Both letters show the importance of an interdisciplinary approach in treating patients with the lead symptoms of gait unsteadiness and dizziness. This particularly applies to elderly patients.
Professor Hensen mentions the importance of hyponatremia as the cause of an unsteady gait and falls in elderly people. Hyponatremia is a common metabolic cause of impaired attention and vigilance. It favors the occurrence of epileptic seizures. Of particular interest is the association of mild chronic hyponatremia with falls. Mild hyponatremia (>125 mmol/L) is often tolerated if it arises as a side effect of treatment with carbamazepine and does not cause any obvious problems. In such patients, the cause of their falls may be metabolic encephalopathy (hyponatremia); the medication (carbamazepine), which potentially causes dizziness; and insufficiently treated epileptic fits. A thorough history (permanent symptoms versus sudden-onset symptoms) and findings on examination (oculomotor disturbances, ataxia) help with differentiation. The literature supports the stringent diagnostic evaluation and treatment of metabolic disorders in patients with gait disturbances.
We are grateful to Dr Neppert for detailing possible ophthalmologic causes of gait unsteadiness in elderly patients. Bilateral vestibulopathy, however, does not cause any problems at rest and will cause symptoms only when walking or as a result of head movements (1). In the context of ophthalmologic and orthoptists’ findings, the disorder can be confirmed by means of the head impulse test and the reading test with blurred vision during head movements (2).
In conclusion, we should mention that in Munich, a so called “integrated research and treatment center is being set up, which will cover the whole subject range of dizziness, oculomotor disturbances, and gait disturbances (3), with financial support from the Federal Ministry of Education and Research (BMBF, the Bundesministerium für Bildung und Forschung). Clinical researchers, basic researchers, and doctors from various specialties (among others: ophthalmologists; neurologists; specialists in ear, nose, and throat medicine; specialists in psychosomatic medicine; specialists in internal medicine; pediatricians) will collaborate in the new center (http://www.klinikum.uni-muenchen.de/IFB-Schwindel/de/index.html). This collaboration was set up to obviate the familiar problem caused by the fact that traditional medical specialist disciplines have boundaries that militate against optimal patient care. Patients all too often fall between all the chairs of the traditional disciplines. Research into the diagnostic evaluation and treatment of dizziness and gait disturbances requires the cooperation of all disciplines.
Footnotes
Conflict of Interest Statement
The author declares that no conflict of interest exists according to the guidelines of the International Committee of Medical Journal Editors.
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