The relative influence of diabetes mellitus-related and physiological factors on vibration perception thresholds was assessed in 353 patients in a hospital-based setting (173 insulin-dependent and 180 non-insulin dependent patients, aged 51.1 +/- 15.9 years) and 80 healthy controls (aged 43.3 +/- 15.2 years) employing a Biothesiometer. Vibration perception thresholds were bilaterally measured at the thumbs, medial malleoli and halluces. Sixty (17.0%) older patients had off-scale thresholds (> 50 V). As no systematic side differences were found, values of contralateral sites were averaged. Considering the effects of age, height, gender and skin temperature in controls, age accounted for 46.7 and 52.2% threshold variance at the ankles and halluces, respectively, while height explained 5.1 and 5.1%, respectively. At the thumbs, only age was of relevance. Age relationships with vibration thresholds in health did not differ from published reports at any site. In the patient group, influences of age, height, gender, skin temperature, years from diagnosis, HbAlc, serum creatinine, drop in systolic blood pressure on standing, and ankle/arm blood pressure indices were assessed for each type of diabetes. For both types, age and height again had relevant effects at the lower extremities as did age and gender at the thumbs. Skin temperature was only marginally significant at the halluces of NIDDM patients. Of the disease-related factors, HbAlc had the strongest effect: for both IDDM and NIDDM higher levels were associated with lower vibration sensitivity. Increasing disease duration led to significantly higher thresholds in IDDM patients.(ABSTRACT TRUNCATED AT 250 WORDS)