PLASMA HOMOCYSTEINE AND SERUM FOLATE LEVELS IN ADOLESCENTS WITH SICKLE CELL DISEASE IN ORLU, IMO STATE, NIGERIA

Abstract

Hyperhomocysteinaemia is a well- established risk factor for several disorders, including
cardiovascular diseases (CVD) and stroke. It also contributes to thrombosis, a frequent
event seen in patients with sickle cell disease. In sickle cell disease, there is accelerated
haemolysis and increased red blood cell production, and risk of depletion of nutrients
particularly folate, vitamin B6 and B12 which are essential to the metabolic conversion of
homocysteine to either cystathionine or methionine. The essence of this study is to
determine the concentrations of plasma homocysteine and serum folate levels in
adolescents with sickle cell disease; HbSS (steady state),HbAS, and compare with sex
and age – matched normal haemoglobin genotype HbAA. The HbAA acted as a control
subjects.
One hundred adolescents each with HbSS, HbAS and HbAA were recruited for this cross
sectional study. Questionnaires were used to obtain information from the participants.
Plasma homocysteine and serum folate levels were assayed using ELISA method and
data obtained was analysed using SPSS version 20, p – value of less than 0.05 was
considered as statistically significant.
The mean plasma homocysteine level was found to be higher among the HbSS
participants when compared to HbAS and HbAA participants (11.27 ± 4.20, 7.58 ±2.30
and 8.71 ± 3.10) respectively p = <0.001. The mean serum folate level shows a significant
increase among HbSS participants when compared to HbAS and HbAA (controls)( 22.6
± 8.72, 9.22 ± 2.78, and 8.99 ± 2.71 respectively, p = <0.001. The study suggests age
dependent increase in plasma homocysteine levels with no gender related differences
among the three haemoglobin genotypes(r = 0.361, p = < 0.011).
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No significant correlation was found between plasma homocysteine and serum folate
levels among different haemoglobin genotypes (r = 0.287, 0.212, and 0.220, respectively,
p = 0.095, 0.146, and 0.126). This study therefore demonstrated an elevated mean
plasma homocysteine level among adolescents with HbSS in Orlu, in spite of elevated
serum folate levels. Longitudinal studies will be needed to determine other predictors of
increase plasma homocysteine levels such as genetic polymorphism, vitamins B6 and
B12, etc.
In view of the elevated plasma homocysteine and serum folate levels observed among
patients with sickle cell anaemia (HbSS), it’s recommended that plasma homocysteine
analysis be included as part of routine investigation for patients with HbSS so that
possible intervention will be instituted to prevent development of complications associated
with hyperhomocysteinaemia.