Yadollah Harati, M.D.

Yadollah Harati, M.D.

Patients with autonomic neuropathies – disorders that disrupt involuntary bodily actions like heart rate and sweating – can now receive some information about their individual problem in the newly opened Autonomic Function Laboratory at Baylor College of Medicine in Houston.

"This is one area that until recent years has not received enough attention, but now autonomic disorders are being more and more recognized," said Yadollah Harati, M.D., professor of neurology at BCM and director of the laboratory. "We are now able to measure the degree and type of abnormality, and this will lead to a better understanding of disorders and symptoms."

Pervasive effects

The limited supply of studies on autonomic neuropathies is ironic given their pervasive effects on the autonomic nervous system, which governs all involuntary bodily actions, including heart rate, sweating, salivation, bladder and sexual functions. The autonomic system is involved in many diseases. The most common cause of autonomic nervous system dysfunction is neuropathy related to diabetes.

The severities of autonomic symptoms vary, yet fainting as a result of low or unstable blood pressure ranks among the most common. Neuropathies afflict people of all ages.

"There are 200 different causes for neuropathies, either genetic or from diabetes, inflammation, toxins and medications," said Harati. "We can assume that a good number of patients that have these kinds of neuropathies also have autonomic dysfunction that would have otherwise gone undetected."

Harati's laboratory, one of the few comprehensive diagnostic facilities in the world, is part of the comprehensive Baylor Neuropathy Center. It administers four noninvasive tests that assess patients' sweating, blood pressure and heart rate changes and ultimately aid in the determination of the root cause of patients' neuropathies.

Challenge of overlap in specialties and diseases

"Part of the challenge is that there are many causes for autonomic dysfunction that overlap into different specialties and other diseases," said Harati. "It is essential to look into all aspects of the autonomic system to arrive at a clear diagnosis." The ease of performing these tests and their non-invasive nature make them invaluable in evaluating neuropathies.

Fortunately, Harati said, several collaborative, interdisciplinary clinical trials on neuropathies are underway across the country in hopes of better understanding the disorders.

For patient referrals and appointments, call the Baylor College of Medicine's Autonomic Function Laboratory at 713-798-3935 or 713-798-7419.