Clinical and echocardiographic findings in a cross-sectional study of HIV-infected adults in Enugu, Nigeria.

BACKGROUND: Human immunodeficiency virus (HIV) infection and highly active antiretroviral therapy (HAART) are implicated in cardiovascular diseases. The objective of this study was to evaluate the clinical and echocardiographic findings in HIV-infected adults. METHODS: One hundred HIV subjects on HAART, 100 HAART-naïve patients and 100 controls were recruited in this cross-sectional study. RESULTS: Mean CD4 cell count was significantly higher in the HAART-exposed (408.43 ± 221.62) than the HAART-naïve groups (250.06 ± 154.26) (p < 0.001). Weight loss (49%), skin lesions (14%), body weakness (24%), oral thrush (10%) and lymphadenopathy (10%) were more prevalent in HAART-naïve patients (p < 0.05). Dimensions of aortic root (2.71 cm), left atrium (3.27 cm) and left ventricular mass index (79.95) were significantly higher in HIV-positive subjects on HAART (p < 0.05). CONCLUSIONS: Clinical features of HIV and the CD4 nadir were more prevalent in the HIV-positive, HAART-naïve subjects. Dimensions of the aortic root, left atrium and left ventricle were relatively larger in the HAART-exposed patients while wall thickness and ejection fraction were higher in the HAART-naïve subjects.

Heart rate variability on antihypertensive drugs in black patients living in sub-Saharan Africa.

BACKGROUND: Compared with Caucasians, African Americans have lower heart rate variability (HRV) in the high-frequency domain, but there are no studies in blacks born and living in Africa. METHODS: In the Newer versus Older Antihypertensive agents in African Hypertensive patients trial (NCT01030458), patients (30-69 years) with uncomplicated hypertension (140-179/90-109 mmHg) were randomized to single-pill combinations of bisoprolol/hydrochlorothiazide (R) or amlodipine/valsartan (E). 72 R and 84 E patients underwent 5-min ECG recordings at randomization and 8, 16 and 24 weeks. HRV was determined by fast Fourier transform and autoregressive modelling. RESULTS: Heart rate decreased by 9.5 beats/min in R patients with no change in E patients (- 2.2 beats/min). R patients had reduced total (- 0.13 ms²; p = 0.0038) and low-frequency power (- 3.6 nu; p = 0.057), higher high-frequency (+ 3.3 nu; p = 0.050) and a reduced low- to high-frequency ratio (- 0.08; p = 0.040). With adjustment for heart rate, these differences disappeared, except for the reduced low-frequency power in the R group (- 4.67 nu; p = 0.02). Analyses confined to 39 R and 47 E patients with HRV measurements at all visits or based on autoregressive modelling were confirmatory. CONCLUSION: In native black African patients, antihypertensive drugs modulate HRV, an index of autonomous nervous tone. However, these effects were mediated by changes in heart rate except for low-frequency variability, which was reduced on beta blockade independent of heart rate.

Progress report on the first sub-Saharan Africa trial of newer versus older antihypertensive drugs in native black patients.

BACKGROUND: The epidemic surge in hypertension in sub-Saharan Africa is not matched by clinical trials of antihypertensive agents in Black patients recruited in this area of the world. We mounted the Newer versus Older Antihypertensive agents in African Hypertensive patients (NOAAH) trial to compare, in native African patients, a single-pill combination of newer drugs, not involving a diuretic, with a combination of older drugs including a diuretic. METHODS: Patients aged 30 to 69 years with uncomplicated hypertension (140 to 179/90 to 109 mmHg) and ≤2 associated risk factors are eligible. After a four week run-in period off treatment, 180 patients have to be randomized to once daily bisoprolol/hydrochlorothiazide 5/6.25 mg (R) or amlodipine/valsartan 5/160 mg (E). To attain blood pressure <140/<90 mmHg during six months, the doses of bisoprolol and amlodipine should be increased to 10 mg/day with the possible addition of up to 2 g/day α-methyldopa. RESULTS: At the time of writing of this progress report, of 206 patients enrolled in the run-in period, 140 had been randomized. At randomization, the R and E groups were similar (P ≥ 0.11) with respect to mean age (50.7 years), body mass index (28.2 kg/m(2)), blood pressure (153.9/91.5 mmHg) and the proportions of women (53.6%) and treatment naïve patients (72.7%). After randomization, in the R and E groups combined, blood pressure dropped by 18.2/10.1 mmHg, 19.4/11.2 mmHg, 22.4/12.2 mmHg and 25.8/15.2 mmHg at weeks two (n = 122), four (n = 109), eight (n = 57), and 12 (n = 49), respectively. The control rate was >65% already at two weeks. At 12 weeks, 12 patients (24.5%) had progressed to the higher dose of R or E and/or had α-methyldopa added. Cohort analyses of 49 patients up to 12 weeks were confirmatory. Only two patients dropped out of the study. CONCLUSIONS: NOAAH (NCT01030458) demonstrated that blood pressure control can be achieved fast in Black patients born and living in Africa with a simple regimen consisting of a single-pill combination of two antihypertensive agents. NOAAH proves that randomized clinical trials of cardiovascular drugs in the indigenous populations of sub-Saharan Africa are feasible.

Clinical findings associated with cardiovascular autonomic dysfunction in adult sickle cell anaemia patients.

BACKGROUND: Involvement of the cardiovascular autonomic nervous system in various diseases is often associated with increased morbidity and mortality. OBJECTIVE: The objective of this study was to examine the clinical features associated with cardiovascular autonomic neuropathy (CAN) in adult Nigerians with sickle cell anaemia. METHODS: A cross-sectional study was carried out on 62 steady state sickle cell anaemia patients recruited from the adult out-patient clinic. Cardiovascular autonomic dysfunction was determined based on abnormal values in at least two of five non-invasive tests: Valsalva manoeuvre, heart rate variation during deep breathing, heart rate response to standing, blood pressure response to sustained handgrip, and blood pressure response to standing. All the subjects were initially evaluated in the clinic for symptoms of cardiovascular disease and peripheral vascular disease, and then clinically examined to assess their cardiovascular and neurological status at rest. RESULTS: Out of the 44 patients with cardiovascular autonomic neuropathy 23 were males, while 21 were females. The mean ages were 28.3 +/- 5.8 y for patients with CAN and 28.0 +/- 5.0 y for patients without CAN (P = 0.817). Sickle cell anaemia patients with CAN had significantly lower ankle systolic blood pressure, reduced ankle brachial blood pressure index, mean arterial blood pressure and haematocrit than patients without CAN. Of all the variables evaluated leg ulcers, postural dizziness, erectile dysfunction in men, and history of recurrent acute chest syndromes were found significantly more in patients with CAN than without. Clinical abnormalities tend to worsen with increasing degree of cardiovascular autonomic dysfunction. CONCLUSION: Significant cardiac morbidity is associated with abnormal cardiovascular autonomic function in sickle cell anaemia.

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.