[Dysfunction of the upper respiratory airways in patients with essential tremor].

OBJECTIVES

To investigate pulmonary function abnormalities in essential tremor.

METHODS

We obtained maximal inspiratory and expiratory flow-volume curves in 41 unselected patients with essential tremor (14 males, 27 females, age 61.7 +/- 2.14 years). Severity of essential tremor was evaluated using the Fahn, Tolosa and Marin clinical scale.

RESULTS

Sixteen patients (39.0%) had flow oscillations on the flow-volume curves (8 only during inspiration, 7 during inspiration and expiration, and 1 with flow oscillations during inspiration and obstructive pattern). The duration and severity of the essential tremor did not influence the pattern of the curve, but abnormal curves were more frequent in patients with voice tremor. Although there were a number of significant correlations between essential tremor scales and spirographic parameters, they were of very low range. Four patients (9.8%) fulfilled criteria for physiological upper airway obstruction: 2 had smooth flow-volume loop contour and 2 had flow oscillations in inspiration and expiration.

CONCLUSION

Abnormalities in flow-volume loop contour are a usual finding in essential tremor. This probably reflects involvement of the upper airway musculature, that in some patients can produce clinical upper airway obstruction.