Search PubMed⌕ Search

Biomedical subjects

J E Gallacher

Publications and source records attributed to J E Gallacher.

At least 19 recordsLinked to original sources
PubMed2001

Cognitive function and blood rheology: results from the Caerphilly cohort of older men.

OBJECTIVES: Vascular lesions are important contributors to cerebral disease, yet relatively little work has been done on relationships between haematological factors and cognitive function. We have explored these relationships in the Caerphilly cohort of older men. DESIGN: The development of vascular disease and the decline in cognitive function are being studied in a cohort of older men in Caerphilly, South Wales, UK. We have recorded a range of life-style, dietary, lipid, haematological and rheological factors which are, or may be, predictive of vascular disease. We have examined the relationships between these and both incident myocardial infarction and stroke, and identified factors relevant to cognitive function. SETTING: A community-based study based upon a representative population sample of older men. We collected data for the study from around 90% of the survivors of the original cohort. SUBJECTS: 2154 men who were aged 55-69 years at the time blood was taken for the haematological tests and cognitive function was tested. MAIN OUTCOME MEASURES: We present data from the AH4 test of general cognitive performance and from choice reaction time, a test of vigilance. RESULTS: There is a U-shaped relationship between haematocrit and cognitive function, the best cognitive function scores occurring at a mean haematocrit of 0.46. The relationship is significant for the choice reaction time (P < 0.05). The relationship between haematocrit and the AH4 test score is also curvilinear, but it is not significant. Plasma viscosity showed strong and robust relationships, with significantly better cognitive performance and faster reaction times at lower levels of viscosity (both relationships P < 0.001). Plasma fibrinogen concentration did not show any significant relationships with cognitive function. All these relationships are present, but are much weaker, with rheological tests that had been carried out 5 years before the cognitive testing. CONCLUSIONS: Blood rheology, as estimated by both haematocrit and plasma viscosity, is a significant determinant of cognitive function in older men. On the other hand, the thrombotic potential of blood, as indicated by fibrinogen level, shows no significant relationships. The relationships with rheology seem to be direct, presumably through blood flow at the time of testing, rather than through underlying long-term disease processes.

Aged↗
PubMed1999

Cognitive function in the Caerphilly study: associations with age social class, education and mood.

Baseline cognitive function was established for a study of pre-symptomatic cognitive decline in 1870 men from the general population aged 55-69 years as part of the third examination of the Caerphilly Study. Cognitive assessment included the AH4, a four choice serial reaction time task, a modified CAMCOG, MMSE, NART and various memory tests. Distributions and relationships with age, social class, education and mood at time of testing are presented for a younger population than has previously been available. Multiple linear regression showed cognitive function to be independently associated with all four factors. The age effect was equivalent to one half of a standard deviation (SD) in CRT and AH4 scores. Only the NART score was not associated with age, supporting the use of NART score as an estimate of pre-morbid IQ. The largest age adjusted differences between men with low and normal mood were for the AH4 (3 points, t = 5.6, p < 0.0001) and the CAMCOG (2 points, t = 5.8, p < 0.0001). The smallest age adjusted effect of mood was for the CRT (33 ms, t = 2.14, p = 0.32) and the MMSE (0.4 points, t = 2.97, p = 0.003). Age, mood and education adjusted social class effects were very large ranging between around 0.5 SD for the CRT, and 1.0 SD for the AH4 and NART, respectively. For educational status age, mood and social class adjusted differences were also substantial with tests for trend showing the largest differences for the NART (t = 12, p < 0.0001) and modified CAMCOG (t = 10.6, p < 0.0001) with the smallest differences for the CRT (t = 2.73, p = 0.006).

Affect↗
PubMed1999

Smoking, drinking, and other life style factors and cognitive function in men in the Caerphilly cohort.

STUDY OBJECTIVES: To examine the cognitive function in a large, ongoing cohort study of older men, and to identify associations with social and lifestyle factors. DESIGN: A cross sectional study of cognitive function was conducted within the Caerphilly Prospective Study of Heart Disease and stroke. SETTING: The Caerphilly Study was originally set up in 1979-83 when the men were 45-59 years of age. Extensive data are available on a wide range of lifestyle and other factors of possible relevance to cognitive decline. Associations between some of these and cognitive function are reported. PARTICIPANTS: A representative sample of 1870 men aged 55-69 years. MAIN RESULTS: Age, social class, medication, and mood were found to be powerful determinants of performance. Self report data on the involvement of the men in leisure pursuits were examined by factor analysis. This indicated that the more intellectual leisure pursuits are the most strongly linked with performance. A measure of social contact showed a weak positive association with the test scores. Current cigarette smokers gave lower test cognitive function scores than either men who had never smoked, or ex-smokers. There was however no evidence of any gradient in function with the total lifetime consumption of tobacco. The disparity between these two data sets suggests that there had been prior selection of men who had originally started to smoke, but more particularly selection of those who later quit smoking. There was no significant association between alcohol consumption and cognitive function, though ex-drinkers had markedly lower test scores than either current drinkers or men who had never drunk alcohol. This seemed probably to be a consequence of an high prevalence of illness among the ex-drinkers. CONCLUSIONS: Age and social class show strong associations with cognitive function. Leisure persuits and social contact are also both positively associated. Neither tobacco smoking nor the drinking of alcohol seem to be associated with cognitive function, though there is evidence suggestive of self selection of both men who had never smoked and ex-smokers.

Age Factors↗
PubMed1996

Blood pressure reactions to the cold pressor test and the prediction of future blood pressure status: data from the Caerphilly study.

The prognostic significance of the cold pressor test in hypertension remains a matter of controversy. Following determination at an initial screening session, blood pressure (BP) was recorded at baseline rest and in reaction to a cold pressor test. Follow-up screening BP was determined 5 years later. The effective sample was 1039 men, with an average age of 56.6 years at initial screening. Step-wise multiple regression indicated that BP reactions to the cold pressor test provided minimal independent prediction of follow-up BP over and above that afforded by BP at initial screening. In the case of follow-up systolic pressure, a model including only age and initial screening systolic BP (SBP) accounted for 38% of the variance; SBP reactions to the cold pressor did not enter the regression equation. In the case of follow-up diastolic BP (DBP), diastolic pressure at initial screening accounted for 21% of the variance, and while DBP reaction to the cold pressor test entered the equation, it accounted for only an additional 1% of the variance. These results suggest that the cold pressor test may be of limited clinical use in older populations.

Blood Pressure↗
PubMed1995

Attitudes and ischaemic heart disease in the Caerphilly Study: the Health Attitude Inventory.

BACKGROUND: The Health Attitude Inventory (HAI) is developed to assess attitudes, beliefs and values towards coronary-related behaviour in epidemiological studies. It comprises a 76-item self-administered questionnaire which can be completed in under 10 minutes by most adults. METHODS: The HAI was administered to 2100 men aged 50-64 years along with measures of ischaemic heart disease risk factors, including the following coronary-related behaviours: smoking, exercise, type A behaviour and the consumption of fried food, dairy produce, wholemeal bread and vegetables. RESULTS: Cross-sectional analyses using linear regression showed attitudes, beliefs and values to explain between 8% and 27% of the variance in the dietary coronary-related behaviour. For exercise 13% of the variance was explained, and for type A behaviour 18%. Similar analysis for smoking using logistic regression (non-smoker versus current smoker) showed a predictive concordance of 95%. CONCLUSIONS: The HAI has demonstrated the assessment of attitudes, beliefs and values in an epidemiological setting to show associations with a range of coronary risk behaviours. This finding has potential public health as well as aetiological application in that influential attitudes, values and beliefs can be identified to aid increasing healthy as well as reducing risky coronary-related behaviour.

Attitude to Health↗
PubMed1992

A population survey of ischaemic heart disease and minor psychiatric disorder in men.

Associations between ischaemic heart disease and psychiatric morbidity in hospital recruited samples may be confounded by differential referral of patients with co-morbidity. Associations of angina, past history of myocardial infarction, blood pressure, and electrocardiographic evidence of ischaemia with psychiatric disorder can best be examined in community samples as reported here in 2204 middle-aged men from the Caerphilly Collaborative Study. There was a strong association between past history of myocardial infarction, non-specific chest pain, Angina Grade II and psychiatric disorder measured by the 30-item General Health Questionnaire. Electrocardiographic evidence of ischaemia alone was not significantly associated with psychiatric disorder. It is suggested that non-specific chest pain is a symptom of psychiatric disorder; conversely in severe angina psychiatric disorder is secondary to the pain, restricted activity and threat to life which angina implies.

Chest Pain↗
PubMed1991

Social factors and minor psychiatric disorder in middle-aged men: a validation study and a population survey.

A cross-sectional survey of minor psychiatric disorder is reported in a representative community sample of 2204 men between the ages of 45 years and 64 years living in Caerphilly, South Wales. Minor psychiatric disorder was measured by the 30-item General Health Questionnaire and validated by the Clinical Interview Schedule in a consecutive sample of 97 men, weighted to provide one-third cases, two-thirds non-cases. A case threshold of 4/5 on the General Health Questionnaire was chosen on the basis of 'ROC' analysis. An overall estimated 'true' prevalence rate for minor psychiatric disorder of 22.0% was found, with 22.3% of men scoring 5 or more on the General Health Questionnaire. Rates of minor psychiatric disorder were higher in widowed and divorced men than in married men but were also, unexpectedly, lower in single as opposed to married men. There was no social-class gradient in minor psychiatric morbidity but a lower rate in Social Class III NM may be largely explained by lower unemployment rates. There were markedly higher rates of minor psychiatric morbidity in unemployed men and those who retired ill. Men with no available social contacts had higher rates of morbidity than men with some or high social contacts.

Cross-Sectional Studies↗
PubMed1989

Blood viscosity and hearing levels in the Caerphilly Collaborative Heart Disease Study.

Data from 342 men who are participants in the Caerphilly Collaborative Heart Disease Study were used to replicate a previous report of a significant relationship between measures of whole-blood viscosity and hearing levels in persons with sensorineural hearing impairment. In the unselected data, there were significant relationships between measures of whole-blood viscosity at high shear rates and hearing threshold levels at 2000 and 4000 Hz, even after accounting for the effects of age and socioeconomic group. In a subset of the data containing 124 persons selected on the basis of likely sensorineural hearing impairment, there were significant relationships between whole-blood viscosity and hearing level at all frequencies, with stronger effects at the higher frequencies. The data support the contention of a potentially important relationship between whole-blood viscosity and sensorineural hearing impairment.

Audiometry, Pure-Tone↗
PubMed1989

A framework for the adaptation of psychological questionnaires for epidemiological use: an example of the Bortner Type A scale.

A model for the systematic adaptation of psychological questionnaires for epidemiological use is presented. Application of the model is illustrated using variants of the Bortner Type A scale in a representative age/sex stratified sample of 256 persons. Through the application of the model the Bortner scale was adapted to compare the effects of scale direction, scale format and example position. Overall the Bortner scale was shown to provide robust measurement which was little affected by response rate, age, sex or by the adaptations of the scale. An association was found of sex with response rate. Interaction effects of sex and scale direction on mean Type A scores, and of example position and scale format on both response rate and Type A score variability were also found. In identifying critical aspects of questionnaire performance, and in providing a coherent framework for their interrelationship, the model acts as a guide to the systematic assessment of questionnaire performance. The use of this model will, therefore, facilitate greater confidence in the interpretation of questionnaire data in epidemiological studies.

Adult↗
PubMed1989

Coffee, blood pressure and plasma lipids: a randomized controlled trial.

A randomized controlled trial was conducted to examine the effects of coffee (as commonly drunk in Britain) on blood pressure and plasma lipids in healthy subjects. Fifty-four subjects followed three regimens successively, the order being randomized according to a Latin square design: five or more cups of coffee daily for 4 weeks; five or more cups of decaffeinated coffee daily for 4 weeks but no ordinary coffee; no coffee for 4 weeks. Coffee appeared to cause a small rise (of 3 mm Hg) in recumbent systolic blood pressure; this effect was less than, and obscured by, changes induced by posture and mild stress. No consistent changes attributable to coffee were found in diastolic blood pressure or pulse rate. Small changes in the expected directions occurred in plasma high density lipoprotein (HDL) cholesterol and apolipoprotein AI (decrease), and in total cholesterol, non-HDL cholesterol and apolipoprotein B (increase), but none of these were statistically significant. The effect of coffee on risk of heart disease in Britain is probably small.

Adolescent↗
PubMed1988

Type A behaviour and pressor response in a representative sample of middle-aged men.

The hypothesis that type A behaviour is associated with greater pressor response to stress was tested in a representative sample of 114 men aged 30-65 yr. Jenkins Activity Survey, Framingham and Bortner type A scores were related to blood pressure and heart rate under rest, serial reaction time, mental arithmetic, and noise conditions. Type A scores were modestly intercorrelated (r = 0.59 to r = 0.67). Type A scores were inversely related to age and resting systolic pressure and were independent of smoking history, social class, marital status, and task performance parameters. Type A scores were not related to pressor or heart rate response to stress under any of the stress conditions. These findings do not support the importance of physiological response as an explanation of the association between type A and heart disease.

Adult↗
PubMed1988

Type A behaviour, eating pattern and nutrient intake: the Caerphilly Study.

Relationships between type A behaviour and eating pattern and nutrient intake were investigated in a representative sample of 532 employed men aged 45-59 years drawn from the Caerphilly study. Eating pattern and nutrient intake were assessed by 7-day weighed dietary records. A change in Framingham type A scores from the lower third to the upper third was associated with a 9% reduction in meal size and a 6% increase in meal frequency. No trends with type A were found for nutrient intake in absolute terms. For means of nutrient intake as a percentage of energy, however, higher values for sugar and lower values for starch and polyunsaturated fat were observed with higher type A scores. In multiple regression analysis, after control for the effects of age, height, social class and smoking, significant associations with type A were found only for meal size, dietary fibre per MJ and sugar as a percentage of energy. It is concluded that diet is unlikely to be an explanation of the relationship between type A and ischaemic heart disease.

Diet↗
PubMed1988

Type A behaviour and prevalent heart disease in the Caerphilly study: increase in risk or symptom reporting?

Type A behaviour was assessed by modified Framingham scale in a total sample of 1956 employed men in the Caerphilly study. Prevalent heart disease was measured by cardiovascular questionnaire to obtain evidence of myocardial infarction and angina, and by electrocardiogram (ECG) for evidence of ischaemia. Type A was inversely related to age and systolic blood pressure and was positively related to social class and height. It was not related to serum cholesterol or alcohol consumption. After control for age, systolic blood pressure, height, smoking and social class, type A was found to be independent of angina but positively associated with an increased risk of possible myocardial infarction (MI). Type A was also associated with increased risk of confirmed MI. An inverse association was found between type A and asymptomatic ischaemic heart disease (IHD). The association between type A and symptomatic IHD could be due to symptom reporting.

Age Factors↗
PubMed1985

Automatic measurement of blood pressure: evaluation of the Copal UA-231 automatic sphygmomanometer.

The suitability of an automatic sphygmomanometer for epidemiological work was evaluated in two studies. In the first, blood pressure measurements were made alternately on the automatic machine and on a Hawksley random zero instrument on 14 volunteers on each of four consecutive days by a single medical observer. No significant difference was found between the mean diastolic pressure obtained by each instrument but the mean systolic pressure was 5 mm higher on average on the automatic machine. In the second study, the effect of cuff position for the automatic instrument was examined. Differences between recommended and errant cuff positions of up to 4.5 mmHg were recorded but these did not reach statistical significance. These studies indicate that if used carefully this automatic instrument is suitable for survey and experimental use.

Adult↗