While a definition for evidence-based clinical neuropsychological practice (EBCNP) has yet to emerge, it is likely to integrate the same core features as evidence-based medicine; namely, best ...research evidence, clinical expertise, and individual patient needs. Given the nascent stage of EBCNP, suggestions are made to advance evidence-based approaches in both research and practice. The common elements are: recognition that clinical outcomes are recorded at the level of the individual; and to be useful, outcomes research must be presented in a way that can be directly applied on a case-by-case basis. Tracking the outcomes of our clinical services in an evidence-based manner that is publicly verifiable will demonstrate the value of neuropsychological services to our patients, our referral sources, and ultimately to payers.
Background Chronic kidney disease is common and is associated with cardiovascular disease, cerebrovascular disease, and cognitive function, although the nature of this relationship remains uncertain. ...Study Design Cross-sectional cohort using baseline data from the Systolic Blood Pressure Intervention Trial (SPRINT). Setting & Participants Participants in SPRINT, a randomized clinical trial of blood pressure targets in older community-dwelling adults with cardiovascular disease, chronic kidney disease, or high cardiovascular disease risk and without diabetes or known stroke, who underwent detailed neurocognitive testing in the cognition substudy, SPRINT−Memory and Cognition in Decreased Hypertension (SPRINT-MIND). Predictors Urine albumin-creatinine ratio (ACR) and estimated glomerular filtration rate (eGFR). Outcomes Cognitive function, a priori defined as 5 cognitive domains based on 11 cognitive tests using z scores, and abnormal white matter volume quantified by brain magnetic resonance imaging. Results Of 9,361 SPRINT participants, 2,800 participated in SPRINT-MIND and 2,707 had complete data; 637 had brain imaging. Mean age was 68 years, 37% were women, 30% were black, and 20% had known cardiovascular disease. Mean eGFR was 70.8 ± 20.9 mL/min/1.73 m2 and median urine ACR was 9.7 (IQR, 5.7-22.5) mg/g. In adjusted analyses, higher ACR was associated with worse global cognitive function, executive function, memory, and attention, such that each doubling of urine ACR had the same association with cognitive performance as being 7, 10, 6, and 14 months older, respectively. Lower eGFR was independently associated with worse global cognitive function and memory. In adjusted models, higher ACR, but not eGFR, was associated with larger abnormal white matter volume. Limitations Cross-sectional only, no patients with diabetes were included. Conclusions In older adults, higher urine ACR and lower eGFR have independent associations with global cognitive performance with different affected domains. Albuminuria concurrently identifies a higher burden of abnormal brain white matter disease, suggesting that vascular disease may mediate these relationships.
Many patients have serious depression that is nonresponsive to medications, but refuse electroconvulsive therapy (ECT). Early research suggested that isoflurane anesthesia may be an effective ...alternative to ECT. Subsequent studies altered drug, dose or number of treatments, and failed to replicate this success, halting research on isoflurane's antidepressant effects for a decade. Our aim was to re-examine whether isoflurane has antidepressant effects comparable to ECT, with less adverse effects on cognition.
Patients with medication-refractory depression received an average of 10 treatments of bifrontal ECT (n = 20) or isoflurane (n = 8) over 3 weeks. Depression severity (Hamilton Rating Scale for Depression-24) and neurocognitive responses (anterograde and retrograde memory, processing speed and verbal fluency) were assessed at Pretreatment, Post all treatments and 4-week Follow-up.
Both treatments produced significant reductions in depression scores at Post-treatment and 4-week Follow-up; however, ECT had modestly better antidepressant effect at follow-up in severity-matched patients. Immediately Post-treatment, ECT (but not isoflurane) patients showed declines in memory, fluency, and processing speed. At Follow-up, only autobiographical memory remained below Pretreatment level for ECT patients, but isoflurane patients had greater test-retest neurocognitive score improvement.
Our data reconfirm that isoflurane has an antidepressant effect approaching ECT with less adverse neurocognitive effects, and reinforce the need for a larger clinical trial.
Intensively treating hypertension may benefit cardiovascular disease and cognitive function, but at the short-term expense of reduced kidney function.
We investigated markers of kidney function and ...the effect of intensive hypertension treatment on incidence of dementia and mild cognitive impairment (MCI) in 9361 participants in the randomized Systolic Blood Pressure Intervention Trial, which compared intensive versus standard systolic BP lowering (targeting <120 mm Hg versus <140 mm Hg, respectively). We categorized participants according to baseline and longitudinal changes in eGFR and urinary albumin-to-creatinine ratio. Primary outcomes were occurrence of adjudicated probable dementia and MCI.
Among 8563 participants who completed at least one cognitive assessment during follow-up (median 5.1 years), probable dementia occurred in 325 (3.8%) and MCI in 640 (7.6%) participants. In multivariable adjusted analyses, there was no significant association between baseline eGFR <60 ml/min per 1.73 m
and risk for dementia or MCI. In time-varying analyses, eGFR decline ≥30% was associated with a higher risk for probable dementia. Incident eGFR <60 ml/min per 1.73 m
was associated with a higher risk for MCI and a composite of dementia or MCI. Although these kidney events occurred more frequently in the intensive treatment group, there was no evidence that they modified or attenuated the effect of intensive treatment on dementia and MCI incidence. Baseline and incident urinary ACR ≥30 mg/g were not associated with probable dementia or MCI, nor did the urinary ACR modify the effect of intensive treatment on cognitive outcomes.
Among hypertensive adults, declining kidney function measured by eGFR is associated with increased risk for probable dementia and MCI, independent of the intensity of hypertension treatment.
We randomized 74 patients to either a lower Bispectral Index (BIS) regimen (median BIS, 38.9) or a higher BIS regimen (mean BIS, 50.7) during the surgical procedure. Preoperatively and 4-6 wk after ...surgery, the patients' cognitive status was assessed with a cognitive test battery consisting of processing speed index, working memory index, and verbal memory index. Processing speed index was 113.7 +/- 1.5 (mean +/- se) in the lower BIS group versus 107.9 +/- 1.4 in the higher BIS group (P = 0.006). No difference was observed in the other two test battery components. Somewhat deeper levels of anesthesia were therefore associated with better cognitive function 4-6 wk postoperatively, particularly with respect to the ability to process information.
Practice effects on cognitive tests have been shown to further characterize patients with amnestic mild cognitive impairment (aMCI) and may provide predictive information about cognitive change ...across time. We tested the hypothesis that a loss of practice effects would portend a worse prognosis in aMCI.
Longitudinal, observational design following participants across 1 year.
Community-based cohort.
Three groups of older adults: 1) cognitively intact (n = 57), 2) aMCI with large practice effects across 1 week (MCI + PE, n = 25), and 3) aMCI with minimal practice effects across 1 week (MCI - PE, n = 26).
Neuropsychological tests.
After controlling for age and baseline cognitive differences, the MCI - PE group performed significantly worse than the other groups after 1 year on measures of immediate memory, delayed memory, language, and overall cognition.
Although these results need to be replicated in larger samples, the loss of short-term practice effects portends a worse prognosis in patients with aMCI.
Objective: To examine whether processing speed or working memory is the primary information processing deficit in persons with MS. Design: Case-control study. Setting: Hospital-based specialty ...clinic. Participants: 215 adults with clinically definite MS. Main Outcome Measure: Mean demographically corrected T-scores, prevalence rates of impairment and relative risk of impaired Processing Speed and Working Memory Index Scores from the WAIS-WMS III. Results: Deficits in Processing Speed were much more common than Working Memory in all comparisons. This was observed for both relapsing remitting (RRMS) and secondary progressive MS (SPMS) subjects, but accentuated in the latter group. Conclusions: Results strongly suggest that the primary information processing deficit in persons with MS is in speed of processing.
Background: studies of cognitive ageing at the group level suggest that age is associated with cognitive decline; however, there may be individual differences such that not all older adults will ...experience cognitive decline.
Objective: to evaluate patterns of cognitive decline in a cohort of older adults initially free of dementia.
Design, setting and subjects: elderly Catholic clergy members participating in the Religious Orders Study were followed for up to 15 years. Cognitive performance was assessed annually.
Methods: performance on a composite global measure of cognition was analysed using random effects models for baseline performance and change over time. A profile mixture component was used to identify subgroups with different cognitive trajectories over the study period.
Results: from a sample of 1,049 participants (mean age 75 years), three subgroups were identified based on the distribution of baseline performance and change over time. The majority (65%) of participants belonged to a slow decline class that did not experience substantial cognitive decline over the observation period −0.04 baseline total sample standard deviation (SD) units/year. About 27% experienced moderate decline (−0.19 SD/year), and 8% belonged to a class experiencing rapid decline (−0.57 SD/year). A subsample analysis revealed that when substantial cognitive decline does occur, the magnitude and rate of decline is correlated with neuropathological processes.
Conclusions: in this sample, the most common pattern of cognitive decline is extremely slow, perceptible on a time scale measured by decades, not years. While in need of cross validation, these findings suggest that cognitive changes associated with ageing may be minimal and emphasise the importance of understanding the full range of age-related pathologies that may diminish brain function.
Although cognitive decline is typically associated with decreasing practice effects (PEs) (presumably due to declining memory), some studies show increased PEs with declines in cognition. One ...explanation for these inconsistencies is that PEs reflect not only memory, but also rebounds from adapting to task novelty (i.e., novelty effect), leading to increased PEs. We examined a theoretical model of relationships among novelty effects, memory, cognitive decline, and within-session PEs. Sixty-six older adults ranging from normal to severely impaired completed measures of memory, novelty effects, and two trials each of Wechsler Adult Intelligence Scale, 4 th Edition Symbol Search and Coding. Interrelationships among variables were examined using regression analyses. PEs for Symbol Search and Coding (a) were related to different proposed PE components (i.e., memory and novelty effects), such that novelty effect predicted Symbol Search PE (R2 =.239, p<.001) and memory predicted Coding PE (R2 =.089, p=.015), and (b) showed different patterns across stages of cognitive decline, such that the greatest cognitive decline was associated with smallest Coding PE (R2 =.125, p=.004), whereas intermediate cognitive decline was associated with the greatest Symbol Search PE (R2 =.097, p=.040). The relationship between cognitive decline and PE for Symbol Search was partially mediated by novelty effect among older adults with abnormal cognitive decline (model R2 =.286, p<.001). These findings (a) suggest that PE is not a unitary construct, (b) offer an explanation for contradictory findings in the literature, and (c) highlight the need for a better understanding of component processes of PE across different neuropsychological measures.