IMPAIRED VIBRATION PERCEPTION THRESHOLD AND LONG-TERM MEAN HBA(1C) INPATIENTS WITH TYPE-1 DIABETES-MELLITUS

The impact of long-term glycaemic control, assessed as HbA(1c) for 5 y ears or more, on vibration perception threshold (VPT) in Type 1 (insul in-dependent) diabetes was investigated. Patients with diabetes onset before 31 years of age and with a diabetes duration of < 26 years were included. HbA(1c) was on average monitored over 9.2 years with 32 mea surements. VPT was measured with biothesiometry on the big toes, and c ompared to non-diabetic reference values standardized for age and heig ht. The biothesiometry readings in the group of 207 patients were elev ated. The median z score (z-transformation of ln (VPT)) was 1.4 in the diabetic population. Patients with HbA(1c) > 7.8% (highest quartile) had a relative risk of 9.2 (95% CI 3.5 < RR < 24.0) to be among the 10 % with the highest z score for VPT, compared to patients with HbA(1c) < 7.8%. Stepwise forward linear regression analysis with the log norma l of the VPT as dependent variable included age, HbA(1c), height, body mass index, macroalbuminuria, and hypertension (> 140/90 mmHg or anti hypertensive treatment) as explaining variables. In conclusion, impair ed VPT was strongly associated with high long-term HbA(1c).