A cohort analysis of excess mortality in asthma and the use of inhaled beta-agonists

The association between the use of inhaled beta-agonists and the risk of death and near-death from asthma has previously been reported. It was based on a nested case-control study of 129 cases and 655 control subjects selected from a cohort of 12,301 users of asthma drugs followed during the period 1980 through 1987. In this paper we examine the question of asthma and non-asthma mortality using data from the entire cohort of 12,301 asthmatics. There were 46 asthma and 134 non-asthma deaths in this cohort, for which there were 47,842 person-years of follow-up. The overall rate of asthma death was 9.6 per 10,000 asthmatics per year. This rate varied significantly according to the use of fenoterol, albuterol, or oral corticosteroids in the prior 12 months and the number of asthma hospitalizations in the prior 2 years. The rate decreased significantly, by 0.6 asthma deaths per 10,000 asthmatics per year over the study period, after controlling for the effect of the four other risk factors. It also increased significantly with the use of all beta-agonists, and more so for fenoterol than for albuterol, although this difference was partly explained by the dose inequivalence of the two drugs. Change-point dose-response curves showed that the risk of asthma death began to escalate drastically at about 1.4 canisters (of 20,000 micrograms each) per month of inhaled beta-agonist, the recommended limit. For non-asthma death, the overall rate of 28 deaths per 10,000 asthmatics per year was not related to the use of inhaled beta-agonists.(ABSTRACT TRUNCATED AT 250 WORDS)

Controlled study of fluconazole in the prevention of fungal infections in neutropenic patients with haematological malignancies and bone marrow transplant recipients

The efficacy and safety of oral fluconazole versus a polyene regimen in preventing mycoses in neutropenic patients was compared. Patients with haematological malignancy or bone marrow transplantation received as antifungal prophylaxis either fluconazole 200 mg daily or a regimen consisting of clotrimazole trouches 10 mg twice daily with mycostatin, 500,000 I.U. four times daily, benadryl and cepacol mouthwash. Ninety patients at risk for fungus infection were evaluable. Four of 42 patients (9.5%; confidence interval 2%-23%) on fluconazole and 17 of 48 patients (35.4%; confidence interval 22%-52%) (p < 0.01) on the clotrimazole regimen developed a clinically significant fungal infection, including 3 (7.1%) and 11 (22.9%) patients respectively who had severe fungal infection, mainly pulmonary aspergillosis. Death directly due to a fungal infection within 100 days of the start of prophylaxis occurred in 2 of 42 patients (4.8%) and 9 of 48 patients (18.8%) respectively (p < 0.06). Kaplan-Meier analysis showed that the chance of survival on fluconazole was statistically greater than for the clotrimazole regimen (p < 0.04). A decrease of candidal colonisation of the gastrointestinal and genitourinary tracts occurred only in patients receiving fluconazole. No significant toxicity occurred. A 200 mg daily dose of fluconazole given to these patients thus appears to be well tolerated and to provide a protective effect against the development of fungal infection and death from severe fungal disease.

Inhibition of neutrophil functions by human immunoglobulin E

Incubation of human neutrophils with human immunoglobulin (Ig) E caused dose-dependent inhibition of adhesion, phagocytosis, secretion of myeloperoxidase, and oxygen radical production. The concentrations of IgE that caused 50% inhibition of adhesion, phagocytosis, and secretion were 2 +/- 0.3, 2.16 +/- 0.21, and 1.95 +/- 0.28 ng/ml, respectively. Oxidase activation as measured by luminol-dependent chemiluminescence by the receptor-mediated N-formyl-methionyl-leucyl-phenylalanine, phorbol 12-myristate 13-acetate, or the particulate stimulus Staphylococcus aureus was inhibited by IgE with concentrations causing 50% effect of 1.2 +/- 0.13, 1.09 +/- 0.16, and 0.6 +/- 0.09 ng/ml, respectively. IgE also inhibited oxygen consumption rate and cytochrome c reduction with similar K0.5 values. The effect of IgE was unlikely to be due to nonspecific cytotoxicity because trypan blue exclusion test and the cytoplasmic marker lactate dehydrogenase revealed that the cells retained their viability after IgE treatment. Similar or higher concentrations of IgG invoked either no inhibition or a slight enhancement of neutrophil functions. Pretreatment of neutrophils with IgG failed to affect the IgE-induced inhibition. Because the effect of IgE occurs at concentrations less than those reported in hyperimmunoglobulinemia E, we propose that direct inhibition of neutrophil functions may underlie the pathogenesis of recurrent infection associated with hyperimmunoglobulinemia E.

Questionnaire assessments of recent exposure to environmental tobacco smoke in relation to salivary cotinine

The increasing evidence of the ill-health effects of environmental tobacco smoke (ETS) has prompted the search for accurate measures of exposure to ETS. The present study examined whether it was possible to enhance the ability of questionnaire-derived assessments of ETS exposure, to predict salivary cotinine. Salivary samples were obtained from 258 nonsmoking bank employees, who simultaneously answered questions detailing their exposure to second-hand smoke within the last three days. Exposure models were created, to take into account the number of smokers nearby, length of time in their presence, half-life of cotinine in bodily fluids, level of aversion to cigarette smoke and time of year. All models, including the consideration of intensity and duration of exposure combined, explained an equal amount of variance of log cotinine levels (approximately 16%). The weak relationship between questionnaire estimates of ETS exposure and cotinine, found in the present study, suggests that further investigation is needed to improve the assessment of recent ETS exposure.

Questionnaire assessments of recent exposure to environmental tobacco smoke in relation to salivary cotinine

The increasing evidence of the ill-health effects of environmental tobacco smoke (ETS) has prompted the search for accurate measures of exposure to ETS. The present study examined whether it was possible to enhance the ability of questionnaire-derived assessments of ETS exposure, to predict salivary cotinine. Salivary samples were obtained from 258 nonsmoking bank employees, who simultaneously answered questions detailing their exposure to second-hand smoke within the last three days. Exposure models were created, to take into account the number of smokers nearby, length of time in their presence, half-life of cotinine in bodily fluids, level of aversion to cigarette smoke and time of year. All models, including the consideration of intensity and duration of exposure combined, explained an equal amount of variance of log cotinine levels (approximately 16%). The weak relationship between questionnaire estimates of ETS exposure and cotinine, found in the present study, suggests that further investigation is needed to improve the assessment of recent ETS exposure.

Tracheal size is a determinant of the bronchoconstrictive response to inhaled methacholine

We hypothesized that the size of the large airways is a determinant of bronchial responsiveness to inhaled methacholine. This was investigated by measuring the relationship of tracheal size and branching angle to the bronchoconstrictive response to methacholine, in 169 male construction insulators, aged 20-50 yrs, as part of a workforce-based, cross-sectional survey of respiratory health. Bronchial responsiveness was expressed as the concentration of methacholine, inhaled for 2 min of tidal breathing, which provoked a 15% fall in forced expiratory volume in one second (FEV1). Tracheal size was assessed from tracings of standard posteroanterior chest radiographs, at full inspiration. After accounting for the effect of airway calibre (FEV1/forced vital capacity (FVC)), age, height, and pack-years of cigarette smoking, on airways responsiveness, there was a significant association (p < 0.05) between tracheal length, diameter, or surface area and the degree of bronchoconstriction obtained by inhaling methacholine. The increase in airway responsiveness with decreasing tracheal size may reflect increased deposition of methacholine, secondary to smaller cross-sectional area and greater linear velocity of air in the trachea and main bronchi.

Is the association between inhaled beta-agonist use and life-threatening asthma because of confounding by severity?

We have previously reported an increasing dose-response relationship between the regular use of beta-agonist inhalers and the risk of asthma death and near death among a cohort of 12,301 subjects who had been dispensed 10 or more prescriptions of asthma drugs from January 1980 to April 1987. That analysis was based solely on information obtained from linkable computerized data bases. Such an association might be explained in part by the tendency of patients with more severe asthma, that is, those at greatest risk for an adverse outcome, to use more beta-agonist medication. To further examine this potential confounding by severity, we gathered clinical information independently from the field on the 129 case patients and their 655 control patients from the matched case-control analysis of 12,301 subjects. In 68% of the control patients with a life-threatening episode and 75% of the matched control subjects, we obtained a valid questionnaire from at least one physician who had seen the patient during the previous 2 yr. Acceptable information on hospitalizations because of asthma was obtained in 87% of those hospitalized. Clinical features associated with an increased risk of fatal and near-fatal asthma were: a history of loss of consciousness or seizures during a previous asthma attack (odds ratio, 10.2; 95% CI, 3.9 to 26.7), a history of attacks of asthma precipitated by eating certain foods (odds ratio, 5.1; 95% CI, 2.4 to 11.1), a clinical score designed to reflect the severity of prior attacks of asthma leading to hospitalization, and prior respiratory acidosis among those in whom a blood gas determination was recorded.(ABSTRACT TRUNCATED AT 250 WORDS)

Tracheal size is a determinant of the bronchoconstrictive response to inhaled methacholine

We hypothesized that the size of the large airways is a determinant of bronchial responsiveness to inhaled methacholine. This was investigated by measuring the relationship of tracheal size and branching angle to the bronchoconstrictive response to methacholine, in 169 male construction insulators, aged 20-50 yrs, as part of a workforce-based, cross-sectional survey of respiratory health. Bronchial responsiveness was expressed as the concentration of methacholine, inhaled for 2 min of tidal breathing, which provoked a 15% fall in forced expiratory volume in one second (FEV1). Tracheal size was assessed from tracings of standard posteroanterior chest radiographs, at full inspiration. After accounting for the effect of airway calibre (FEV1/forced vital capacity (FVC)), age, height, and pack-years of cigarette smoking, on airways responsiveness, there was a significant association (p < 0.05) between tracheal length, diameter, or surface area and the degree of bronchoconstriction obtained by inhaling methacholine. The increase in airway responsiveness with decreasing tracheal size may reflect increased deposition of methacholine, secondary to smaller cross-sectional area and greater linear velocity of air in the trachea and main bronchi.

Helicobacter pylori infection in adolescents with eating disorders and dyspeptic symptoms

The potential role of Helicobacter pylori infection of the antrum as a cause of symptoms of dyspepsia in patients with eating disorders was evaluated with an assay to detect H. pylori-specific IgG in serum. H. pylori-specific optical-density readings were comparable for adolescents with eating disorders (0.133 +/- 0.063, mean +/- SD) and for two comparison groups, and were lower than readings for children with documented H. pylori infection. Symptoms referable to the gastrointestinal tract did not correlate with H. pylori status in the teenagers with eating disorders.

Both LyF-1 and an Ets protein interact with a critical promoter element in the murine terminal transferase gene

Terminal deoxynucleotidyltransferase (TdT) is a template-independent DNA polymerase that is expressed transiently during the earliest stages of B- and T-cell ontogeny. Previously, we characterized the promoter for the murine TdT gene and identified a novel DNA-binding protein, called LyF-1, that interacts with a DNA sequence element found to be critical for transcriptional activity in lymphoid cell lines. Here, we present a more detailed analysis of this 30-bp control element, called the TdT D' element, which is centered approximately 60 bp upstream of the transcription start site. We found that both the murine and human D' elements are recognized by multiple proteins, including LyF-1 and at least two Ets family proteins, Ets-1 and Fli-1. Additional protein-DNA interactions were identified through studies using unfractionated nuclear extracts, in which the D' element was apparently incorporated into a multiprotein complex, possibly containing an Ets protein as a core component. By analyzing a series of substitution mutations, two adjacent binding sites for LyF-1 were identified in the murine D' element, with the Ets protein binding site closely coinciding with the proximal, lower-affinity LyF-1 site. Transient transfection analysis with these mutations revealed that only a 10-bp region, containing precisely the Ets and proximal LyF-1 binding sites, was needed for D' activity. These results suggest an important role for an Ets family protein in the expression of the TdT gene. The role of LyF-1 is less clear; it might act in conjunction with the Ets protein bound at the D' element or it might be unnecessary for D' activity.

Respiratory symptoms in young adults should not be overlooked

The purpose of this study was to examine the relation between development of respiratory symptoms and the rate of change in ventilatory lung function in young adults during a study period of 8 yr. The study population consisted of 391 subjects who were 15 to 40 yr of age at initial examination, when they underwent spirometry and an interviewer-administered ATS-DLD-78-A questionnaire on respiratory health, and who were reexamined 8 yr later. The association between the development of symptoms and the rate of change in FEV1 over time (delta FEV1, ml/yr) was studied in a linear regression model that included the potential confounders and other determinants of the outcome. The presence of modification by such factors as smoking, childhood exposure to environmental tobacco smoke, gender, or atopy was assessed by the significance of interaction terms between potential modifiers and incident symptoms. Subjects who developed wheezing and dyspnea and in whom a doctor diagnosed asthma had a significantly greater average annual change in FEV1 compared with those without respiratory symptoms or asthma (-12.3 ml/yr, SE 5.0; -16.2 ml/yr, SE 5.5; and -42.6 ml/yr, SE 11.5, respectively). When focusing on subjects without a diagnosis of asthma, the associations with appearance of wheezing and dyspnea remained significant. The associations were in general stronger in never smokers compared with smokers and were strongest in ex-smokers. The presence of atopy was a significant modifier, so that in subjects with atopy there was a stronger negative association between the onset of cough and asthma and delta FEV1 than in those without.(ABSTRACT TRUNCATED AT 250 WORDS)

Exercise performance after lung transplantation

Heart-lung, double lung, and single lung transplantation have been shown to be effective in the treatment of patients with advanced cardiopulmonary disorders. An overlap in indications occurs for the different procedures, and in many situations the factors that are important in selecting the best operation for a given patient have not been clearly elucidated. To determine whether the anticipated exercise capacity should be an important consideration in the selection of the optimal procedure for a given patient, we compared exercise performance in patients who had undergone the different lung transplantation procedures in the preceding year and were otherwise well. Eleven heart-lung, six double lung, and 16 single lung recipients and 28 control subjects underwent maximal symptom-limited incremental exercise tests using a cycle ergometer. At peak exercise, transplant recipients reached maximum oxygen uptakes in the range of 40% to 60% of predicted values; no significant differences existed between the means of the different transplant groups. Ventilatory factors did not appear to limit exercise in any group. The exercise responses in the transplant subjects were characterized by reduced aerobic capacity and diminished oxygen pulse, factors indicating abnormal cardiovascular performance. Our data indicate that moderate levels of exercise can be anticipated early after heart-lung, double lung, and single lung transplantation. In the absence of substantial differences in exercise capacity, other considerations would appear to be more important in guiding the selection of the optimal lung replacement procedure for an individual patient.

Splenic irradiation before bone marrow transplantation for chronic myeloid leukemia: update of a prospective randomized study

Two hundred and twenty-nine patients with chronic myeloid leukaemia in chronic phase awaiting bone marrow transplantation from an HLA-identical sibling donor were randomized as part of their conditioning, to receive splenic irradiation (SI+, 115 patients), or not (SI-, 114 patients). Both groups were identical in regard to age, sex, donor/recipient sex combination and disease activity. Survival, leukaemia-free survival, incidence of transplant-related mortality, acute and chronic graft versus host disease, incidence of rejection and probability of relapse were not different in either groups at a median follow-up time of 4.5 years (minimum follow-up 2 years). Recovery of peripheral white blood cell counts to 1 x 10(9)/l but not of platelet counts to 50 x 10(9)/l was significantly faster in patients with SI+ (21 vs 24 days). This small benefit does not justify routine splenic irradiation prior to BMT, in CML.

Risk of fatal and near-fatal asthma in relation to inhaled corticosteroid use

OBJECTIVE

To examine the relationship between patterns of use of inhaled beclomethasone dipropionate and the risk of fatal and near-fatal asthma.

DESIGN

Nested case-control analysis of a historical cohort; a further analysis.

SETTING

The 12,301 residents of Saskatchewan aged 5 to 54 years who were dispensed 10 or more asthma drugs from 1978 to 1987.

PATIENTS

The 129 persons who experienced asthma death (n = 44) and near-death (n = 85) and their 655 controls matched as to age and date of entry into the cohort, with the additional matching criteria of at least one hospitalization for asthma in the prior 2 years, region of residence, and having received social assistance.

MAIN OUTCOME

Life-threatening attacks of asthma defined as death due to asthma or the occurrence of hypercarbia, intubation, and mechanical ventilation during an acute attack of asthma.

RESULTS

After accounting for the risk associated with use of other medications and adjustment for markers of risk of adverse events related to asthma, subjects who had been dispensed, on average, one or more metered-dose inhalers of beclomethasone per month over a 1-year period had a significantly lower risk of fatal and near-fatal asthma (odds ratio, 0.1; 95% confidence interval, 0.02 to 0.6).

CONCLUSION

These data support recent guidelines from several countries that recommend the use of inhaled corticosteroids in moderate and severe asthma.

Effect of negative pressure ventilation in severe chronic obstructive pulmonary disease

The hypothesis that patients with chronic obstructive pulmonary disease (COPD) have chronic inspiratory muscle fatigue was tested in an effectiveness trial in which negative pressure ventilation (NPV) was used to produce inspiratory muscle rest. In a double-blind study 184 patients with severe COPD were randomly allocated active or sham NPV treatment for a 12-week period of home use. The distance walked in a 6 min walk test was the primary outcome variable. Secondary outcome measures were cycle exercise endurance time, severity of dyspnoea, quality of life, arterial blood gas tensions, and respiratory muscle strength. The percentage reduction in amplitude of the diaphragmatic electromyographic signal multiplied by hours of NPV was used to reflect the dose of NPV so we could examine dose-response relations. Analysis was based on intention to treat. We found no evidence of a clinically or statistically significant difference in any outcome measure between active and sham groups. No dose-response relation was observed. Moreover, the intervention was poorly accepted despite substantial clinical support. We conclude that NPV as used in this study is difficult to apply and ineffective when used with the aim of resting the respiratory muscles in patients with stable COPD.

Autologous versus allogeneic bone marrow transplantation for non-Hodgkin's lymphoma: a case-controlled analysis of the European Bone Marrow Transplant Group Registry data

PURPOSE

A case-controlled study of patients who reported to the European Bone Marrow Transplant Group (EBMTG) was performed to investigate the relative roles and efficacy of allogeneic (alloBMT) and autologous bone marrow transplantation (ABMT) in non-Hodgkin's lymphoma.

PATIENTS AND METHODS

Of 1,060 patients who reported to the lymphoma registry, 938 patients underwent ABMT and 122 patients underwent alloBMT. A case-controlled study was performed by matching 101 alloBMT patients with 101 ABMT patients. The case matching was performed after the selection of the main prognostic factors for progression-free survival by a multivariate analysis.

RESULTS

The progression-free survival was similar in both types of transplants (49% alloBMT v 46% ABMT). The overall relapse and progression rate for the alloBMT patients was 23% compared with 38% in the ABMT patients. This difference was not significant statistically. In the lymphoblastic lymphoma subgroup, alloBMT was associated with a lower relapse rate than ABMT (24% alloBMT v 48% ABMT; P = .035). The progression-free survival, however, was not significantly different because patients with lymphoblastic lymphoma who underwent alloBMT had a higher procedure-related mortality (24% alloBMT v 10% ABMT; P = .06). A significantly lower relapse/progression rate was also observed in patients with chronic graft-versus-host disease (cGVHD) compared with those patients without (0% cGVHD v 35% no cGVHD; P = .02). Fourteen of 18 patients who had cGVHD also had lymphoblastic lymphoma.

CONCLUSION

This study suggests that ABMT and alloBMT for non-Hodgkin's lymphoma are comparable, with the exception of lymphoblastic lymphoma in which a graft-versus-lymphoma effect may account for the lower relapse rate for patients who underwent alloBMT.

No advantage for patients who receive splenic irradiation before bone marrow transplantation for chronic myeloid leukaemia: results of a prospective randomized study

A total of 239 patients with chronic myeloid leukaemia (CML) in chronic phase awaiting bone marrow transplantation (BMT) from an HLA-identical sibling donor were randomized to receive, as part of their conditioning, splenic irradiation (SI+) or no splenic irradiation (SI-). There was no difference between the SI+ and SI- groups regarding the distribution of age, sex, donor/recipient sex combination and blood counts at diagnosis and at BMT. Survival, leukaemia-free survival (LFS), incidence of transplant-related mortality, incidence of rejection and probability of relapse do not differ between the 117 SI+ and the 118 SI- patients at a median follow-up time of 2.5 years (minimum 0.5 years). LFS at 30 months is 56% (SE 5%) for the SI+ and 51% (SE 6%) for the SI- group (p = 0.65). LFS is better for younger patients (less than 25 years), for patients without T cell depletion and for those with a low white blood cell count at diagnosis (less than 30 x 10(9)/l) (p less than 0.05). It is worst for male recipients of a female marrow (p less than 0.05). The incidence of graft-versus-host disease grade greater than or equal to II was higher in the SI+ group, though not significantly. We conclude that routine splenic irradiation prior to BMT for patients with CML is of no benefit and should not be used as a routine procedure.

Double-lung transplantation for cystic fibrosis. The Cystic Fibrosis Transplant Study Group

One hundred twenty cystic fibrosis patients were accepted for transplantation. Twenty-five patients underwent double-lung transplantation. Twenty-five patients died awaiting transplantation (20.6%). There were 13 female and 12 male patients. Their mean age was 28 years (range, 7 to 34 years), and mean percentage ideal body weight was 76% (range, 58.5% to 91.9%). Most patients were hypoxic and hypercarbic. Two patients underwent tracheal anastomosis, 15 had en bloc bronchial anastomoses, and 8 had sequential single-lung transplants. Operative mortality was 16%; all deaths were related to bleeding from extensive adhesions. Actuarial survival at 1 year was 64%. Rejection and infection were frequent during the first month and decreased thereafter. Airway complications occurred in 5 patients but were amenable to laser therapy and stenting. We conclude that double-lung transplantation is an acceptable modality for the treatment of cystic fibrosis patients with end-stage lung disease. It may be a better alternative to heart-lung transplantation considering the paucity of thoracic organ donors.