Prostaglandin E1 plus methylcobalamin combination therapy versus prostaglandin E1 monotherapy for patients with...

Prostaglandin E1 (P) or methylcobalamin (M) treatment has been suggested as a therapeutic approach for diabetic peripheral neuropathy (DPN) in many clinical trial reports. However, the combined effects of 2 drugs still remain dubious.

The aim of this report was to evaluate the efficacy of M plus P (M + P) for the treatment of DPN compared with that of P monotherapy, in order to provide a reference resource for rational drug use.

Randomized controlled trials (RCTs) of M + P for DPN published up to September 2017 were searched. Risk ratio (RR), mean difference (MD), and 95% confidence interval (CI) were calculated and heterogeneity was assessed with the I test. Subgroup and sensitivity analyses were also performed. The outcomes measured were as follows: the clinical efficacy, median motor nerve conduction velocities (MNCV), median sensory nerve conduction velocity (SNCV), peroneal MNCV, peroneal SNCV, and adverse effects.

Sixteen RCTs with 1136 participants were included. Clinical efficacy of M + P combination therapy was significantly better than P monotherapy (fifteen trials; RR 1.25, 95% CI 1.18-1.32, P < .00001, I = 27%). Compared with P monotherapy, the pooled effects of M + P combination therapy on nerve conduction velocity were (MD 6.29, 95% CI 4.63-7.94, P < .00001, I = 90%) for median MNCV, (MD 5.68, 95% CI 3.53-7.83, P < .00001, I = 94%) for median SNCV, (MD 5.36, 95% CI 3.86-6.87, P < .00001, I = 92%) for peroneal MNCV, (MD 4.62, 95% CI 3.48-5.75, P < .00001, I = 86%) for peroneal SNCV. There were no serious adverse events associated with drug intervention.

M + P combination therapy was superior to P monotherapy for improvement of neuropathic symptoms and NCVs in DPN patients. Moreover, no serious adverse events occur in combination therapy.