IQ is an independent predictor of glycated haemoglobin level in young and middle-aged adults with intellectual disability

Aims Here we examined whether intellectual disability is independently associated with hyperglycaemia. Methods We recruited 233 consecutive young and middle-aged adults with intellectual disability. After exclusion of subjects on medication for metabolic diseases or with severe intellectual disability (IQ   70). Results HbA1c level was higher in subjects with moderate intellectual disability (42 ± 9 mmol/mol; 6.0 ± 0.8%) than those in the borderline group (36 ± 4 mmol/mol; 5.5 ± 0.3%) and mild intellectual disability group (37 ± 5 mmol/mol; 5.5 ± 0.5%) groups. HbA1c level was correlated with age, BMI, blood pressure, serum triglycerides and IQ in simple linear regression analysis. Multiple regression analysis indicated that IQ, age, BMI and diastolic blood pressure were independent explanatory factors of HbA1c level. Conclusions An unfavourable effect of intellectual disability on lifestyle and untoward effect of hyperglycaemia on cognitive function may underlie the association of low IQ with hyperglycaemia.