The relationship between HbA1c level, symptoms and self-rated health in type 2 diabetic patients.

OBJECTIVE: Improving glycaemic control is generally supposed to reduce symptoms experienced by type 2 diabetic patients, but the relationships between glycated haemoglobin (HbA(1c)), diabetes-related symptoms, and self-rated health (SRH) are unclarified. This study explored the relationships between these aspects of diabetes control.
DESIGN: A cross-sectional study one year after diagnosis of type 2 diabetes.
SUBJECTS: A population-based sample of 606 type 2 diabetic patients, median age 65.6 years at diagnosis, regularly reviewed in primary care. MAIN OUTCOME MEASURES: The relationships between HbA(1c), diabetes-related symptoms, and SRH.
RESULTS: The patients' median HbA(1c) was 7.8 (reference interval: 5.4-7.4 % at the time of the study). 270 (45.2%) reported diabetes-related symptoms within the past 14 days. SRH was associated with symptom score (γ = 0.30, p < 0.001) and HbA(1c) (γ = 0.17, p = 0.038) after correction for covariates. The relation between HbA(1c) and symptom score was explained by SRH together with other confounders, e.g. hypertension (γ = 0.02, p = 0.40). The relation between the symptom fatigue and SRH was not explained by symptom score and significantly modified the direct association between symptom score and SRH.
CONCLUSIONS: Symptom relief may not occur even when HbA(1c) level is at its lowest average level in the natural history of diabetes, and symptoms and SRH are closely linked. Monitoring symptoms in the clinical encounter to extend information on disease severity, as measured e.g. by HbA(1c), may help general practitioners and patients to understand the possible impact of treatments and of disease manifestations in order to obtain optimum disease control.