Sensitivity and specificity of the finger tapping task for the detection of psychogenic movement disorders

Psychogenic movement disorders (PMD) represent a diagnostically challenging group of patients in movement disorders. Finger tapping tests (FTT) have been used in neuropsychiatric evaluations to identify psychogenic conditions, but their use in movement disorders has been limited to the quantification of upper extremity disability in idiopathic Parkinson disease (IPD). We evaluated the ability of the FTT to objectively identify PMD by screening 195 individuals from a movement disorder clinic with IPD, dystonia, essential tremor, or PMD and compared them to 130 normal adults. All subjects performed six-30 second trials using alternate hands. We compared mean FTT score and the coefficient of variation between diagnostic groups. FTT scores in IPD were inversely correlated with Hoehn and Yahr stage (p < .001) and the United Parkinson Disease Rating Scale III (motor) subscale (p < .001). FTT scores were significantly lower in PMD (mean = 41.72) when compared to the other diagnostic groups after controlling for age. The coefficient of variation was not significantly different between diagnostic groups. ROC analysis identified a cutoff FTT ratio of 0.670 or less was 89.1% specific and 76.9% sensitive for the diagnosis of PMD. We conclude the FTT can provide supportive evidence for the diagnosis of PMD

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Conjugal Parkinsonism and Parkinson disease: a case series with environmental risk factor analysis

PD occurring in married couples, conjugal PD represents a unique opportunity to study environmental risk factors for PD due to the shared environment. This retrospective study of non-related married individuals who both presented to the Washington University Movement Disorders Center between 1994 and 2005 investigated the clinical presentation, therapy response, and disease course in conjugal PD subjects. In addition, an occupational, residential, and environmental survey was administered to elucidate potential shared environmental risk factors. Eighteen married subjects had a clinical picture suggestive of idiopathic Parkinson disease. Average age of motor symptom onset was 66.1 (+/-6.22) years in women, 63.4 (+/-7.87) years in men. Subjects cohabitated an average of 39.9 years prior to motor symptom onset in the first affected spouse and an average of nine years elapsed prior to symptom onset in their partner. Disease course in conjugal pairs varied substantially. Seventeen out of eighteen subjects reported at least one environmental exposure of interest. Concordant exposures were residential, non-occupational pesticide and heavy metal exposure, each reported by 77.8% (7/9) of couples. Multiple exposures were reported by 88.9% (16/18) of subjects, most often residential agricultural chemical and heavy metal in combination. This case series of conjugal PD suggests that combined residential exposures may be important in the pathogenesis of idiopathic PD. Larger conjugal PD studies may permit stratification of concordant environmental exposures to determine dose responsiveness and relative contributions to PD risk

Validity and reliability of an occupational exposure questionnaire for parkinsonism in welders

This study assessed the validity and test-retest reliability of a medical and occupational history questionnaire for workers performing welding in the shipyard industry. This self-report questionnaire was developed for an epidemiologic study of the risk of parkinsonism in welders. Validity participants recruited from three similar shipyards were asked to give consent for access to personnel files and complete the questionnaire. Responses on the questionnaire were compared with information extracted from personnel records. Reliability participants were recruited from the same shipyards and were asked to complete the questionnaire at two different times approximately 4 weeks apart. Percent agreement, kappa, intraclass correlation coefficient (ICC), and sensitivity and specificity were used as measures of validity and/or reliability. Personnel files were obtained for 101 of 143 participants (70%) in the validity study, and 56 of the 95 (58.9%) participants in the reliability study completed the retest of the questionnaire. Validity scores for items extracted from personnel files were high. Percent agreement for employment dates and job titles ranged from 83-100%, while ICC for start and stop dates ranged from 0.93-0.99. Sensitivity and specificity for current job title ranged from 0.5-1.0. Reliability scores for demographic, medical and health behavior items were mainly moderate or high, but ranged from 0.19 to 1.0. Most recent job/title items such as title, types of welding performed, and material used showed substantial to perfect agreement. Certain determinants of exposure such as days and hours per week exposed to welding fumes demonstrated mainly moderate agreement (kappa= 0.42-0.47, percent agreement 63-77%); however, mean days and hours reported did not differ between test and retest. The results of this study suggest that participants\u27 self-report for job title and dates employed are valid compared with employer records. While kappa scores were low for some medical conditions and for caffeine consumption, high kappa scores for job title, dates worked, types of welding, and materials welded suggest participants generated reproducible answers important for occupational exposure assessment