Effect of 3, 2-Drug Combinations of Antihypertensive Therapies on Blood Pressure Variability in Black African Patients: Secondary Analyses of the CREOLE Trial.

BACKGROUND: The effect of 3 commonly recommended combinations of anti-hypertensive agents-amlodipine plus hydrochlorothiazide (calcium channel blocker [CCB]+thiazide), amlodipine plus perindopril (CCB+ACE [angiotensin-converting enzyme]-inhibitor), and perindopril plus hydrochlorothiazide (ACE-inhibitor+thiazide) on blood pressure variability (V) are unknown. METHODS: We calculated the blood pressure variability (BPV) in 405 patients (130, 146, and 129 randomized to ACE-inhibitor+thiazide, CCB+thiazide, and CCB+ACE-inhibitor, respectively) who underwent ambulatory blood pressure monitoring after 6 months of treatment in the Comparisons of Three Combinations Therapies in Lowering Blood Pressure in Black Africans trial (CREOLE) of Black African patients. BPV was calculated using the SD of 30-minute interval values for 24-hour ambulatory BPs and for confirmation using the coefficient of variation. Linear mixed model regression was used to calculate mean differences in BPV between treatment arms. Within-clinic BPV was also calculated from the mean SD and coefficient of variation of 3 readings at clinic visits. RESULTS: Baseline distributions of age, sex, and blood pressure parameters were similar across treatment groups. Participants were predominately male (62.2%) with mean age 50.4 years. Those taking CCB+thiazide had significantly reduced ambulatory systolic and diastolic BPV compared with those taking ACE-inhibitor+thiazide. The CCB+thiazide and CCB+ACE-inhibitor groups showed similar BPV. Similar patterns of BPV were apparent among groups using within-clinic blood pressures and when assessed by coefficient of variation. CONCLUSIONS: Compared with CCB-containing combinations, ACE-inhibitor plus thiazide was associated with higher levels, generally significant, of ambulatory and within-clinic systolic and diastolic BPV. These results supplement the differential ambulatory blood pressure-lowering effects of these therapies in the CREOLE trial.

Disparities in clinical features and outcomes of peripartum cardiomyopathy in high versus low prevalent regions in Nigeria.

AIMS: The prospective, multicentre Peripartum Cardiomyopathy in Nigeria (PEACE) registry originally demonstrated a high prevalence of peripartum cardiomyopathy (PPCM) among patients originating from Kano, North-West Nigeria. In a post hoc analysis, we sought to determine if this phenomenon was characterized by a differential case profile and outcome among PPCM cases originating elsewhere. METHODS AND RESULTS: Overall, 199 (81.6%) of a total 244 PPCM patients were recruited from three sites in Kano, compared with 45 patients (18.4%) from 11 widely dispersed centres across Nigeria. Presence and extent of ventricular myocardial remodelling during follow-up, relative to baseline status, were assessed by echocardiography. During median 17 months follow-up, Kano patients demonstrated significantly better myocardial reverse remodelling than patients from other sites. Overall, 50.6% of patients from Kano versus 28.6% from other regions were asymptomatic (P = 0.029) at study completion, with an accompanying difference in all-cause mortality (17.6% vs. 22.2% respectively, P = 0.523) not reaching statistical significance. Alternatively, 135/191 (84.9%) of Kano patients had selenium deficiency (<70 µg/L), and 46/135 (34.1%) of them received oral selenium supplementation. Critically, those that received selenium supplementation demonstrated better survival (6.5% vs. 21.2%; P = 0.025), but the supplement did not have significant impact on myocardial remodelling. CONCLUSIONS: This study has shown important non-racial regional disparities in the clinical features and outcomes of PPCM patients in Nigeria, that might partly be explained by selenium supplementation.

The INVICTUS rheumatic heart disease research program: Rationale, design and baseline characteristics of a randomized trial of rivaroxaban compared to vitamin K antagonists in rheumatic valvular disease and atrial fibrillation.

BACKGROUND: Rheumatic heart disease (RHD) is a neglected disease affecting 33 million people, mainly in low and middle income countries. Yet very few large trials or registries have been conducted in this population. The INVICTUS program of research in RHD consists of a randomized-controlled trial (RCT) of 4500 patients comparing rivaroxaban with vitamin K antagonists (VKA) in patients with RHD and atrial fibrillation (AF), a registry of 17,000 patients to document the contemporary clinical course of patients with RHD, including a focused sub-study on pregnant women with RHD within the registry. This paper describes the rationale, design, organization and baseline characteristics of the RCT and a summary of the design of the registry and its sub-study. Patients with RHD and AF are considered to be at high risk of embolic strokes, and oral anticoagulation with VKAs is recommended for stroke prevention. But the quality of anticoagulation with VKA is poor in developing countries. A drug which does not require monitoring, and which is safe and effective for preventing stroke in patients with valvular AF, would fulfill a major unmet need. METHODS: The INVestIgation of rheumatiC AF Treatment Using VKAs, rivaroxaban or aspirin Studies (INVICTUS-VKA) trial is an international, multicentre, randomized, open-label, parallel group trial, testing whether rivaroxaban 20 mg given once daily is non-inferior (or superior) to VKA in patients with RHD, AF, and an elevated risk of stroke (mitral stenosis with valve area ≤2 cm2, left atrial spontaneous echo-contrast or thrombus, or a CHA2DS2VASc score ≥2). The primary efficacy outcome is a composite of stroke or systemic embolism and the primary safety outcome is the occurrence of major bleeding. The trial has enrolled 4565 patients from 138 sites in 23 countries from Africa, Asia and South America. The Registry plans to enroll an additional 17,000 patients with RHD and document their treatments, and their clinical course for at least 2 years. The pregnancy sub-study will document the clinical course of pregnant women with RHD. CONCLUSION: INVICTUS is the largest program of clinical research focused on a neglected cardiovascular disease and will provide new information on the clinical course of patients with RHD, and approaches to anticoagulation in those with concomitant AF.

Prevalence of chronic kidney disease in Nigeria: systematic review of population-based studies.

BACKGROUND: The aim of this study was to identify and discuss published population-based studies carried out in Nigeria that have information on the prevalence of chronic kidney disease (CKD) and have also used the Kidney Disease Outcomes Quality Initiative (KDOQI) practice guidelines in defining CKD, with emphasis on the performance of three estimating equations for glomerular filtration rate (GFR) - Modification of Diet in Renal Disease (MDRD), Cock-croft-Gault, and CKD epidemiology collaboration (CKD-EPI) creatinine equation. MATERIALS AND METHODS: A systematic literature search was carried out in Google, MEDLINE, PubMed, and AJOL database, with the aim of identifying relevant population-based studies with information on the prevalence of CKD in a location in Nigeria. RESULTS: Seven cross-sectional population-based studies were identified. Two of the studies used the Cockcroft-Gault and observed a prevalence of 24.4% and 26%. Four of the studies used the MDRD and the prevalences observed were 12.3%, 14.2%, 2.5%, and 13.4%. One of the studies used the CKD-EPI equation and the prevalence was 11.4%. The male to female ratios of CKD prevalence in six studies were 1:1.9, 0.8:1, 1:1.6, 1:2, 1:1.8, 1:1.4, and the observed risk factors in the studies were old age, obesity, diabetes mellitus, hypertension, family history of hypertension, family history of renal disease, low-income occupation, use of traditional medication, low hemoglobin, and abdominal obesity. CONCLUSION: The prevalence of CKD was high but variable in Nigeria, influenced by the equation used to estimate the GFR. MDRD and CKD-EPI results are agreeable. There is a need for more population-based studies, with emphasis on repeating the GFR estimation after 3 months in subjects with GFR <60 mL/min/1.7 m2.