Under-recognition of polyneuropathy in persons with diabetes by nonphysician electrodiagnostic services providers

Healthcare providers commonly refer patients to physiatrists and neurologists for electrodiagnostic testing when they have symptoms suggestive of a peripheral nerve disorder. Published practice guidelines specify that electrodiagnostic medicine consultants should possess special neurologic and procedural training in this area. We recently found that despite these practice guidelines, physical therapists, chiropractors, and podiatrists perform 17% of electrodiagnostic studies in the United States. These findings prompted the current investigation examining electrodiagnostic care across different providers for an important target population-persons with diabetes.

A retrospective cohort of patients with diabetes who underwent electrodiagnostic testing in 1998 was identified in the MarketScan Commercial Claims & Encounters Database (The MEDSTAT Group) using CPT and ICD9CM codes. This database represents the healthcare claims for 16 million Americans in private and employer-based health plans. The outcome of interest was the rate of polyneuropathy identification across different providers, controlling for patient characteristics.

There were 6381 electrodiagnostic encounters for persons with diabetes in 1998. Polyneuropathy identification rates were highest for physiatrists, osteopathic physicians, and neurologists (12.5%, 12.2%, and 11.9%, respectively). Podiatrists and physical therapists identified 2.4% and 2.1%, respectively, as having polyneuropathy-rates about one sixth that of physiatrists and neurologists despite controlling for casemix differences. Nonphysician providers who did not recognize polyneuropathy performed almost exclusively EMG testing (>90%) at the expense of nerve conduction studies.

This study raises concerns about the quality of electrodiagnostic testing by nonphysician providers for persons with diabetes. These results should prove useful for physicians, third-party payers, and health policy makers when confronting issues related to provision of electrodiagnostic services.