Project description:BackgroundOrthostatic hypotension (OH) has been cross-sectionally and longitudinally related to dementia in the general population. Whether OH contributes to clinical progression to mild cognitive impairment (MCI) or dementia is less certain. Also, differences in risk of progression between patients with early OH (EOH) versus delayed and/or prolonged OH (DPOH) are unclear.ObjectiveAssess the prevalence of EOH and DPOH, investigate the longitudinal association between EOH and DPOH and either incident MCI or dementia.Methods1,882 patients from the Amsterdam Dementia Cohort [64±8 years; 43% female; n = 500 with subjective cognitive decline (SCD), n = 341 MCI, n = 758 Alzheimer's disease (AD), n = 49 vascular dementia (VaD), n = 146 frontotemporal dementia (FTD), n = 88 Lewy body dementia (DLB)]. Definition OH: systolic blood pressure (BP) drop≥20 mmHg and/or a diastolic BP drop≥10 mmHg at 1 and/or 3 minutes after standing. EOH: OH only at 1 minute, DPOH: OH at (1 and) 3 minutes.ResultsPrevalence OH: 19% SCD, 28% MCI, 41% dementia. Compared to SCD, odds of having OH were highest in patients with VaD and DLB; ORs (95% CI) were 2.6 (1.4-4.7) and 5.1 (3.1-8.4), respectively. After a mean (SD) follow-up of 2.2 (1.4) years, 105 (22%) of SCD or MCI patients showed clinical progression. Compared to patients without OH, those with DPOH had an increased risk of progression; hazard ratio (95% CI) was 1.7 (1.1-2.7), and those with EOH did not; 0.8 (0.3-1.9).ConclusionCompared to SCD, prevalence of OH was higher in MCI and highest in dementia, particularly in VaD and DLB. DPOH, more likely associated with autonomic dysfunction, is a risk factor for incident MCI or dementia.
Project description:ObjectiveTo examine associations of orthostatic hypotension (OH) with dementia and long-term cognitive decline and to update previously published results in the same cohort for stroke with an additional 16 years of follow-up.MethodsWe analyzed data from 11,709 participants without a history of coronary heart disease or stroke who attended the baseline examination (1987-1989) of the prospective Atherosclerosis Risk in Communities (ARIC) study. OH was defined as a drop in systolic blood pressure (BP) of at least 20 mm Hg or a drop in diastolic BP of at least 10 mm Hg on standing. Dementia was ascertained via examination, contact with participants or their proxy, or medical record surveillance. Ischemic stroke was ascertained via cohort surveillance of hospitalizations, cohort follow-up, and linkage with registries. Both outcomes were adjudicated. Cognitive function was ascertained via 3 neuropsychological tests administered in 1990 to 1992 and 1996 to 1998 and a full battery of tests in 2011 to 2013. Scores were summarized and reported as SDs. We used adjusted Cox regression and linear mixed models.ResultsOver ≈25 years, 1,068 participants developed dementia and 842 had an ischemic stroke. Compared to persons without OH at baseline, those with OH had a higher risk of dementia (hazard ratio [HR] 1.54, 95% confidence interval [CI] 1.20-1.97) and ischemic stroke (HR 2.08, 95% CI 1.65-2.62). Persons with OH had greater, although nonsignificant, cognitive decline over 20 years (SD 0.09, 95% CI -0.02 to 0.21).ConclusionsOH assessed in midlife was independently associated with incident dementia and ischemic stroke. Additional studies are needed to elucidate potential mechanisms for these associations and possible applications for prevention.
Project description:BackgroundFew studies have addressed whether anticholinergic (AC) medications for overactive bladder (OAB) cause cognitive decline in individuals with existing cognitive impairment, and whether the APOE ε4 gene increases this risk.ObjectiveTo determine whether OAB AC use is associated with a clinically relevant change in cognitive measures among adults with normal and abnormal cognition.Design setting and participantsThis was a retrospective cohort study using data from the National Alzheimer's Coordinating Center. Patients were enrolled at specialized centers in the USA between 2005 and 2019. Patients with existing OAB AC use, missing APOE ε4 status, and confounding neurologic diagnoses were excluded. New users of an OAB AC were matched 1:1 to patients not taking an OAB AC using propensity scores.InterventionNew use of oxybutynin, tolterodine, solifenacin, trospium, darifenacin, or fesoterodine.Outcome measurements and statistical analysisThe outcome was a change in cognitive function, measured as a ≥1-point increase on the Clinical Dementia Rating (CDR) instrument or a ≥3-point decrease on the Mini-Mental State Examination (MMSE). Conditional logistic regression with odds ratios (ORs) was conducted. We also tested for APOE ε4 effect modification.Results and limitationsAmong 18 835 eligible patients, 782 matched pairs were identified. The most common OAB ACs were oxybutynin (38%) and tolterodine (23%). There was no significant increase in the risk of a clinically relevant cognitive decline among OAB AC users (CDR: OR 1.38, 95% confidence interval [CI] 0.93-2.05; p = 0.11, MMSE: OR 1.06, 95% CI 0.79-1.43; p = 0.70). There was no significant interaction between APOE ε4 status and OAB AC use for the CDR (p = 0.38) or MMSE (p = 0.95) outcomes. Users of oxybutynin or tolterodine had numerically higher odds of a change on the CDR test (OR 1.65, 95% CI 0.98-2.77) that was close to statistical significance (p = 0.06). Limitations include the inability to determine medication dose or duration, and residual confounding.ConclusionsOAB AC use was not associated with a significant change in cognitive function among individuals with normal and abnormal cognition. Further research is necessary to determine if oxybutynin and tolterodine are significantly more likely to cause cognitive decline.Patient summaryUse of a specific class of overactive bladder medication was not associated with negative changes in brain function among patients with either normal or abnormal function. A genetic risk factor for Alzheimer's disease did not predispose individuals to cognitive decline when taking these drugs. Two of the drugs (oxybutynin and tolterodine) may lead to a higher risk of cognitive decline in comparison to other drugs, and this needs further research.
Project description:BackgroundLeukotriene receptor antagonists (LTRAs) alleviate Alzheimer's disease (AD) pathology and improve cognition in animal models; however, clinical evidence is limited. This study aimed to explore the associations between the use of LTRAs (montelukast or zafirlukast) and cognitive performance in people with normal cognition, mild cognitive impairment (MCI), or AD dementia. We hypothesized that LTRA use would be associated with better cognitive performance over time.MethodsThis longitudinal observational study used data from the National Alzheimer's Coordinating Center. Within groups of participants with normal cognition, MCI, or AD dementia, LTRA users were matched 1:3 to non-users using propensity score matching. Cognitive domains including immediate and delayed memory (Wechsler Memory Scale Revised-Logical Memory IA and IIA), psychomotor processing speed (Digit Symbol Substitution Test), and language (animal naming, vegetable naming, and Boston Naming Test) were compared between users and non-users in mixed-effects linear or Poisson regression models.ResultsIn AD dementia, LTRA use was associated with a slower decline in psychomotor processing speed, as measured by the Digit Symbol Substitution Test (Β = 1.466 [0.253, 2.678] symbols/year, n = 442), and language, as measured by animal naming (Β = 0.541 [0.215, 0.866] animals/year, n = 566), vegetable naming (B = 0.309 [0.056, 0.561] vegetables/year, n = 565), and the Boston Naming Test (B = 0.529 [0.005, 1.053] items/year, n = 561). Effect sizes were small but persisted after controlling for a 10% false discovery rate. LTRA use was not associated with changes in memory performance in AD, nor was it associated with changes in cognitive performance in people with normal cognition or MCI. In a post hoc analysis, LTRA use was associated with a slower decline in clinical progression in MCI (B = -0.200 [-0.380, -0.019] points/year, n = 800) and AD dementia (B = -0.321 [-0.597, -0.046] points/year, n = 604) as measured by CDR Sum of Boxes.ConclusionsThe use of LTRAs was associated with preserved function in non-amnestic cognitive domains in AD dementia. The role of leukotrienes and their receptors in cognitive decline warrants further investigation and the leukotriene pathway may represent a target for AD treatment.
Project description:ObjectiveTo investigate the relation between orthostatic hypotension (OH) and posture-mediated cognitive impairment in Parkinson disease (PD) using a cross-sectional and within-group design.MethodsIndividuals without dementia with idiopathic PD included 18 with OH (PDOH) and 19 without OH; 18 control participants were also included. Neuropsychological tests were conducted in supine and upright-tilted positions. Blood pressure was assessed in each posture.ResultsThe PD groups performed similarly while supine, demonstrating executive dysfunction in sustained attention and response inhibition, and reduced semantic fluency and verbal memory (encoding and retention). Upright posture exacerbated and broadened these deficits in the PDOH group to include phonemic fluency, psychomotor speed, and auditory working memory. When group-specific supine scores were used as baseline anchors, both PD groups showed cognitive changes following tilt, with the PDOH group exhibiting a wider range of deficits in executive function and memory as well as significant changes in visuospatial function.ConclusionsCognitive deficits in PD have been widely reported with assessments performed in the supine position, as seen in both our PD groups. Here we demonstrated that those with PDOH had transient, posture-mediated changes in excess of those found in PD without OH. These observed changes suggest an acute, reversible effect. Understanding the effects of OH due to autonomic failure on cognition is desirable, particularly as neuroimaging and clinical assessments collect data only in the supine or seated positions. Identification of a distinct neuropsychological profile in PD with OH has quality of life implications, and OH presents itself as a possible target for intervention in cognitive disturbance.
Project description:AimsSystematically reviewing the literature found orthostatic hypotension (OH) to be associated with an increased risk of incident dementia but limited data were available in those at highest risk, the hypertensive oldest-old. Our aim was to analyse the relationship between OH and incident cognitive decline or dementia in this group and to synthesize the evidence base overall.Method and resultsParticipants aged ≥80 years, with hypertension, were from the Hypertension in the Very Elderly Trial (HYVET) cohort. Orthostatic hypotension was defined as a fall of ≥15 mmHg in systolic and or ≥7 mmHg in diastolic pressure after 2 min standing from a sitting position. Subclinical orthostatic hypotension with symptoms (SOH) was defined as a fall <OH but with unsteadiness, light-headedness, or faintness in the week before blood pressure measurement. Proportional hazard regression was used to examine the relationship between baseline OH, SOH, and cognitive outcomes. There were 3121 in the analytical sample, 538 with OH. Orthostatic hypotension was associated with increased risk of cognitive decline (906 events), hazard ratio (HR) 1.36 (95% confidence interval 1.14-1.59). For incident dementia (241 events), HR 1.34 (0.98-1.84). When competing risk of cardiovascular events were taken into account results were HR 1.39 (1.19-1.62) and HR 1.34 (1.05-1.73), respectively. Subclinical orthostatic hypotension was associated with an increased risk of cognitive decline HR 1.56 (1.12-2.17) and dementia HR 1.79 (1.00-3.20). Combining the results from the HYVET cohort in a meta-analysis with the existing published literature in this area found a 21% (9-35%) increased risk of dementia with OH.ConclusionOrthostatic hypotension indicates an increased risk of dementia and cognitive decline. SOH may also be considered a risk factor, at least in older hypertensive adults. Questions remain regarding the mechanisms and whether interventions to reduce impact of OH could protect cognition.
Project description:BACKGROUND:Alzheimer's Disease (AD) can be conceptualized as a continuum: patients progress from normal cognition to mild cognitive impairment (MCI) due to AD, followed by increasing severity of AD dementia. Prior research has measured transition probabilities among later stages of AD, but not for the complete spectrum. OBJECTIVE:To estimate annual progression rates across the AD continuum and evaluate the impact of a delay in MCI due to AD on the trajectory of AD dementia and clinical outcomes. METHODS:Patient-level longitudinal data from the National Alzheimer's Coordinating Center for n=18,103 patients with multiple visits over the age of 65 were used to estimate annual, age-specific transitional probabilities between normal cognition, MCI due to AD, and AD severity states (defined by Clinical Dementia Rating score). Multivariate models predicted the likelihood of death and institutionalization for each health state, conditional on age and time from the previous evaluation. These probabilities were used to populate a transition matrix describing the likelihood of progressing to a particular disease state or death for any given current state and age. Finally, a health state model was developed to estimate the expected effect of a reduction in the risk of transitioning from normal cognition to MCI due to AD on disease progression rates for a cohort of 65-year-old patients over a 35-year time horizon. RESULTS:Annual transition probabilities to more severe states were 8%, 22%, 25%, 36%, and 16% for normal cognition, MCI due to AD, and mild/moderate/severe AD, respectively, at age 65, and increased as a function of age. Progression rates from normal cognition to MCI due to AD ranged from 4% to 10% annually. Severity of cognitive impairment and age both increased the likelihood of institutionalization and death. For a cohort of 100 patients with normal cognition at age 65, a 20% reduction in the annual progression rate to MCI due to AD avoided 5.7 and 5.6 cases of MCI due to AD and AD, respectively. This reduction led to less time spent in severe AD dementia health states and institutionalized, and increased life expectancy. CONCLUSION:Transition probabilities from normal cognition through AD severity states are important for understanding patient progression across the AD spectrum. These estimates can be used to evaluate the clinical benefits of reducing progression from normal cognition to MCI due to AD on lifetime health outcomes.
Project description:Introduction: Cognitive impairment and orthostatic hypotension (OH) are common, disabling Parkinson disease (PD) symptoms that are strongly correlated. Whether the relationship is causative or associative remains unknown. OH may occur without classic orthostatic symptoms of cerebral hypoperfusion (i.e., lightheadedness or dizziness). Whether longitudinal differences in cognition occur between symptomatic and asymptomatic OH patients has not been explored. Objectives: We characterized the prevalence of OH, orthostatic symptoms, and cognitive impairment among PD patients and compared cognition between patients with and without OH, and between patients with symptomatic and asymptomatic OH. Methods: Our cross-sectional, retrospective, observational study included 226 clinically diagnosed PD patients who underwent repeated standardized evaluations. Among these, 62 had longitudinal follow-up of > 3.5 years. We compared longitudinal Montreal Cognitive Assessment (MoCA) scores between patients remaining OH-free (n = 14) and those without baseline OH that developed OH (n = 28), matched for age, sex, education, and PD duration. We also compared MoCA scores between groups with asymptomatic OH (n = 13) and symptomatic OH (n = 13) matched for the same factors. Results: In the cross-sectional analysis, OH patients had worse cognition. In the longitudinal analysis (mean follow-up = 5.3 years), OH patients had worse cognitive decline (p = 0.027). Cognitive impairment was similar between asymptomatic and symptomatic OH patients in the cross-sectional and longitudinal analyses. Conclusions: OH is associated with cognitive impairment in PD. Further studies are needed in larger cohorts to expand our findings and to determine whether treating OH can prevent or delay cognitive dysfunction.
Project description:ObjectivesWe sought to identify characteristics of individuals with mild cognitive impairment (MCI) that are associated with a relatively high probability of reverting back to normal cognition, and to estimate the risk of future cognitive decline among those who revert.MethodsWe first studied 3,020 individuals diagnosed with MCI on at least 1 visit to an Alzheimer's Disease Center in the United States. All underwent standardized Uniform Data Set evaluations at their first visit with an MCI diagnosis and on a subsequent visit, about 1 year later, at which cognitive status was reassessed. Multiple logistic regression was used to identify predictors of reverting from MCI back to normal cognition. We then estimated the risk of developing MCI or dementia over the next 3 years among those who had reverted, compared with individuals who had not had a study visit with MCI.ResultsAbout 16% of subjects diagnosed with MCI reverted back to normal or near-normal cognition approximately 1 year later. Five characteristics assessed at the first MCI visit contributed significantly to a model predicting a return to normal cognition: Mini-Mental State Examination (MMSE) score, Clinical Dementia Rating (CDR) score, MCI type, Functional Activities Questionnaire (FAQ) score, and APOE ε4 status. Survival analysis showed that the risk of retransitioning to MCI or dementia over the next 3 years was sharply elevated among those who had MCI and then improved, compared with individuals with no history of MCI.ConclusionsEven in a cohort of patients seen at dementia research centers, reversion from MCI was fairly common. Nonetheless, those who reverted remained at increased risk for future cognitive decline.
Project description:A history of depression is a risk factor for dementia. Despite strong epidemiologic evidence, the pathways linking depression and dementia remain unclear. We assessed structural brain alterations in white and gray matter of frontal-executive and corticolimbic circuitries in five groups of older adults putatively at-risk for developing dementia- remitted depression (MDD), non-amnestic MCI (naMCI), MDD+naMCI, amnestic MCI (aMCI), and MDD+aMCI. We also examined two other groups: non-psychiatric ("healthy") controls (HC) and individuals with Alzheimer's dementia (AD). Magnetic resonance imaging (MRI) data were acquired on the same 3T scanner. Following quality control in these seven groups, from diffusion-weighted imaging (n = 300), we compared white matter fractional anisotropy (FA), mean diffusivity (MD), and from T1-weighted imaging (n = 333), subcortical volumes and cortical thickness in frontal-executive and corticolimbic regions of interest (ROIs). We also used exploratory graph theory analysis to compare topological properties of structural covariance networks and hub regions. We found main effects for diagnostic group in FA, MD, subcortical volume, and cortical thickness. These differences were largely due to greater deficits in the AD group and to a lesser extent aMCI compared with other groups. Graph theory analysis revealed differences in several global measures among several groups. Older individuals with remitted MDD and naMCI did not have the same white or gray matter changes in the frontal-executive and corticolimbic circuitries as those with aMCI or AD, suggesting distinct neural mechanisms in these disorders. Structural covariance global metrics suggested a potential difference in brain reserve among groups.