Is sedentary lifestyle a critical driver for hypertension burden in Sub-Saharan Africa?: evidence from a community-based population in Ghana and Nigeria

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): National Institute of Health (NIH)

OnBehalf

SIREN as part of the H3 Africa Consortium

Background

Hypertension is the principal risk factor for stroke events in Sub-Saharan Africa (SSA). However, international evidence on the significance of physical inactivity as a critical driver of hypertension risk in SSA is sparse.

Purpose

This study assessed determinants of hypertension risk among a stroke-free population in Ghana and Nigeria.

Methods

Participants were 4,267 stroke-free individuals recruited in the Stroke Investigative Research and Education Network study from Nigeria and Ghana. Data on sociodemographic, lifestyle, cardiovascular risk and blood pressure were collected using standard protocols. Hypertension was defined as systolic blood pressure (SBP) ≥ 140mmHg or diastolic blood pressure (DBP) ≥ 90mmHg or a previous diagnosis or current use of antihypertensive medications. Odds ratio (OR) and 95% confidence interval (CI) for hypertension risk was estimated using logistic regression at P < 0.05.

Results

Mean age was 55.9 ± 14.7 and 1.8% were physically inactive. Mean SBP and DBP were 135.8 ± 24.2mmHg and 82.7 ± 14.3mmHg respectively, and 56.7% had hypertension. Factors associated with hypertension were physical inactivity (OR: 9.09; 95%CI: 4.03, 20.53), being diabetic (OR: 2.70; 95%CI: 1.91, 3.82), being older than 60years (OR: 2.22; 95%CI: 1.78, 2.77) and family history of cardiovascular diseases (OR: 2.02; 95%CI: 1.59, 2.56) and elevated waist circumference (OR: 1.01; 95%CI: 1.00, 1.02).

Conclusion(s): Physical inactivity was the leading risk factor for hypertension in this population. Community-oriented interventions promoting physical activity should help in the control of hypertension among sub-Saharan African population.

APOL1, CDKN2A/CDKN2B, and HDAC9 polymorphisms and small vessel ischemic stroke

OBJECTIVE

Worldwide, the highest frequencies of APOL1-associated kidney variants are found in indigenous West Africans among whom small vessel disease (SVD) ischemic stroke is the most common stroke phenotype. The objective of this study was to investigate the association and effect sizes of 23 selected SNPs in 14 genes of relevance, including the APOL1 G1 variants, with the occurrence of SVD ischemic stroke among indigenous West African participants in the Stroke Investigative Research and Education Network (SIREN) Study.

MATERIALS AND METHODS

Cases were consecutively recruited consenting adults (aged 18 years or older) with neuroimaging-confirmed first clinical stroke. Stroke-free controls were ascertained using a locally validated version of the Questionnaire for Verifying Stroke-Free Status (QVSFS). Logistic regression models adjusting for known vascular risk factors were fitted to assess the associations of the 23 SNPs in rigorously phenotyped cases (N = 154) of SVD ischemic stroke and stroke-free (N = 483) controls.

RESULTS

Apolipoprotein L1 (APOL1) rs73885319 (OR = 1.52; CI: 1.09-2.13, P-value = .013), rs2383207 in CDKN2A/CDKN2B (OR = 3.08; CI: 1.15-8.26, P -value = .026) and rs2107595 (OR = 1.70; CI: 1.12-2.60, P-value = .014) and rs28688791 (OR = 1.52; CI: 1.03-2.26, P-value = .036) in HDAC9 gene were associated with SVD stroke at 0.05 significance level. Polymorphisms in other genes did not show significant associations.

CONCLUSION

This is the first report of a specific association of APOL1 with a stroke subtype. Further research is needed to confirm these initial findings and deepen understanding of the genetics of stroke in people of African ancestry with possible implications for other ancestries as all humans originated from Africa.