Equilibrium and limb coordination in mild cognitive impairment and mild Alzheimer's disease.

OBJECTIVE: To examine changes in equilibrium and limb coordination in normal aging, mild cognitive impairment, and moderate cognitive impairment associated with early probable Alzheimer's disease (AD), by means of parametric clinical measures. DESIGN: Case series SETTING: Out-patient clinic. PARTICIPANTS: A consecutive sample of 365 community-residing ambulatory volunteers (137 men, 228 women; mean age 70.4 +/- 9.4 years; mean educational attainment 14.6 +/- 3.1 years), who were followed in an ongoing longitudinal study of aging and AD, comprising cognitively intact individuals, persons with mild cognitive impairment, and patients with mild AD. MEASUREMENTS: For general magnitude of cognitive function, the Global Deterioration Scale (GDS). For cognition, the Mini-Mental State Examination (MMSE). Equilibrium was assessed with parametric measurements of single leg stance (SLS) and tandem walking (TW). Limb coordination was assessed with parametric measurements of foot tapping (FT), alternating pronation and supination (PS), and sequential finger to thumb tapping (FTH). MAIN RESULTS: After adjustment for age, persons with mild cognitive impairment or mild AD had significantly poorer performance on parametric clinical tests of equilibrium and limb coordination compared with cognitively intact individuals (P < .05). CONCLUSIONS: Changes in equilibrium and limb coordination are clinically demonstrable in persons with mild cognitive impairment and mild AD using simple parametric tests. Such tests could potentially identify individuals with increased risk of falling. Early diagnosis and treatment of conditions that can jeopardize equilibrium and limb coordination, as well as balance and coordination training, might help cognitively impaired older people to maintain optimal function and may decrease the risk of falls and injuries.

Towards a science of Alzheimer's disease management: a model based upon current knowledge of retrogenesis.

BACKGROUND: General relationships between dotage and infancy and childhood have been acknowledged for more than two millennia. Recent findings indicate precise relationships between functional, praxic, and feeding changes in the course of the degenerative dementia of Alzheimer's disease (AD) and inverse corresponding developmental sequences. Similar inverse relationships between AD and human development can be described for cognition and language skills; for physiologic measures of electroencephalographic activity, brain glucose metabolism, and developmental neurologic reflex changes; and for the neuropathologic and neuroanatomic progression of these processes. In AD, these processes may be termed "retrogenesis." The relevance of the retrogenesis model for AD management is explored. METHOD: The functional stages of AD can be translated into developmental age equivalents that can be utilized to explicate observed changes in the disease. RESULTS: The retrogenesis-based developmental age model can usefully inform an understanding of the general care needs, emotional and behavioral changes, and activity needs of the AD patient. This model must be amended by necessary caveats regarding physical differences, variations in age-associated pathology, differences in social and societal reactions, and differences in background between AD patients and their developmental age "peers." CONCLUSIONS: Knowledge of retrogenesis and the developmental age of the AD patient can form a nidus for the development of a nascent science of disease management. Such a science must ultimately incorporate not only appropriate caveats but also relevant universal human needs, such as those for dignity, love, and movement.

Retrogenesis: clinical, physiologic, and pathologic mechanisms in brain aging, Alzheimer's and other dementing processes.

Data from clinical, electrophysiologic, neurophysiologic, neuroimaging and neuropathologic sources indicates that the progression of brain aging and Alzheimer's disease (AD) deterioration proceeds inversely to human ontogenic acquisition patterns. A word for this process of degenerative developmental recapitulation, "retrogenesis", has been proposed. These retrogenic processes provide new insights into the pathologic mechanism of AD deterioration. An understanding of retrogenic phenonmena can also result in insights into the applicability of retrogenic pathologic mechanisms for non-AD dementing disorders. Management strategies based upon retrogenesis have recently been proposed. Retrogenic pathophysiology also points to previously unexplored pharmacologic approaches to dementia prevention and treatment.

Progression of Alzheimer's disease: variability and consistency: ontogenic models, their applicability and relevance.

Much has been learned about the clinical symptomatology of Alzheimer's disease (AD) and ontogenic reciprocal relationships in the past few decades. It is now possible to describe and verify inexorable symptomatic sequences and corresponding temporal relationships. It is also possible to identify more variable symptoms in AD. Ontogenic models can be useful in providing a clearer understanding of the nature of AD symptomatology in terms of both consistency and variability. These models can also be informative in explicating the management needs of AD patients and the treatment possibilities of AD symptoms as well as the etiology of variability in AD symptoms.

Neuromotor changes in Alzheimer's disease: implications for patient care.

As a result of the neuropathologic process of Alzheimer's disease (AD), significant changes occur in neuromotor function (e.g., paratonia and compulsive grasping). These changes become manifest in the moderately severe stage of AD, when patients begin to require ongoing assistance with activities of daily life (ADL), and they are prominent in the severe stage of AD, when patients are continuously dependent on a caregiver. Patients in these stages often display behavioral disturbances during care activities. These disturbing behaviors result not only from cognitive impairment, but also from a patient's physical inability to cooperate with the caregiver. When care management strategies take into account the characteristic physical restrictions resulting from the neuromotor changes that accompany advanced AD, the caregiving process may be significantly facilitated.

Utility of developmental reflexes in the differential diagnosis and prognosis of incontinence in Alzheimer's disease.

Four developmental reflexes, the tactile suck reflex, the palmar and plantar grasp reflexes, and the plantar extensor reflex, were examined in 784 individuals, including healthy elderly, cognitively and functionally mildly impaired individuals, and patients with Alzheimer's disease (AD) in all stages of clinical severity. The study population was classified into six categories of increasingly impaired functional performance, and prevalence of the four individual reflexes and of a summary reflex measure, consisting of a combination of these four reflexes, was determined for each category. Prevalence of all five reflex measures was more than six times higher for those categories that comprised only permanently doubly incontinent patients as compared to those categories that comprised only continent individuals (P < .001). Frequency of developmental reflexes rose sharply with the onset of progressive incontinence. Since the return of these reflexes in AD is associated with severe cortical dysfunction, it is concluded that these developmental reflexes are useful in differentiating incontinence of cortical origin from incontinence resulting from potentially reversible causes.

Overview of methodologic issues for pharmacologic trials in mild, moderate, and severe Alzheimer's disease.

To address the issue of mild, moderate, and severe Alzheimer's disease (AD), it is necessary to initially establish some agreement on terminology. In recent decades, these terms have frequently been defined using screening instrument scores with measures such as the Mini-Mental State Examination (MMSE). There are many problems with this approach, perhaps the most salient of which is that it has contributed to the total and tragic neglect of patients with severe AD. An alternative approach to the classification of AD severity is staging. This approach has advanced to the point where moderately severe and severe AD can be described in detail. Procedures for describing this previously neglected latter portion of AD have recently been extensively validated. Staging is also uniquely useful at the other end of the severity spectrum, in differentiating early aging brain/behavior changes, incipient AD, and mild AD. Temporally, with staging procedures, it is possible to track the course of AD approximately three times more accurately than with the MMSE. The net result of the advances in AD delineation is that issues such as prophylaxis, modification of course, treatment of behavioral disturbances, loss of ambulation, progressive rigidity, and the development of contractures in AD patients can now be addressed in a scientifically meaningful way that will hopefully bestow much benefit in AD patients and those who care for them.

Contractures and loss of function in patients with Alzheimer's disease.

OBJECTIVE: To investigate the prevalence of contractures in patients with Alzheimer's disease and to assess possible associations between contractures and cognitive and functional decline in Alzheimer's disease. DESIGN: Case series. SETTING: Subjects from an outpatient, university-based, dementia research center, followed, when necessary, into residential home and nursing home settings. PATIENTS: A consecutive sample of 161 patients (48 men, 113 women; mean age 75.3 +/- 8.6 years) with a clinical diagnosis of probable Alzheimer's disease and with deficits in basic activities of daily living or more severe functional impairment. MAIN OUTCOME MEASURES: For cognition, the Mini-Mental State Examination (MMSE); for functioning, the Functional Assessment Staging Scale (FAST); contracture is defined as a decrease of 50% or more of the normal passive range of motion of the joint. RESULTS: Prevalence of contractures was correlated highly with degree of functional impairment (r = .70, P < .001). More than three quarters of patients who had lost the ability to walk manifested contractures; however, contractures were found in fewer than 11% of all ambulatory patients examined. When present, contractures involved more than one extremity in 97% of cases and involved all four extremities in more than two-thirds of patients. CONCLUSION: Joint contractures are very common in the severe stages of Alzheimer's disease. More than a quarter of a million institutionalized residents in US nursing homes are likely to be afflicted by this potentially painful and disfiguring condition. Possible pathophysiology and contributing factors and possible means of intervention for this major source of disability are discussed.