Differential associations between pre-diabetes, diabetes and stroke occurrence among West Africans.

BACKGROUND: There are limited data from Africa on the burden and associations between pre-diabetes (pre-DM), diabetes mellitus (DM) and stroke occurrence in a region experiencing a profound rise in stroke burden. PURPOSE: To characterize the associations between stroke and dysglycemic status among West Africans. METHODS: The Stroke Investigative Research and Educational Network (SIREN) is a multicenter, case-control study involving 15 sites in Ghana and Nigeria. Cases include adults aged ≥18 years with clinical and radiological evidence of an acute stroke. Controls were age-and-gender matched stroke-free adults. Detailed evaluations for vascular factors were performed. Pre-diabetes was defined as HBA1c of 5.7%-6.4% or Fasting blood glucose (FBG) 5.6-7.0 mmol/L and DM as HBA1c >6.5% or FBG>7.0 mmol/L. We used conditional logistic regression to estimate adjusted odds ratios (aOR) with 95% Confidence Interval. RESULTS: Among 2,935 stroke cases the mean age was 60.0 ± 14.2 years with 55.2% being males. By glycemic status, 931 (31.7%) were euglycemic, 633 (21.6%) had Pre-diabetes and 1371 (46.7%) had DM. Of the age- and sex-matched stroke-free controls 69.2% were euglycemic, 13.3% had pre-DM and 17.5% had DM. Pre-DM [aOR (95% CI): 3.68(2.61-5.21)] and DM [4.29 (3.19-5.74)] were independently associated with stroke. The aOR of Pre-DM for ischemic stroke 3.06 (2.01-4.64)] was lower than 4.82 (3.37-6.89) for DM. However, the aOR of Pre-DM for hemorrhagic stroke 6.81 (95% CI: 3.29 - 14.08)] was higher than 3.36 (1.94-5.86) for DM. Furthermore, the aOR of pre-DM for ischemic stroke subtypes were 9.64 (1.30-71.57) for cardio-embolic stroke, 3.64 (1.80-7.34) for small-vessel occlusive disease and 4.63 (0.80-26.65) for large-vessel disease. CONCLUSION: Pre-DM is strongly and independently associated with stroke in Africans. Improving glycemic control through screening, healthy lifestyle and pharmacotherapy at a population level may be strategic in reducing the rising burden of stroke in Africa.

Factors associated with hypertension among stroke-free indigenous Africans: Findings from the SIREN study.

Hypertension is one of the most important risk factors for stroke and cardiovascular diseases (CVD) globally. Understanding risk factors for hypertension among individuals with matching characteristics with stroke patients may inform primordial/primary prevention of hypertension and stroke among them. This study identified the risk factors for hypertension among community-dwelling stroke-free population in Ghana and Nigeria. Data for 4267 community-dwelling stroke-free controls subjects in the Stroke Investigative Research and Education Network (SIREN) study in Nigeria and Ghana were used. Participants were comprehensively assessed for sociodemographic, lifestyle and metabolic factors using standard methods. Hypertension was defined as a previous diagnosis by a health professional or use of an anti-hypertensive drug or mean systolic blood pressure ≥ 140 mmHg and/or diastolic blood pressure ≥ 90 mmHg. Logistic regression analysis was used to estimate adjusted odds ratios (aOR) of hypertension and their 95% confidence intervals (CI) at p < .05. Overall, 56.7% of the participants were hypertensive with a higher proportion among respondents aged ≥60 years (53.0%). Factors including physical inactivity (aOR: 9.09; 95% CI: 4.03 to 20.53, p < .0001), diabetes (aOR: 2.70; CI: 1.91 to 3.82, p < .0001), being ≥60 years (aOR: 2.22; 95% CI: 1.78 to 2.77, p < .0001), and family history of CVD (aOR 2.02; CI: 1.59 to 2.56, p < .0001) were associated with increased aOR of hypertension. Lifestyle factors were associated with hypertension in the current population of community-dwelling stroke-free controls in west Africa. Community-oriented interventions to address sedentary lifestyles may benefit this population and reduce/prevent hypertension and stroke among them.

Monitoring and evaluation framework for hypertension programs. A collaboration between the Pan American Health Organization and World Hypertension League.

The Pan American Health Organization (PAHO)-World Hypertension League (WHL) Hypertension Monitoring and Evaluation Framework is summarized. Standardized indicators are provided for monitoring and evaluating national or subnational hypertension control programs. Five core indicators from the World Health Organization hearts initiative and a single PAHO-WHL core indicator are recommended to be used in all hypertension control programs. In addition, hypertension control programs are encouraged to select from 14 optional qualitative and 33 quantitative indicators to facilitate progress towards enhanced hypertension control. The intention is for hypertension programs to select quantitative indicators based on the current surveillance mechanisms that are available and what is feasible and to use the framework process indicators as a guide to program management. Programs may wish to increase or refine the number of indicators they use over time. With adaption the indicators can also be implemented at a community or clinic level. The standardized indicators are being pilot tested in Cuba, Colombia, Chile, and Barbados.

Exploring Overlaps Between the Genomic and Environmental Determinants of LVH and Stroke: A Multicenter Study in West Africa.

BACKGROUND: Whether left ventricular hypertrophy (LVH) is determined by similar genomic and environmental risk factors with stroke, or is simply an intermediate stroke marker, is unknown. OBJECTIVES: We present a research plan and preliminary findings to explore the overlap in the genomic and environmental determinants of LVH and stroke among Africans participating in the SIREN (Stroke Investigative Research and Education Network) study. METHODS: SIREN is a transnational, multicenter study involving acute stroke patients and age-, ethnicity-, and sex-matched control subjects recruited from 9 sites in Ghana and Nigeria. Genomic and environmental risk factors and other relevant phenotypes for stroke and LVH are being collected and compared using standard techniques. RESULTS: This preliminary analysis included only 725 stroke patients (mean age 59.1 ± 13.2 years; 54.3% male). Fifty-five percent of the stroke subjects had LVH with greater proportion among women (51.6% vs. 48.4%; p < 0.001). Those with LVH were younger (57.9 ± 12.8 vs. 60.6 ± 13.4; p = 0.006) and had higher mean systolic and diastolic blood pressure (167.1/99.5 mm Hg vs 151.7/90.6 mm Hg; p < 0.001). Uncontrolled blood pressure at presentation was prevalent in subjects with LVH (76.2% vs. 57.7%; p < 0.001). Significant independent predictors of LVH were age <45 years (adjusted odds ratio [AOR]: 1.91; 95% confidence interval [CI]: 1.14 to 3.19), female sex (AOR: 2.01; 95% CI: 1.44 to 2.81), and diastolic blood pressure > 90 mm Hg (AOR: 2.10; 95% CI: 1.39 to 3.19; p < 0.001). CONCLUSIONS: The prevalence of LVH was high among stroke patients especially the younger ones, suggesting a genetic component to LVH. Hypertension was a major modifiable risk factor for stroke as well as LVH. It is envisaged that the SIREN project will elucidate polygenic overlap (if present) between LVH and stroke among Africans, thereby defining the role of LVH as a putative intermediate cardiovascular phenotype and therapeutic target to inform interventions to reduce stroke risk in populations of African ancestry.

Transcranial doppler re-screening of subjects who participated in STOP and STOP II.

In children with Sickle Cell Disease, the combination of risk stratification with Transcranial Doppler Ultrasound (TCD) and selective chronic red cell transfusion (CRCT-the STOP Protocol) is one of the most effective stroke prevention strategies in medicine. How fully it is being implemented is unclear. Nineteen of 26 sites that conducted the two pivotal clinical trials (STOP and STOP II) participated in Post STOP, a comprehensive medical records review assessing protocol implementation in the 10-15 years since the trials ended. Professional abstractors identified medical records in the Post STOP era in 2851 (74%) of the 3,840 children who took part in STOP and/or STOP II, and documented TCD rescreening, maintenance of CRCT in those at risk, and stroke. Among 1,896 children eligible for TCD rescreening (target group), evidence of any rescreening was found in 1,090 (57%). There was wide site variation in TCD rescreening ranging from 18% to 91% of eligible children. Both younger age and having a conditional TCD during STOP/II were associated with a higher likelihood of having a TCD in Post STOP. Sixty eight new abnormal, high risk cases were identified. Despite clear evidence of benefit the STOP protocol is not fully implemented even at experienced sites. Site variation suggests that system improvements might remove barriers to implementation and result in even greater reduction of ischemic stroke in children with SCD. Am. J. Hematol. 91:1191-1194, 2016. © 2016 Wiley Periodicals, Inc.

Multilingual Validation of the Questionnaire for Verifying Stroke-Free Status in West Africa.

BACKGROUND AND PURPOSE: The Questionnaire for Verifying Stroke-Free Status (QVSFS), a method for verifying stroke-free status in participants of clinical, epidemiological, and genetic studies, has not been validated in low-income settings where populations have limited knowledge of stroke symptoms. We aimed to validate QVSFS in 3 languages, Yoruba, Hausa and Akan, for ascertainment of stroke-free status of control subjects enrolled in an on-going stroke epidemiological study in West Africa. METHODS: Data were collected using a cross-sectional study design where 384 participants were consecutively recruited from neurology and general medicine clinics of 5 tertiary referral hospitals in Nigeria and Ghana. Ascertainment of stroke status was by neurologists using structured neurological examination, review of case records, and neuroimaging (gold standard). Relative performance of QVSFS without and with pictures of stroke symptoms (pictograms) was assessed using sensitivity, specificity, positive predictive value, and negative predictive value. RESULTS: The overall median age of the study participants was 54 years and 48.4% were males. Of 165 stroke cases identified by gold standard, 98% were determined to have had stroke, whereas of 219 without stroke 87% were determined to be stroke-free by QVSFS. Negative predictive value of the QVSFS across the 3 languages was 0.97 (range, 0.93-1.00), sensitivity, specificity, and positive predictive value were 0.98, 0.82, and 0.80, respectively. Agreement between the questionnaire with and without the pictogram was excellent/strong with Cohen k=0.92. CONCLUSIONS: QVSFS is a valid tool for verifying stroke-free status across culturally diverse populations in West Africa.

Phenotyping Stroke in Sub-Saharan Africa: Stroke Investigative Research and Education Network (SIREN) Phenomics Protocol.

BACKGROUND: As the second leading cause of death and the leading cause of adult-onset disability, stroke is a major public health concern particularly pertinent in Sub-Saharan Africa (SSA), where nearly 80% of all global stroke mortalities occur, and stroke burden is projected to increase in the coming decades. However, traditional and emerging risk factors for stroke in SSA have not been well characterized, thus limiting efforts at curbing its devastating toll. The Stroke Investigative Research and Education Network (SIREN) project is aimed at comprehensively evaluating the key environmental and genomic risk factors for stroke (and its subtypes) in SSA while simultaneously building capacities in phenomics, biobanking, genomics, biostatistics, and bioinformatics for brain research. METHODS: SIREN is a transnational, multicentre, hospital and community-based study involving 3,000 cases and 3,000 controls recruited from 8 sites in Ghana and Nigeria. Cases will be hospital-based patients with first stroke within 10 days of onset in whom neurovascular imaging will be performed. Etiological and topographical stroke subtypes will be documented for all cases. Controls will be hospital- and community-based participants, matched to cases on the basis of gender, ethnicity, and age (±5 years). Information will be collected on known and proposed emerging risk factors for stroke. STUDY SIGNIFICANCE: SIREN is the largest study of stroke in Africa to date. It is anticipated that it will shed light on the phenotypic characteristics and risk factors of stroke and ultimately provide evidence base for strategic interventions to curtail the burgeoning burden of stroke on the sub-continent.

Racial/Ethnic differences in poststroke rehabilitation outcomes.

Background. Significant racial and ethnic disparities in stroke incidence, severity, and morbidity have been consistently reported; however, less is known about potential differences in poststroke rehabilitation outcomes. Objective. To examine racial and ethnic differences in poststroke rehabilitation outcomes. Methods. We completed an in-depth search of Medline and several major journals dedicated to publishing research articles on stroke, rehabilitation, and racial-ethnic patterns of disease over a 10-year period (2003-2012). We identified studies that reported rehabilitation outcomes and the race or ethnicity of at least two groups. Results. 17 studies involving 429,108 stroke survivors met inclusion criteria for the review. The majority (94%) of studies examined outcomes between Blacks and Whites. Of those studies examining outcomes between Blacks and Whites, 59% showed that Blacks were generally less likely to achieve equivalent functional improvement following rehabilitation. Blacks were more likely to experience lower FIM gain or change scores (range: 1-60%) and more likely to have lower efficiency scores (range: 5-16%) than Whites. Conclusions. Black stroke survivors appear to generally achieve poorer functional outcomes than White stroke survivors. Future studies are warranted to evaluate the precise magnitude of these differences, whether they go beyond chance, and the underlying contributory mechanisms.

Prehypertension, racial prevalence and its association with risk factors: Analysis of the REasons for Geographic And Racial Differences in Stroke (REGARDS) study.

BACKGROUND: There are few available data on the epidemiology of prehypertension (preHTN). To determine racial, clinical, and demographic differences in the prevalence of preHTN and its cross-sectional association with vascular risk factors. METHODS: Cross-sectional analysis of 5,553 prehypertensives, 20,351 hypertensive's, and 4,246 nonhypertensive participants (age ≥45), from a population-based national cohort study (REasons for Geographic And Racial Differences in Stroke (REGARDS) total population 30,239, of whom 30,150 had adequate blood pressure (BP) measurements) enrolled from January 2003-October 2007 with oversampling from the southeastern stroke belt, and black individuals. Baseline data were collected using a combination of telephone interview and in-home evaluation. preHTN was defined according to The Seventh Report of the Joint national Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) guidelines. RESULTS: The prevalence of preHTN was associated with age and black race (62.9% in blacks compared to 54.1% in whites). A higher prevalence of preHTN was observed in obese individuals, self-reported heart disease; and, those with elevated high-sensitivity C reactive protein (hsCRP), diabetes, and microalbuminuria compared to those without these factors. Heavy alcohol consumption in white participants was associated with increased odds of preHTN (odds ratio (OR) = 1.32) but was even greater in black participants (OR = 2.27). CONCLUSION: The prevalence of preHTN increased by age and African-American race. In addition, a higher prevalence of preHTN was observed with elevated hsCRP, diabetes, microalbuminuria, and those with heavy alcohol consumption compared to those without these factors.

Addressing the global cardiovascular risk of hypertension, dyslipidemia, diabetes mellitus, and the metabolic syndrome in the southeastern United States, part II: treatment recommendations for management of the global cardiovascular risk of hypertension, dyslipidemia, diabetes mellitus, and the metabolic syndrome.

An aggressive global approach to screening and to the management of the metabolic syndrome is recommended to slow the growth of the syndrome throughout the United States. Prevention should begin in childhood with healthy nutrition, daily physical activity, and annual measurement of weight, height, and blood pressure beginning at 3 years of age. Such screenings will identify cardiovascular risk factors early, allow the health care provider to define global cardiovascular risk with the COSEHC Cardiovascular Risk Assessment Tool, and allow treatment of each risk factor. Lifelong lifestyle modifications and pharmacologic therapy will be required in most patients. Antihypertensive therapy for these patients should begin with an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker unless a compelling indication for another drug is present. Metformin should be considered the first drug for glucose control in the patient with type 2 diabetes. A statin should be used initially for hyperlipidemia unless contraindicated. Combinations of antihypertensive, antiglycemic, and lipid-lowering agents will often be required.