Sham radiation in clinical trials assessing radiotherapy for exudative age-related macular degeneration

BACKGROUND: To evaluate the effectiveness of sham radiation treatments in masking patients to their randomization group in the Radiation of Age-Related Macular Degeneration (ROARMD) Study. METHODS: Patients with choroidal neovascularization complicating age-related macular degeneration were randomized to a treatment (RAD) group that received external beam irradiation (seven treatment sessions) or to a control (SHAM) group that received sham radiation (one sham treatment session). During a telephone survey, 62 of 73 randomized patients responded to the following questions: Do you think you received radiation? Why do you feel that way? Did the vision in your study eye worsen after enrollment? RESULTS: Eighty-one percent of the RAD group and 59% of the SHAM group thought that they had received radiation. In patients who thought that their vision had stabilized or improved, 82% thought that they had received radiation. In patients who thought that their vision was worse, only 39% thought that they had received radiation. In 54% of patients, subjective perception of vision influenced their guess as to whether they received radiation. CONCLUSIONS: Subjective patient perception of visual outcome was the most influential variable for masking. Variation between radiation treatment and sham session techniques, such as equipment used and duration of treatments, played a lesser role in the masking of patients. Seven treatment days correlated with a higher number of patients who thought that they had received radiation. Although our procedures do not strictly mask the two groups, one sham radiation session was effective in keeping patients guessing their randomization group.     

A Study of Lung Function and Chest Radiographs in Men Exposed to Zirconium Compounds

Men working with zirconium compounds at one site in the Northof England have been monitored since 1975 to evaluate effectson the lung of exposure (mainly<10mg/m³) over many years.Chest radiographs (in 1975, 1978, and 1982) and lung functionmeasurements (from 1975–1988) were carried out on allmen (178) known to have worked with the compounds and an estimateof cumulative exposure was computed from job title and likelyexposures in each era. No evidence was found that zirconiumexposure resulted in abnormal chest radiographs or impairedpulmonary function. Received       21 April 1995 Accepted       25 January 1996     

Thallium-201 myocardial perfusion scintigrams in the evaluation of aorto-coronary saphenous bypass surgery.

The effect of aorto-coronary bypass graft surgery (CBG) upon regional myocardial perfusion (RMP) was studied in 23 patients using thallium-201 myocardial perfusing imaging after exercise. We compared the changes in RMP with the clinical status and ECG's during graded treadmill exercise (GTX) before and after CBG. After CBG, the New York Heart Association's "functional class" improved from 3.2 +/- 0.1 (mean +/- SE) to 1.2 +/- 0.2, p less than 0.005. The GTX performance of the patients was also significantly improved postoperatively as judged by the total exercise time (11.7 +/- 0.6 min postop, compared with 7.2 +/- 0.5 min preop; p less than 0.005). Postoperative improved Tl-201 scintigrams were observed in 19 patients, but in only nine patients did the perfusion distribution return to normal. Thus, Tl-201 exercise scintigrams following CBG demonstrate improved RMP in most patients. Failure of regional myocardial perfusion to improve postoperatively, however, does not preclude marked alleviation of angina and improved exercise tolerance.     

Health status of cable splicers with low-level exposure to lead: results of a clinical survey

The results of a cross-sectional clinical field survey of 90 telephone cable splicers are presented. Despite the rare occurrence of clinically overt lead poisoning among cable splicers, the observed prevalence of symptoms was 29% for lead-associated central nervous system symptoms and 21% for gastrointestinal symptoms. These two groups of symptoms were directly related to zinc protoporphyrin (ZPP) levels but no relationship was found between them and blood lead concentrations. Only 5% of the workers had significantly elevated blood lead levels (greater than 40 microgram/100ml). Because of the intermittent lead exposure encountered in this trade, individuals were identified with "normal" blood lead levels associated with "elevated" zinc protoporphyrin concentrations, indicating the difference in biological significance between exposure-(blood lead) and biological-response tests (ZPP). Suggestion is made that both types of diagnostic tests be utilized in the medical surveillance of lead-exposured workers.     

Using the stages of change model to increase the adoption of physical activity among community participants

PURPOSE. This study examined the use of the stages of change model to design an exercise intervention for community volunteers. DESIGN. The "Imagine Action" campaign was a community-wide event incorporating the involvement of local worksites and community agencies. Community members registering for the campaign were enrolled in a six-week intervention program designed to encourage participation in physical activity. SUBJECTS. Six hundred and ten adults aged 18 to 82 years old enrolled in the program. Seventy-seven percent of the participants were female and the average age was 41.8 years (SD = 13.8). SETTING. The campaign was conducted in a city with a population of approximately 72,000 and was promoted throughout community worksites, area schools, organizations, and local media channels. MEASURES. One question designed to assess current stage of exercise adoption was included on the campaign registration form as were questions about subject name, address, telephone number, birthdate, and gender. INTERVENTION. The intervention included written materials designed to encourage participants to initiate or increase physical activity, a resource manual describing activity options in the community, and weekly "fun walks" and "activity nights." RESULTS. A Stuart-Maxwell test for correlated proportions revealed that subjects were significantly more active after the six-week intervention. Sixty-two percent of participants in Contemplation became more active while 61% in Preparation became more active. CONCLUSIONS. Most participants increased their stage of exercise adoption during the six-week intervention. This study provides preliminary support for use of the stages of change model in designing exercise interventions.     

Effect of autologous blood donation in patients undergoing elective spine surgery.

Autologous blood predeposit before elective surgery is a rapidly expanding transfusion practice. A 3-year analysis of an autologous blood predeposit program was conducted to assess its impact on orthopaedic spine surgery. It was concluded that, first, autologous blood donation has resulted in a reduction of homologous blood transfusions in patients undergoing elective spine procedures from 26% to 13% (P = .02). Second, autologous blood preoperative donation in elective spine surgery has increased significantly, so that autologous blood as an alternative to homologous blood transfusion now represents a standard of practice for elective spine surgery at the institution included in the study. Third, limitations of preoperative autologous blood procurement suggest that application of additional blood conservation interventions as alternatives to homologous blood would be important contributors to achieving "bloodless" surgery in this setting.     

Auditing and improving notification and chemoprophylaxis in bacterial meningitis.

STUDY OBJECTIVE--The aim was to audit, against agreed standards, the control of bacterial meningitis, in particular completeness of notification and appropriateness of distribution of chemoprophylaxis to contacts; and to implement appropriate changes and monitor their impact. DESIGN--The first phase involved determination, for the years 1983 and 1984, of completeness of notification by comparison with a comprehensive case register. Information about chemoprophylaxis was obtained from case notes, questionnaires to general practitioners and other records. The second phase involved introducing a programme of clinician education in the hospital with the poorest observed notification performance and re-examining performance during 1988. Districtwide education regarding chemoprophylaxis was undertaken and the situation re-examined in 1988. SETTING--The study took place in Mid Glamorgan Health Authority (population 536,000), with four acute hospitals. POPULATION--Consisted of all the residents of Mid Glamorgan Health Authority. MAIN RESULTS--During the first phase of the audit only 28 out of 79 cases of bacterial meningitis were notified (35%). Performance in one hospital was significantly worse than in the other three. Chemoprophylaxis was distributed to 20 out of 26 (77%) cases of meningococcal meningitis but inappropriate drugs were used in four cases and prophylaxis was distributed more widely than is recommended in 10 cases. In the phase 2 re-examination, a significant improvement in notification was observed in the hospital where special measures were taken, with no change in a "control" hospital. Chemoprophylaxis improved throughout the District, although rifampicin continued to be distributed too widely. CONCLUSIONS--As a result of this audit, measurable improvements in both infectious disease notification and chemoprophylaxis practice were obtained by the education of clinicians. The study provides a good example of a completed audit cycle in public health medicine.     

Retroperitoneoscopic excision of phaeochromocytoma--haemodynamic events, complications and outcome

Over a period of 15 months, 11 patients with phaeochromocytoma underwent retroperitoneoscopic excision of their tumours. Five patients had bilateral tumours. All patients underwent thorough preoperative evaluation and preparation with alpha- and beta-blockade. In the majority of the patients a hypertensive response was seen during generation of pneumoretroperitoneum. However, the period of tumour dissection and excision was devoid of large haemodynamic fluctuations. The average time taken was 3.5 to 4 hours per gland. Blood loss in successful laparoscopic excision averaged 240 ml (range 120 to 700 ml). In these patients satisfactory postoperative analgesia could be provided with intramuscular pethidine or intramuscular diclofenac sodium. In three patients the procedure had to be converted to open laparotomy due to haemorrhage. All three patients had preoperative radiological evidence of inferior vena cava and aortic involvement. Patient selection plays an important role in a successful outcome.