact of in-hospital complications

The burden of stroke is increasing in developing countries that struggle to manage it efficiently. We identified determinants of early case-fatality among stroke patients in Maputo, Mozambique, to assess the impact of in-hospital complications. Patients admitted to any hospital in Maputo with a new stroke event were prospectively registered (n = 651) according to the World Health Organization's STEPwise approach, in 2005-2006. We assessed the determinants of in-hospital and 28-day fatality, independently of age, gender and education, and computed population attributable fractions. In-hospital mortality was higher among patients with Glasgow score at admission ≤ 6 (more than fivefold) or needing cardiopulmonary resuscitation during hospitalization (approximately 2.5-fold). Pneumonia and deep vein thrombosis/other cardiovascular complications during hospitalization were responsible for 19.6% (95% confidence interval, 5.3 to 31.7) of ischaemic stroke and 15.9% (95% confidence interval, 5.8 to 24.9) of haemorrhagic stroke deaths until the 28th day. Ischaemic stroke patients with systolic blood pressure 160-200 mmHg had lower in-hospital mortality (relative risk = 0.32, 95% confidence interval, 0.13 to 0.78), and, for those with haemorrhagic events (haemorrhagic stroke), 28-day mortality was higher when systolic blood pressure was over 200 mmHg (hazard ratio = 3.42; 95% confidence interval, 1.02 to 11.51), compared with systolic blood pressure 121-140 mmHg. Regarding diastolic blood pressure, the risk was lowest at 121-150 mmHg for ischaemic stroke and at 61-90 mmHg for haemorrhagic stroke. Early case-fatality was mostly influenced by stroke severity and in-hospital complications. The allocation of resources to the latter may have a large impact on the reduction of the burden of stroke in this setting.

Quality of acute ischemic stroke care in Thailand: a prospective multicenter countrywide cohort study

BACKGROUND

Data concerning quality of acute stroke care and outcome are scarce in developing countries.

OBJECTIVE

This study aimed to evaluate quality of acute stroke care and stroke outcomes in Thailand.

METHODS

We performed a multicenter countrywide prospective cohort study. Consecutive patients with an acute ischemic stroke admitted to the participating institutions between June 2008 and November 2010 were included. Baseline characteristics, process measures including thrombolysis use, acute stroke unit admission, initiation of aspirin within 48 hours, and antithrombotic and/or anticoagulation medication at discharge were recorded. Main outcome measures were death and disability at discharge as well as in-hospital complications.

RESULTS

A total of 1222 patients were included with a mean (±SD) age of 65.0 ± 13 years, and 55.0% were men. Median National Institutes of Health Stroke Scale score was 6.5. Patients were given aspirin within 48 hours, admitted to acute stroke unit, and given thrombolytic therapy in 71.1%, 24.6%, and 3.8%, respectively. Good recovery at discharge (modified Rankin scale score 0-1) was found in 26.1%, and 3.2% of patients died during hospitalization. The median length of stay was 4 days. Factors predicting poor outcome (modified Rankin scale score 5-6) at discharge included: age (by 10-year increments: adjusted odds ratio [OR] 1.23; 95% confidence interval [CI], 1.06-1.43), female sex (adjusted OR 1.52; 95% CI, 1.05-2.19), initial National Institutes of Health Stroke Scale score (adjusted OR 1.35; 95% CI, 1.27-1.43), and in-hospital complications (adjusted OR 3.16; 95% CI, 1.58-6.35).

CONCLUSIONS

Limited access to acute ischemic stroke care interventions were observed in many domains especially thrombolysis and stroke unit admission. These findings emphasize an urgent need for strategies to improve standard acute stroke care among developing countries.

Non-communicable diseases in Mozambique: risk factors, burden, response and outcomes to date

Mozambique is located on the East Coast of Africa bordering South Africa, Zimbabwe, Zambia, Malawi and Tanzania and is one of the poorest countries in the world. Currently NCDs account for 28% of deaths in Mozambique. Risk factors such as tobacco and alcohol use and poor diet are present in both urban and rural settings. Diseases such as hypertension and diabetes affect large proportions of the population, but people are often unaware of their condition or poorly managed. Data from studies on diabetes highlight the financial burden for NCD management in Mozambique for both the individual and health system. The National Strategic Plan for the prevention and control of NCDs in Mozambique has as its aim to create a positive environment to minimise or eliminate the exposure to risk factors and guarantee access to care. The plan has as its overall objective to reduce exposure to risk factors and morbidity and mortality due to NCDs and has 4 areas of intervention: 1) Prevention and health education with regards to NCDs; 2) Access to quality care, treatment and follow-up; 3) Prevention of disability and premature mortality and 4) Surveillance, research, monitoring and evaluation and advocacy for NCDs. The Ministry of Health developed projects for diabetes and hypertension and used these as key lessons that could then be applied to other NCDs. Mozambique, through political commitment from the Ministry of Health and the dedication of local champions, has been able to garner international support to improve care for people with diabetes and then use this to develop its National Plan for NCDs. Despite this increase in attention resources available do not match the challenge of NCDs in Mozambique. Mozambique’s experience provides a practical example of actions that can be undertaken in a resource poor country to tackle the emerging burden of NCDs.

Physical activity patterns in Mozambique: urban/rural differences during epidemiological transition

OBJECTIVE

To assess the socio-demographic determinants of physical activity, by intensity and domain, across urban and rural areas in Mozambican adults.

METHOD

A national representative sample (n=3323) of subjects aged 25-64 years was evaluated in 2005 following the World Health Organization (WHO) Stepwise Approach to Chronic Disease Risk Factor Surveillance (STEPS), which includes the Global Physical Activity Questionnaire. We computed prevalences, and age- and education-adjusted prevalence ratios (PR), with 95% confidence intervals (95%CI).

RESULTS

Most of the Mozambicans reported a high physical activity level, according to the WHO criteria (urban women: 83.2%, 95%CI 77.4, 89.0; rural women: 93.2%, 95%CI 89.0, 97.3; urban men: 78.9%, 95%CI 74.7, 83.1; rural men: 91.6%, 95%CI 85.5, 97.6). The prevalences of <75 min/week of vigorous activities were higher in urban settings (women: PR=2.21; men: PR=2.28) and increased with education, regardless of place of residence (PR ranging between 1.75 and 5.72 for more vs. less educated subjects). Work activities were the most important contributor to the overall physical activity, followed by transport.

CONCLUSION

Most of the Mozambicans reported to be physically active. Vigorous activities were less common in urban areas and among the more educated subjects, depicting an ongoing shift to more sedentary behaviours in this setting.

Rationale and design of the Newer Versus Older Antihypertensive Agents in African Hypertensive Patients (NOAAH) trial

BACKGROUND

Sub-Saharan Africa experiences an epidemic surge in hypertension. Studies in African Americans led to the recommendation to initiate antihypertensive treatment in Blacks with a diuretic or a low-dose fixed combination including a diuretic. We mounted the Newer versus Older Antihypertensive Agents in African Hypertensive Patients (NOAAH) trial to compare in native African patients a fixed combination of newer drugs, not involving a diuretic, with a combination of older drugs including a diuretic.

METHODS

Patients aged 30-69 years with uncomplicated hypertension (140-179/90-109 mmHg) and two or fewer associated risk factors are eligible. After a 4-week run-in period off treatment, 180 patients will be randomized to once daily bisoprolol/hydrochlorothiazide 5/6.25 mg or amlodipine/valsartan 5/160 mg. To attain and maintain blood pressure below 140/90 mmHg during 6 months of follow-up, the doses of bisoprolol and amlodipine in the combination tablets will be increased to 10 mg/day with the possible addition of α-methyldopa or hydralazine. NOAAH is powered to demonstrate a 5-mmHg between-group difference in sitting systolic pressure with a two-sided p-value of 0.01 and 90% power. NOAAH is investigator-led and complies with the Helsinki declaration.

RESULTS

Six centers in four sub-Saharan countries started patient recruitment on September 1, 2010. On December 1, 195 patients were screened, 171 were enrolled, and 51 were randomized and followed up. The trial will be completed in the third quarter of 2011.

CONCLUSIONS

NOAAH (NCT01030458) is the first randomized multicenter trial of antihypertensive medications in hypertensive patients born and living in sub-Saharan Africa.

Early and one-year stroke case fatality in Sao Paulo, Brazil: applying the World Health Organization's stroke STEPS

Case fatality rate is considered a main determinant of stroke mortality trends. We applied the World Health Organization's Stroke STEPS to identify case fatality rates in a community hospital in Brazil. We evaluated all patients with first-ever stroke seeking acute care at the hospital's emergency ward between April 2006 and December 2008 to verify early and late case fatality according to stroke subtype. We used years of formal education as a surrogate for socioeconomic status. Of 430 first-ever stroke events, 365 (84.9%) were ischemic and 65 (15.1%) were intracerebral hemorrhage. After 1 year, we adjudicated 108 deaths (86 ischemic; 22 hemorrhagic). Age-adjusted case fatality rates for ischemic stroke and intracerebral hemorrhage were 6.0% v 19.8% at 10 days, 10.6% v 22.1% at 28 days, 17.6% v 29.1% at 6 months, and 21.0% v 31.5% at 1 year. Illiteracy or no formal education was a predictor of death at 6 months (odds ratio [OR], 4.31; 95% confidence interval [CI] 1.34-13.91) and 1 year (OR, 4.21; 95% CI, 1.45-12.28) in patients with ischemic stroke, as well as at 6 months (OR, 3.19; 95% CI, 1.17-8.70) and 1 year (OR, 3.30; 95% CI, 1.30-8.45) for all stroke patients. Other variables, including previous cardiovascular risk factors and acute medical care, did not change this association to a statistically significant degree. In conclusion, case fatality, particularly up to 6 months, was higher in hemorrhagic stroke, and lack of formal education was associated with increased stroke mortality.

Stroke: a realistic approach to a growing problem in sub-Saharan Africa is urgently needed

Stroke is an increasing problem in sub-Saharan Africa, even in children. High rates of hypertension, diabetes, alcohol abuse, smoking, insufficient fruit and vegetable consumption, sickle cell disease, HIV infection, antiretroviral use and race are likely contributing factors. Although often considered as related to increasing wealth, stroke is more strongly related to poverty, and in turn increases it. Case-fatality rates are high and premature death and years of life lost are a major problem. We propose an approach to stroke prevention and treatment that takes into account the real situation on the ground and can be applied in sub-Saharan Africa, an area where stroke units are largely not feasible and many patients do not reach hospitals. Involvement of community and faith-based organisations, use of simple diagnostic tests, emphasis on clinical examination to differentiate between haemorrhagic and ischaemic stroke, prompt initiation of aspirin therapy and training of community nurses on essential management of stroke should be urgently implemented.

Elevated risk factors but low burden of heart disease in urban African primary care patients: a fundamental role for primary prevention

BACKGROUND

Few data describe the case burden of heart disease and cardiovascular risk factors relative to other conditions in urban Africans seeking primary health care.

METHODS

A clinical registry captured data on 1311 consecutive primary care patients (99% African) from two primary care clinics in Soweto, South Africa. Those with suspected sub-clinical heart disease had more advanced cardiologic assessment.

RESULTS

Overall, 862 women (66%, 41 ± 16 years) and 449 men (38 ± 14 years) were studied. Whilst more men were smokers (47% vs. 14%; OR 5.23, 95% CI 4.01-6.82), more women were obese (42% vs. 14%; OR 4.54, 95% CI 3.33-5.88); blood glucose levels doubling with age in obese women. Although 33% were hypertensive, only 4.9% had type 2 diabetes (n=45), heart disease (n=10) and/or cerebrovascular disease (n=12). Overall, 16% (n=205) had an abnormal 12-lead ECG with more men than women showing a major abnormality (24% vs. 11%; OR 2.63, 95% CI 1.89-3.46). Of 99 cases (7.6%) subject to advanced cardiologic assessment, 29 (2.2%) had newly diagnosed heart disease: including hypertensive heart failure (13 women vs. 2 men, OR 4.51 95% CI 1.00-21.2), coronary artery disease (n=3), valve disease (n=3), dilated cardiomyopathy (n=3) and 2 cases of acute myocarditis.

CONCLUSIONS

These data demonstrate a relatively low burden of heart disease in urban African patients seeking primary health care. Alternatively, high antecedent risk, particularly among obese women, highlights a key role for enhanced primary prevention.

Standing at the crossroads between new and historically prevalent heart disease: effects of migration and socio-economic factors in the Heart of Soweto cohort study

AIMS

Migration, urbanization, and change in socio-economic factors have potentially profound effects on heart disease in low-to-middle income countries.

METHODS AND RESULTS

Chris Hani Baragwanath Hospital in Soweto, South Africa, provides health care to >1 million Africans. We systematically captured data from all de novo presentations of suspected heart disease (focusing on 'new' vs. historically prevalent forms) during 2006-2008. There were 3168 female (52 ± 18 years) vs. 2160 male (53 ± 17 years) cases. Overall, 999 (19%) presented with uncomplicated hypertension (n = 988) or type II diabetes, 1862 cases (35%) 'new' heart disease (1146 and 581 cases of hypertensive heart failure and coronary artery disease), and 2092 cases (39%) of historically prevalent heart disease (including 724 with primary valve disease and 502 idiopathic dilated cardiomyopathies). Level of education and non-communicable risk factors were important correlates of advanced disease. The rate of historically prevalent cases was higher in those aged 20-49 years (19-60 cases/100,000 population/annum) whilst being higher for "new" heart disease in those aged >50 years (155-343 cases/population/annum). Historically prevalent heart disease cases were younger [adjusted odds ratio (OR) 0.98, 95% 0.97-0.99 per year], more likely to be African (OR 4.59, 95% 2.76-7.60) while being less likely to originate from Soweto (OR 0.87, 95% 0.75-1.00) and be female (OR 0.67, 95% 0.49-0.92).

CONCLUSION

Dynamic socio-economic and lifestyle factors characteristic of epidemiological transition appear to have positioned the urban, mainly African community of Soweto at the crossroads between historically prevalent and 'new' forms of heart disease.