ICD-9 CM code 333.1 as an identifier of patients with essential tremor: a study of the positive predictive value of this code.

Background/aims: Health outcomes research often uses administrative databases. Patients with the diseases of interest are identified using International Classification of Diseases (ICD-9 CM) codes. The utility of the code for essential tremor (ET), 333.

Interest in participating in clinical research: A study of essential tremor patients.

Enrolling essential tremor (ET) patients in clinical research can be challenging. Investigators can maximize recruitment by targeting patient subgroups with greater interest in participation. Nothing has been published on factors that are associated with higher levels of interest in participation.

Jaw tremor: prevalence and clinical correlates in three essential tremor case samples.

The spectrum of involuntary movements seen in essential tremor (ET) is limited. Jaw tremor is one such movement. The prevalence and clinical correlates of jaw tremor have not been studied in detail.

Essential tremor: mild olfactory dysfunction in a cerebellar disorder.

Olfactory dysfunction has been reported to occur in patients with cerebellar disorders, including degenerative ataxias and essential tremor (ET). Previous studies have not considered the effects of mild cognitive deficits, which can occur in ET, and could explain the lower olfaction test scores in ET cases. We more than doubled our initial sample (37 ET cases and 37 controls) [Louis ED, Bromley SM, Jurewicz EC, Watner D.

Interaction between blood lead concentration and delta-amino-levulinic acid dehydratase gene polymorphisms increases the odds of essential tremor.

Blood lead (BPb) concentrations are elevated in essential tremor (ET) cases. The delta-amino-levulinic acid dehydratase (ALAD) gene codes for ALAD, the principal enzyme involved in lead kinetics. Carriers of the ALAD-2 allele may be more susceptible to lead toxicity.

Factor structure of motor signs in essential tremor.

Motor signs in essential tremor (ET) are varied. Patients may have limb tremors, including postural, kinetic (e.g.

Feasibility and validity of a modified finger-nose-finger test.

In essential tremor (ET) research, it is important to obtain standardized, objective data on tremor severity. Often, it is not possible to carry out in-person or videotaped neurological examinations. In place of these, handwriting samples can be collected, but they do not capture all of the variance in tremor severity.

Association between essential tremor and blood lead concentration.

Lead is a ubiquitous toxicant that causes tremor and cerebellar damage. Essential tremor (ET) is a highly prevalent neurologic disease associated with cerebellar involvement. Although environmental toxicants may play a role in ET etiology and their identification is a critical step in disease prevention, these toxicants have received little attention.