Drug prescriptions and costs in the treatment of diabetic polyneuropathy

Background and objective: Numerous medications are used in the treatment of diabetic polyneuropathy (PNP) without evidence of their efficacy. This stu dy was undertaken to obtain the costs of drugs prescribed to patients with PNP throughout the Federal Republic of Germany in primary-care practices. Patients and methods: Data (stored in the Medi-Plus data bank of the Instit ute for Medical Statistics, Frankfurt) from 400 primary-care practices were analysed for the year 1996 with regard to diagnoses and prescriptions for 40,112 diabetics over the age of greater than or equal to 20 years. A polyn europathy (PNP) had been diagnosed in 3548 patients (8.8%) (age: 68+/-12 ye ars, 56% women). The cost of medications listed for the treatment of PNP wa s identified and extrapolated to the total prescription cost for treated di abetic PNP in the whole of Germany. In addition the proportion of costs for drugs with unproven efficacy was calculated. Results: Antidepressives were prescribed for 13%, carbamazepine for 4%, and lipoic (thioctic) acid for 41% of diabetics with PNP. Annual costs per pat ient (mean value) were DM 203 for lipoic acid, DM 53 for vasoactive drugs a nd DM 42 for analgesics. Projection for the estimated total number of diabe tic patients with PNP treated in primary care practices (n = 361,400) gave a total cost of DM 116 million (95% confidence limit: DM 109-123), of which DM 41 million (35%) was for medications of unproven efficacy. Conclusion: In Germany one third of drug costs for diabetic patients with P NP in primary care is for medications of unproven efficacy. Cost-effective guidelines for the treatment of diabetic PNP are urgently required.