PubMed Health⌕ Search

Biomedical subjects

A G Barnett

Publications and source records attributed to A G Barnett.

7 recordsLinked to original sources
PubMed2004

Estimating trends and seasonality in coronary heart disease.

We present two methods of estimating the trend, seasonality and noise in time series of coronary heart disease events. In contrast to previous work we use a non-linear trend, allow multiple seasonal components, and carefully examine the residuals from the fitted model. We show the importance of estimating these three aspects of the observed data to aid insight of the underlying process, although our major focus is on the seasonal components. For one method we allow the seasonal effects to vary over time and show how this helps the understanding of the association between coronary heart disease and varying temperature patterns.

Adult↗
PubMed2001

The use of pre-conceptional folic acid as an indicator of uptake of a health message amongst white and Bangladeshi women in Tower Hamlets, east London.

BACKGROUND: The benefit of folic acid is a simple health promotion message of proven effectiveness that is particularly pertinent to a young population with a high birth rate. OBJECTIVE: The aim of the present study was to compare the uptake of a folic acid health message in two different ethnic groups. METHODS: Community antenatal teams in Tower Hamlets were asked to recruit women attending for a booking between October 1997 and July 1998 to the study. Tower Hamlets, in east London, is one of the poorest areas in England and Wales, with an ethnically diverse population. A questionnaire enquiring about age, employment, level of education, use of folic acid in their current pregnancy, understanding of the benefits of folic acid and self-described ethnic group was administered verbally immediately before the booking appointment to those women who agreed to participate. RESULTS: Completed questionnaires were received on 249 women. Univariate analysis showed that white women were 5.7 [95% confidence interval (CI) 2.5, 13.2] times more likely to have taken folic acid supplements before conception than Bangladeshi women. Having controlled for the variables, age, school leaving age, social class, parity, planned pregnancy and 'heard of folic acid', ethnic status remained a significant predictor of taking folic acid, with the odds ratio dropping to 5.2 with a 95% CI (1.1, 25.2). CONCLUSION: The Bangladeshi community in the UK have been shown to have poor access to health information sources, which is consistent with the results of this survey, which shows that a simple and important message has not been acted upon equally by white and Bangladeshi women in east London. This survey lends support to the view that resources and innovative forms of health promotion are needed to ensure that ethnic minority groups have adequate access to health promotion messages.

Adult↗
PubMed1999

Evaluation of two time-specific back pain outcome measures.

STUDY DESIGN: Postal questionnaire to individuals with back pain. OBJECTIVE: To assess the acceptability, validity, and reliability of two existing back pain outcome measures, the Roland-Morris Questionnaire and the Von Korff scales, modified to measure the preceding 4 weeks. SUMMARY OF BACKGROUND DATA: The ideal outcome measure for studies of low back pain and disability remains elusive. Most existing measures assess current pain and disability. Measuring these factors over a preceding 4-week period may be more appropriate. METHODS: Individuals with back pain identified in a community survey were asked to complete the modified questionnaires. Validity was assessed by comparison with the Medical Outcome Study Short Form 36 and two general comparator questions on self-reported pain and disability. Repeatability was assessed using retest questionnaires. RESULTS: Completed questionnaires were returned by 95 individuals with chronic back pain. The modified Roland-Morris Questionnaire and Von Korff pain and Von Korff disability scales were completed satisfactorily by 83 (87%), 89 (94%), and 87 (92%) participants, respectively. Mean scores of the modified measures changed significantly and in a predictable manner with increasing ratings of pain and disability. They also correlated with aspects of the Medical Outcome Study Short Form 36 questionnaire. Retest data suggest that these measures are repeatable. The modified Roland-Morris Questionnaire provided adequate analyzable data only if missing values were imputed, and it explained less of the variance in the comparator questions than the modified Von Korff scales. CONCLUSIONS: The modified Von Korff scales were completed easily and appear to be valid and repeatable in this format.

Adult↗
PubMed1997

Availability of services to treat patients with acute low back pain.

Guidelines for the management of acute low back pain were published in 1994. This national survey, conducted soon after, showed that the availability of services for general practitioners (GPs) to treat acute back pain fell short of the guideline recommendations. A repeat survey will be performed to measure the impact of guideline publication and dissemination.

Acute Disease↗
PubMedDate not supplied

How to do safe sternal reentry and the risk factors of redo cardiac surgery: a 21-year review with zero major cardiac injury.

OBJECTIVES: Resternotomy is a common part of cardiac surgical practice. Associated with resternotomy are the risks of cardiac injury and catastrophic hemorrhage and the subsequent elevated morbidity and mortality in the operating room or during the postoperative period. The technique of direct vision resternotomy is safe and has fewer, if any, serious cardiac injuries. The technique, the reduced need for groin cannulation and the overall low operative mortality and morbidity are the focus of this restrospective analysis. METHODS: The records of 495 patients undergoing 546 resternotomies over a 21-year period to January 2000 were reviewed. All consecutive reoperations by the one surgeon comprised patients over the age of 20 at first resternotomy: M:F 343:203, mean age 57 years (range 20 to 85, median age 60). The mean NYHA grade was 2.3 [with 67 patients (I), 273 (II), 159 (III), 43 (IV), and 4 (V classification)] with elective reoperation in 94.6%. Cardiac injury was graded into five groups and the incidence and reasons for groin cannulation estimated. The morbidity and mortality as a result of the reoperation and resternotomy were assessed. RESULTS: The hospital/30 day mortality was 2.9% (95% CI: 1.6%-4.4%) (16 deaths) over the 21 years. First (481), second (53), and third (12) resternotomies produced 307 uncomplicated technical reopenings, 203 slower but uncomplicated procedures, 9 minor superficial cardiac lacerations, and no moderate or severe cardiac injuries. Direct vision resternotomy is crystalized into the principle that only adhesions that are visualized from below are divided and only sternal bone that is freed of adhesions is sewn. Groin exposure was never performed prophylactically for resternotomy. Fourteen patients (2.6%) had such cannulation for aortic dissection/aneurysm (9 patients), excessive sternal adherence of cardiac structures (3 patients), presurgery cardiac arrest (1 patient), and high aortic cannulation desired and not possible (1 patient). The average postop blood loss was 594 mL (95% CI:558-631) in the first 12 hours. The need to return to the operating room for control of excessive bleeding was 2% (11 patients). Blood transfusion was given in 65% of the resternotomy procedures over the 21 years (mean 854 mL: 95% CI 765-945 mL) and 41% over the last 5 years. CONCLUSIONS: The technique of direct vision resternotomy has been associated with zero moderate or major cardiac injury/catastrophic hemorrhage at reoperation. Few patients have required groin cannulation. In the postoperative period, there was acceptable blood loss, transfusion rates, reduced morbidity, and moderate low mortality for this potentially high risk group.

Adult↗
PubMedDate not supplied

Experiences with redo aortic valve surgery.

OBJECTIVES AND METHODS: Reoperations are an integral part of a cardiac surgeon's practice. We share our experience of 546 reoperations over the last 21 years to January 2000, with the focus directed towards the timing of reoperation, reducing the mortality and morbidity of reoperation and rereplacement aortic valve surgery, and understanding the important risk factors. In addition, the precise technical steps that facilitate careful successful explantation of various devices (allograft, stented and stentless xenografts, and mechanical valves) are detailed. RESULTS: Optimal planned reoperation before deterioration to New York Heart Association Class III/IV levels and before unfavorable cardiac and comorbidity general system failure occurs has produced low mortality and morbidity as compared with first operation results. However, unfavorable delays and late rereferral result in mortality rates of up to 22% for emergency redo AVR for degenerated bioprostheses. CONCLUSION: Cardiac surgical units have the opportunity to establish a closer patient-surgeon relationship, which favors, when necessary, the optimal timing of reoperation. Knowledge of the more important risk factors and adherence to specific technical steps at explantation of various devices enhances satisfactory reoperation outcomes.

Aortic Valve↗