Feasibility of treating mild cognitive impairment with cholinesterase inhibitors

Neuropathology and treatment of Alzheimer disease: did we lose the forest for the trees?

Although amyloid-beta-containing senile plaques and phospho-tau containing neurofibrillary tangles are hallmark lesions of Alzheimer disease (AD), neither is specific for AD, nor even a marker of AD. Rather, they are empirical lesions that require close correlation with age and clinical signs for optimal interpretation. In essence, these lesions represent the effect rather than the cause of disease. In this review, we discuss diagnostic criteria for AD, the relationship between pathology, pathogenesis and multiple treatment approaches that have so far been disappointing, including those that presume to address pathological lesions. An acceptance that lesion-based therapies do not address etiology or rate-limiting pathogenic factors is probably necessary for the best chance of significant advances that have thus far been elusive.

Comorbidities and cognitive functioning: implications for nursing research and practice

Optimal cognitive functioning is necessary to successfully negotiate one's environment, yet medical conditions can interfere with brain health, thus negatively impacting cognitive functioning. Such comorbidities include hypertension, heart disease, diabetes, depression, and HIV, as well as others. The physiological properties of these comorbidities can reduce one's cognitive reserve and limit one's cognitive efficiency. This article provides an overview of a few common comorbidities known to affect cognitive functioning and addresses ways in which cognitive functioning may be ameliorated and protected or mitigated in lieu of cognitive declines in such clinical populations. Implications for nursing practice and research are posited.

Cognitive Remediation Therapies for Older Adults

Among older adults, 20%-56% report having cognitive problems, and such cognitive complaints frequently correspond to actual neuropsychological impairment. The loss of cognitive abilities can be frustrating and frightening and can have a negative impact on instrumental activities of daily living and quality of life. Cognitive remediation interventions have been shown to be successful in improving mental function in older adults in many situations and may increase the number of everyday activities they are able to carry out. Nurses, given their direct contact with older adult patients, are able to inquire about or observe cognitive loss, make appropriate referrals, and emphasize steps such as cognitive remediation and other interventions that promote successful cognitive aging.

MRI confirms mild cognitive impairments prodromal for Alzheimer's, vascular and Parkinson-Lewy body dementias

OBJECTIVES

MRI assessments were correlated with serial Combined Mini-Mental Cognitive Capacity Screening Examinations (CMC). Vascular-MCI (VMCI), Neurodegenerative MCI (NMCI) and Parkinson-Lewy body MCI (PLB-MCI) were compared during conversions to dementia. Mild cognitive impairments (MCI) are identifiable prodromes for all dementia subtypes. MRI abnormalities are characterized among MCI subjects prodromal for dementia of Alzheimer's disease (DAT), vascular dementia (VaD) and Parkinson-Lewy body dementia (PLBD).

METHODS

Aging volunteers (n=166) were recruited from ongoing longitudinal studies of aging, stroke, cerebrovascular disease and dementia. Cognitively normal (CN, n=52), MCIs of neurodegenerative (N-MCI, n=30), vascular (V-MCI, n=35) and Parkinson-Lewy Body (PLB-MCI, n=8) subtypes, plus converted DAT (n=19), VaD (n=17) and PLBD (n=5) were all diagnosed according to established protocol recommendations. Cerebral MRI abnormalities were likewise intercorrelated utilizing quantitative volumetric measurements.

RESULTS

V-MCI and converted VaD showed extensive leukoaraiosis with more lacunar infarcts than subjects with N-MCI or PLB-MCI. N-MCI, prodromal for DAT, showed medial temporal atrophy, greater enlargement of temporal horns, and fewer vascular lesions. PLB-MCI, prodromal for PLBD, displayed third ventricular enlargement greater than N-MCI and V-MCI, with similar but less severe atrophy of medial temporal lobe than N-MCI and fewer vascular lesions than V-MCI. Cognitive Impairments due to PLB with vascular features (V-PLB-CI) showed more lacunar and microvascular lesions involving both white matter and basal ganglia with greater frontal horn enlargement.

CONCLUSIONS

This study confirms different MCI subtypes prior to conversion to different dementias listed, recognizable by specific MRI abnormalities.

Addressing risk factors of cognitive impairment in adults aging with HIV: a social work model

With advances in life-extending medications and later- life infections, the number of older adults with HIV is increasing. Unfortunately, the synergistic effects of aging with HIV may place many people at risk of developing cognitive impairments which can disrupt everyday functioning. Fortunately, cognitive reserve may be maintained, or in some cases improved, by taking action to prevent or mitigate such loss. Preventative and treatment strategies that support biopsychosocial aspects of cognition include reducing alcohol and substance use; improving nutrition; diminishing the effects of comorbidities; increasing social contact; reducing depression and stress levels; engaging in cognitively stimulating activities; applying cognitive remediation therapies; and incorporating psychopharmacological interventions. Such strategies can improve the physiological integrity and health of the brain, thus supporting neuroplasticity and increasing cognitive reserve. Social workers are in a favorable position to recognize cognitive decline in clients and recommend or administer solutions to address such problems. A model for social workers advocating for older clients with HIV who have cognitive problems is provided.

MRI identifies MCI subtypes: vascular versus neurodegenerative

As life expectancy increases worldwide, pandemics of cognitive impairment and dementia are emerging as major public health problems. Mild cognitive impairment (MCI), prodromal for dementia, is a descriptive term used for those clinical states showing early and subtle cognitive decline among the elderly, preceding the dementias. Psychometric screening combining Mini-Mental Status (MMSE) and Cognitive Capacity Screening (CCSE) Examinations, when combined now called CMC with C standing for Combined, M for MMSE, and C for CCSE, confirms diagnosis of MCI. Individuals identified with MCI are at increased risk for dementia of Alzheimer's type (DAT), vascular dementia (VAD) and other rare neurodegenerative dementias, including Lewy body dementia (LBD), fronto-temporal dementia (FTD) and Parkinson's disease dementia (PDD). Depending on different clinical compositions of cohorts studied, and MCI criteria used, between 19% and 50% of MCI progress to dementia within 3-5 years, two thirds to Alzheimer's (DAT) and one third to vascular types (VAD) in the United States. Not all Parkinsonians become demented, but PDD develops in 20-30%, however, PDD subjects were excluded from the present study, as were LBD and FTD. The incidence of MCI in those over age 70, with confirmed cognitive declines when tested 2 years later, is around 23%, but some spontaneously improve.

Age-related mild cognitive deficit: a ready-to-use concept?

For better management of mild cognitive impairment in elderly patients, clinicians should be provided with instruments to detect early changes and predict their progression. To define this cognitive status between optimal and pathological aging, many concepts have been proposed, which actually describe various conditions and provide more or less precise criteria, leaving room for variable implementation. As a consequence, application of these criteria gave highly variable prevalence rates, Neuropathological studies indicate that the different criteria have variable power in detecting incipient Alzheimer's disease (AD) and suggest that the transition between mild cognitive impairment and ÀD is not merely quantitative. Follow-up studies have produced, according to the criteria used, a 2.5% to 16,6% annual rate for progression toward dementia, and have also shown that the criteria differ in their stability and predictive power. Baseline cognitive performances have some predictive value, but are difficult to apply in first-line medicine. Investigational techniques (structural and functional imaging, magnetic resonance spectroscopy, magnetization transfer imaging, cerebrospinal fluid neuro-chemistry, and apolipoprotein E genotype) are promising tools in the early diagnosis of AD, which remains the most frequent type of dementia in elderly people and probably the most frequent type developed by patients with mild cognitive deficit. The final goal is to offer early treatment to those patients who will evolve towards dementia, once they can be identified, in the case of AD, recent findings question the adequacy of cholinergic replacement therapies. In its current state, the criteria for mild cognitive deficit are hardly transferable to first-line medicine. However, disseminating the concept could help increase the sensitivity of general practitioners to the importance of cognitive complaints and signs in their elderly patients.

Longitudinal analysis of abnormal domains comprising mild cognitive impairment (MCI) during aging

Research directed towards early diagnosis and therapy of dementia demands rapid identification of prodromal mild cognitive impairment (MCI). A longitudinal study was designed to clarify whether different domains of cognitive impairment, tested by Mini-Mental State Examination (MMSE), help predict dementia. After 3.74+/-2.94 years of follow-up among 291 cognitively normative volunteers, 73 developed MCI. During the next 3.88+/-3.01 years of MCI follow-up, 47.9% of MCI developed dementia of Alzheimer's type (DAT), 20.5% of MCI developed vascular dementia (VaD) and 31.5% maintained persistent MCI at the time of data analysis. Total MMSE and subtest scores analyzed at MCI onset showed significant differences for serial seven subtest scores between DAT and persistent MCI (P<0.05). Rates of change in subtests of orientation and memory and total MMSE scores predicted DAT (P<0.01). Decreasing orientation and total MMSE scores predicted VaD conversion rates of MCI to DAT at 2 years were 20.06% among single-domain MCI versus 41.7% for multi-domain MCI (P<0.05). Subjects with MCI often have impaired cognitive domains other than memory and show rapid deterioration, which predicts DAT. VaD sometimes mimics DAT with subtle cognitive impairment appearing before onset of dementia.