title: Tremor in the elderly: Essential and aging-related tremor.
abstract: BACKGROUND
  Isolated tremor in the elderly is commonly diagnosed as essential tremor (ET). The prevalence of tremor increases steeply with increasing age, whereas hereditary tremor is becoming less common. Moreover, late-manifesting tremor seems to be associated with dementia and earlier mortality. We hypothesize that different entities underlie tremor in the elderly.
  
  
  METHODS
  Two thousand four hundred forty-eight subjects from the Longitudinal Study of Aging Danish Twins older than 70 y answered screening questions for ET in 2001. Two thousand fifty-six (84%) participants drew Archimedes spirals to measure their tremor severity, and classical aging phenotypes were assessed. A subgroup of 276 individuals fulfilling either screening criteria for ET or being controls were personally assessed. Medications and mortality data are available.
  
  
  RESULTS
  The spiral score increased with age. The spiral score correlated with tremor severity. For the whole cohort, mortality was significantly correlated with the spiral score, and higher spiral scores were associated with lower physical and cognitive functioning. Multivariate analysis identified higher spiral scores as an independent risk factor for mortality. In contrast, the ET patients did not show an increased but rather a lower mortality rate although it was not statistically significant. Consistent with a slower than normal aging, they were also physically and cognitively better functioning than controls.
  
  
  CONCLUSIONS
  Because incident tremors beyond 70 y of age show worse aging parameters and mortality than controls and ET, we propose to label it 'aging-related tremor' (ART). This tremor starts later in life and is accompanied by subtle signs of aging both cognitively and physically. More detailed clinical features and pathogenesis warrant further assessment.
authors.affiliation: Department of Neurology, Universitätsklinikum Schleswig-Holstein, Kiel Campus, Christian-Albrechts-University, Kiel, Germany.
authors.forename: Günther
authors.initials: G
authors.lastname: Deuschl
authors.affiliation: Institute of Public Health, The Danish Twin Registry and the Danish Aging Research Center, University of Southern Denmark, Odense, Denmark.
authors.forename: Inge
authors.initials: I
authors.lastname: Petersen
authors.affiliation: Department of Neurology, Universitätsklinikum Schleswig-Holstein, Kiel Campus, Christian-Albrechts-University, Kiel, Germany.
authors.forename: Delia
authors.initials: D
authors.lastname: Lorenz
authors.affiliation: Institute of Public Health, The Danish Twin Registry and the Danish Aging Research Center, University of Southern Denmark, Odense, Denmark.|Department of Clinical Genetics, Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense, Denmark.
authors.forename: Kaare
authors.initials: K
authors.lastname: Christensen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D003718:Denmark / Q000453:epidemiology; D004200:Diseases in Twins / Q000453:epidemiology*; D020329:Essential Tremor / Q000453:epidemiology / Q000401:mortality / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D012720:Severity of Illness Index; D014202:Tremor / Q000453:epidemiology / Q000401:mortality / Q000503:physiopathology*
keywords: Essential tremor; aging; aging-related tremor; mortality; predictors for mortality