Glycosylated Hemoglobin Levels among Non-Diabetic Children with Sickle Cell Anemia at Muhimbili National Hospital. A Case for Establishing Normal Values

Abstract

Background There has been great improvement worldwide in the management of children with sickle cell anemia accompanied with improvement in their life quality. However, with the increase in their lifespan, as expected there is emergence of various endocrinopathies such as Diabetes mellitus As of January 2010, the American Diabetes Association, began advocating the use of Glycosylated Hemoglobin (HbA1c) in diagnosing and monitoring Diabetes mellitus. It has been shown in some of the studies that HbA1c levels in children with sickle cell anemia are lower compared to children without sickle cell anemia. Therefore, there is a need to establish normal range of HbA1c levels corresponding to children with sickle cell anemia. It is important to consider this decrease of HbA1c levels in children with sickle cell anemia when screening them for Diabetes mellitus so as not to miss children with false lower levels of HbA1c. Delay in diagnosis can delay treatment leading to poor diabetic control. Objective To determine normal range of glycosylated hemoglobin levels among non-diabetic children with sickle cell anemia attending clinics at Muhimbili National Hospital in Dar-es-salaam Methodology This was a hospital-based cross sectional study conducted at Paediatric clinics in Muhimbili National Hospital involving children from 9 months to 14 years. 120 children with sickle cell anemia and 40 children without sickle cell anemia were recruited consecutively from these clinics. Data was reported as median and interquartile range or mean ± standard deviation. Chi-square was used for categorical data while for continuous data independent t-test was used for normally distributed data and Mann Whitney test for non-parametric data. Results Median age for children with sickle cell anemia was 4 years with interquartile range (IQR) of (2 - 7) years while median age for children without sickle cell anemia was 5 years with IQR of (3 - 8) years. The reference range of HbA1c levels in children with sickle cell anemia was from 3.4% to 5.2%. Median HbA1c level in children with sickle cell anemia was 4.2% with IQR of (4.1% - 4.6%) while for children without sickle cell anemia median HbA1c levels was 5.3% with IQR of (4.9% - 5.5%). The median HbA1c in children with sickle cell anemia was significantly lower than median in children without sickle cell anemia Conclusion and Recommendation The reference range of HbA1c levels in children with sickle cell anemia was from 3.4% to 5.2%. Children with sickle cell anemia had lower levels of HbA1c compared to children without sickle cell anemia. Health personnel are advised to use HbA1c reference ranges obtained from this study when screening for Diabetes mellitus in children with sickle cell anemia.