Urinary Methylmalonic Acid as an Indicator of Early Vitamin B12 Deficiency and Its Role in Polyneuropathy in Type 2 Diabetes

Table 3

Prevalence of electrophysiological markers of neuropathy severity according to urinary methylmalonic acid/creatinine.

Electrophysiological markers of neuropathy severity	uMMAr > 3.5 mmol/mol	uMMAr < 3.5 mmol/mol	P
Sural nerve SNAP amplitude (μV)	1.45 ± 0.41	2.31 ± 1.02	0.03
Sural nerve sensory conduction velocity (m/s)	45.35 ± 6.11	55.98 ± 9.25	0.04
Sural nerve CMAP amplitude (μV)	1.12 ± 0.29	2.09 ± 0.91	0.001
Sural nerve motor conduction velocity (m/s)	40.06 ± 4.21	53.37 ± 7.24	0.005
Superficial peroneal nerve SNAP amplitude (μV)	3.01 ± 1.07	5.56 ± 2.73	0.005
Superficial peroneal nerve sensory conduction velocity (m/s)	40.11 ± 3.03	47.32 ± 5.93	0.023
Superficial peroneal nerve CMAP amplitude (μV)	5.03 ± 2.15	6.01 ± 3.39	0.012
Superficial peroneal nerve motor conduction velocity (m/s)	44.73 ± 4.91	54.12 ± 6.09	0.01
Median nerve sensory conduction velocity (m/s)	53.77 ± 5.16	55.36 ± 5.95	0.08
Median nerve SNAP amplitude (μV)	9.25 ± 3.88	11.28 ± 5.06	0.034
Median nerve motor conduction velocity (m/s)	52.62 ± 4.41	56.15 ± 5.96	0.06
Median nerve CMAP amplitude (μV)	7.31 ± 2.08	9.06 ± 3.16	0.02
Ulnar nerve sensory conduction velocity (m/s)	51.07 ± 5.49	58.10 ± 6.44	0.032
Ulnar nerve SNAP amplitude (μV)	6.93 ± 2.01	8.36 ± 3.17	0.001
Ulnar nerve motor conduction velocity (m/s)	57.90 ± 6.25	61.32 ± 8.04	0.07
Ulnar nerve SNAP amplitude (μV)	6.78 ± 1.84	8.16 ± 2.48	0.022

Key: SNAP: sensory active nerve potential; CMAP: compound motor active potential; uMMAr: urinary methylmalonic acid/creatinine.