FOLATE LEVELS AMONG SICKLE CELL CLIENTS IN APPARENTLY STEADY STATE AND AGE-SEX MATCHED VOLUNTEERS IN AMINU KANO TEACHING HOSPITAL, KANO

Abstract

BACKGROUND: Individuals with Sickle Cell Anaemia (SCA) are at increased risk of
folate deficiency due to high levels of erythropoeitic activity. Folate levels can be assessed
by measuring either the serum or red cell folate assays. Red cell folate is considered more
accurate in determining folate status of individuals since even a transient reduction in folate
intake can result in low serum folate levels despite normal tissue levels. Since folate
deficiency develops in stages, it is important to pick folate deficiency at early stage so as to
prevent its clinical and functional sequelae. There was no earlier study on folate levels of
people with Sickle Cell Anaemia (SCA) in Kano.
AIM: To assess the level of serum and red cell folate in individuals with SCA.
METHODOLOGY: This was a cross sectional study that was carried out among adults and
children with SCA in a tertiary health facility in Kano. Equal number (110) of individuals
with SCA and apparently healthy age and sex matched controls were recruited for the study.
A Structured questionnaire was used to obtain the socio-demographic characteristics of the
study participants. The Full blood count, serum and RBC folate was measured on blood
samples collected from both the cases and controls. Data obtained from the study was
analysed using Statistical Package for Social Sciences (SPSS) version 21.0.
RESULTS: Red cell folate deficiency was commoner in the SCA group (49.1%) compared
to controls (22.9%), P <0.001 (O.R 3.2; 95% CI 1.8 - 5.8). Similarly, serum folate deficiency
was commoner in the SCA group (46.4%) compared to controls (22.0%), P <0.001 (O.R
3.1; 95% CI 1.7 - 5.5). Serum folate is highly specific (96.4%) and sensitive (90.7%) in
determining folate status. It also has high positive predictive value (96.1%) and negative
predictive value (91.5%). Positive likelihood ratio for the test is 25.4 while negative
likelihood ratio is 0.1. Independent predictors of red cell folate deficiency include age less
than 18 years (OR 6.0; 95% CI 2.3 -15.8), female gender (OR 3.3; 95% CI 1.4 – 7.6) and
having a mother with less than Secondary school education or informal education only (OR
8.8; 95% CI 1.4 – 54.5); while those of serum folate are age less than 18 years (OR 3.2; 95%
CI 1.3 – 7.9), female gender (OR 3.1; 95% CI 1.4 – 7.0) and having a mother with less than
Secondary school education (OR 6.0; 95% CI 1.2 – 29.7). Red cell folate deficiency is
associated with low haemtocrit (p= 0.026) and high RDW (p=0.039), while serum folate
deficiency is associated with low haematocrit (p= 0.010) only. One-third of the SCA patients
take folic acid erratically commonly due to forgetfulness (56.4%).
CONCLUSION: Folate deficiency is high among individuals with SCA in Kano possibly
due to the lack of enlightenment and non-compliance with folic acid supplementation. Serum
folate assay is highly specific and sensitive in determining folate status. Therefore, either of
the two assays can be carried out to determine folate status in individuals with SCA
depending on their availability.



KEYWORDS: Sickle cell disease, serum, red cell, folate status, Kano, Nigeria