The effect of different types of anemia on HbA1c levels in non-diabetics.

BACKGROUND: Diabetes mellitus is one of the most common diseases worldwide with significant morbidity and mortality. HbA1c remains one of the most important methods for diagnosis and monitoring of the disease. Since HbA1c is a reflection of the glucose attached to red blood cells, factors affecting hemoglobin and red blood cells' half-life can influence HbA1c measurements. OBJECTIVE: This study aims to evaluate the effect of different types of anemia including iron deficiency anemia, sickle cell anemia, ß -thalassemia trait, and megaloblastic anemia on HbA1c levels in a tertiary hospital over the past 6 years (2016-2022). METHOD: This is a retrospective chart review study of 324 patients including those with one of the four types of anemia mentioned above and a control group. The control group were healthy adults with normal HbA1c and hemoglobin, who were not known to have diabetes or anemia. Patients with diabetes or prediabetes based on self-reporting or elevated fasting, random blood sugar, or 2 hours post-prandial blood glucose were excluded. RESULTS: The mean HbA1c levels were significantly higher in sickle cell anemia at 5.83% (95% CI = 5.39-6.28) and in iron deficiency anemia at 5.75% (95% CI = 5.68-5.82) when compared to the control group at 5.32% (95% CI = 5.22-5.41). However, the mean HbA1c levels in megaloblastic anemia were 5.38% (95% CI = 5.26-5.5) and 5.45% (95% CI = 5.21-5.69) in beta thalassemia trait, which were not significantly different when compared to the control group. HbA1c significantly decreased from 5.75 to 5.44% after treatment in the iron-deficient group with a p-value of < 0.001. Moreover, lower hemoglobin and higher red cell distribution width correlated with higher HbA1c levels in patients with sickle cell anemia. CONCLUSION: This study found a significant increase in HbA1c levels in iron deficiency anemia and sickle cell disease in patients not known to have diabetes. However, there was no significant effect in those patients with ß-thalassemia trait and megaloblastic anemia. Treatment of iron deficiency anemia significantly decreased the HbA1c level, bringing it back to normal.

Alström Syndrome: A Rare Cause of Severe Insulin Resistance.

Diabetes mellitus is one of the most common diseases worldwide and is a major cause of morbidity and mortality. Type 2 diabetes, with its hallmark being insulin resistance, constitutes the majority of cases. Although usually related to modifiable risk factors, insulin resistance can have genetic causes. Here, we present one of the rare causes of insulin resistance. A 21-year-old man, who was deaf and blind, presented with a 3-week history of polyuria and polydipsia. He was found to have significant hyperglycemia, managed initially with insulin infusion, then he was transitioned to subcutaneous injections. Because he required high doses of insulin and had acanthosis nigricans, insulin resistance was suspected. Putting together his insulin resistance and chronic history of syndromic features, Alström syndrome was considered. Genetic testing revealed a mutation in the ALMS1 gene. The patient was then started on insulin sensitizers with a tapering of insulin with good response. Insulin resistance should be suspected if the insulin requirement is high and if acanthosis nigricans is present. Alström syndrome is a rare causes of insulin resistance. Affected individuals will usually have insulin-resistant diabetes by a young age and associated blindness and deafness. Insulin sensitizers are an important part of the treatment.