PubMed Health⌕ Search

Biomedical subjects

N Sharpe

Publications and source records attributed to N Sharpe.

At least 73 records · Page 4Linked to original sources
PubMed1996

Role of patients' view of their illness in predicting return to work and functioning after myocardial infarction: longitudinal study.

OBJECTIVE: To examine whether patients' initial perceptions of their myocardial infarction predict subsequent attendance at a cardiac rehabilitation course, return to work, disability, and sexual dysfunction. DESIGN: Patients' perceptions of their illness were measured at admission with their first myocardial infarction and at follow up three and six months later. SETTING: Two large teaching hospitals in Auckland, New Zealand. SUBJECTS: 143 consecutive patients aged under 65 with their first myocardial infarction. MAIN OUTCOME MEASURES: Attendance at rehabilitation course; time before returning to work; measures of disability with sickness impact profile questionnaire for sleep and rest, social interaction, recreational activity, and home management; and sexual dysfunction. RESULTS: Attendance at the rehabilitation course was significantly related to a stronger belief during admission that the illness could be cured or controlled (t = 2.08, P = 0.04). Return to work within six weeks was significantly predicted by the perception that the illness would last a short time (t = 2.52, P = 0.01) and have less grave consequences for the patient (t = 2.87, P = 0.005). Patients' belief that their heart disease would have serious consequences was significantly related to later disability in work around the house, recreational activities, and social interaction. A strong illness identity was significantly related to greater sexual dysfunction at both three and six months. CONCLUSIONS: Patients' initial perceptions of illness are important determinants of different aspects of recovery after myocardial infarction. Specific illness perceptions need to be identified at an early stage as a basis for optimising outcomes from rehabilitation programmes.

Activities of Daily Living↗
PubMed1996

Beta-blockers in heart failure. Future directions.

The rationale for beta-blockade in heart failure is now well established. Heart failure mortality, which is predicted by neurohormonal activation, remains high despite modern treatment including ACE inhibition, and additional neurohormonal blockade has further therapeutic potential. Previous clinical trial experience in heart failure, most of which has been in patients with idiopathic cardiomyopathy, indicates consistent improvement in ventricular function although variable changes in symptoms and exercise performance. However, the major burden of heart failure occurs in patients with ischaemic heart disease and in this respect it is notable that beta-blockade following myocardial infarction confers significant mortality benefit in subgroups with heart failure. The Australia and New Zealand carvedilol heart failure study is the largest completed study of beta-blocker treatment in patients with heart failure of ischaemic aetiology, including 415 patients randomized to carvedilol or placebo and indicating excellent tolerability of a titrated dose regimen and improved ventricular function after 6 months of treatment. An overview of all currently available randomized clinical trials of beta-blockade in heart failure, which includes more than 1600 patients, indicates a mortality risk reduction of approximately 20% but with wide confidence intervals. A large scale trial with several thousand patients is required to detect reliably a plausible 15-20% mortality reduction with beta-blockade in heart failure. The dissociation of clinical and mortality effects demonstrated with other heart failure treatments indicates the necessity for an appropriately powered mortality study which could define a major improvement in heart failure therapy for the future.

Adrenergic beta-Antagonists↗
PubMed1996

Optimal treatment of angina in older patients.

Ischaemic heart disease is a major problem in the elderly. Compared with younger patients, coexisting medical conditions are more common and the patients are more likely to be receiving multiple drugs. In addition, drug pharmacodynamics are altered in the elderly and this needs to be carefully considered when commencing treatment for angina. In practice, the general principles of management of elderly patients with angina are similar to that of younger patients. However, particular care needs to be taken with the therapeutic regimens used. This article reviews the approach to the treatment of stable exertional angina in the elderly.

Adrenergic beta-Antagonists↗
PubMed1996

Medical management after myocardial infarction: an evidence-based perspective.

There are a number of effective therapies to consider for the patient after myocardial infarction (MI). Careful patient assessment and individualisation of treatment is required for maximum benefit. Key aspects of assessment include consideration of continuing myocardial ischaemia, evaluation of LV function, review of risk factors and patient circumstances relevant to rehabilitation. Thrombolysis for eligible patients and acute aspirin are of proven benefit and the priority is to minimise delay in treatment. Aspirin is indicated long term for all patients. Beta-blockers, ACE inhibitors and possibly nitrates are also beneficial, but questions remain about optimal timing and combination treatment. Anticoagulants should be considered in selected, high-risk patients. Education-counselling measures should be initiated in hospital and continued with risk-factor modification as part of rehabilitation after discharge. Priority should be given to smoking cessation where applicable, and to reduction of elevated serum cholesterol levels.

Adrenergic beta-Antagonists↗
PubMed1995

Hospital admissions and deaths due to congestive heart failure in New Zealand, 1988-91.

AIMS: Congestive heart failure is believed to be a major public health problem in most Western countries; however, little is known about the extent of morbidity and mortality from congestive heart failure in New Zealand. This paper reports data on hospital admissions and mortality due to congestive heart failure in New Zealand during the years 1988-91. METHODS: All data were obtained from the New Zealand Health Information Service. Deaths from congestive heart failure were identified from ICD-9 codes indicating a primary diagnosis of congestive heart failure. Hospitalisations for congestive heart failure were identified both from ICD-9 codes indicating a primary diagnosis of congestive heart failure and from codes indicating a diagnosis of congestive heart failure secondary to chronic rheumatic heart disease, ischaemic heart disease or valvular heart disease (nonrheumatic). RESULTS: Each year there was an average of about 850 deaths ascribed to heart failure; two-thirds of these occurred in patients over the age of 75 years. Each year there was also an average of about 8000 hospital admissions of about 5000 patients for congestive heart failure; 75% of these admissions involved patients over 65 years old. The mean duration of hospital stay for congestive heart failure was 16 days. On this basis, it is estimated that hospital admissions for congestive heart failure are likely to cost about NZ$50 million each year, or about 1% of the total health budget. CONCLUSIONS: Congestive heart failure is clearly a major public health problem in New Zealand with high hospitalisation and mortality rates. Several strategies have been proven to reduce mortality and hospital admissions for congestive heart failure and these should be utilised widely in patients at risk.

Aged↗
PubMed1995

Thrombolysis in acute myocardial infarction: reducing in hospital treatment delay.

AIM: Thrombolytic treatment when given early in acute myocardial infarction is beneficial. This study was initiated to firstly, document the existing time delays in the administration of thrombolysis at Auckland Hospital, and secondly, prospectively assess the effect of a staff education programme to reduce in-hospital delay. The goal was a "door to needle time" of less than 30 minutes. METHODS: The time delays in the administration of thrombolysis to patients with acute myocardial infarction admitted to the coronary care unit at Auckland Hospital were established. This was done with a retrospective chart review over a six month period January to June 1993. This was followed by a staff education programme to fast track the management of patients eligible for thrombolysis. A prospective assessment was performed from February to May 1994 to audit the effectiveness of the programme. RESULTS: Most of the delay in the administration of thrombolysis occurred in the community prior to arrival at hospital (median delay 2.5 hours). However there was still a significant delay in hospital with a median door to needle time of 59 minutes in 1993. Following the education programme in 1994 the median door to needle time was reduced by 32% to 40 minutes (p = 0.03). The proportion of patients with a door to needle time of less than 30 minutes doubled from 13% in 1993 to 27% in 1994 (p = 0.18). CONCLUSION: Staff training and thrombolysis guidelines are effective in reducing in-hospital treatment delay but additional strategies may be warranted. Thrombolysis should be administered in the coronary care unit or emergency department to avoid delay. Ongoing assessment of standards will be required in the general hospital setting as a quality indicator.

Adult↗
PubMed1995

Association of angiotensinogen gene T235 variant with increased risk of coronary heart disease.

Several genes, including some encoding components of the renin angiotensin system, are associated with the risk of cardiovascular diseases. There have been reports linking a homozygous deletion allele of the angiotensin converting enzyme (ACE) gene (DD) with an increased risk of myocardial infarction, and some variants of the angiotensinogen gene with an increased risk of hypertension. In a case-control study of a caucasian population from New Zealand, we examined the associations with coronary heart disease (CHD) of ACE DD and of a mis-sense mutation with methionine to threonine aminoacid substitution at codon 235 in the angiotensinogen gene (T235). We studied 422 patients (mean age 62 years, 81% male) with documented CHD (50% with myocardial infarction) and 406 controls without known CHD (frequency-matched to cases by age and sex). Risk factors for CHD were assessed by standard questionnaire, physical examination, and blood tests. Genomic DNA from leucocytes was analysed for various ACE and angiotensinogen alleles. Angiotensinogen T235 homozygotes were at significantly increased risk of CHD generally (odds ratio 1.7, 2 p = 0.008) and of myocardial infarction specifically (1.8, 2 p = 0.009). Adjustment for several risk factors increased the estimate of CHD risk associated with this allele to 2.6 (2 p < 0.001) and the estimate for myocardial infarction risk to 3.4 (2 p < 0.001). By contrast, there was no evidence of a significant increase in the risk of CHD or myocardial infarction among individuals with ACE DD. We conclude that the T235 polymorphism of the angiotensinogen gene is an independent risk factor, which carries an approximately two-fold increased risk of CHD. In this study, however, ACE DD was not associated with any detectable increase in CHD risk.

Alleles↗
PubMed1995

Comparison of echocardiographic variables between type I diabetics and normal controls.

This report compares echocardiographic estimates of systolic and diastolic function and ventricular dimensions in type I diabetics and normal controls. A random sample of 60 diabetics selected from a central hospital diabetic clinic was compared with a sample of 40 nondiabetic controls, and matched to the diabetics by age, gender, and blood pressure. Simple comparisons showed that diabetics had a higher mean resting heart rate (HR) (p < 0.001) and a slower diastolic early filling phase (maximal rate of increase in left ventricular dimension in early diastole [v/dtmax], p = 0.08; time from end-systole until dv/dtmax [ES-dv/dtmax], p = 0.03), which were explained by differences in HR and other factors. Resting HR was significantly associated with several echocardiographic variables, but the slope relating resting HR to ventricular dimension was more negative in diabetics than in controls (end-diastolic diameter, p < 0.008; end-systolic diameter, p < 0.005), and the ratio of systolic to diastolic duration was significantly (p < 0.01) less positive in diabetics. The association of resting HR to duration of isovolumic diastole was positive in diabetics and negative in controls (p < 0.02). Among diabetics, those with higher resting HR had more retinopathy (p < 0.05), microalbuminuria (p < 0.05), smaller ventricles (p < 0.01), and longer isovolumic diastole (p < 0.05). Poorer diabetic control was associated with poorer systolic (fractional shortening, p < 0.05) and diastolic (dv/dtmax, p < 0.05; ES-dv/dtmax, p < 0.05) function.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

Readability of subject information leaflets for medical research.

AIM: To compare the readability of adult subject information leaflets prepared for medical research projects with the readability scores of a range of New Zealand newspaper editorials and popular magazine articles. METHODS: Of the 134 research projects approved by the Auckland Area Health Board in 1991, 99 were analysed together with nine randomly selected newspaper editorials and nine randomly selected articles from popular magazines. The Flesch reading ease index, the Flesch-Kincaid index and the Gunning fog index were calculated using a computerised grammar checker. RESULTS: Subject information leaflets were easier to read than newspaper editorials but significantly more difficult to read than articles in popular magazines. The Flesch reading ease index showed that information leaflets had a median readability score of 53 compared with magazines which had a score of 67 and newspaper editorials which had a score of 48. The level of secondary school education required to read information leaflets was equivalent to about 2 years or form 4, whereas a level of about form 5 appears to be required to read newspaper editorials and a level of about form 1 for magazine articles. CONCLUSIONS: The readability level of information leaflets prepared for participants in medical research in the Auckland area appears satisfactory and the process for reviewing this component of the research protocol appears consistent and effective. Readability scores may be a useful tool in assessing the overall ease with which written information can be read.

Clinical Trials as Topic↗
PubMed1994

Beta-blockers in heart failure: promising or proved?

Despite recent improvements in the management of congestive heart failure, the prognosis of many patients with this condition remains poor. The level of neurohormonal activation appears to be predictive of survival, and clinical studies indicate that inhibition of overactivated neurohormonal systems may be beneficial. Activation of the renin-angiotensin-aldosterone system is well documented in heart failure, and angiotensin-converting enzyme inhibition now has an established role in treatment based on evidence of hemodynamic, symptomatic and mortality benefit. Sympathetic nervous system activation also occurs as a compensatory mechanism in heart failure but with long-term deleterious effects. Increasing evidence suggests that beta-adrenergic blockade can produce hemodynamic and symptomatic improvement in heart failure of idiopathic or ischemic etiology. Trials of beta-adrenergic blocking agents in patients after myocardial infarction suggest a beneficial effect on mortality, even among those with heart failure. However, there remains uncertainty as to how generalizable are the results from the postinfarction trials, particularly in the current therapeutic environment with routine angiotensin-converting enzyme inhibitor therapy. Appropriately powered randomized, controlled trials are required to determine precisely the balance of benefit and risk resulting from long-term beta-blocker therapy in patients with heart failure of ischemic and other etiology.

Adrenergic beta-Antagonists↗
PubMed1994

Doppler echocardiography and the early diagnosis of carditis in acute rheumatic fever.

BACKGROUND: The incidence of acute rheumatic fever in New Zealand remains relatively high. Reliable early diagnosis of carditis is difficult and important in management. AIM: To determine if Doppler echocardiography contributed to the early diagnosis of carditis in acute rheumatic fever. METHODS: Forty-seven patients admitted to hospital with suspected acute rheumatic fever and 19 control patients, with a febrile illness due to a documented non-cardiac bacterial infection, were assessed two days and two weeks following admission. Presence or absence of clinical carditis was determined by a cardiologist unaware of the suspected diagnosis, from clinical examination, chest radiograph, electrocardiogram (ECG) and two dimensional echocardiogram. Doppler echocardiography was then performed and interpreted by a second cardiologist unaware of the diagnosis. After completion of the study the Jones criteria were applied, to categorise the patients with suspected acute rheumatic fever into four groups for the final diagnosis: no acute rheumatic fever, possible acute rheumatic fever, definite acute rheumatic fever without carditis, and definite acute rheumatic fever with carditis. RESULTS: In 19 patients with a final diagnosis of acute rheumatic fever and carditis at the baseline assessment carditis was detected by clinical assessment in 15 patients, compared with 19 patients with evidence of significant valve regurgitation by Doppler echocardiography. Following the two week assessment, all 19 patients had both clinical and Doppler evidence of carditis. Five patients with a final clinical diagnosis of possible acute rheumatic fever or definite acute rheumatic fever without carditis, had a Doppler abnormality detected. There was no clinical or Doppler abnormality in the febrile controls. CONCLUSIONS: Doppler echocardiography is more sensitive than clinical assessment in the detection of carditis in acute rheumatic fever, and can contribute to earlier diagnosis.

Acute Disease↗
PubMed1994

Estimation of arterial stiffness, compliance, and distensibility from M-mode ultrasound measurements of the common carotid artery.

BACKGROUND AND PURPOSE: Arterial stiffness may indicate early vascular changes that predispose to the development of major vascular disease. The repeatability of a variety of indices of arterial stiffness calculated from a standard carotid arterial M-mode ultrasound image was investigated. METHODS: Twenty-six asymptomatic normal subjects were imaged and had blood pressure recordings on each of two separate occasions at least 1 day apart. Using a computer-assisted method, the maximum and minimum internal diameter and average wall thickness of the right common carotid artery were measured over several cardiac cycles, and the following indices of arterial stiffness and distensibility (compliance) were derived: the pressure-strain elastic modulus (Ep), Young's modulus (E), cross-sectional compliance (CC), and the distensibility coefficient (DC). RESULTS: The repeatability of these measures, expressed as coefficients of variation, was as follows: Ep, 18%; E, 24%; CC, 14%; and DC, 13%. In another group of 20 subjects, the coefficient of variation for repeat examination by different sonographers was Ep, 19%; E, 20%; CC, 14%; and DC, 17% and for the one sonographer using two ultrasound machines was Ep, 13%; E, 13%; CC, 11%; and DC, 13%. These values indicate a moderate level of repeatability. In a univariate analysis each of these indices was significantly related to increasing age (Ep = 1.0 + 12.9 x AGE, r = .80; E = 314.5 + 13.9 x AGE, r = .48; CC = 22.6-0.26 x AGE, r = -.63; DC = 64.0-0.65 x AGE, r = -.78) but not to wall thickness (all P > .47). Using multiple regression techniques to adjust for age, wall thickness is a significant predictor of distensibility (P = .017), cross-sectional compliance (P < .001), and the pressure-strain elastic modulus (P = .019). Because Young's modulus is calculated from wall thickness, it could not be included in the multivariate analysis. CONCLUSIONS: We conclude that estimates of carotid artery distensibility and cross-sectional compliance derived from M-mode ultrasound recordings are moderately repeatable and may provide useful additional end points for trials of atherosclerotic progression.

Adult↗
PubMed1994

Effect of fosinopril on cardiac and metabolic parameters in patients with NIDDM.

OBJECTIVE: To determine whether the angiotensin-converting enzyme (ACE) inhibitor fosinopril can favorably alter cardiac function in non-insulin-dependent diabetes mellitus NIDDM) patients who have either normal blood pressure (BP) or mild, untreated hypertension. RESEARCH DESIGN AND METHODS: Fifty-five NIDDM subjects with normal BP or mild, untreated hypertension were randomized to treatment with the ACE-inhibitor fosinopril or placebo for 6 months in a randomized, double-blind trial to determine the effect of fosinopril on echocardiographic measurements. RESULTS: Left ventricular mass index (LVMI) fell by 6.5 +/- 4.7% (mean +/- SD) with fosinopril and increased by 8.6 +/- 3.5% during placebo treatment (P < 0.02), and isovolumic relaxation time improved significantly in those with elevated baseline levels (P = 0.02). Systolic BP fell significantly, but this did not correlate with the change in LVMI, suggesting a possible direct action of fosinopril on the heart. CONCLUSIONS: Fosinopril appears to have significant cardiac benefits in patients with NIDDM who have normal or mildly elevated BP. These benefits are achieved without adversely affecting renal status and without impairing metabolic control of diabetes.

Blood Glucose↗
PubMed1994

The effect of exercise episode duration on blood pressure.

OBJECTIVE: To investigate the effect on blood pressure for 10-min compared with 40-min episodes of physical activity for 4 days. DESIGN AND METHODS: The design used a randomized crossover trial of two exercise episode durations, involving 17 subjects, which were performed in a university setting. The intervention was exercise on a stationary bicycle for four consecutive days, at 50% of maximal oxygen uptake (determined by heart rate), for episode durations of 10 or 40 min. A rest period of 10 days followed before exercise for the alternative duration was performed. The main outcome measure was blinded assessment of blood pressure 24 h after the last exercise episode. RESULTS: Significant reductions were found in systolic and diastolic blood pressure after 4 days of 40 min but not after 4 days of 10 min stationary cycling. The reduction in blood pressure was significant for both systolic and diastolic blood pressure for 4 days of 40 min of exercise episodes. CONCLUSION: Exercise of moderate intensity on a stationary bicycle for 10 min for 4 days is not effective in lowering blood pressure in comparison with the same exercise for 40 min for 4 days. The experimental design employed in the present study has potential for monitoring the effects of exercise on blood pressure.

Blood Pressure↗
PubMed1993

The cardiac form of the tissue-specific SmN protein is identical to the brain and embryonic forms of the protein.

The SmN protein is a component of small nuclear ribonucleoprotein particles and closely related to the ubiquitously expressed SmB and B' splicing proteins. However, SmN is only expressed in a limited range of tissues and cell types such as brain, heart and early embryonic cells. The isolation of cDNA clones derived from the mRNA encoding SmN in different cell types has indicated that the brain and embryonic forms of the protein are identical and are encoded by a distinct gene to that encoding SmB and B'. It has been suggested however, that the cardiac form of SmN is encoded by a distinct mRNA which is derived from a different gene from that encoding the brain and embryonic forms of SmN. By using the polymerase chain reaction as well as cDNA cloning we have shown that this is not the case and that the cardiac, brain and embryonic forms of the protein are identical and are translated from the same mRNA encoded by a single gene. The significance of this finding is discussed in terms of the complex expression pattern of this gene and the possible functional role of SmN.

Amino Acid Sequence↗
PubMed1993

ACE inhibitors versus diuretics: when to choose which drug?

ACE inhibitors and diuretics should be used in combination in the majority of patients with clinical congestive heart failure. The broad spectrum of heart failure should include the phase of significant left ventricular dysfunction without overt clinical heart failure for which ACE inhibitor treatment alone may be beneficial in selected cases.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1993

B-mode ultrasound images of the carotid artery wall: correlation of ultrasound with histological measurements.

B-mode ultrasound is being used to assess carotid atherosclerosis in epidemiological studies and clinical trials. Recently the interpretation of measurements made from ultrasound images has been questioned. This study examines the anatomical correlates of B-mode ultrasound of carotid arteries in vitro and in situ in cadavers. Twenty-seven segments of human carotid artery were collected at autopsy, pressure perfusion fixed in buffered 2.5% glutaraldehyde and 4% paraformaldehyde and imaged using an ATL UM-8 (10 MHz single crystal mechanical probe). Each artery was then frozen, sectioned and stained with van Gieson or elastin van Gieson. The thickness of the intima, media and adventitia were measured to an accuracy of 0.01 mm from histological sections using a calibrated eye graticule on a light microscope. Shrinkage artifact induced by histological preparation was determined to be 7.8%. Digitised ultrasound images of the artery wall were analysed off-line. The distance from the leading edge of the first interface (LE1) to the leading edge of the second interface (LE2) was measured using a dedicated programme. LE1-LE2 measurements were correlated against histological measurements corrected for shrinkage. Mean values for the far wall were: ultrasound LE1-LE2 (0.97 mm, S.D. 0.26), total wall thickness (1.05 mm, S.D. 0.37), adventitia (0.35 mm, S.D. 0.16), media (0.61 mm, S.D. 0.18), intima (0.09 mm, S.D. 0.13). Ultrasound measurements corresponded best with total wall thickness, rather than elastin or the intima-media complex. Excision of part of the intima plus media or removal of the adventitia resulted in a corresponding decrease in the LE1-LE2 distance of the B-mode image. Furthermore, increased wall thickness due to intimal atherosclerotic thickening correlated well with LE1-LE2 distance of the B-mode images. B-mode images obtained from the carotid arteries in situ in four cadavers also corresponded best with total wall thickness measured from histological sections and not with the thickness of the intima plus media. In conclusion, the LE1-LE2 distance measured on B-mode images of the carotid artery best represents total wall thickness of intima plus media plus adventitia and not intima plus media alone.

Adult↗