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Biomedical subjects

P Wilkinson

Publications and source records attributed to P Wilkinson.

At least 55 records · Page 3Linked to original sources

Tuberculosis in health service employees in Northern Ireland.

Tuberculosis can be transmitted from patients to health care workers. However, where the incidence of tuberculosis is low, and good infection control practices exist, the risk of health care workers acquiring the disease is likely to be small. The objective of this study was to determine the rate of notification of tuberculosis in health care workers in Northern Ireland compared with the general population. Information from the statutory tuberculosis notification forms for the period 1982-1991 was entered on to a computer database. Those patients involved in health care occupations were identified and age and sex standardized incidence rates were calculated. The overall notification rate for tuberculosis was 7.4 cases per 100,000 of general population. There was no significant increase in notification of tuberculosis among health care workers [standardized incidence ratio: 126% (95% CI 91-170)]. No cases were diagnosed as a result of screening methods performed during employment. It was concluded that health care workers in Northern Ireland did not have a significantly increased incidence of tuberculosis compared with the general population over the 10-year period studied. This suggests that the risk of transmission from patients to health care workers is negligible in the setting of a low general incidence of tuberculosis and good infection control practice. Under these circumstances, the present findings support the cessation of routine screening of health care workers.

Contact Tracing↗

Prognostic factors for patients with advanced seminoma treated with platinum-based chemotherapy.

Prognostic factors for 3-year progression-free survival (PFS) were defined in 286 patients with advanced seminoma treated with cisplatin-based chemotherapy at 10 European oncology units (no prior treatment: 236; prior radiotherapy: 50). Previously irradiated patients displayed a 69% PFS as compared to 87% in those presenting with advanced seminoma at the time of diagnosis (P = 0.009). In the univariate analysis, the extent and site of disease before chemotherapy and the level of serum LDH (< 2.0 versus > or = 2.0 x upper limit of normal) correlated with PFS in previously non-irradiated patients, but not in patients with prior radiotherapy. The multivariate analysis was, therefore, restricted to previously non-irradiated patients. The presence of non-pulmonary visceral metastases and a serum LDH level of > or = 2 x normal (N) proved to be independent prognostic factors. Based on these variables, two prognostic models were constructed and validated in an external data set of 166 comparable patients. For clinical use, Model 2 is recommended. The good-prognosis group comprises non-irradiated patients with stage II seminoma and any LDH level at presentation, or stage III and IV patients (with lung metastases only) whose serum LDH level is < 2 x N. These patients display a 94% 3-year PFS. The poor prognosis group includes all other patients with a 56% PFS. With this prognostic model, individualisation of the therapeutic approach may be considered in patients with advanced seminoma and a high risk of chemotherapy-related toxicity.

Adult↗

Glutathione reduces the toxicity and improves quality of life of women diagnosed with ovarian cancer treated with cisplatin: results of a double-blind, randomised trial.

BACKGROUND: Early clinical trials have suggested that glutathione (GSH) offers protection from the toxic effects of cisplatin. PATIENTS AND METHODS: One hundred fifty-one patients with ovarian cancer (stage I-IV) were evaluated in a clinical trial of cisplatin (CDDP) +/- glutathione (GSH). The objective was to determine whether GSH would enhance the feasibility of giving six cycles of CDDP at 100 mg/m2 without dose reduction due to toxicity. RESULTS: When considering the proportion of patients receiving six courses of CDDP at any dose, GSH produced a significant advantage over control--58% versus 39%, (P = 0.04). For these patients there was a significant difference between the reduction in creatinine clearance for GSH treated patients compared with control--74% versus 62% (P = 0.006). Quality of life scores demonstrated that for patients receiving GSH there was a statistically significant improvement in depression, emesis, peripheral neurotoxicity, hair loss, shortness of breath and difficulty concentrating. As an indication of overall activity, these patients were statistically significantly more able to undertake housekeeping and shopping. Clinically assessed response to treatment demonstrated a trend towards a better outcome in the GSH group (73% versus 62%) but this was not statistically significant (P = 0.25). CONCLUSIONS: The results demonstrate that adding GSH to CDDP allows more cycles of CDDP treatment to be administered because less toxicity is observed and the patient's quality of life is improved.

Adult↗

Attenuation or absence of circadian and seasonal rhythms of acute myocardial infarction.

OBJECTIVES: To examine the circadian, seasonal, and weekly rhythms of acute myocardial infarction, and to identify subgroups in whom the rhythms are attenuated or absent to provide further information about the mechanisms of the rhythms and the processes responsible for triggering plaque events. DESIGN AND SETTING: Prospective, observational study in a general hospital. PATIENTS AND METHODS: 1225 consecutive patients admitted to a coronary care unit with acute myocardial infarction were studied. Admission rates were calculated according to the hour of the day (circadian rhythm), day of the week (weekly rhythm), and month of year (seasonal rhythm). The data were analysed for variations within the whole group and within subgroups. RESULTS: A weekly rhythm of acute myocardial infarction could not be demonstrated but there was a trend towards higher admission rates at the beginning of the week. However, the time of onset of symptoms showed significant circadian variation for the group as a whole, peaking in the morning (P = 0.006), against an otherwise fairly constant background rate. Subgroup analysis showed complete absence of the circadian rhythm in patients who were diabetic, South Asian, or taking beta blockers or aspirin on admission. Significant seasonal variation in admission rates was also demonstrated for the group as a whole with a winter peak and a summer trough (P = 0.009). Again, no seasonal rhythm could be demonstrated in patients who were diabetic, South Asian, or taking beta blockers or aspirin on admission. CONCLUSIONS: The absence of circadian and seasonal rhythms of acute myocardial infarction in almost identical subgroups suggests that common mechanisms are involved in driving these rhythms. The autonomic nervous system is a likely candidate because the rhythms were absent in patients taking beta blockers as well as in patients in whom derangement of autonomic function commonly occurs.

Adrenergic beta-Antagonists↗

Cancer incidence and mortality around the Pan Britannica Industries pesticide factory, Waltham Abbey.

OBJECTIVES: To examine the incidence and mortality of cancer near the Pan Britannica Industries factory, Waltham Abbey, after reports of a possible cluster of all cancers and brain cancer in the vicinity. METHOD: Small area study of cancer incidence 1977-89, and mortality 1981-92, within a 7.5 km radius of the factory site. Postcoded cancer registrations and deaths in the study area were extracted from national data sets held by the Small Area Health Statistics Unit and compared with expected numbers computed by applying national rates stratified for age, sex, and deprivation to the local population (1981 and 1991 censuses). Observed/ expected (O/E) ratios were examined from 0-1 km and 0-7.5 km of the plant, and tests applied for a decline in relative risk with distance up to 7.5 km. RESULTS: There were 12,859 incidence cancers (1977-89) from 0-7.5 km (O/E ratio 1.04; 95% confidence interval (95% CI) 1.02 to 1.06) and 385 from 0-1 km (O/E 1.10; 1.00 to 1.22). There was an excess of skin melanoma from 0-1 km based on 11 cases (O/E 2.13; 1.06 to 3.80), and an excess from 0-7.5 km of cancer of the lung, stomach and pancreas combined, and prostate (O/Es ranged from 1.09 to 1.13). Only the findings from lung cancer were suggestive of a decline in risk with distance, especially in the later period (1982-9). There were 9196 cancer deaths (1981-92) from 0-7.5 km (O/E 1.04; 95% CI 1.02 to 1.06) and 308 from 0-1 km (O/E 1.24; 1.11 to 1.39); and 25507 non-cancer deaths (O/E 1.02; 1.01 to 1.04) from 0-7.5 km and 745 (O/E 1.14; 1.06 to 1.22) from 0-1 km. There was evidence of a decline in mortality with distance for all cancers combined, lung cancer (P = 0.001 for each), and colorectal cancer (P < 0.05), and also for non-cancers (P = 0.001). Proportional mortality analyses suggested a decline in risk with distance for lung cancer (P = 0.003) but not for all cancers or the site specific cancers examined. There was no evidence of an excess in the incidence or mortality from brain cancer. For cancer mortality in the inner-most wards, the findings were, for the most part, well within the range of variation across the region as a whole. CONCLUSIONS: The study provides limited and inconsistent evidence for a localised excess of cancer in the vicinity of the PBI plant. At present, further investigation does not seem warranted other than continued surveillance of mortality and cancer incidence in the locality.

Adolescent↗

Does the duration of illness before treatment affect the time taken to recover on treatment in severely depressed women?

This study examines the link between duration of depression before treatment is introduced and the duration of depressive illness after treatment in a population of 59 female psychiatric inpatients. Most women were suffering with severe depression and the majority had had previous depressive illnesses. Calculation of the rank order correlation coefficient demonstrated no significant correlation between the duration of depression before initiation of treatment and the duration after treatment was introduced. This finding is discussed in relation to other relevant studies.

Adult↗

Comparison of case fatality in south Asian and white patients after acute myocardial infarction: observational study.

OBJECTIVE: To compare mortality in south Asian (Indian, Pakistani, and Bangladeshi) and white patients in the six months after hospital admission for acute myocardial infarction. DESIGN: Observational study. SETTING: District general hospital in east London. PATIENTS: 149 south Asian and 313 white patients aged < 65 years admitted to the coronary care unit with acute myocardial infarction from 1 December 1988 to 31 December 1992. MAIN OUTCOME MEASURE: All cause mortality in the first six months after myocardial infarction. RESULTS: The admission rate in the south Asians was estimated to be 2.04 times that in the white patients. Most aspects of treatment were similar in the two groups, except that a higher proportion of the south Asians received thrombolytic drugs (81.2% v 73.8%). After adjustment for age, sex, previous myocardial infarction, and treatment with thrombolysis or aspirin, or both, the south Asians had a poorer survival over the six months from myocardial infarction (hazard ratio 2.02 (95% confidence interval 1.14 to 3.56), P = 0.018), but a substantially higher proportion were diabetic (38% v 11%, P < 0.001), and additional adjustment for diabetes removed much of their excess risk (adjusted hazard ratio 1.26 (0.68 to 2.33), P = 0.47). CONCLUSION: South Asian patients had a higher risk of admission with myocardial infarction and a higher risk of death over the ensuing six months than the white patients. The higher case fatality among the south Asians, largely attributable to diabetes, may contribute to the increased risk of death from coronary heart disease in south Asians living in Britain.

Adult↗

Is lung cancer associated with asbestos exposure when there are no small opacities on the chest radiograph?

This study was designed to test the hypothesis that the risk of lung cancer from asbestos exposure is confined to persons with radiographic evidence of pulmonary fibrosis. Occupational and smoking histories were obtained from 271 patients with a confirmed diagnosis of primary lung cancer and 678 referents (279 with other respiratory disease and 399 with cardiac disease). Histories were reviewed blind to assess the timing, duration, and probability of exposure to asbestos. To allow for a lag between asbestos exposure and the development of lung cancer, subjects were classified by the time they had spent in an occupation entailing definite or probable exposure more than 15 years before diagnosis. The presence and extent of fibrosis was assessed blindly from chest radiographs by three readers and scored for small opacities with the ILO 1989 International Classification of Radiographs of the Pneumoconioses. 93 (34.3%) cases had worked in an occupation with definite or probable asbestos exposure compared with 176 (25.8%) referents (crude odds ratio for lung cancer 1.49, 95% CI 1.09-2.04). After adjustment for age, sex, smoking history, and area of referral, the odds ratio (95% CI) was 2.03 (1.00-4.13) in the subgroup of 211 with a median ILO score for small parenchymal opacities of 1/0 or more, and 1.56 (1.02-2.39) in the 738 with a score of 0/1 or less (ie, those without radiological evidence of pulmonary fibrosis). These results suggest that asbestos is associated with lung cancer even in the absence of radiologically apparent pulmonary fibrosis.

Aged↗

Prognosis in acute myocardial infarction: comparison of patients with diagnostic and nondiagnostic electrocardiograms.

Prognosis in acute myocardial infarction has been compared in patients with and without diagnostic ECGs. Of 817 patients, 89.4% had ST elevation, 2.4% had left bundle branch block, and 8.2% had no ST elevation. Patients without ST elevation had a hospital mortality rate of 3.0% compared with 14.0% and 40.0%, respectively, in patients with ST elevation and left bundle branch block (p = 0.0001). Event-free survival at 6 months in patients without ST elevation was 85.6% (74.1% to 92.3%), compared with 72.9% (69.4% to 76.0%) and 31.0% (12.0% to 52.3%) in patients with ST elevation and left bundle branch block (p < 0.001). The excess risk associated with ST elevation was largely attributable to the severity of infarction: after adjustment for Q-wave development and heart failure, the hazard ratio fell from 2.24 (1.43 to 4.38) to 1.76 (0.86 to 3.59). In conclusion, acute myocardial infarction has a considerably better prognosis when it is unassociated with ST elevation or left bundle branch block. This finding may have important implications for interventional management.

Aged↗

A qualitative study to establish the self-perceived needs of family members of patients in a general intensive care unit.

Admission to an intensive care unit (ICU) invariably causes a considerable degree of distress and anxiety to both patient and family. If we profess to deliver holistic care then it is essential that intensive care nurses are able to identify the specific needs of family members and provide appropriate supportive interventions. This small study was designed to gain the perspectives of the families. Through unstructured interviews participants were invited to discuss their experiences of visiting a critically ill relative, particularly in relationship to their own needs. Interviews were tape-recorded with permission and subsequently transcribed. Thematic content analysis adapted from Glaser & Strauss' 'grounded theory' approach (1967) by Burnard (1991) occurred, with formation of six categories, exemplified by verbatim quotations. The study may contribute towards a framework for preventative, supportive and therapeutic intervention with family members in the intensive care setting.

Attitude to Health↗

Early discharge after acute myocardial infarction: risks and benefits.

BACKGROUND: Thrombolytic treatment reduces mortality in patients with acute myocardial infarction but is associated with recurrent thrombotic events after admission, and it is unclear whether current practices of early hospital discharge are safe. Timing of first major adverse events (death, reinfarction, unstable angina, secondary ventricular fibrillation) in the early post-infarction period was studied to determine the risks. DESIGN: Follow up study. PATIENTS: 608 consecutive patients (447 men and 161 women) with confirmed myocardial infarction who were admitted to the coronary care unit of a district general hospital between January 1989 and December 1991. Clinical details, including the development of left ventricular failure and in hospital adverse events, were recorded prospectively. Follow up for out of hospital adverse events was carried out by review of the case notes, postal questionnaire, and where necessary, by telephone contact with the patient and his general practitioner. RESULTS: The risk (95% confidence interval) of major adverse events in the first 10 days was 32.3% (26.3 to 39.4%) in patients with heart failure and 7.3% (5.1 to 9.2%) in those without. Smoothed estimates of the event rate in patients without heart failure decreased from 5.9 events/1000 persons/day on day 6 to 3.4 events/1000 persons/day on day 10 and 0.9 events/1000 persons/day on day 21. The corresponding cumulative risk estimates suggest that about 11 in every 1000 patients suffer a major, but often unpreventable, adverse event on day 6 or 7 after admission, and 23 in every 1000 do so between days 6 and 10. CONCLUSIONS: The point at which the risk to the individual becomes acceptably low is a matter of judgement, but the risk of a major adverse event declines rapidly after a heart attack, and particularly for patients without heart failure discharge within a few days may be appropriate. Prolonging stay unnecessarily may use resources which could be more effectively used to treat cardiac disease in other ways.

Adult↗

Acute myocardial infarction in women: survival analysis in first six months.

OBJECTIVE: To examine the influence that being female has on the outcome of acute myocardial infarction. DESIGN: Observational follow up study. SETTING: London district general hospital. PATIENTS: 216 women and 607 men with acute myocardial infarction admitted to a coronary care unit from 1 January 1988 to 31 December 1992. MAIN OUTCOME MEASURES: All cause mortality and recurrent ischaemic events in the first six months. RESULTS: Event free survival (95% confidence interval) at six months was 63.3% (56.3% to 69.4%) in women and 76.1% (72.4% to 79.4%) in men, P < 0.001. The difference was confined to the first 30 days but thereafter the hazard plots for women and men converged, with reduction of the hazard ratio from 2.36 (1.70 to 3.27) to 0.81 (0.44 to 1.48). Women were older, but their excess risk persisted after adjustment for age, other baseline variables, and indices of severity of infarction (hazard ratio 1.53 (1.09 to 2.15), P = 0.015). Women tended to be treated with thrombolysis less commonly than men but the difference was small. Substantially fewer women than men, however, were discharged taking beta blockers (23.3% v 41.4%, P < 0.001), and although additional adjustment for discharge treatment did not further reduce the point estimate of the hazard ratio (1.84 (0.89-3.83)), the 95% confidence interval was wide and statistical significance was lost. CONCLUSIONS: Women with acute myocardial infarction have a worse prognosis than men but the excess risk is confined to the first 30 days and is only partly explained by age and other baseline variables. The tendency for women to receive less vigorous treatment than men must be remedied before gender can be considered to be an independent determinant of risk.

Adrenergic beta-Antagonists↗

Relative value of clinical variables, treadmill stress testing, and Holter ST monitoring for postinfarction risk stratification.

The aim of this study was to compare the roles of clinical assessment, treadmill stress testing, and Holter ST analysis for postinfarction risk stratification in patients treated with thrombolysis. The study group consisted of 256 consecutive patients, all of whom underwent Holter ST monitoring early (mean 83 hours, range 48 to 180) after admission. Of these, 12 were excluded from the analysis either because Holter recordings were of insufficient quality (n = 6), or because reinfarction occurred within 24 hours of monitoring (n = 6). In the remaining 244 patients, 43 sustained a recurrent event (death, reinfarction, unstable angina) over the 8-month (range 3 to 12) follow-up period, and an additional 14 patients required revascularization. At multivariate event-free survival analysis, Killip class > or = 2 and Holter ST shift were independently predictive of the outcome. The strongest predictor was Holter ST shift at a cumulative duration of > 60 minutes. Of the 232 patients eligible for stress testing (12 sustained an event between Holter monitoring and the scheduled stress test), 196 were able to perform the test. The variable "inability to perform a stress test" was not independently predictive of outcome and did not influence the multivariate analysis. When clinical, Holter, and stress test variables were taken into account in patients who performed a stress test, Killip class was the only independent predictor of outcome (event-free survival). When revascularization was included as an end point, Holter ST shift was the only independent predictor of outcome. In conclusion, a significant proportion of recurrent events after thrombolysis occurs very early, before stress testing can be performed.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Reexamination of the role of endogenous opiates in silent myocardial ischemia.

OBJECTIVES: This study was designed to examine the role of beta-endorphin and met-enkephalin in the pathophysiology of silent myocardial ischemia, with emphasis on their role in the physiologic response to stress. BACKGROUND: Silent myocardial ischemia is more common in patients whose perception of pain is reduced. Whether endogenous opiates can contribute to this process remains uncertain largely because of the conflicting findings of previous studies. METHODS: Forty-three patients with coronary artery disease and ischemia on treadmill stress testing underwent electrical pain tests and exercise treadmill tests during naloxone and placebo infusion in a randomized, double-blind crossover study. Thirty-one patients developed angina during both treadmill tests (group A), and 12 had silent ischemia (group B). Plasma beta-endorphin, metenkephalin, epinephrine, norepinephrine and cortisol were measured before and after exercise in a subgroup of 17 patients. RESULTS: Naloxone reduced electrical pain tolerance (1.40 +/- 0.10 [mean +/- SEM] vs. 1.72 +/- 0.19 mA, p = 0.04) but did not affect the time to angina in group A (260 +/- 20 vs. 248 +/- 20 s, p = 0.72) or induce angina in group B patients. Beta-endorphin and met-enkephalin levels during placebo infusion were not significantly different in groups A and B at baseline and after exercise, although beta-endorphin levels were significantly increased during naloxone infusion, confirming effective opiate receptor blockade. Norepinephrine and cortisol increased with exercise, but catecholamines and cortisol were similar in both groups and were unaffected by naloxone. CONCLUSIONS: Beta-endorphin and met-enkephalin were similar in patients with painful and silent ischemia, and naloxone infusion did not influence anginal symptoms despite effective opiate receptor blockade and a reduction in somatic pain tolerance. These findings suggest that endogenous opiates do not play an important role in modulating symptoms in myocardial ischemia. The increase in beta-endorphin with exercise that coincided with an increase in plasma cortisol is most likely due to its release from the anterior pituitary gland as part of the physiologic stress response.

Double-Blind Method↗

Problem-solving therapy in the treatment of unexplained physical symptoms in primary care: a preliminary study.

We describe a pilot study of a simple psychological treatment based on reattribution techniques and problem-solving. The treatment was administered to a consecutive series of patients (N = 11) presenting in primary care with unexplained physical symptoms. The findings suggest that the treatment is both feasible and acceptable. Finally we suggest selection criteria for those patients who may benefit from the treatment. This needs further evaluation in a randomized, controlled trial.

Adolescent↗