Vitamin B12 Supplementation in Diabetic Neuropathy

Sural Nerve conduction velocity measured as m/s

Sural Nerve conduction amplitude measured as μV

Michigan Neuropathy Screening Instrument questionnaire (The Michigan Neuropathy Screening Instrument (MNSI) includes two separate assessments, a 15-item self-administered questionnaire and a lower extremity examination. the questionnaire is scored by summing abnormal responses. Responses are added to obtain a total score. 'Yes' responses to questions 1-3, 5-6, 8-9, 11-12, 14-15 are each counted as one point. 'No' responses to questions 7 and 13 each count as one point. Question 4 was considered to be a measure of impaired circulation and question 10 a measure of general asthenia and were not included in the published scoring algorithm. A score of ≥ 7 was considered abnormal.

Michigan Neuropathy Screening Instrument Examination (The Michigan Neuropathy Screening Instrument (MNSI) includes two separate assessments, a 15-item self-administered questionnaire that is scored by summing abnormal responses, and a lower extremity examination that includes inspection and assessment of vibratory sensation and ankle reflexes and is scored by assigning points for abnormal findings.A score ≥ 2 was considered abnormal. Abnormality in each item is graded between 0.5 and 1 and at least more than 2 abnormal items are needed to reach the score of neuropathy. )

Electrochemical Skin Conductance in hands and feet measured by SUDOSCAN

CARTs were performed with Autonomic Nervous System Reader and included R-R variation during deep breathing [Mean Circular Resultant , Valsalva maneuver , 30:15 ratio expressed as postural index, and blood pressure response to standing (orthostatic hypotension)

Vibration perception threshold was measured using a Biothesiometer

painDETECT questionnaire consists of seven questions that address the quality of neuropathic pain symptoms; it is completed by the patient and no physical examination is required. The first five questions ask about the gradation of pain, scored from 0 to 5 (never = 0, hardly noticed = 1, slightly = 2; moderately = 3, strongly = 4, very strongly = 5). Question 6 asks about the pain course pattern, scored from -1 to 2, depending on which pain course pattern diagram is selected. The final score between -1 and 38, indicates the likelihood of a neuropathic pain component. A score of ≤ 12 indicates that pain is unlikely to have a neuropathic component (< 15%), while a score of ≥ 19 suggests that pain is likely to have a neuropathic component (> 90%). A score between these values indicates that the result is uncertain and a more detailed examination is required.

Diabetes Quality of Life Brief Clinical Inventory (ThE DQOL questionnaire we used is a 15-items, brief-focused version of the Diabetes Quality of Life (DQOL) questionnaire developed in the DCCT and lowest score means worse quality of life whereas higher values indicate better quality of life)

serum vitamin B12 levels

report of any adverse events