Search PubMed⌕ Search

Biomedical subjects

A N Exton-Smith

Publications and source records attributed to A N Exton-Smith.

At least 19 recordsLinked to original sources

Double-blind, placebo controlled study of acetyl-l-carnitine in patients with Alzheimer's dementia.

A randomized, double-blind, placebo-controlled, parallel-group clinical trial was carried out to compare 24-week periods of treatment with 1 g acetyl-l-carnitine twice daily and placebo in the treatment of patients with dementia of the Alzheimer type. A total of 36 patients entered the trial, of whom 20 patients (7 active, 13 placebo) completed the full 24 weeks. Whilst several of the efficacy indices showed little change in either group during the trial, there was an apparent trend for more improvement in the acetyl-l-carnitine group in relation to the Names Learning Test and a computerized Digit Recall Test, both related to aspects of short-term memory. Similarly, there was a trend for reaction time in the computerized classification test to show less deterioration in the active treatment group. Changes within groups, and changes between groups, failed to reach statistical significance, at least partially because of the small number of patients available for analysis. Two indices of overall therapeutic benefit showed a trend for less deterioration in the active-treatment group than in the placebo group. Nausea and/or vomiting occurred in 5 patients in the acetyl-l-carnitine group. Laboratory tests revealed no signs of drug toxicity. The results suggest that acetyl-l-carnitine may have a beneficial effect on some clinical features of Alzheimer-type dementia, particularly those related to short-term memory.

Acetylcarnitine↗

Relationship between the P300 auditory event-related potential and automated psychometric tests.

Event-related potentials particularly the P3 component have been noted to be abnormal in illnesses affecting cognitive processes, such as dementia. The relationship between the P3 latency and objective tests of mental function in patients with Alzheimer's disease and vascular dementia has been studied. A significant correlation was demonstrated between P3 latency and automated psychometric tests in patients with Alzheimer's disease.

Aged↗

The Memory Clinic. A new approach to the detection of dementia.

Memory impairment is a salient and early feature of developing dementia, but in practice is often not recognised until it has reached an advanced stage. The operation described is of a Memory Clinic opened on an experimental basis at the Geriatric Research Unit, University College London, in 1983, with the aim of identifying the causes of memory impairment in the elderly, with particular reference to the early detection of dementia. It proved possible to identify a group of people with early dementia who had previously been undiagnosed, and also to reveal deficiencies in the utilisation of existing services. Memory clinics would be a valuable addition to geriatric and psychogeriatric services.

Aged↗

Effects of age on body temperature and blood pressure in cold environments.

Mean deep body temperature fell by 0.4 +/- 0.1 (SD) degrees C in five sedentary, clothed 63-70 year old men and by 0.1 +/- 0.1 degrees C in four young adults after 2 h exposure in still air at 6 degrees C (P less than 0.001). The mean increase in systolic and diastolic pressure was significantly greater (P less than 0.002) in the older subjects (24 +/- 4 mmHg systolic, 13 +/- 4 mmHg diastolic) than in the young (14 +/- 6 mmHg systolic, 7 +/- 3 mmHg diastolic) after 2 h at 6 degrees C. A small rise in blood pressure occurred in the older men at 12 degrees C, but there was no increase in either group at 15 degrees C. The association of variables is particularly marked between systolic blood pressure and core temperature changes at 6 degrees C. There were no appreciable cold-adaptive changes in blood pressure or thermoregulatory responses after 7-10 days repeated exposure to 6 degrees C for 4 h each day. Blood pressure elevation in the cold was slower but more marked in the older men. These changes in blood pressure may provide a possible basis for delineating low domestic limiting temperature conditions.

Adolescent↗

The short-term effects of reducing elevated blood pressure in elderly patients with propranolol and dyazide.

Propranolol and Dyazide (25 mg hydrochlorothiazide and 50 mg triamterene) were used singly to reduce the elevated blood pressure (systolic ranging from 170 to 271 mmHg and diastolic ranging from 100 to 141 mmHg) of 38 elderly hypertensive patients whose ages ranged from 69 to 91 years. Each compound was administered for a period of four weeks with a wash-out period of four weeks in between. The following parameters were assessed before and after each treatment period: cerebral blood flow (CBF), mental functions, cardiac output (CO), electrocardiogram, glomerular filtration rate (GFR) and serum biochemistry. Both systolic and diastolic blood pressure were significantly reduced following the administration of either compound. No significant change in CBF and CO could be observed after reducing the blood pressure whether Propranolol or Dyazide was used. The GFR was, however, significantly reduced and the plasma creatinine significantly increased following Dyazide but not Propranolol administration. As expected the administration of the latter compound was associated with a significant bradycardia. No significant change could be observed in the other parameters studied.

Aged↗

Vitamin D status of the elderly in relation to age and exposure to sunlight.

Vitamin D status was assessed in 929 men and women aged 65 years and over during a nutrition survey lasting 56 weeks. Concentrations of 25-hydroxyvitamin D (25-OHD) measured in plasma samples showed a seasonal variation, being significantly higher in summer than in winter, and correlated with exposure to sunlight as measured by a 'sunshine score'. Regression analysis showed that 25-OHD concentrations fell with advancing age in both men and women and in summer and winter and approached the same value (about 10 ng/ml) at about the age of 95. This fall has implications in the occurrence of osteomalacia among the elderly and the increasing incidence with age of fractures of the femoral neck.

Activities of Daily Living↗

1983 Henderson Award Lecture. Thermal homeostasis in old age.

The relationships of homeostasis to the physiologic and socioeconomic concomitants of aging are presented. Neurohumoral control of body temperature may become deranged in old age as a result of changes in the intrinsic regulatory system. Drugs and stressful climatic temperatures can have deleterious effects. Sensitivity of the elderly to environmental temperature changes is diminished, and their resources to control environmental temperatures are likely to be limited, leaving them more vulnerable than the young to hypothermia and hyperthermia.

Aged↗

Immunological parameters in the aged and in Alzheimer's disease.

Peripheral blood from patients with Alzheimer's disease, elderly normal subjects and young (normal subjects) was examined with respect to leucocyte phenotypes and proliferative responses to lectins. Whole blood cell analysis showed that the neutrophil count was similar in all three groups. However, the lymphocyte count was depressed in the Alzheimer group. The monocyte count was reduced in the healthy aged and further reduced in the Alzheimer group. Analysis of peripheral blood mononuclear cells showed no change in the proportion of E+ cells, total T determined with the monoclonal antibody UCHT1 (similar to OKT3) and the T cell subsets: active E and T dot (discrete esterase staining). However, the proportion of T cells bearing the antigen detected by UCHT3 monoclonal antibody (similar to Leu 1 and OKT1) was reduced in the healthy aged and further reduced in the Alzheimer group. Proliferative responses to PHA, Con A, PA, and PWM were similarly depressed in both the aged and Alzheimer groups.

Adult↗

The elderly patient and multiple disease.

Effective management of the elderly depends on recognition of the distinction between disability and diseases which cause it and the assessment of the disability, both physical and mental, on a functional basis. The decline in physiological and mental performance and impaired homeostasis with age are discussed. The main factors which favour the development of multiple diseases in the elderly are summarized and the implications for treatment considered. The importance of early detection of disease and adequate treatment is stressed, but this is often made difficult due to the fact that many of the disabilities of the elderly living at home go unreported to the general practitioner.

Aged↗