Falls in community-dwelling stroke survivors: an accumulated impairments model

Falling has been identified as a major complication in persons who have had a stroke. The purpose of this study was to investigate the effect of accumulated impairments on the risk of falling in community-dwelling stroke survivors. METHODS: Community-dwelling stroke survivors were identified from the Kansas City Stroke Study, a large cohort study of stroke survivors. We evaluated the subjects within 14 days of stroke onset. Impairments were determined at baseline and were defined as motor = Fugl-Meyer lower-limb score > 28, sensory = sensory score on National Institutes of Health (NIH) Stroke Scale > 0, and visual = hemianopsia score on NIH Stroke Scale > 0. Accumulated impairments were characterized as motor only (n = 101), motor + sensory (n = 88), and motor + sensory + visual (n = 47). The reference group did not possess motor, sensory, or visual impairments. We completed follow-ups at 1 month, 3 months, and 6 months poststroke to determine the fall status of the subjects. RESULTS: Two hundred eighty subjects were included. Falls were reported by 142 subjects (51%) between 1 month and 6 months poststroke. Univariate analysis revealed that the risk of falling for subjects with motor impairment only was odds ratio (OR) = 2.2 (95% confidence interval [CI] 1.05 to 4.70), motor + sensory impairments OR = 3.1 (95% CI 1.46 to 6.79), and motor + sensory + visual impairments OR = 2.4 (95% CI 1.05 to 5.83) as compared to the group with no motor, sensory, and visual impairments. In multiple logistic regression, the risk of falling increased with motor impairment only and motor + sensory impairments. However, the motor + sensory + visual impairments group had a lower risk of falling. Secondary analysis revealed a significant difference in mobility scores (Orpington Prognostic Scale-balance) among individuals with motor impairment only, motor + sensory impairments, motor + sensory + visual impairments, and the reference group. This lower risk of falling in stroke survivors with motor + sensory + visual impairments may be explained by more involved strokes, more impaired balance, and subsequently less mobility, therefore, lowering their risk of falling. In conclusion, community-dwelling persons who have had a stroke are at a higher risk of falling. However, the risk of falling is not linearly related to the number of impairments. Individuals with motor, sensory, and visual impairments are less mobile and less likely to fall than those individuals with motor deficits only or motor and sensory deficits.     

Three-dimensional display modes for CT colonography: conventional 3D virtual colonoscopy versus unfolded cube projection

The authors compared a conventional two-directional three-dimensional (3D) display for computed tomography (CT) colonography with an alternative method they developed on the basis of time efficiency and surface visibility. With the conventional technique, 3D ante- and retrograde cine loops were obtained (hereafter, conventional 3D). With the alternative method, six projections were obtained at 90 degrees viewing angles (unfolded cube display). Mean evaluation time per patient with the conventional 3D display was significantly longer than that with the unfolded cube display. With the conventional 3D method, 93.8% of the colon surface came into view; with the unfolded cube method, 99.5% of the colon surface came into view. Sensitivity and specificity were not significantly different between the two methods. Agreements between observers were kappa = 0.605 for conventional 3D display and kappa = 0.692 for unfolded cube display. Consequently, the latter method enhances the 3D endoluminal display with improved time efficiency and higher surface visibility.     

Assessment of DE-71, a commercial polybrominated diphenyl ether (PBDE) mixture, in the EDSP male and female pubertal protocols.

DE-71, a commercial mixture, was used to test the sensitivity of the female and male pubertal protocol to detect thyroid active chemicals. These protocols are being evaluated for the U.S. EPA's Endocrine Disruptor Screening Program as part of a Tier I Screening Battery. To examine the ability of these protocols to screen for chemicals that induce the clearance of thyroid hormone, we examined male and female Wistar rats following DE-71 exposure. Rats were gavaged daily with 0, 3, 30, or 60 mg/kg DE in corn oil from postnatal day (PND) 23-53 in the male or PND 22-41 in the female. The temporal effects of DE-71 on liver enzymes and thyroid hormones were measured in another group of males and females following only 5 days of dosing (PND 21 to 26 in females and PND 23 to 28 in males). Serum T4 was significantly decreased at 30 and 60 mg/kg following the 5-day exposures and in the 21-day exposed females. Doses of 3, 30, and 60 mg/kg decreased T4 in 31-day exposed males. Serum T3 was decreased and TSH elevated by 30 and 60 mg/kg in the 31-day exposed males only. Decreased colloid area and increased follicular cell heights (indicative of the hypothyroid state) were observed in thyroids of the 60 mg/kg groups of 20- and 31-day exposed female and males. Increased liver-to-body weight ratios coincided with a significant induction of uridinediphosphate-glucuronosyltransferase (UDGPT; two to four-fold), and ethoxy- and pentoxy-resorufin-O-deethylase (EROD and PROD) at the two highest doses in all exposures. Of the androgen dependent tissues in the 31-day exposed males, seminal vesicle (SV) and ventral prostate (VP) weights were reduced at 60 mg/kg, while testes and epididymal weights were not affected. Preputial separation (PPS) was also significantly delayed by doses of 30 and 60 mg/kg. In the female, the 60 mg/kg dose also caused a significant delay in the age of vaginal opening. Based upon the thyroid hormone response data, this study provides evidence that the 31-day alternative Tier 1 male protocol is a more sensitive test protocol than the 5-day or female pubertal protocol for thyrotoxic agents that act via up-regulation of hepatic metabolism. This apparent greater sensitivity may be due a greater body burden attained following the longer dosing regimen as compared with that of the female protocol, or to gender specific differences in thyroid hormone metabolism. Also, the delay in PPS and reduction in SV and VP weights may indicate a modification or inhibition of endogenous androgenic stimulation directly by DE-71 or a secondary effect that occurs in response to a DE-induced change in thyroid hormones.