Background and purpose: Morphological brain changes related to hypovitaminosis D have been poorly studied. In particular, the age-related decrease in vitamin D concentrations may explain the onset of white matter abnormalities (WMA) in older adults. Our objectives were (i) to investigate whether there was an association between serum 25-hydroxyvitamin D (25OHD) concentration and the grade of WMA in older adults and (ii) to determine whether the location of WMA was associated with 25OHD concentration. Methods: One hundred and thirty-three Caucasian older community-dwellers with no clinical hydrocephalus (mean 71.6 AE 5.6 years; 43.6% female) received a blood test and a magnetic resonance imaging scan of the brain. The grades of total, periventricular and deep WMA were scored using semiquantitative visual rating scales from T2-weighted fluid-attenuated inversion recovery images. The association of WMA with as-measured and deseasonalized 25OHD concentrations was evaluated with the following covariates: age, gender, body mass index, use of anti-vascular drugs, number of comorbidities, impaired mobility, education level, Mini-Mental State Examination score, medial temporal lobe atrophy, serum concentrations of calcium, thyroid-stimulating hormone and vitamin B12, and estimated glomerular filtration rate. Results: Both as-measured and deseasonalized serum 25OHD concentrations were found to be inversely associated with the grade of total WMA (adjusted b = À0.32, P = 0.027), specifically with periventricular WMA (adjusted b = À0.15, P = 0.009) but not with deep WMA (adjusted b = À0.12, P = 0.090). Similarly, participants with 25OHD concentration <75 nM had on average a 33% higher grade of periventricular WMA than those with 25OHD ≥75 nM (P = 0.024). No difference in average grade was found for deep WMA (P = 0.949). Conclusions: Lower serum 25OHD concentration was associated with higher grade of WMA, particularly periventricular WMA. These findings provide a scientific basis for vitamin D replacement trials.
Although gait disorders are common in Alzheimer's disease (AD), determining which brain structures and related lesions are specifically involved is a goal yet to be reached. Our objective was to systematically review all published data that examined associations between gait disorders and brain imaging in AD. Of 486 selected studies, 4 observational studies met the selection criteria. The number of participants ranged from 2 to 61 community dwellers (29%-100% female) with prodromal or dementia-stage AD. Quantitative gait disorders (ie, slower gait velocity explained by shorter stride length) were associated with white matter lesions, mainly in the medial frontal lobes and basal ganglia. The nigrostriatal dopamine system was unaffected. Qualitative gait disorders (ie, higher stride length variability) correlated with lower hippocampal volume and function. Gait disorders in AD could be explained by a high burden of age-related subcortical hyperintensities on the frontal-subcortical circuits (nonspecific) together with hippocampal atrophy and hypometabolism (specific).
Objective Retrievable inferior vena cava filters (IVCF) have been developed because permanent filters have been associated with an increased risk of recurrent deep venous thrombosis. There is no data on the interactions of IVCF with the inferior vena cava (intrafilter thrombi, insertion through the venous wall) even though this may alter the course after retrieval of the IVCF. Methods A review of 85 consecutive patients undergoing retrieval of IVCF placed at a single center was performed from January 1, 2010 and December 31, 2014. Inferior vena cava filter were examined for presence of intrafilter thrombus at time of retrieval. Filter position and presence of intraluminal thrombus were examined. Patient outcomes, including recurrence of deep vein thrombosis (DVT) and death, were captured at 3 month followup. Results Eighty five patients were identified, with intrafilter thrombi found in 69 (81%) patients and venous wall fragments found in 75 (88%) patients. However, their presence was not associated with an increased risk of recurrent venous thromboembolism (VTE) or death during follow up. Conclusions Intrafilter thrombi and venous wall fragments are frequently found in removed IVCF but are not associated with a worse prognosis. They may not modify the therapeutic management of patients.
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