Self monitoring of blood glucose in blind diabetic patients.

Abstract

Blind diabetic patients face particular difficulties in blood glucose self monitoring (BGSM). We investigated the quality of BGSM in blind and severely visually impaired diabetic patients and assessed the effects of training in BGSM using a blood glucose meter with voice edition of values and a modified test strip holder for easier placement of blood samples on the strip (One Touch II talk (OT II)). Twenty-six insulin-treated diabetic patients (23 IDDM and 3 NIDDM) participated. At baseline the quality of BGSM was checked in 14 patients who already regularly performed BGSM without external help. Thereafter all 26 patients received an extensive instruction in BGSM for blind patients. At re-examination, after a mean period of 41 days, the quality of BGSM performed by the patients without assistance was checked in three different blood samples. Blood glucose was measured in the same sample by a routine laboratory method. At baseline the mean absolute difference between BGSM and the reference method was -0.3 mmol l(-1) (range; +/- SD) (-7.7-4.8; +/- 2.6 mmol l(-1)); 74% of BGSM measurements deviated by more than 10% from the reference values and 43% by more than 20%. At follow-up all 26 patients reported daily BGSM without external help. The mean absolute difference between BGSM and the reference method was -0.1 (-2.7-2.8; +/- 0.9 mmol l(-1)); 25% of BGSM measurements deviated by more than 10 % from the laboratory reference values and 5% by more than 20%. The results of this study suggest that a substantial number of blind diabetic patients do not perform BGSM on their own at all and in those who do the reliability of the results is poor. However, after extensive instruction, the majority of blind diabetic patients should be able to perform BGSM and to obtain reliable results.