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In 2020, the Lancet Commission identified 12 modifiable factors that increase population-level dementia risk. It is unclear if these risk factors co-occur among individuals in a clinically meaningful way. Using latent class analysis, we identified profiles of modifiable dementia risk factors in dementia-free adults aged 60-64 years from the UK Biobank. We then estimated associations between these profiles with incident dementia, cognition, and neuroimaging outcomes, and explored the differences across profiles in the effects of a polygenic risk score for Alzheimer's disease on outcomes. In 55,333 males and 63,063 females, three sex-specific latent profiles were identified: cardiometabolic risk, substance use-related risk, and low risk. The cardiometabolic risk profile in both males and females was associated with greater incidence of all-cause dementia (male: OR [95% CI] = 2.33 [2.03, 2.66]; female: OR [95% CI] = 1.44 [1.24, 1.68]), poorer cognitive performance, greater brain atrophy, and greater white matter hyperintensity volume compared to the low risk profile. The substance use-related risk profile in males was associated with poorer cognitive performance and greater white matter hyperintensities compared to the low risk profile, but no difference in all-cause dementia incidence was observed (OR [95% CI] = 1.00 [0.95, 1.06]). In females, the substance use-related risk profile demonstrated increased dementia incidence (OR [95% CI] = 1.58 [1.57, 1.58]) and greater brain atrophy but smaller white matter hyperintensity volume compared to the low risk profile. The polygenic risk score had larger effects among females, and differentially influenced outcomes across profiles; for instance, there were larger effects of the polygenic risk score on atrophy in the cardiometabolic profile vs. the low risk profile among males, and larger effects of the polygenic risk score on loss of white matter integrity in the cardiometabolic profile vs. the low risk profile among females. These results reveal three modifiable dementia risk profiles, their unique cognitive/neuroimaging outcomes, and their interactions with genetic risk for Alzheimer's disease. These differences highlight the need to consider population heterogeneity in risk prediction tools and in planning personalized prevention strategies.
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INTRODUCTION: We investigated the effect of perivascular spaces (PVS) volume on speeded executive function (sEF), as mediated by white matter hyperintensities (WMH) volume and plasma glial fibrillary acidic protein (GFAP) in neurodegenerative diseases. METHODS: A mediation analysis was performed to assess the relationship between neuroimaging markers and plasma biomarkers on sEF in 333 participants clinically diagnosed with Alzheimer's disease/mild cognitive impairment, frontotemporal dementia, or cerebrovascular disease from the Ontario Neurodegenerative Disease Research Initiative. RESULTS: PVS was significantly associated with sEF (c = -0.125 ± 0.054, 95% bootstrap confidence interval [CI] [-0.2309, -0.0189], p = 0.021). This effect was mediated by both GFAP and WMH. DISCUSSION: In this unique clinical cohort of neurodegenerative diseases, we demonstrated that the effect of PVS on sEF was mediated by the presence of elevated plasma GFAP and white matter disease. These findings highlight the potential utility of imaging and plasma biomarkers in the current landscape of therapeutics targeting dementia. HIGHLIGHTS: Perivascular spaces (PVS) and white matter hyperintensities (WMH) are imaging markers of small vessel disease. Plasma glial fibrillary protein acidic protein (GFAP) is a biomarker of astroglial injury. PVS, WMH, and GFAP are relevant in executive dysfunction from neurodegeneration. PVS's effect on executive function was mediated by GFAP and white matter disease.
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AIMS: This study examined serum cytochrome P450-soluble epoxide hydrolase (CYP450-sEH) oxylipins and depressive symptoms together in relation to cognitive performance in individuals with type 2 diabetes mellitus (T2DM). METHODS: Clinically cognitively normal T2DM individuals were recruited (NCT04455867). Depressive symptom severity was assessed using the Beck Depression Inventory-II (BDI-II; total scores ≤13 indicated minimal depressive symptoms and ≥ 14 indicated significant depressive symptoms). Executive function and verbal memory were assessed. Fasting serum oxylipins were quantified by ultra-high-performance liquid chromatography tandem mass-spectrometry. RESULTS: The study included 85 participants with minimal depressive symptoms and 27 with significant symptoms (mean age: 63.3 ± 9.8 years, 49 % women). In all participants, higher concentrations of linoleic acid derived sEH (12,13-dihydroxyoctadecamonoenoic acid; DiHOME) and CYP450 (12(13)-epoxyoctadecamonoenoic acid; EpOME) metabolites were associated with poorer executive function (F1,101 = 6.094, p = 0.015 and F1,101 = 5.598, p = 0.020, respectively). Concentrations of multiple sEH substrates interacted with depressive symptoms to predict 1) poorer executive function, including 9(10)-EpOME (F1,100 = 12.137, p < 0.001), 5(6)-epoxyeicosatrienoic acid (5(6)-EpETrE; F1,100 = 6.481, p = 0.012) and 11(12)-EpETrE (F1,100 = 4.409, p = 0.038), and 2) verbal memory, including 9(10)-EpOME (F1,100 = 4.286, p = 0.041), 5(6)-EpETrE (F1,100 = 6.845, p = 0.010), 11(12)-EpETrE (F1,100 = 3.981, p = 0.049) and 14(15)-EpETrE (F1,100 = 5.019, p = 0.027). CONCLUSIONS: Associations of CYP450-sEH metabolites and depressive symptoms with cognition highlight the biomarker and therapeutic potential of the CYP450-sEH pathway in T2DM.
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INTRODUCTION: Hypertension and diabetes are common cardiovascular risk factors that increase Alzheimer's disease (AD) risk. However, it is unclear whether AD risk differs in hypertensive individuals with and without diabetes. METHODS: Cognitively normal individuals (N = 11,074) from the National Alzheimer's Coordinating Center (NACC) were categorized as having (1) hypertension with diabetes (HTN+/DM+), (2) hypertension without diabetes (HTN+/DM-), or (3) neither (HTN-/DM-). AD risk in HTN+/DM+ and HTN+/DM- was compared to HTN-/DM-. This risk was then investigated in those with AD neuropathology (ADNP), cerebral amyloid angiopathy (CAA), cerebrovascular neuropathology (CVNP), arteriolosclerosis, and atherosclerosis. Finally, AD risk in HTN-/DM+ was compared to HTN-/DM-. RESULTS: Seven percent (N = 830) of individuals developed AD. HTN+/DM+ (hazard ratio [HR] = 1.31 [1.19-1.44]) and HTN+/DM- (HR = 1.24 [1.17-1.32]) increased AD risk compared to HTN-/DM-. AD risk was greater in HTN+/DM+ with ADNP (HR = 2.10 [1.16-3.79]) and CAA (HR = 1.52 [1.09-2.12]), and in HTN+/DM- with CVNP (HR = 1.54 [1.17-2.03]). HTN-/DM+ also increased AD risk (HR = 1.88 [1.30-2.72]) compared to HTN-/DM-. DISCUSSION: HTN+/DM+ and HTN+/DM- increased AD risk compared to HTN-/DM-, but pathological differences between groups suggest targeted therapies may be warranted based on cardiovascular risk profiles. HIGHLIGHTS: AD risk was studied in hypertensive (HTN+) individuals with/without diabetes (DM+/-). HTN+/DM+ and HTN+/DM- both had an increased risk of AD compared to HTN-/DM-. Post mortem analysis identified neuropathological differences between HTN+/DM+ and HTN+/DM-. In HTN+/DM+, AD risk was greater in those with AD neuropathology and CAA. In HTN+/DM-, AD risk was greater in those with cerebrovascular neuropathology.
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Alzheimer Disease , Atherosclerosis , Cerebral Amyloid Angiopathy , Diabetes Mellitus , Hypertension , Humans , Alzheimer Disease/epidemiology , Alzheimer Disease/pathology , Hypertension/complications , Hypertension/epidemiology , Diabetes Mellitus/epidemiologyABSTRACT
Importance: Increased white matter hyperintensity (WMH) volume is a common magnetic resonance imaging (MRI) finding in both autosomal dominant Alzheimer disease (ADAD) and late-onset Alzheimer disease (LOAD), but it remains unclear whether increased WMH along the AD continuum is reflective of AD-intrinsic processes or secondary to elevated systemic vascular risk factors. Objective: To estimate the associations of neurodegeneration and parenchymal and vessel amyloidosis with WMH accumulation and investigate whether systemic vascular risk is associated with WMH beyond these AD-intrinsic processes. Design, Setting, and Participants: This cohort study used data from 3 longitudinal cohort studies conducted in tertiary and community-based medical centers-the Dominantly Inherited Alzheimer Network (DIAN; February 2010 to March 2020), the Alzheimer's Disease Neuroimaging Initiative (ADNI; July 2007 to September 2021), and the Harvard Aging Brain Study (HABS; September 2010 to December 2019). Main Outcome and Measures: The main outcomes were the independent associations of neurodegeneration (decreases in gray matter volume), parenchymal amyloidosis (assessed by amyloid positron emission tomography), and vessel amyloidosis (evidenced by cerebral microbleeds [CMBs]) with cross-sectional and longitudinal WMH. Results: Data from 3960 MRI sessions among 1141 participants were included: 252 pathogenic variant carriers from DIAN (mean [SD] age, 38.4 [11.2] years; 137 [54%] female), 571 older adults from ADNI (mean [SD] age, 72.8 [7.3] years; 274 [48%] female), and 318 older adults from HABS (mean [SD] age, 72.4 [7.6] years; 194 [61%] female). Longitudinal increases in WMH volume were greater in individuals with CMBs compared with those without (DIAN: t = 3.2 [P = .001]; ADNI: t = 2.7 [P = .008]), associated with longitudinal decreases in gray matter volume (DIAN: t = -3.1 [P = .002]; ADNI: t = -5.6 [P < .001]; HABS: t = -2.2 [P = .03]), greater in older individuals (DIAN: t = 6.8 [P < .001]; ADNI: t = 9.1 [P < .001]; HABS: t = 5.4 [P < .001]), and not associated with systemic vascular risk (DIAN: t = 0.7 [P = .40]; ADNI: t = 0.6 [P = .50]; HABS: t = 1.8 [P = .06]) in individuals with ADAD and LOAD after accounting for age, gray matter volume, CMB presence, and amyloid burden. In older adults without CMBs at baseline, greater WMH volume was associated with CMB development during longitudinal follow-up (Cox proportional hazards regression model hazard ratio, 2.63; 95% CI, 1.72-4.03; P < .001). Conclusions and Relevance: The findings suggest that increased WMH volume in AD is associated with neurodegeneration and parenchymal and vessel amyloidosis but not with elevated systemic vascular risk. Additionally, increased WMH volume may represent an early sign of vessel amyloidosis preceding the emergence of CMBs.
Subject(s)
Alzheimer Disease , Amyloidosis , White Matter , Humans , Female , Aged , Adult , Male , Alzheimer Disease/diagnostic imaging , Alzheimer Disease/genetics , Alzheimer Disease/complications , White Matter/diagnostic imaging , White Matter/pathology , Longitudinal Studies , Cohort Studies , Cross-Sectional Studies , Magnetic Resonance Imaging , Amyloidosis/complications , Amyloidogenic ProteinsABSTRACT
Background Cardiovascular risk factors co-occur with one another, and little is known about the extent of their clustering and risk of Alzheimer disease (AD). We identify groups of cardiovascular risk factors in cognitively normal individuals and investigate between-group differences in incident AD and death. Methods and Results Cognitively normal individuals were recruited from the National Alzheimer's Coordinator Center. A latent class analysis was conducted with hypertension, hypercholesterolemia, heart condition, stroke, smoking history, diabetes, and high body mass index. Between-group differences in the incidence of AD, mortality, and mortality-adjusted AD were investigated. This study included 12 412 cognitively normal individuals (average follow-up, 65 months). Three groups were identified: (1) low probabilities of cardiovascular risk factors (reference; N=5398 [43%]), (2) hypertension and hypercholesterolemia (vascular-dominant; N=5721 [46%]), and (3) hypertension, hypercholesterolemia, diabetes, and high body mass index (vascular-metabolic; N=1293 [10%]). Both vascular groups were significantly older, had more men, were slightly less educated, and were slightly more cognitively impaired than the reference group (all P<0.05). However, only the vascular-metabolic group had a significantly younger age of death compared with the reference group (84.3 versus 88.7 years, P<0.001). Only the vascular-dominant group had a greater incidence of AD (odds ratio [OR], 1.30; P<0.001) compared with the reference group. Mortality was greater in the vascular-dominant (OR, 3.26; P<0.001) and vascular-metabolic groups (OR, 1.84; P=0.02). Mortality-adjusted AD was greater in the vascular-dominant (OR, 1.54; P=0.02) and vascular-metabolic groups (OR, 1.46; P=0.04). Conclusions Three distinct cardiovascular risk factor groups were identified in cognitively normal elderly individuals. Only the vascular-dominant group was associated with a greater incidence of AD. Selective mortality may contribute to the attenuated association between the vascular-metabolic group and incident AD.
Subject(s)
Alzheimer Disease , Cardiovascular Diseases , Diabetes Mellitus , Hypercholesterolemia , Hypertension , Male , Humans , Aged , Aged, 80 and over , Alzheimer Disease/epidemiology , Cardiovascular Diseases/epidemiology , Risk Factors , Hypercholesterolemia/epidemiology , Hypertension/epidemiology , Diabetes Mellitus/epidemiology , Heart Disease Risk FactorsABSTRACT
INTRODUCTION: Mild behavioral impairment (MBI) is characterized by later-life emergence of neuropsychiatric symptoms. Investigating its relationship with progression to Alzheimer's disease (AD) would provide insight on its importance as a predictor of AD. METHODS: Cognitively normal participants (N = 11,372) from the National Alzheimer's Coordinating Center were stratified by MBI status, using the Neuropsychiatric Inventory-Questionnaire. We investigated whether MBI and its domains were predictors of progression to clinically-diagnosed AD. MBI as a predictor of progression to neuropathology-confirmed AD was also investigated in those with neuropathological data. RESULTS: Six percent (N = 671) of participants progressed to AD. MBI (N = 2765) was a significant predictor of progression to clinically-diagnosed (hazard ratio [HR] = 1.75) and neuropathology-confirmed AD (HR = 1.59). MBI domains were also associated with clinically-diagnosed AD, with psychosis having the greatest effect (HR = 6.49). DISCUSSION: These findings support the biological underpinnings of MBI, emphasizing the importance of later life behavioral changes in dementia detection and prognostication.
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Alzheimer Disease , Cognitive Dysfunction , Humans , Alzheimer Disease/psychology , Cognitive Dysfunction/diagnosis , Disease Progression , Neuropsychological TestsABSTRACT
INTRODUCTION: Apathy is common in neurocognitive disorders (NCD) but NCD-specific diagnostic criteria are needed. METHODS: The International Society for CNS Clinical Trials Methodology Apathy Work Group convened an expert group and sought input from academia, health-care, industry, and regulatory bodies. A modified Delphi methodology was followed, and included an extensive literature review, two surveys, and two meetings at international conferences, culminating in a consensus meeting in 2019. RESULTS: The final criteria reached consensus with more than 80% agreement on all parts and included: limited to people with NCD; symptoms persistent or frequently recurrent over at least 4 weeks, a change from the patient's usual behavior, and including one of the following: diminished initiative, diminished interest, or diminished emotional expression/responsiveness; causing significant functional impairment and not exclusively explained by other etiologies. DISCUSSION: These criteria provide a framework for defining apathy as a unique clinical construct in NCD for diagnosis and further research.
Subject(s)
Apathy/physiology , Consensus , Delphi Technique , Expert Testimony , Neurocognitive Disorders/classification , Neurocognitive Disorders/diagnosis , Emotions , Humans , Motivation , Neurocognitive Disorders/psychologyABSTRACT
To identify knowledge gaps regarding new-onset agitation and impulsivity prior to onset of cognitive impairment or dementia the International Society to Advance Alzheimer's Research and Treatment Neuropsychiatric Syndromes (NPS) Professional Interest Area conducted a scoping review. Extending a series of reviews exploring the pre-dementia risk syndrome Mild Behavioral Impairment (MBI), we focused on late-onset agitation and impulsivity (the MBI impulse dyscontrol domain) and risk of incident cognitive decline and dementia. This scoping review of agitation and impulsivity pre-dementia syndromes summarizes the current biomedical literature in terms of epidemiology, diagnosis and measurement, neurobiology, neuroimaging, biomarkers, course and prognosis, treatment, and ongoing clinical trials. Validations for pre-dementia scales such as the MBI Checklist, and incorporation into longitudinal and intervention trials, are needed to better understand impulse dyscontrol as a risk factor for mild cognitive impairment and dementia.
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OBJECTIVE: Understanding the effects of benzodiazepines (BZDs) on maternal/fetal health remains incomplete despite their frequent use. This article quantifies the effects of antenatal BZD exposure on delivery outcomes. DATA SOURCES: Medline, PsycINFO, CINAHL, Embase, and the Cochrane Library were searched till June 30, 2018. STUDY SELECTION: English-language cohort studies comparing antenatal BZD exposure to an unexposed group on any delivery outcome were eligible. In all, 23,909 records were screened, 56 studies were assessed, and 14 studies were included. DATA EXTRACTION: Two reviewers independently assessed quality and extracted data. Estimates were pooled using random effects meta-analysis. Sub-analyses examined several potential moderators including timing of exposure. RESULTS: There were 9 outcomes with sufficient data for meta-analysis. Antenatal BZD exposure was significantly associated with increased risk of 6 outcomes initially: spontaneous abortion (pooled odds ratio = 1.86; 95% confidence interval [CI], 1.43 to 2.42), preterm birth (1.96; 95% CI, 1.25 to 3.08), low birth weight (2.24; 95% CI, 1.41 to 3.88), low Apgar score (2.19; 95% CI, 1.94 to 2.47), Neonatal Intensive Care Unit (NICU) admission (2.61; 95% CI, 1.64 to 4.14), and induced abortion (2.04; 95% CI, 1.23 to 3.40). There was significant heterogeneity between studies for most outcomes without consistent moderators. Birth weight (mean difference [MD]: -151.35 g; 95% CI, -329.73 to 27.03), gestational age (-0.49 weeks; 95% CI, -1.18 to 0.19), and small for gestational age (SGA; 1.42; 95% CI, 1.00 to 2.01) did not show significant associations although after adjusting for publication bias, gestational age, and SGA became significant, totaling 8 significant outcomes. CONCLUSIONS: Antenatal BZD exposure appears to be statistically associated with increased risk of several adverse perinatal outcomes. Although confounds cannot be ruled out, NICU admission does appear clinically relevant and consistent with the antidepressant literature.
Subject(s)
Antidepressive Agents/adverse effects , Benzodiazepines/adverse effects , Pregnancy Complications/psychology , Pregnancy Outcome , Premature Birth , Adult , Female , Humans , Infant, Newborn , Maternal Exposure/adverse effects , Maternal Exposure/statistics & numerical data , Pregnancy , Pregnancy Complications/drug therapy , Premature Birth/chemically induced , Prenatal Exposure Delayed Effects/chemically inducedABSTRACT
The endocannabinoid system has been a target of interest for agitation in Alzheimer disease (AD) because of potential behavioral effects and its potential impact on mechanisms implicated in AD such as oxidative stress (OS) and neuroinflammation. We explored whether serum markers of OS and neuroinflammation were associated with response to the cannabinoid nabilone in agitated patients with AD (N = 38). All participants were enrolled in a 14-week, double-blind, cross-over trial comparing nabilone to placebo (6 weeks each) with a 1-week washout between phases. Samples were collected at the start and end of each phase. The cross-sectional relationship agitation (Cohen Mansfield Agitation Inventory) and OS and inflammatory markers were investigated to select markers of interest. Significant markers were then explored for their relationship with response. The OS marker, 4-hydroxynonenal (4-HNE; F1, 35 = 6.41, P = .016), and the proinflammatory cytokine, tumor necrosis factor-α (TNF-α; F1, 29 = 3.97, P = .06), were associated with agitation severity, and TNF-α remained significantly associated (F2, 25 = 3.69, P = .04) after adjustment for cognition. In the placebo phase, lower baseline 4-HNE was associated with decreases in agitation severity only (b = 0.01, P = .01), while lower baseline TNF-α was associated with decreases in agitation severity in the nabilone phase only (b = 1.14, P = .045). Changes in 4-HNE were not associated with changes in agitation severity in either phase. In the nabilone phase, lower baseline TNF-α was associated with decreases in agitation severity (b = 1.14, P = .045), and decreases in TNF-α were associated with decreases in agitation severity (b = 1.12, P = .006). These findings suggest that OS and neuroinflammation may be associated with agitation severity, while nabilone may have anti-inflammatory effects.
Subject(s)
Alzheimer Disease/complications , Cognition/drug effects , Cytokines/therapeutic use , Dronabinol/analogs & derivatives , Oxidative Stress/physiology , Psychomotor Agitation/drug therapy , Aged , Biomarkers/blood , Dronabinol/therapeutic use , Female , Humans , Male , Psychomotor Agitation/complicationsABSTRACT
Agitation is a prevalent and difficult-to-treat symptom in patients with moderate-to-severe Alzheimer's disease (AD). Though there are nonpharmacological and pharmacological interventions recommended for the treatment of agitation, the efficacy of these are modest and not always consistent. Furthermore, the safety profiles of currently prescribed medications are questionable. Nabilone, a synthetic cannabinoid, has a distinct pharmacological profile that may provide a safer and more effective treatment for agitation, while potentially having benefits for weight and pain. Additionally, emerging evidence suggests nabilone may have neuroprotective effects. We describe a clinical trial investigating the safety and efficacy of nabilone for the treatment of agitation in patients with moderate-to-severe AD. This will be a double-blind, randomized cross-over study comparing 6 weeks of nabilone (0.5-2â¯mg) and placebo, with a 1-week washout preceding each phase. Study outcomes will be measured at baseline and end of treatment for each treatment phase. The primary outcome measure will be agitation as assessed by the Cohen-Mansfield Agitation Inventory. The secondary outcomes include safety, behaviour (Neuropsychiatric Inventory), cognition (standardized Mini Mental Status Exam and either Severe Impairment Battery or Alzheimer's disease Assessment Scale-Cognitive subscale) and global impression (Clinician's Global Impression of Change). Exploratory outcomes include pain (Pain Assessment in Advanced AD), nutritional status (Mini-Nutritional Assessment-Short Form), caregiver distress (NPI caregiver distress), and blood-based biomarkers. A safe and efficacious pharmacological intervention for agitation, with effects on pain and weight loss in patients with moderate-to-severe AD could increase quality-of-life, reduce caregiver stress and avoid unnecessary institutionalization and related increases in health care costs. CLINICAL TRIALS NUMBER: NCT02351882.
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BACKGROUND: Agitation is a prevalent and difficult-to-treat symptom of Alzheimer's disease (AD). The endocannabinoid system (ECS) has been a target of interest for the treatment of agitation. However, ECS signaling may interact with AD-related changes in brain cholesterol metabolism. Elevated brain cholesterol, reflected by reduced serum 24-S-hydroxycholesterol (24S-OHC), is associated with reduced membrane fluidity, preventing ligand binding to cannabinoid receptor 1. OBJECTIVE: To assess whether 24S-OHC was associated with agitation severity and response to nabilone. METHODS: 24S-OHC was collected from AD patients enrolled in a clinical trial on nabilone at the start and end of each phase. This allowed for the cross-sectional and longitudinal investigation between 24S-OHC and agitation (Cohen Mansfield Agitation Inventory, CMAI). Post-hoc analyses included adjustments for baseline standardized Mini-Mental Status Exam (sMMSE), and analyses with CMAI subtotals consistent with the International Psychogeriatric Association (IPA) definition for agitation (physical aggression and nonaggression, and verbal aggression). RESULTS: 24S-OHC was not associated with CMAI scores cross-sectionally or longitudinally, before and after adjusting for baseline sMMSE. However, 24S-OHC was associated with greater CMAI IPA scores at baseline (F(1,36)â=â4.95, pâ=â0.03). In the placebo phase only, lower 24S-OHC at baseline was associated with increases in CMAI IPA scores (bâ=â-35.2, 95% CI -65.6 to -5.0, pâ=â0.02), and decreases in 24S-OHC were associated with increases in CMAI IPA scores (bâ=â-20.94, 95% CI -57.9 to -4.01, pâ=â0.03). CONCLUSION: 24S-OHC was associated with agitation severity cross-sectionally, and longitudinally in patients with AD. However, 24S-OHC did not predict treatment response, and does not change over time with nabilone.
Subject(s)
Alzheimer Disease/psychology , Anti-Anxiety Agents/therapeutic use , Dronabinol/analogs & derivatives , Hydroxycholesterols/blood , Psychomotor Agitation/drug therapy , Aged, 80 and over , Alzheimer Disease/complications , Cross-Sectional Studies , Dronabinol/therapeutic use , Female , Humans , Hydroxycholesterols/metabolism , Longitudinal Studies , Male , Psychomotor Agitation/blood , Psychomotor Agitation/metabolism , Treatment OutcomeABSTRACT
OBJECTIVE: To investigate the efficacy and safety of nabilone for agitation in patients with moderate-to-severe Alzheimer's disease (AD). DESIGN: This 14-week randomized double-blind crossover trial compared nabilone to placebo (6 weeks each) with a 1-week washout between phases. SETTING: Patients were recruited from a long-term care facility and geriatric psychiatry clinics. PARTICIPANTS: Patients had AD (standardized Mini-Mental State Examination [sMMSE ≤24]) and agitation (Neuropsychiatric Inventory-Nursing Home version [NPI-NH]-agitation/aggression subscore ≥3). INTERVENTION: Nabilone (target 1-2 mg) versus placebo. MEASUREMENTS: The primary outcome was agitation (Cohen Mansfield Agitation Inventory [CMAI]). Secondary outcomes included NPI-NH total, NPI-NH caregiver distress, cognition (sMMSE and Severe Impairment Battery [SIB] or Alzheimer's Disease Assessment Scale of Cognition), global impression (Clinician's Global Impression of Change [CGIC]), and adverse events. RESULTS: Thirty-nine patients (mean ± SD ageâ¯=â¯87 ± 10, sMMSEâ¯=â¯6.5 ± 6.8, CMAIâ¯=â¯67.9 ± 17.6, NPI-NH totalâ¯=â¯34.3 ± 15.8, 77% male, nabilone doseâ¯=â¯1.6 ± 0.5 mg) were randomized. There were no crossover or treatment-order effects. Using a linear mixed model, treatment differences (95% CI) in CMAI (bâ¯=â¯-4.0 [-6.5 to -1.5], t(30.2)â¯=â¯-3.3, pâ¯=â¯0.003), NPI-NH total (bâ¯=â¯-4.6 [-7.5 to -1.6], t(32.9)â¯=â¯-3.1, pâ¯=â¯0.004), NPI-NH caregiver distress (bâ¯=â¯-1.7 [-3.4 to -0.07, t(33.7)â¯=â¯-2.1, pâ¯=â¯0.041), and sMMSE (bâ¯=â¯1.1 [0.1-2.0], t(22.6)â¯=â¯2.4, pâ¯=â¯0.026) all favored nabilone. However, in those who completed the SIB (nâ¯=â¯25) treatment differences favored placebo (bâ¯=â¯-4.6 [-7.3 to -1.8], t(20.7)â¯=â¯-4.8, pâ¯=â¯0.003). CGIC improvement during nabilone (47%) and placebo (23%) was not significantly different (McNemar's test, exact pâ¯=â¯0.09). There was more sedation during nabilone (45%) compared to placebo (16%) phases (McNemar's test, exact pâ¯=â¯0.02), but treatment-limiting sedation was not significantly different (McNemar's test, exact pâ¯=â¯0.22). CONCLUSIONS: Nabilone may be an effective treatment for agitation. However, sedation and cognition should be closely monitored.
Subject(s)
Aggression/drug effects , Alzheimer Disease/drug therapy , Antipsychotic Agents/therapeutic use , Dronabinol/analogs & derivatives , Aged , Aged, 80 and over , Cognition , Double-Blind Method , Dronabinol/therapeutic use , Female , Homes for the Aged , Humans , Male , Nursing Homes , Psychiatric Status Rating Scales , Treatment OutcomeABSTRACT
OBJECTIVE: Apathy and depression have each been associated with an increased risk of conversion from mild cognitive impairment (MCI) to Alzheimer disease (AD).These symptoms often co-occur and the contribution of each to risk of AD is not clear. METHODS: National Alzheimer's Coordinating Center participants diagnosed with MCI at baseline and followed until development of AD or loss to follow-up (n = 4,932) were included. The risks of developing AD in MCI patients with neuropsychiatric symptoms (NPS) (apathy only, depression only, or both) were compared to that in those without NPS in a multivariate Cox regression survival analysis adjusting for baseline cognitive impairment, years of smoking, antidepressant use, and AD medication use. RESULTS: Thirty-seven percent (Nâ¯=â¯1713) of MCI patients developed AD (median follow-up 23 months). MCI patients with both apathy and depression had the greatest risk (hazard ratio [HR]â¯=â¯1.37; 95% confidence interval [CI]: 1.17-1.61; p < 0.0001; Wald χ2â¯=â¯14.70; dfâ¯=â¯1). Those with apathy only also had a greater risk (HRâ¯=â¯1.24; 95% CI: 1.05-1.47; pâ¯=â¯0.01; Wald χ2â¯=â¯6.22; dfâ¯=â¯1), but not those with depression only (HRâ¯=â¯1.08; 95% CI: 0.95-1.22; p=0.25; Wald χ2â¯=â¯1.30; dfâ¯=â¯1). Post-hoc analyses suggested depression may exacerbate cognitive decline in MCI patients with apathy (odds ratioâ¯=â¯0.70; 95% CI 0.52-0.95; pâ¯=â¯0.02; Wald χ2â¯=â¯5.28; dfâ¯=â¯1), compared to those without apathy. CONCLUSION: MCI patients with apathy alone or both apathy and depression are at a greater risk of developing AD compared to those with no NPS. Interventions targeting apathy and depression may reduce risk of AD.
Subject(s)
Alzheimer Disease/diagnosis , Apathy/physiology , Cognitive Dysfunction/physiopathology , Depression/physiopathology , Disease Progression , Aged , Aged, 80 and over , Alzheimer Disease/epidemiology , Cognitive Dysfunction/epidemiology , Comorbidity , Depression/epidemiology , Female , Humans , Longitudinal Studies , Male , Prognosis , RiskABSTRACT
OBJECTIVE: This meta-analysis investigated the efficacy of cannabinoids on agitation and aggression in patients with Alzheimer's disease (AD). DATA SOURCES: Electronic records up to August 2018 were searched from MEDLINE, EMBASE, and PsycINFO. Search terms included Alzheimer's disease, agitation, aggression, and cannabinoids. STUDY SELECTION: Double-blind, placebo-controlled studies investigating the effect of cannabinoids on agitation in patients with AD were included. Of the 1,336 records returned, 123 were reviewed and 6 (N = 251 participants) were included. DATA EXTRACTION: Data on demographics, study setting, trial length, intervention, outcomes, and dropouts were extracted. RESULTS: There was no effect of cannabinoids as a group on agitation (standard mean difference: -0.69, P = .10), though there was significant heterogeneity (χ²6 = 43.53, P < .00001, I² = 86%). There was a trend for greater difference in agitation with synthetic cannabinoids over tetrahydrocannabinol (χ²1 = 3.05, P = .08). Cannabinoids had a larger effect on agitation with greater cognitive impairment (B = 0.27, t6 = 2.93, P = .03). Cannabinoids did not change overall neuropsychiatric symptoms or body mass index (BMI). However, there was a significant difference in patients with a lower BMI compared to patients with a higher BMI (χ²1 = 4.63, P = .03). Sedation was significantly greater with cannabinoids compared to placebo (risk ratio = 1.73, P = .04), but there were no differences in the occurrence of adverse events or dropouts due to an adverse event between treatment groups. CONCLUSIONS: The efficacy of cannabinoids on agitation and aggression in patients with AD remains inconclusive, though there may be a signal for a potential benefit of synthetic cannabinoids. Safety should be closely monitored as cannabinoid treatment was associated with increased sedation.
Subject(s)
Aggression/drug effects , Alzheimer Disease/drug therapy , Cannabinoids/therapeutic use , Psychomotor Agitation/drug therapy , Alzheimer Disease/complications , Humans , Psychomotor Agitation/complicationsABSTRACT
Apathy is a prevalent and problematic neuropsychiatric symptom in those with dementia that is emerging as a treatment target, necessitating accurate assessment. While many apathy scales are available, not all have been developed for use exclusively in dementia, and psychometric properties may vary across different populations. This systematic review aimed to provide an overview of the psychometric properties of apathy scales used in Alzheimer's disease (AD) and related dementias, as well as rate the methodological quality of supporting studies. In addition, for those scales identified, performance in clinical trials was reviewed. A search was conducted through Medline, Psychinfo, Embase, Cochrane Central Register of Controlled Trials, and Cochrane Database of Systematic Reviews. Articles that reported psychometric properties of an apathy scale in an AD or mixed dementia population were included. Of 15 articles, the methodological quality ratings of the studies ranged from adequate to excellent. Three clinical trials and two pooled analyses of clinical trials were included that used apathy scales evaluated in this review. Three scales emerged. The Neuropsychiatric Inventory apathy subscale (NPI-apathy) and the Apathy Evaluation Scale (AES) had the greatest number of studies evaluating psychometric properties and were also used in the clinical trials and have shown sensitivity to change. The Dementia Apathy Interview and Rating demonstrated excellent values of internal consistency, validity, and reliability for use in an AD population. Future research should address comparative scale performance and assess ability to distinguish subtypes of apathy. Validation may include evaluation of performance against specific imaging defined deficits.
Subject(s)
Apathy/physiology , Dementia/psychology , Humans , Psychometrics , Reproducibility of ResultsABSTRACT
Apathy is among the most prevalent neuropsychiatric symptom experienced in Parkinson's disease (PD) and can be assessed with a variety of scales. To identify which scale is most suitable for apathy assessment in PD, the psychometric properties of each scale and its sensitivity to change were analyzed. The methodological quality of the studies ranged from adequate to excellent. The Lille Apathy Rating Scale demonstrated consistently favorable psychometric properties and was used in two of four clinical trials found. The Starkstein Apathy Scale was the only other scale used in clinical trials. Further work is necessary to develop a gold standard for assessing apathy in PD.
Subject(s)
Apathy , Parkinson Disease/psychology , Psychiatric Status Rating Scales , Humans , Parkinson Disease/diagnosis , PsychometricsABSTRACT
INTRODUCTION: Agitation is one of the most challenging neuropsychiatric symptoms to treat in Alzheimer's disease and has significant implications for patient and caregiver. A major source of difficulty in identifying safe and effective treatments for agitation is the lack of validated biomarkers. As such, patients may not be appropriately targeted, and biological response to pharmacotherapy cannot be adequately monitored. METHODS: This systematic review aimed to summarize evidence on the association between biomarkers and agitation/aggression in patients with Alzheimer's disease, utilizing the National Institute on Aging-Alzheimer's Association Research Framework and the Biomarkers, EndpointS, and other Tools Resource of the Food and Drug Association-National Institutes of Health Biomarker Working Group. RESULTS: This review identified six classes of biomarkers (neuropathological, neurotransmitter, neuroimaging, apolipoprotein E (APOE) genotype, inflammatory, and clusterin) associated with agitation/aggression, which were mostly diagnostic in nature. DISCUSSION: Future studies should investigate the predictive, prognostic, and monitoring capacity of biomarkers to provide insight into the longitudinal course of agitation/aggression, as well as predict and monitor biological response to a pharmacological intervention.
Subject(s)
Aggression , Alzheimer Disease/diagnosis , Psychomotor Agitation/diagnosis , Aggression/physiology , Alzheimer Disease/genetics , Alzheimer Disease/physiopathology , Alzheimer Disease/psychology , Biomarkers/metabolism , Humans , Psychomotor Agitation/genetics , Psychomotor Agitation/physiopathologyABSTRACT
BACKGROUND: Despite the high prevalence of apathy in Alzheimer's disease (AD), and its harmful effects, there are currently no therapies proven to treat this symptom. Recently, a number of pharmacological therapies have been investigated as potential treatments for apathy in AD. OBJECTIVES: Objective 1: To assess the safety and efficacy of pharmacotherapies for the treatment of apathy in Alzheimer's disease (AD).Objective 2: To assess the effect on apathy of pharmacotherapies investigated for other primary outcomes in the treatment of AD. SEARCH METHODS: We searched the Specialized Register of the Cochrane Dementia and Cognitive Improvement Group (ALOIS), MEDLINE, Embase, CINAHL, PsycINFO, LILACS, ClinicalTrials.gov and the World Health Organization (WHO) portal, ICTRP on 17 May 2017. SELECTION CRITERIA: Eligible studies were double-blind, randomized, placebo-controlled trials (RCTs) investigating apathy as a primary or secondary outcome in people with AD. DATA COLLECTION AND ANALYSIS: Three review authors extracted data. We assessed the risks of bias of included studies using Cochrane methods, and the overall quality of evidence for each outcome using GRADE methods. We calculated mean difference (MD), standardized mean difference (SMD) or risk ratio (RR) with 95% confidence intervals on an intention-to-treat basis for all relevant outcome measures. MAIN RESULTS: We included 21 studies involving a total of 6384 participants in the quantitative analyses. Risk of bias is very low to moderate. All studies reported appropriate methods of randomization and blinding. Most studies reported appropriate methods of allocation concealment. Four studies, three with methylphenidate and one with modafinil, had a primary aim of improving apathy. In these studies, all participants had clinically significant apathy at baseline. Methylphenidate may improve apathy compared to placebo. This finding was present when apathy was assessed using the apathy evaluation scale (AES), which was used by all three studies investigating methylphenidate: MD -4.99, 95% CI -9.55 to -0.43, n = 145, 3 studies, low quality of evidence, but not when assessed with the neuropsychiatric inventory (NPI)-apathy subscale, which was used by two of the three studies investigating methylphenidate: MD -0.08, 95% CI -3.85 to 3.69, n = 85, 2 studies, low quality of evidence. As well as having potential benefits for apathy, methylphenidate probably also slightly improves cognition (MD 1.98, 95% CI 1.06 to 2.91, n = 145, 3 studies, moderate quality of evidence), and probably improves instrumental activities of daily living (MD 2.30, 95% CI 0.74 to 3.86, P = 0.004, n = 60, 1 study, moderate quality of evidence), compared to placebo. There may be no difference between methylphenidate and placebo in the risk of developing an adverse event: RR 1.28, 95% CI 0.67 to 2.42, n = 145, 3 studies, low quality of evidence. There was insufficient evidence from one very small study of modafinil to determine the effect of modafinil on apathy assessed with the FrSBe-apathy subscale: MD 0.27, 95% CI -3.51 to 4.05, n = 22, 1 study, low quality of evidence. In all other included studies, apathy was a secondary outcome and participants were not selected on the basis of clinically significant apathy at baseline. We considered the evidence on apathy from these studies to be indirect and associated with publication bias. There was low or very low quality of evidence on cholinesterase inhibitors (ChEIs) (six studies), ChEI discontinuation (one study), antipsychotics (two studies), antipsychotic discontinuation (one study), antidepressants (two studies), mibampator (one study), valproate (three studies) and semagacestat (one study). AUTHORS' CONCLUSIONS: Methylphenidate may demonstrate a benefit for apathy and may have slight benefits for cognition and functional performance in people with AD, but this finding is associated with low-quality evidence. Our meta-analysis is limited by the small number of studies within each drug class, risk of bias, publication bias, imprecision and inconsistency between studies. Additional studies should be encouraged targeting people with AD with clinically significant apathy which investigate apathy as a primary outcome measure, and which have a longer duration and a larger sample size. This could increase the quality of evidence for methylphenidate, and may confirm whether or not it is an effective pharmacotherapy for apathy in AD.