High prevalence of reported tremor in Klinefelter syndrome.

Several uncontrolled reports in the literature dating from decades ago suggest a link between Klinefelter syndrome (KS) and essential tremor (ET). Aiming to determine whether this association truly exists, we designed a controlled survey to ascertain the prevalence of reported tremor in KS. We identified subjects with KS through our hospital database and recruited controls among men who were accompanying patients to our Neurology Clinic. The presence of tremor and other variables were recorded employing a previously validated questionnaire. Whereas our control population was slightly older and more frequently reported a family history of tremor, the frequency of reported tremor was significantly higher in subjects with KS than controls with onset at a younger age. In addition, a high proportion of subjects with KS indicated gait imbalance. In summary, our study supports the previously reported association of an ET-like syndrome and KS.