||Background: Moderate hyperhomocysteinemia is a risk for neural
tube defect and neurodegenerative and vascular diseases and has
nutritional, metabolic, and genetic determinants. Its prevalence in
sub-Saharan Africa remains unknown.
Objective: Our goal was to evaluate the prevalence of hyperhomocysteinemia
and the influence of nutritional, metabolic, and genetic
determinants in savanna and coastal regions of Togo and Benin.
Design: Volunteers were recruited from coastal (C groups; n208)
and savanna (S group; n 68) regions. Vitamin B-12, folate, total
homocysteine (tHcy), cystatin C (a marker of glomerular filtration),
and inflammatory and nutritional protein markers were measured in
plasma, and the methylenetetrahydrofolate reductase (MTHFR)
677C3T and 1298A3C polymorphisms and the methionine synthase
2756A3G polymorphism were examined in genomic DNA.
Results: Moderate hyperhomocysteinemia (tHcy 15 mol/L)
was recorded in 62.3% and 29.4% of the subjects from the coast and
savanna, respectively (P 0.0001). A histogram distribution of
tHcy in the coastal groups showed a distinct group, C2 (15% of the
total group), with tHcy 28 mol/L. Folate 6.75 nmol/L (lower
quartile) and MTHFR CT/TT genotype were the 2 main risk factors
for moderate hyperhomocysteinemia in the whole population [odds
ratios: 5.3 (95% CI: 2.5, 11.2; P 0.0001) and 4.9 (1.6, 14.8; P
0.0048), respectively] and in the C2 group [odds ratios: 15.9 (4.5,
56.8; P 0.0001) and 9.0 (2.3, 35.2; P 0.0017), respectively].
Cystatin C was another potent risk factor in the C2 group.
Conclusion:Ahigh prevalence of hyperhomocysteinemia in coastal
West Africa, related to folate concentrations and the MTHFR 677 T
allele, suggests the need to evaluate the influence of hyperhomocysteinemia on disease in this area.