Mild Cognitive Impairment (MCI) Exam 3 PDF

3.3 path cognitive changes pathological aging for the CNS : 3 Ds focus on: - depression - delirium - dementia spectrum of dementia - early changes identified as mild cognitive impairment (MCI). - progression towards cognitive diseases possible c...

3.3 path cognitive changes pathological aging for the CNS : 3 Ds focus on: - depression - delirium - dementia spectrum of dementia - early changes identified as mild cognitive impairment (MCI). - progression towards cognitive diseases possible continued accelerated aging processes. mild cognitive impairment (MCI) - precursor to dementia. - can be: - arrested. - reversed in some individuals presenting MCI. course of cognitive changes w age cognition in older adults normal changes - modest decline in short-term memory. - continued decline in processing speed. - verbal intelligence and personality remain stable. impact of accelerated aging - rapid and steep decline towards mild cognitive impairment (MCI) or cognitive disease. improving cognitive fitness strategies: - physical activity. - nutrition. - engagement in cognitive activities. benefits of cognitive fitness - increases cognitive reserve. - maintains fxn and health. diagnosis of mild cognitive impairment (MCI) - signifies significant loss in cognitive fitness. - potential swift progression to cognitive disease. mild cognitive impairment Definition: “a transitional zone between normal aging and dementia” and is a “symptomatic predementia range of cognition and function... and is not normal” Jekel K et al., 2015 & Albert MS et al., 2011 60 yrs: prevalence is low ^ 1 to 6.7 % rates increases w age to about 25% by age 85  contributors to mild cognitive impairment causes of mild cognitive impairment (MCI) - no single cause; multiple variables involved contributors: - health status - socioeconomic determinants of health - gender or genetic predisposition negative contributors - HTN or vascular pathology - brain infarction - altered lipid metabolism - environment - medication - illness - trauma mitigators - higher level of education - antidepressant therapies - statins DSM-5 diagnostic criteria mild neurocognitive disorder - moderate alcohol consumption practice guideline for MCI - cholinergic therapies - anti-inflammatory agents diagnostic criteria for mild cognitive impairment impact of lifestyle (MCI) by Albert et al. altered by: - concern regarding a change in cognition. - diet - impairment in one or more cognitive domains: - physical activity - memory - executive fxn more practice guidelines for MCI - attention practice guidelines by Peterson et al. - language aim: guidelines for mild cognitive - visual spatial skills impairment (MCI). - preservation of independence in functional recommendation: weaning from abilities (e.g., paying bills, preparing meals). medications contributing to cognitive dx: impairment if possible. - excludes presence of dementia. pharmacological tx types of mild cognitive impairment status: amnestic: - no approved pharmacological tx for - involves memory loss. MCI. non-amnestic: - none shown effective for - primarily involves attention. prevention. clock drawing test benefits of exercise - comparison across stages: types of exercise: - healthy adult - aerobic. - mild cognitive impairment (MCI). - strength training. - late alzheimer's disease. - combined training. observations: studies' findings: in MCI: - prevents declines in cognitive fxn - general structure of the clock present. in individuals w normal fxn - altered spacing of numbers. exercise recommendations for MCI - imprecise or inaccurate hands. frequency: - at least two times a week. duration: - at least 6 months. goal: - prevent further decline towards dementia. effect on training on MCI meta-analysis by Meng et al., 2022 aim: impact of interventions on preventing progression of mild cognitive impairment (MCI) types of Interventions studied - cognitive training - physical therapy - physical activity alone - no training (control group) findings - combined cognitive and physical training: - + effects on global cognition compared to control group - +effects on memory compared to physical activity alone or control - + effects on executive fxn compared to all other groups definition of cognitive training mental exercises to improve cognition: - memory - executive fxn - processing speed. - visual spatial perception also known as: - brain games. - cogniSize. - neurobics. which training? PT and mitigating mild cognitive impairment (MCI) progression - importance of physical activity in managing MCI progression. optimal exercise types systematic review by Huang et al., 2022 -examined efficacy of exercise interventions on cognitive fxn findings: - resistance exercise: - highest probability to slow cognitive decline - particularly beneficial for those with cognitive dysfxn (e.g., dementia) multi-component exercise: - most promising for neuroprotective effects - effective in preventing global cognitive loss and enhancing executive fxn in MCI - combo of any 2 types of exercise: - resistance training - balance training - aerobic training impact on memory resistance training: - higher impact on memory in MCI effectiveness of mind-body exercises - tai Chi, yoga, dance: - not shown to be more beneficial overall compared to multi-component or resistance training progression of MCI impact of physical activity - potential to reverse or halt progression of mild cognitive impairment (MCI) progression of mild cognitive impairment (MCI) - some cases progress to dementia. statistics on progression - 10%-15% of individuals with MCI progress to alzheimer's disease or other dementia per year - 55%-65% eventually progress to some form of dementia types of MCI - amnestic MCI variant: - progresses to dementia at a ratio of 3 to one compared to other variants Summary Mild cognitive impairment presents with decreased cognitive function with intact functional independence Exercise alone has significant impact on slowing cognitive decline  3.4 into to dementia DSM-5 diagnostic criteria: major neurocognitive disorder diagnostic criteria for dementia memory impairment: - difficulty learning new info or recalling previously learned info presence of one or more of: - aphasia (language impairment). - apraxia (inability to execute motor activities). - agnosia (failure to recognize or identify objects despite intact sensory fxn). - disturbance in executive fxn (e.g., planning, organizing). fxn impairment - significant decline in social or occupational fxning delirium and dementia relationship: - not exclusive; can occur concurrently. - overlap can lead to misdx or lack of dx. types of dementia dementia overview - umbrella term for sxs related to cognitive impairment major types of dementia alzheimer's disease: - most common cause vascular Dementia: - second most common lewy body dementia - frontotemporal dementia less common types - prion diseases (e.g., Creutzfeldt-Jakob disease). - neurodegenerative diseases associated w: - parkinson's - chronic traumatic encephalopathy (CTE) vascular dementia definition and epidemiology - second most common type of dementia. - associated w vascular comorbidities: - HTN - atrial fibrillation. - stroke. - diabetes. - smoking. clinical presentation distinguishing features from alzheimer's disease - abrupt and stepwise symptom onset - often associated w minor strokes or small vessel disease - cumulative cognitive decline over time.  affected fxns - memory. - abstract thinking. - judgment. - attention. - complex activities. variable fxnal deterioration - selective based on affected vasculature behavioral changes - altered impulse control - change in personality - emotional ability - depression - apathy vascular dementia: imaging vascular dementia characteristics - affected brain regions - more common in frontal lobes than temporal lobes cognitive performance compared to alzheimer's disease - poorer performance in: - verbal fluency - perseveration - abstract thinking better recall and memory compared to Alzheimer's disease neuroimaging findings - MRI: - detects lacunar infarcts due to chronic reduced blood flow - PET scan interpretation: - red indicates more active areas. - green indicates less active areas. comparison with Alzheimer's Disease on neuroimaging - alzheimer's disease: - increased frontal lobe activity (red). - decreased parietal and temporal lobe activity (green). vascular dementia: - multiple white areas on MRI (indicating lacunar infarcts). - increased parietal and temporal lobe activity (PET scan). - decreased frontal lobe activity (PET scan). vascular dementia: pathophysiology pathogenesis of vascular dementia differentiation from other dementias - related to stroke pathogenesis - combination of modifiable and non-modifiable risk factors stroke mechanism - thrombotic or embolic stroke. - blocked blood supply to brain region. - leads to hypoperfusion. cascade of effects - oxidative stress. - endothelial dysfxn - neuronal dysfxn - vascular cognitive impairment modifiable risk factors - importance in reducing stroke risk: - smoking cessation - diet management - physical activity management of comorbidities aimed at preventing: - HTN - diabetes - hyperlipidemia lewy body dementia lewy body dementia (LBD) overview association with parkinsonism - commonly diagnosed alongside PD pathophysiology - cause: - buildup of alpha-synuclein protein (Lewy bodies) inside neuron nuclei result: - neuronal degeneration in cortex or brainstem. genetic links - associated genes: - PARK11 - full life of protein genes distribution of alpha-synuclein - throughout the brain - accumulation in basal ganglia: - leads to dopamine degradation - contributes to neuronal death clinical ex robin williams: - initially diagnosed with PD - later found to have Lewy body dementia (LBD). - tragic outcome: suicide. lewy body dementia clinical presentation motor sx’s of lewy body dementia (LBD) - decreased effective use of dopamine in basal ganglia - parkinsonian motor sx’s: - stiffness - tremor - poor coordination - difficulty walking non-motor sx’s of LBD distribution of lewy bodies - accumulation throughout the brain  associated sx - recurrent visual hallucinations (hallmark sx) - progressive cognitive decline: - fluctuations in alertness and attention - poor executive fxn - mood changes - memory impairment imaging of lewy body imaging techniques for differential diagnosis DAT Scan (dopamine transporter scan) purpose: - assess dopamine uptake in the brain comparison: - normal healthy individual: - brightness in basal ganglia (normal dopamine use) alzheimer's disease: - similar brightness in basal ganglia (normal dopamine use) lewy body dementia: - decreased or altered dopamine processing in basal ganglia MRI Findings comparison: lewy body dementia: - lack of atrophy in medial temporal lobe alzheimer's disease: - atrophy in medial temporal lobe PET Imaging observation: lewy body dementia: - decreased use of occipital lobe (yellow color) - potential correlation with visual hallucinations normal controls: - dark orange color in occipital lobe (normal activity) frontotemporal dementia frontotemporal dementia (FTD) overview association w PD - second most frequent cause of early onset dementia incidence: - 15 to 22 cases per 100,000 bw ages 45 to 65 pathology - neurodegeneration: - in frontal and temporal lobes etiology - unknown etiology - genetic component: - 30 to 50% of cases pathophysiology - neuronal loss - astrocytic gliosis - abnormalities in specific proteins: - tau. - RNA-DNA binding proteins variants of frontotemporal dementia classification of Frontotemporal Dementia (FTD) - 3 main variants: - behavioral variant - non-fluent (primary progressive aphasia) variant - semantic variant behavioral variant characteristics: - disinhibition - socially inappropriate behaviors - apathy - loss of empathy - preserved memory and visual spatial fxn non-fluent (primary progressive aphasia) variant characteristics: - preserved social skills and personalities. - effortful speech. - impaired comprehension semantic variant characteristics: - primary progressive aphasia - circumlocutory speech - impaired word finding - tendency to ramble imaging of frontotemporal dementia comparison of frontotemporal dementia (FTD) and alzheimer's disease brain areas affected FTD: - targets frontal and temporal lobes. alzheimer's disease: - Impacts parietal and temporal lobes. beta amyloid presence - alzheimer's disease: - heightened presence of beta amyloid proteins. - FTD: - beta amyloid proteins less prominent or absent. MRI findings FTD: - lack of volume loss in parietal and temporal lobes. - no cortical atrophy in frontal lobe. PET Scanning: - decreased or green brain activity confined to frontal lobes. Summary Dementia characterizes substantial cognitive impairment with loss of functional independence Types of dementia can be differentiated by neuroanatomical pathophysiology and clinical presentation 1. Alzheimer’s disease 2. Vascular dementia 3. Lewy body dementia 4. Frontotemporal dementia