Peripheral neuropathy in myotonic dystrophy. Relation to glucose intolerance

Area of Science:

• Neurology
• Genetics
• Metabolic Disorders

Background:

• Myotonic dystrophy is a multisystem genetic disorder.
• Peripheral neuropathy can be a manifestation of myotonic dystrophy.
• The relationship between glucose intolerance and neuropathy in myotonic dystrophy requires further investigation.

Purpose of the Study:

• To investigate peripheral nerve function in patients with myotonic dystrophy.
• To determine if motor nerve conduction velocity (MNCV) is affected in myotonic dystrophy.
• To assess the relationship between glucose intolerance and peripheral nerve dysfunction in this patient group.

Main Methods:

• Motor nerve conduction velocity (MNCV) was measured in the ulnar, median, and peroneal nerves.
• 24 patients with myotonic dystrophy were compared to a control group.
• Glucose tolerance, age, and adiposity were matched between groups.

Main Results:

• Mean MNCV was significantly slowed in all three tested peripheral nerves (ulnar, median, peroneal) in the myotonic dystrophy group (P < .01).
• The observed peripheral nerve dysfunction was generally subclinical.
• No correlation was found between slowed MNCV and the degree of glucose intolerance.

Conclusions:

• Peripheral nerve dysfunction, evidenced by slowed MNCV, is a common and often subclinical manifestation of myotonic dystrophy.
• This nerve involvement is independent of glucose intolerance associated with the disease.
• These findings highlight the multisystemic nature of myotonic dystrophy.