Senile tremor - What is the prevalence and severity of tremor in older adults

Background/Setting: It is well recognized that mild trem- or is common amon g older adults, but the prevalence and clinical characteristics of this tre mor have not been studied in detail. Objectives: To examine a cohort of nor mal older adults to: (1) ascertain the prevalence of mild test-detectible tremor; (2) quantify the severity and functional impact of this tremor, and (3) determine whether age, gender and concomitant illness predict the seve rity of tremor. Participants: 76 normal older adults > 55 years of age (mea n age = 73.7 years). Design: Healthy older adults were identified in a comm unity-based case-control study of essential tremor in Washington Heights-In wood, New York. All subjects underwent a medical interview and a videotaped neurological examination. The examination included six tests: arm extensio n, pouring water, drinking water, using a spoon, finger-to-nose movements, and drawing spirals with each arm. Two neurologists rated the severity of t remor using a 0 to +3 clinical rating scale and a total tremor score (TTS) was calculated (range = 0-36). Forward stepwise linear regression was used to determine the association between TTS and other variables. Results: Virt ually all (75 or 98.7%) showed signs of tremor (TTS > 0.5). The mean TTS = 6.3 (range = 0-14.5), corresponding to a tremor that was either mild or int ermittent. Twenty-eight of 76 (36.8%) received tremor ratings of +2 (clearl y oscillatory tremor of moderate amplitude and usually present) during at l east one of the six tests; a tremor rating of +2 was 2.1 times more likely to occur in the nondominant than in the dominant hand. Those who were aged 57-74 years had a lower mean TTS (5.8) than those aged 75-93 (6.8), but thi s was not significant. Only 2 patients (2.6%) answered 'yes' to the questio n 'do you have uncontrollable shaking in your hands?' None was taking medic ation to treat tremor. Gender, ethnicity, concomitant illness (diabetes, ar thritis, heart disease), and medications were not associated with a higher TTS. Conclusion: Mild but test-detectible tremor was present in almost all normal older adults, and in one-third this tremor attained a moderate ampli tude during at feast one activity. Characterization of this tremor would be of value to practitioners who care for older adults. Copyright (C) 2000 S. Kargei AG, Basel.