Is home blood pressure reporting in patients with type 2 diabetes reliable?

The aim of this study was to evaluate the reliability of self-reported home blood pressure (HBP) in patients with type 2 diabetes by comparing the self-reported values with HBP measurements stored in the memory of the blood pressure (BP) monitor. We also examined what factors affect the reliability of HBP measurements. A cross-sectional study was conducted in 280 patients with type 2 diabetes. Patients were requested to perform triplicate morning and evening measurements over a span of 2 weeks and to enter their HBP values into logbooks. Patients were not informed about the memory function of their BP monitoring devices. The concordance rate of HBP reporting was 78.6%. A total of 51.4% of patients (n=144) had >90% concordant data, and 15.7% of patients (n=44) had ⩽50% concordant data. In general, HBP values from the logbook were significantly lower and less variable than those from the stored memory (P<0.05). The most common type of incorrect data was selected data that were reported in the logbooks that were randomly selected from multiple readings by the HBP monitors (55.8%). The concordance rate of HBP reporting significantly correlated with hemoglobin A1c levels (β=-0.156; P=0.0149) and with smoking status (current vs. never, β=-0.165; P=0.0184). In conclusion, HBP measurements from the patients' logbooks were lower and less variable than those from the stored memory in the BP monitors of patients with type 2 diabetes, and the reliability of HBP reporting was affected by glycemic control and smoking status. Repeated instructions regarding HBP measurement to the patients or the use of stored BP measurements is recommended to ensure accurate HBP measurements in patients with type 2 diabetes.