Prevalence of hyperhomocysteinaemia, selected determinants and relation to hypertension severity in Northern-Nigerian hypertensives: the ABU homocysteine survey

Abstract

<jats:p>Background: This study aimed at evaluating the prevalence of hyperhomocysteinaemia in Northern-Nigerian hypertensives and its association with hypertension severity and some major determinants as data regarding these are lackingin sub-Saharan Africa.&#x0D; Method: A Community-based cross-sectional study done on 120 randomly-selected hypertensive patients who responded to an ABU radio frequency modulated invitation for free health-screening at the Ahmadu Bello University (ABU) Medical Centre from January 2016 to June 2016. The percentage of participants with high homocysteine levels, their anthropometric parameters and blood pressures were determined. Plasma homocysteine (hcy) was classified as normal (5-15), moderate (&gt;15-30), intermediate (31-100) and severe (&gt;100) μmol/L. Kruskal-Wallis test was applied and log-transformed homocysteine (Ln10Homocysteine) was correlated with systolic and diastolic blood pressures as well as age, body mass index, fasting blood glucose, glomerular filtration rate, hypertension duration and Ln10folate in males and females using the Pearson’s Correlation analysis.&#x0D; Results: There were 83(69.2%) females and 37(30.8%) males with Median homocysteine of 20.8 μmol/L and 22.0 μmol/L respectively (p=0.003). Hyperhomocysteinaemia was found in 118(98.3%) hypertensives while 2(1.7%) subjects had normo-homocysteinaemia. Moderate hyperhomocysteinaemia (Median, 20.8 μmol/L) was identified in 105(87.5%) and intermediate (Median, 40 μmol/L) in 13(10.8%) (p&lt;0.001). No subject had severe hyperhomocysteinaemia.Homocysteine was higher (p=0.003) in subjects with Stage 2 systolic hypertension. Ln10Homocysteine was significantly (p&lt;0.001) correlated with blood pressure (SBP: r=0.45; DBP: r=0.40) and age (r=0.33).&#x0D; Conclusion: The prevalence of hyperhomocysteinaemia in North-Western Nigerian hypertensives is high as against normal healthy controls. Plasma homocysteine is higher with severe systolic hypertension and positively associated with age.&#x0D; Keywords: Hypertension, Homocysteine, Blood pressure, Northern-Nigerians&#x0D; Funding: No specific grants but Micro Nova Pharmaceuticals Limited, Nigeria and Emzor Pharmaceutical Industries, Lagos, Nigeria supported with drugs.</jats:p>

Hyperhomocysteinemia and its Relations to Conventional Risk Factors for Cardiovascular Diseases in Adult Nigerians: The REMAH Study.

“…Positive association of Hcy with age or alcohol intake have been widely reported 20,25,27 . Though the mechanism underlying this association is vague, it is hypothesized that deficiency in folate, vitamin B12, metabolic changes, poor nutritional absorption and organ function associated with ageing or alcohol intake are possible causes of this anomaly [40][41][42] .…”

Hyperhomocysteinemia and its relations to conventional risk factors for cardiovascular diseases in adult Nigerians: the REMAH study

“…Our decision to use the 10 µmol/L threshold was driven by expert opinions [ 19 ] which suggest that commencement of Hcy reduction at this level is more beneficial than at higher levels. Previous studies of HHcy among hypertensive Nigerians were hospital-based and were done using a threshold of 15 µmol/L [ 14 , 20 ]. The prevalence of HHcy among hypertensive subjects in the current study (23.6%) was strikingly lower than the 56.0% [ 20 ] and 98.3% [ 14 ] reported by the previous studies.…”

“…Previous studies of HHcy among hypertensive Nigerians were hospital-based and were done using a threshold of 15 µmol/L [ 14 , 20 ]. The prevalence of HHcy among hypertensive subjects in the current study (23.6%) was strikingly lower than the 56.0% [ 20 ] and 98.3% [ 14 ] reported by the previous studies. Although the cause of this wide difference is unknown, we hypothesise that difference in study participants may be a plausible explanation bearing that subjects of the current study were drawn from an apparently healthy semi-urban general population with a socio-economic status that could afford them a vitamin-rich diet well known to protect against HHcy.…”

“…Positive association of Hcy with age or alcohol intake have been widely reported [ 14 , 28 , 31 ]. Though the mechanism underlying this association is vague, it is hypothesized that deficiency in folate and vitamin B12; metabolic changes, poor nutritional absorption and organ function associated with ageing or alcohol intake are possible causes of this anomaly [ 44 – 46 ].…”

“…REMAH strictly complied with the Helsinki Guidelines [ 13 ] for conducting research on human subjects. For the purpose of this homocysteine sub-study, we used a prevalence rate of 51% (from a previous survey of HHcy among adult Nigerians) [ 14 ], a margin of error of 8% and static confidence level of 95%, to determine the sample size sufficiently powered for this study. We estimated a total of 150 subjects.…”