The 3-Item "Apathy" Subscale Within the GDS-15 Is Not Supported in De Novo Parkinson's Disease Patients: Analysis of the PPMI Cohort.

This study examined individual components of the Geriatric Depression Scale-15 (GDS-15) to determine whether the 3-item Withdrawal-Apathy-Lack of Vigor (WAV) subscale, which has been validated in older adults and advanced Parkinson's disease (PD), was applicable to newly diagnosed patients with PD. Baseline Parkinson's Progression Markers Initiative (PPMI) data (n = 345), including GDS-15 and Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) depression, apathy, and anxiety scores, were examined. Data reduction techniques (i.e., principal components, confirmatory factor analyses) were used. Model fit was poor for the previously identified GDS-15 factor structures. Via principal components analysis, 5 components were identified, none of which reflected the 3-item WAV subscale previously reported in the literature. Internal consistency of the GDS-15 was acceptable, as was the internal consistency for the largest component (labeled "Dysphoria"). All 5 components significantly correlated with the MDS-UPDRS depression, apathy, and anxiety items. Model fit was fair for the "Dysphoria" factor only. Overall, the 3-item WAV factor reported in previous literature was not supported in this sample of de novo PD patients.

Informant report of practical judgment ability in a clinical sample of older adults with subjective cognitive decline, mild cognitive impairment, and dementia.

Despite the importance of capturing problems with judgment and decision-making during neuropsychological evaluations of older adults, there are a limited number of validated measures and no informant rating scales. We developed an informant measure that captures compromised judgment related to safety, medical, financial, and social-ethical issues After item refinement and piloting in a memory disorders clinic, we utilized the Test of Practical Judgment-Informant (TOP-J-Informant) at two clinics in the Midwestern U.S., including 189 patient/informant dyads (mean age = 79.0, median years of education = 13, % female = 67.7) with various preclinical and clinical dementia conditions. We found psychometric support, including evidence for convergent, divergent, and criterion-related validity, and internal consistency. Importantly, we were able to discriminate between diagnostic groups in the expected direction. The TOP-J-Informant is brief (<5 minutes), easy to administer, and can reveal areas of concern related to poor judgment when administered in the context of a neuropsychological evaluation or clinic visit.

A comparison of the thermal properties of 2- and 3-fluted drills and the effects on bone cell viability and screw pull-out strength in an ovine model.

BACKGROUND: Drilling of bone is associated with an increase in temperature of the surrounding bone which may result in osteonecrosis. METHODS: In this study, cutting efficiency and thermal properties of one 2-fluted drill and two 3-fluted drills were determined in vitro using a porcine model. Drills were then used to create pilot holes in an in vivo ovine model to facilitate implantation of pedicle screws. The effect of the characteristic thermal profiles of each drill on cortical bone cell viability and screw pull-out strength was then assessed. FINDINGS: Cutting efficiencies of both 3-fluted designs were found to be greater than that of the 2-fluted drill, but this did not translate into a decrease in the maximum temperatures during drilling for both drills. Histologically, no empty osteocyte lacunae were seen at 2 or 4 weeks, suggesting that temperatures were not sufficiently high enough to induce thermonecrosis in the ovine tibia. No differences were found in the pull-out strength of the screws. INTERPRETATION: Both 2- and 3-fluted drills are currently in clinical use. Despite the theoretical advantage that 3-fluted drills possess over their 2-fluted counterparts, there is a lack of evidence in the literature in support of their use. In this study the observed increases in cutting efficiency of the 3-fluted drills tested did not translate into a reduction in heat generation or improvement in bone healing or screw fixation.