番茄社区

SEATTLE -- Some two-thirds of older patients seen at a major referral center for balance problems turned out to have significant lower-limb neuropathy, even though most of them had volunteered no complaints about their feet, researchers said here.

Out of 164 patients ages 65 and older seen at the Dent Neurologic Institute in Buffalo, New York, 114 showed symptoms of peripheral neuropathy upon focused testing, reported Akhand Pratap Singh, MBBS, of the institute's Dizziness, Balance and Tinnitus Center, at a poster session during the American Academy of Neurology annual meeting.

However, of these patients, 72% said on initial evaluation that their feet felt fine.

Most of the patients with neuropathy also had other conditions that likely contributed to their balance issues. Just under half also showed signs of vestibulopathy, and one-quarter had intracranial abnormalities. In all, 91 of the 164 patients analyzed had multiple contributing causes.

Yet among patients determined to have a single cause for imbalance, peripheral neuropathy was the most common (34 patients).

"Peripheral neuropathy may be the most common cause for imbalance in the elderly," Singh's group asserted in their poster.

Underlying the study, of Dent patients from 2015 to 2020, was the recognition that many patients with balance troubles don't seem to suffer from dizziness. Once pain or other orthopedic problems are ruled out, that may leave a considerable diagnostic challenge. However, testing for peripheral neuropathy often uncovers symptoms that the patients had not noticed, at a severity that may well compromise their ability to stay upright, the researchers noted.

The 164 patients included in the analysis were those referred to the center with chronic balance issues, with no complaints of vertigo nor movement disorders such as Parkinson's disease. Patients with history of stroke, spinal stenosis, or radiculopathy were excluded as well.

Mean age in the group was 77 (SD 7), and a little over half were men. Of those testing positive for neuropathy, 55% had a history of falls.

Peripheral neuropathy testing consisted of applying a 128-Hz tuning fork to the big toes. Patients were also evaluated for vestibulopathy (primarily via videonystagmography and/or posturography) and intracranial abnormalities such as hydrocephalus and brain lesions.

Nearly two-thirds of patients with peripheral neuropathy showed some type of abnormality in blood test results. Not surprisingly, some 40% had values consistent with diabetes or prediabetes. A more novel finding was that abnormal findings on electrophoresis with immunofixation were positive in 19 patients; another 10 tested positive for hypothyroidism, and 15 were low in vitamin B12.

Singh and colleagues emphasized that the tuning fork test is superior to electromyography for detecting peripheral neuropathy, because the latter is less sensitive, especially in patients not complaining of symptoms.

Limitations to the study included its single-center design and relatively small number of patients; also, Singh and colleagues presented no comparative data for the 50 patients testing negative for neuropathy.

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