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.

Condom Use at Last Sex and Sexual Negotiation Among Young African American Women in North Carolina: Context or Personal Agency.

African American women are 10.8 times more likely to be diagnosed with HIV compared with White women. This descriptive study fills a gap by examining associations among social and contextual factors and sexual communication, condom use, and safer sex negotiation among African American women. Study participants between 18 and 25 years of age and who reported recent substance use were recruited from three North Carolina counties. A risk behavior survey was administered via audio computer-assisted self-interview, and logistic regression analyses were conducted to assess associations between social and contextual variables and condom use at last sex with a main partner. Education (AOR: 2.078; 95% CI: 1.214, 3.556), sexual communication with a main partner (AOR: 1.079; 95% CI: 1.050, 1.109), and condom use relationship scale (AOR: 1.059; 95% CI: 1.023, 1.098) were positively associated with condom use at last sex, whereas living with a main partner (AOR: 0.447; 95% CI: 0.210, 0.950) and the alcohol and drug problem scale (AOR: 0.971; 95% CI: 0.944, 0.998) were negatively associated with condom use (p < 0.05). The study findings show that among young African American women at risk for HIV, contextual and personal factors may influence condom use. A socio-ecological approach combining personal empowerment, interpersonal, structural, and biobehavioral strategies is necessary in implementing holistic gender-focused HIV prevention programs.

TH1/TH2 cytokine levels as an indicator for disease progression in human immunodeficiency virus type 1 infection and response to antiretroviral therapy.

A recent theory stipulates that during the course of HIV infection, there is a shift in immune response from T-helper 1 to T-helper 2 responses, characterised by elevated secretions of relevant cytokines. Cytokine profiles of 15 asymptomatic (treatment naïve) and 26 symptomatic (undergoing treatment) HIV-1 patients was determined to investigate the validity of this theory. HIV-1 RNA was quantified using the COBAS TaqMan HIV-1 test, CD4 T-cell counts with the FACSCalibur flow cytometer and IL-1, IL-4, IL-6, IL-10 and IFN-gamma cytokine levels by ELISA method. The asymptomatic group had significantly higher RNA levels (p-value; 0.000006) and lower CD4 T-cell counts than the symptomatic group indicating ongoing disease progression in the absence of antiretroviral treatment and a positive response to HIV treatment by the symptomatic group. IL-1, IL-4 and IFN-gamma were undetectable in most study subjects. IL-10 and IL-6 levels was relatively lower in the asymptomatic group (mean value; 206.352 pg/ml, 10.516 pg/ml) than the symptomatic group (mean value; 417.539, 18.387 pg/ml). Lower levels of proinflammatory cytokines (IL-1, IFN-gamma) in both study groups and elevated levels of anti-inflammatory cytokine IL-10, confirms that there is a shift in immune response as HIV infection progress to AIDS. In addition, the presence of a progressive trend of anti-inflammatory cytokine, IL-10 and proinflammatory cytokine, IL-6 in 12 symptomatic patients tested 3 months after antiretroviral therapy indicates an attempt by antiretrovirals to restore immune function.