Olulola O Oladapo

Cardiovascular risk management and its impact on hypertension control in primary care in low-resource settings: a cluster-randomized trial

OBJECTIVE To evaluate a simple cardiovascular risk management package for assessing and managing cardiovascular risk using hypertension as an entry point in primary care facilities in low-resource settings. METHODS Two geographically distant regions in two countries (China and Nigeria) were selected and 10 pairs of primary care facilities in each region were randomly selected and matched. Regions were then randomly assigned to a control group, which received usual care, or to an intervention group, which applied the cardiovascular risk management package. Each facility enrolled 60 consecutive patients with hypertension. Intervention sites educated patients about risk factors at baseline and initiated treatment with hydrochlorothiazide at 4 months in patients at medium risk of a cardiovascular event, according to a standardized treatment algorithm. Systolic blood pressure change from baseline to 12 months was the primary outcome measure. FINDINGS The study included 2397 patients with baseline hypertension: 1191 in 20 intervention facilities and 1206 in 20 control facilities. Systolic and diastolic blood pressure decreased more in intervention patients than in controls. However, at 12 months more than half of patients still had uncontrolled hypertension (systolic blood pressure > 140 mmHg and/or diastolic blood pressure > 90 mmHg). Behavioural risk factors had improved among intervention patients in Nigeria but not in China. Only about 2% of hypertensive patients required referral to the next level of care. CONCLUSION Even in low-resource settings, hypertensive patients can be effectively assessed and managed in primary care facilities.

Barriers to management of cardiovascular risk in a low-resource setting using hypertension as an entry point

Objective Assess capacity of health-care facilities in a low-resource setting to implement the absolute risk approach for assessment of cardiovascular risk in hypertensive patients and effective management of hypertension Design and setting A descriptive cross-sectional study in Egbeda and Oluyole local government areas of Oyo State in Nigeria in 56 randomly selected primary- (n = 42) and secondary-level (n = 2) health-care and private health-care (n = 12) facilities. Participants One thousand consecutive, known hypertensives attending the selected facilities for follow-up, and health-care providers working in the above randomly selected facilities, were interviewed. Results About two-thirds of hypertensives utilized primary-care centers both for diagnosis and for follow-up. Laboratory and other investigations to exclude secondary hypertension or to assess target organ damage were not available in the majority of facilities, particularly in primary care. A considerable knowledge and awareness gap related to hypertension and its complications was found, both among patients and health-care providers. Blood pressure control rates were poor [28% with systolic blood pressure (SBP) < 140 mmHg and diastolic blood pressure (DBP) < 90 mmHg] and drug prescription patterns were not evidence based and cost effective. The majority of patients (73%) in this low socio-economic group (mean monthly income US

Left ventricular geometric patterns in newly presenting nigerian hypertensives: An echocardiographic study

73) had to pay fully, out of their own pocket, for consultations and medications. Conclusions If the absolute risk approach for assessment of risk and effective management of hypertension is to be implemented in low-resource settings, appropriate policy measures need to be taken to improve the competency of health-care providers, to provide basic laboratory facilities and to develop affordable financing mechanisms.

Echocardiographic partition values and prevalence of left ventricular hypertrophy in hypertensive Nigerians.

BackgroundHypertension is a global problem and it is prevalent in Nigeria. Left ventricular hypertrophy is a major complication of hypertension with risk of sudden death and arrhythmias among others. Abnormal left ventricular geometric patterns also increase the burden of morbidity and mortality. It is therefore important to know the different left ventricular geometric patterns in Nigerian hypertensives because of their prognostic significance.MethodsOne hundred (100) newly presenting hypertensives (53 males and 47 females) and 100 controls (53 males and 47 females) were recruited for the study. All were subjected to clinical evaluation and full echocardiographic examination was performed according to the ASE recommendation. The relative wall thickness and the presence or absence of echocardiographic left ventricular hypertrophy were used to determine the various geometric patternsResultsThe mean age of the hypertensive subjects was 56.06 (± 7.68) years while that of the control subjects was 56.10 (± 7.68) years. There was no significant difference in the mean ages of the two groups. In the hypertensive subjects 28% had normal geometry, 26% had concentric remodeling, 28% had concentric hypertrophy and 18% had eccentric hypertrophy. In the control group, 86% had normal geometry, 11% had concentric remodeling, 3% had eccentric hypertrophy and none had concentric hypertrophy. There was statistical significance when the geometric patterns of the hypertensive and controls were compared (χ2 = 74.30, p value < 0.0001).ConclusionThe study showed that only 28% of the hypertensive subjects had normal LV geometric pattern while 86% of the normal subjects had normal geometry. There is need for longitudinal studies in order to prognosticate the various geometric patterns.

Target-organ damage and cardiovascular complications in hypertensive Nigerian Yoruba adults: a cross-sectional study.

BackgroundLeft ventricular hypertrophy (LVH) is a well known independent risk factor for cardiovascular events. It has been shown that combination of left ventricular mass (LVM) and relative wall thickness (RWT) can be used to identify different forms of left ventricular (LV) geometry. Prospective studies have shown that LV geometric patterns have prognostic implications, with the worst prognosis associated with concentric hypertrophy. The methods for the normalization or indexation of LVM have also recently been shown to confer some prognostic value especially in obese population. We sought to determine the prevalence of echocardiographic lLVH using eight different and published cut-off or threshold values in hypertensive subjects seen in a developing countrys tertiary centre.MethodsEchocardiography was performed in four hundred and eighty consecutive hypertensive subjects attending the cardiology clinic of the University college Hospital Ibadan, Nigeria over a two-year period.ResultsComplete data was obtained in 457 (95.2%) of the 480 subjects (48.6% women). The prevalence of LVH ranged between 30.9–56.0%. The highest prevalence was when LVM was indexed to the power of 2.7 with a partition value of 49.2 g/ht2.7 in men and 46.7 g/ht2.7 in women. The lowest prevalence was observed when LVM was indexed to body surface area (BSA) and a partition value of 125 g/m2 was used for both sexes. Abnormal LV geometry was present in 61.1%–74.0% of our subjects and commoner in women.ConclusionThe prevalence of LVH hypertensive patients is strongly dependent on the cut-off value used to define it. Large-scale prospective study will be needed to determine the prognostic implications of the different LV geometry in native Africans.

Association between Electrocardiographic Left Ventricular Hypertrophy with Strain Pattern and Left Ventricular Structure and Function

Background Hypertension is a major challenge to public health as it is frequently associated with sudden death due to the silent nature of the condition. By the time of diagnosis, some patients would have developed target-organ damage (TOD) and associated clinical conditions (ACC) due to low levels of detection, treatment and control. TOD and ACC are easy to evaluate in a primary healthcare (PHC) setting and offer valuable information for stratifying cardiovascular risks in the patient. The aim of this study was to evaluate the prevalence and correlates of TOD and established cardiovascular disease (CVD) in hypertensive Nigerian adults. Methods A cross-sectional study was conducted on 2 000 healthy Yoruba adults between 18 and 64 years who lived in a rural community in south-western Nigeria. Participants diagnosed to have hypertension were examined for TOD and ACC by the presence of electrocardiographically determined left ventricular hypertrophy (LVH), microalbuminuria or proteinuria, retinopathy, or history of myocardial infarction and stroke. Results A total of 415 hypertensive participants were examined and of these, 179 (43.1%) had evidence of TOD and 45 (10.8%) had established CVD. TOD was associated with significantly higher systolic (SBP) and diastolic blood pressure (DBP). The prevalence of LVH was 27.9%, atrial fibrillation 16.4%, microalbuminuria 12.3%, proteinuria 15.2%, hypertensive retinopathy 2.2%, stroke 6.3%, congestive heart failure (CHF) 4.6%, ischaemic heart disease 1.7%, and peripheral vascular disease 3.6%. Compared with those with normal blood pressure (BP), the multivariate adjusted odds ratios (95% confidence interval) of developing TOD was 3.61 (0.59–8.73) for those with newly diagnosed hypertension; 4.76 (1.30–13.06) for those with BP ≥ 180/110 mmHg; and 1.85 (0.74–8.59) for those with diabetes mellitus. Conclusions This study provides new data on TOD and its correlates in a nationally representative sample of hypertensive adults in Nigeria. In this low-resource setting, attempts should be made to detect hypertensive patients early within the community and manage them appropriately before irreversible organ damage and complications set in. The methods used in this study are simple and adaptable at the primary healthcare level for planning prevention and intervention programmes.

Knowledge of Hypertension and other Risk Factors for Heart Disease among Yoruba Rural Southwestern Nigerian Population

Background and Purpose: Electrocardiographic left ventricular hypertrophy (LVH) with strain pattern has been documented as a marker for LVH. Its presence on the ECG of hypertensive patients is associated with poor prognosis. The study was carried out to assess the association of the electrocardiographic strain with left ventricular mass (LVM) and function in hypertensive Nigerians. Material and Methods: ECG as well as echocardiograms were performed in 64 hypertensive patients with ECG-LVH and strain pattern, 65 patients with ECG-LVH by Sokolow-Lyon (SL) voltage criteria and 62 normal controls. Results: The study showed that electrocardiographic left ventricular (LV) strain pattern is associated with dilated left atrium, larger LV internal dimensions and greater absolute and indexed LVM in hypertensive Nigerians compared with ECG-LVH by SL voltage criteria alone or normal controls. Conclusion: The findings of this study support the fact that the ECG strain pattern is associated with increased LVM and an increased risk of developing abnormal LV geometry.

Changes in left atrial dimension and function and left ventricular geometry in newly diagnosed untreated hypertensive subjects.

Background and Objectives: There is paucity of reliable information on knowledge about hypertension and cardiovascular disease (CVD) risk factors in rural southwestern Nigeria. This study assessed the level of awareness, basic knowledge and management of hypertension and CV risk factors among people living in rural south western Nigeria. Methods: A population based cross-sectional survey was conducted in Egbeda local government area of Oyo State, Nigeria. A str uctured questionnaire was used to interview 2000 subjects in order to assess knowledge of various aspects of modifiable CV risk factors.

Characterisation of heart failure with normal ejection fraction in a tertiary hospital in Nigeria

Background It is known that a spectrum of changes in structure, size and function of the different chambers of the heart occur in individuals with hypertension. The earliest changes and the sequence of these changes are still being studied. Aims The present study aimed to assess early changes in the left atrial size and function in hypertension, and its relationship with left ventricular geometry and other factors that may influence left atrial size. Methods One hundred consecutive subjects who were newly diagnosed with hypertension and 50 apparently normal individuals were recruited into the study. Standard M-mode, two-dimensional and Doppler echocardiography were performed. The endocardial border of the left atrium was traced to obtain the atrial area and left atrial volumes and emptying fractions were derived from measured areas. Results The hypertensive patients and the controls were comparable by age, sex and body mass index. Thirty-seven (37%) of the hypertensive subject had increased left ventricular mass versus eight subjects (16%) in the normal controls. The patients with hypertension had a higher linear left atrial dimension (3.5 ± 0.48 cm versus 3.1 ± 0.47 cm, P < 0.0001), longer pre-atrial contraction length (3.8 ± 0.56 cm versus 3.6 ± 0.45 cm; P = 0.02) and higher peak late mitral inflow velocity (0.64 ± 0.19 m/s versus 0.56 ± 0.15 m/s; P = 0.010). Conclusions Changes in the geometry of the left ventricle occur early in hypertension and precede deterioration in left ventricular systolic function. The corresponding left atrial changes are marginal and are indicative of increased left atrial length and accentuated atrial systolic function.

Prevalence and severity of atherosclerosis in extra cranial carotid arteries in Nigeria: an autopsy study

BackgroundThe study aimed to determine the frequency and characteristics of heart failure with normal EF in a native African population with heart failure.MethodsIt was a hospital cohort study. Subjects were 177 consecutive individuals with heart failure and ninety apparently normal control subjects. All the subjects underwent transthoracic echocardiography. The group with heart failure was further subdivided into heart failure with normal EF (EF ≥ 50) (HFNEF) and heart failure with low EF(EF <50)(HFLEF).ResultsThe subjects with heart failure have a mean age of 52.3 ± 16.64 years vs 52.1 ± 11.84 years in the control subjects; p = 0.914. Other baseline characteristics except blood pressure parameters and height were comparable between the group with heart failure and the control subjects. The frequency of HFNEF was 39.5%. Compared with the HFLEF group, the HFNEF group have a smaller left ventricular diameter (in diastole and systole): (5.2 ± 1.22 cm vs 6.2 ± 1.39 cm; p < 0.0001 and 3.6 ± 1.24 cm vs 5.4 ± 1.35 cm;p < 0.0001) respectively, a higher relative wall thickness and deceleration time of the early mitral inflow velocity: (0.4 ± 0.12 vs 0.3 ± 0.14 p < 0.0001 and 149.6 ± 72.35 vs 110.9 ± 63.40 p = 0.001) respectively.The two groups with heart failure differed significantly from the control subjects in virtually all echocardiographic measurements except aortic root diameter, LV posterior wall thickness(HFLEF), and late mitral inflow velocity(HFNEF). HFNEF accounted for 70(39.5%) of cases of heart failure in this study.Hypertension is the underlying cardiovascular disease in 134(75.7%) of the combined heart failure population, 58 (82.9%) of the subjects with HFNEF group and 76(71%) of the HFLEF group. Females accounted for 44 (62.9%) of the subjects with HFNEF against 42(39.3%) in the HFLEF group (p = 0.002).ConclusionThe frequency of heart failure with normal EF in this native African cohort with heart failure is comparable with the frequency in other populations. These groups of patients are more likely female, hypertensive with concentric pattern of left ventricular hypertrophy.