The burden of disease due to COVID-19 in Sweden: a disability-adjusted life years (DALY) study

Background

Many countries have been severely affected by the COVID-19 pandemic, including Sweden, which has been in the spotlight regarding its policies and their impact on mortality and morbidity. Therefore, it is of high interest to measure the disease burden of COVID-19 in terms of disability-adjusted life years (DALYs). DALYs have two main components: the years of life lost through premature death (YLL) and the number of years lived with disability (YLD). This study aims to measure DALYs due to COVID-19 in Sweden.

Methods

This study used data from the nationwide multi-register observational study SCIFI-PEARL (Swedish COVID-19 Investigation for Future Insights - a Population Epidemiology Approach using Register Linkage) covering the entire Swedish population. The methodology used in the modelling and calculation of DALYs was based on the Global Burden of Disease guidelines, using Sweden-specific life tables for estimated life expectancies.

Results

In Sweden, 152877 DALYs were lost to COVID-19 between March 2020 and October 2021, corresponding to 1447/ 100 000, 99,3% of which was attributed to YLL. DALYs loss occurred mainly among elderly groups with 66,78 % of DALYs being attributed to individuals above 70 years old. 57,6% of the lost DALYs occurred among men that lost more DALYs compared to females in all age groups.

Conclusions

Similar to other countries, the burden of COVID-19 in Sweden is concentrated mainly among the elderly, which contributed to the highest DALY loss due to mortality. Yet, DALY loss remains lower for COVID-19 compared to other major non-communicable diseases such as cardiovascular diseases and neoplasms. The contribution of YLD was minimal. However, YLD due to post-Covid is not well understood and long-term disability is likely still underestimated.

Key messages

• The burden of COVID-19 was mainly due to premature mortality in the older age groups.

• More research is needed especially on post-COVID disability to derive better estimates of YLD.

Time-of-flight mass spectrometry of particle emission during irradiation with slow, highly charged ions

We describe a setup for the analysis of secondary ions and neutrals emitted from solid surfaces and two-dimensional materials during irradiation with highly charged ions. The ultrahigh vacuum setup consists of an electron beam ion source to produce bunches of ions with various charge states q (e.g., Xe¹⁺-Xe⁴⁶⁺) and thus potential energies, a deceleration/acceleration section to tune the kinetic energy of the ions in the range of 5 keV to 20 × q keV, a sample stage for laser-cleaning and positioning of freestanding as well as supported samples, a pulsed excimer laser for post-ionization of sputtered neutrals, and a reflectron type time-of-flight mass spectrometer, enabling us to analyze mass and velocity distributions of the emitted particles. With our setup, contributions from potential and kinetic energy deposition can be studied independently of each other. Charge dependent experiments conducted at a constant kinetic energy show a clear threshold for the emission of secondary ions from SrTiO₃. Data taken with the same projectile charge state, but at a different kinetic energy, reveal a difference in the ratio of emitted particles from MoS₂. In addition, first results are presented, demonstrating how velocity distributions can be measured with the new setup.

Fluoroquinolone use for uncomplicated urinary tract infections in women: a retrospective cohort study

OBJECTIVES

The United States Food & Drug Administration released an advisory in 2016 that fluoroquinolones be relegated to second-line agents for uncomplicated urinary tract infections (UTIs) given reports of rare but serious side effects; similar warnings have followed from Health Canada and the European Medicines Agency. The objective was to determine whether alternative non-fluoroquinolone agents are as effective as fluoroquinolones in the treatment of UTIs.

METHODS

We conducted a retrospective population-based cohort study using administrative health data from six Canadian provinces. We identified women (n = 1 585 997) receiving antibiotic treatment for episodes of uncomplicated UTIs (n = 2 857 243) between January 1 2005 and December 31 2015. Clinical outcomes within 30 days from the initial antibiotic dispensation were compared among patients treated with a fluoroquinolone versus non-fluoroquinolone agents. High-dimensional propensity score adjustments were used to ensure comparable treatment groups and to minimize residual confounding.

RESULTS

Fluoroquinolone use for UTI declined over the study period in five of six Canadian provinces and accounted for 22.3-48.5% of treatments overall. The pooled effect across the provinces indicated that fluoroquinolones were associated with fewer return outpatient visits (OR 0.89, 95%CI 0.87-0.92), emergency department visits (OR 0.74, 95%CI 0.61-0.89), hospitalizations (OR 0.83, 95%CI 0.77-0.88), and repeat antibiotic dispensations (OR 0.77, 95%CI 0.75-0.80) within 30 days.

CONCLUSIONS

Fluoroquinolones are associated with improved clinical outcomes among women with uncomplicated UTIs. This benefit must be weighed against the risk of fluoroquinolone resistance and rare but serious fluoroquinolone side effects when selecting first-line treatment for these patients.

Applying the Care Group model to tuberculosis control: findings from a community-based project in Mozambique

BACKGROUND

We describe the effectiveness of an innovative community-based social mobilization approach called Care Groups to improve the effectiveness of the national tuberculosis (TB) program by increasing TB testing and improving treatment outcomes in six districts of rural Mozambique.

METHODS

The Care Group approach, which was implemented in a population of 218 191, enabled a facilitator to meet every 6 months with 10-12 community health volunteers (forming a Care Group) to share key TB messages and then for them to convey these messages over the subsequent 6 months to 10-12 households. Three household surveys were performed over 5 years to measure population-level changes in knowledge and behaviors. Data from village TB, laboratory, and district registers were also used to monitor activities and outcomes.

RESULTS

There were substantial improvements in TB-related knowledge and behaviors in the number of patients initiating treatment, in the percentage of patients receiving directly observed treatment, in treatment success, and in TB-related mortality.

CONCLUSION

Care Groups are uniquely suited to address some of the challenges of TB control. This project sheds light on a new strategy for engaging communities to address not only TB, but other health priorities as well.

Lung cancer care trajectory at a Canadian centre: an evaluation of how wait times affect clinical outcomes

BACKGROUND

Lung cancer continues to be one of the most common cancers in Canada, with approximately 28,400 new cases diagnosed each year. Although timely care can contribute substantially to quality of life for patients, it remains unclear whether it also improves patient outcomes. In this work, we used a set of quality indicators that aim to describe the quality of care in lung cancer patients. We assessed adherence with existing guidelines for timeliness of lung cancer care and concordance with existing standards of treatment, and we examined the association between timeliness of care and lung cancer survival.

METHODS

Patients with lung cancer diagnosed between 2010 and 2015 were identified from the Pulmonary Division Lung Cancer Registry at our centre.

RESULTS

We demonstrated that the interdisciplinary pulmonary oncology service successfully treated most of its patients within the recommended wait times. However, there is still work to be done to decrease variation in wait time. Our results demonstrate a significant association between wait time and survival, supporting the need for clinicians to optimize the patient care trajectory.

INTERPRETATION

It would be helpful for Canadian clinicians treating patients with lung cancer to have wait time guidelines for all treatment modalities, together with standard definitions for all time intervals. Any reductions in wait times should be balanced against the need for thorough investigation before initiating treatment. We believe that our unique model of care leads to an acceleration of diagnostic steps. Avoiding any delay associated with referral to a medical oncologist for treatment could be an acceptable strategy with respect to reducing wait time.

Dipeptidyl peptidase-4 inhibitors and the risk of community-acquired pneumonia in patients with type 2 diabetes

AIMS

To determine whether the use of dipeptidyl peptidase-4 (DPP-4) inhibitors is associated with an increased risk of community-acquired pneumonia.

METHODS

The UK Clinical Practice Research Datalink and the Hospital Episodes Statistics database were used to conduct a nested case-control analysis within a cohort of new users of antidiabetic drugs between 2007 and 2012. Incident cases of hospitalization for community-acquired pneumonia were matched with up to 20 controls on age, duration of treated diabetes, calendar year and duration of follow-up. Conditional logistic regression models were used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for hospitalization for community-acquired pneumonia associated with current use of DPP-4 inhibitors compared with current use of two or more oral antidiabetic drugs.

RESULTS

The cohort included 49,653 patients, of whom 562 were hospitalized for community-acquired pneumonia during follow-up (incidence rate 5.2/1000 person-years). Compared with current use of two or more oral antidiabetic drugs, current use of DPP-4 inhibitors was not associated with an increased risk of hospitalized community-acquired pneumonia overall (adjusted OR 0.80, 95% CI 0.50-1.29) or according to duration of use (p for trend = 0.57).

CONCLUSIONS

The use of DPP-4 inhibitors was not associated with an increased risk of hospitalization for community-acquired pneumonia. Additional research is needed to assess the association between these drugs and other serious infections.

Geographical variations in the prevalence of atopic sensitization in six study sites across Canada

BACKGROUND

Geographical variations in atopic sensitization in Canada have not been described previously. This study used the standardized protocol of the European Community Respiratory Health Survey-1 (ECRHS-1) to investigate the distribution and predictors of atopic sensitization in six sites across Canada and to compare the results with some ECRHS-1 centers.

METHODS

Adults aged 20-44 years in six study sites across Canada underwent allergy skin testing using 14 allergens (Dermatophagoides pteronyssinus, Dermatophagoides farinae) cat, cockroach, grasses (Timothy grass, Kentucky grass), molds (Cladosporium herbarium, Alternaria alternata, Aspergillus fumigatus, Penicillium), trees (tree mix, birch, Olea europea), and common ragweed.

RESULTS

The overall prevalence of atopy (skin test over 0 mm to any allergen) was 62.7%. There was significant geographical variation in the prevalence of atopy in the six study sites (lowest 55.6% [95% C.I.51.3-59.9] in Prince Edward Island, highest 66.0 [61.7-70.3] in Montreal) and of sensitization to each of the allergens tested even after adjustment for confounders. When the first eight of the nine allergens in the ECRHS were used to estimate the prevalence of atopic sensitization, the prevalence of atopy in Canada was 57% compared with 35.2% overall for centers in the ECRHS. The prevalence of atopy in Vancouver (57% [52.3-61.8]) was close to that of Portland, Oregon (52.1% [46.2-58.0]).

CONCLUSION

There was a significant variation in atopic sensitization among different study sites across Canada. The prevalence of atopic sensitization is relatively high in Canada compared with sites in the ECRHS and this may, in part, account for the high prevalence of asthma and asthma symptoms in Canada.

Developmentally induced Mll1 loss reveals defects in postnatal haematopoiesis

The Mixed Lineage Leukemia (MLL) gene is disrupted by chromosomal translocations in acute leukemia, producing a fusion oncogene with altered properties relative to the wild-type gene. Murine loss-of-function studies have demonstrated an essential role for Mll in developing the haematopoietic system, yet studies using different conditional knockout models have yielded conflicting results regarding the requirement for Mll during adult steady-state haematopoiesis. Here, we employ a loxP-flanked Mll allele (Mll^F) and a developmentally-regulated, haematopoietic-specific VavCre transgene to re-assess the consequences of Mll loss in the haematopoietic lineage, without the need for inducers of Cre recombinase. We show that VavCre;Mll mutants exhibit phenotypically normal fetal haematopoiesis, but rarely survive past 3 weeks of age. Surviving animals are anemic, thrombocytopenic and exhibit a significant reduction in bone marrow haematopoietic stem/progenitor populations, consistent with our previous findings using the inducible Mx1Cre transgene. Furthermore, the analysis of VavCre mutants revealed additional defects in B-lymphopoiesis that could not be assessed using Mx1Cre-mediated Mll deletion. Collectively, these data support the conclusion that Mll plays an essential role in sustaining postnatal haematopoiesis.

Latamoxef versus carbenicillin plus gentamicin or carbenicillin plus mecillinam in leukopenic, febrile patients with solid tumors

Sixty-six febrile episodes associated with leukopenia were observed in 56 patients with solid tumors, WBC less than 1.5 X 10(9)/l and temperature greater than or equal to 38.5 degrees C. Stratification to antibiotic treatment regimen was made with regard to prior cis-dichlorodiamineplatinum (cis-platinum) treatment or not. Patients who had received no cis-platinum were randomized between carbenicillin 10 g every 8 h plus gentamicin 80 mg every 8 h or latamoxef 2 g every 8 h (group I). Patients having received cis-platinum were treated with carbenicillin 10 g every 8 h plus mecillinam 800 mg every 8 h or latamoxef 2 g every 8 h (group II). The first dose of latamoxef was preceded by 10 mg of vitamin K i.v. In group I, clinical response was observed in 10 of 19 febrile episodes (52.6%) treated with carbenicillin plus gentamicin and in 10 of 14 (71.4%) treated with latamoxef (p greater than 0.05). In group II, 6 of 14 febrile episodes treated with carbenicillin plus mecillinam responded (42.9%) while 11 of 19 (57.9%) responded to latamoxef (p greater than 0.05). No bleeding due to antibiotic treatment was observed. No statistical difference between standard antibiotic therapy and latamoxef was seen in this subset of patients.

Thrombotic thrombocytopenic purpura: treatment with a combination of antiplatelet drugs

Thrombotic thrombocytopenic purpura (TTP) is a rare disease with a vary high mortality. Different modalities of therapy have been tried, but often with no effect. Recently, interest has focused on drugs interfering with platelet function, though few patients have received antiplatelet drugs as the only therapy. We describe a patient with TTP, who recovered completely on a combination therapy with dextran, aspirin and dipyridamole.

ProtSweep, 2Dsweep and DomainSweep: protein analysis suite at DKFZ

The wealth of transcript information that has been made publicly available in recent years has led to large pools of individual web sites offering access to bioinformatics software. However, finding out which services exist, what they can or cannot do, how to use them and how to feed results from one service to the next one in the right format can be very time and resource consuming, especially for non-experts. Automating this task, we present a suite of protein annotation pipelines (tasks) developed at the German Cancer Research Centre (DKFZ) oriented to protein annotation by homology (ProtSweep), by domain analysis (DomainSweep), and by secondary structure elements (2Dsweep). The aim of these tasks is to perform an exhaustive structural and functional analysis employing a wide variety of methods in combination with the most updated public databases. The three servers are available for academic users at the HUSAR open server http://genius.embnet.dkfz-heidelberg.de/menu/biounit/open-husar/

Differences in proteoglycan deposition in the airways of moderate and severe asthmatics

Excess deposition of proteoglycans (PGs) has been described in the subepithelial layer of the asthmatic airway wall. However, less is known about deposition in the airway smooth muscle (ASM) layer, and whether the pattern of deposition is altered depending upon disease severity. Endobronchial biopsies were performed in patients with severe or moderate asthma (defined using American Thoracic Society criteria) and in control subjects. Biopsies were immunostained for the PGs biglycan, lumican, versican and decorin. PG deposition was measured in the subepithelial and ASM layers, the former by calculating the area of positive staining, and the latter by determining the percentage area stained using point counting. Immunostaining for PGs was prominent in biopsies from both moderate and severe asthmatics, compared with control subjects. While there was no difference in the amount of PG in the subepithelial layer between the two asthmatic groups, the percentage area of biglycan and lumican staining in the ASM layer was significantly greater in moderate versus severe asthmatics. Differences in the deposition of proteoglycans within the airway smooth muscle layer of moderate versus severe asthmatics potentially impact on the functional behaviour of the airway smooth muscle in these two groups of patients.

Ultracold heteronuclear molecules in a 3D optical lattice

We report on the creation of ultracold heteronuclear molecules assembled from fermionic 40K and bosonic 87Rb atoms in a 3D optical lattice. Molecules are produced at a heteronuclear Feshbach resonance on both the attractive and the repulsive sides of the resonance. We precisely determine the binding energy of the heteronuclear molecules from rf spectroscopy across the Feshbach resonance. We characterize the lifetime of the molecular sample as a function of magnetic field and measure lifetimes between 20 and 120 ms. The efficiency of molecule creation via rf association is measured and is found to decrease as expected for more deeply bound molecules.

Placental expression of glycophosphatidylinositol (GPI)-anchored proteins in paroxysmal nocturnal haemoglobinuria

Paroxysmal nocturnal haemoglobinuria (PNH) is a clonal stem cell disorder in which a defect of glycophosphatidylinositol (GPI)-anchored proteins leads to higher morbidity and mortality because of intravascular haemolysis, haemoglobinuria, pancytopenia and an increased frequency of thrombotic events. We report here the clinical features of a pregnant woman with PNH and present an immunhistochemical analysis of complement regulators, leukocyte activation markers and placental alkaline phosphatase (PALP) on syncytiotrophoblasts and inflammatory cells in her placenta. Placental tissue from normal deliveries served as controls. The patient had severe PNH with haemolysis, thrombosis episodes and signs of bone marrow failure. Placental syncytiotrophoblasts and villous cells of fetal origin in both normal placentas and the placenta from the PNH patient expressed PALP and the complement regulators CD46, CD55 and CD59. Additionally, CD11b-positive leukocytes of presumed maternal origin were negative for CD15 in the PNH placenta, while they stained positive within the villous space and in normal placentas. These findings show that fetally derived cells in the PNH placenta expressed GPI-linked molecules that are known to be of importance for a successful pregnancy outcome.

Localization of bosonic atoms by fermionic impurities in a three-dimensional optical lattice

We observe a localized phase of ultracold bosonic quantum gases in a 3-dimensional optical lattice induced by a small contribution of fermionic atoms acting as impurities in a Fermi-Bose quantum gas mixture. In particular, we study the dependence of this transition on the fermionic (40)K impurity concentration by a comparison to the corresponding superfluid to Mott-insulator transition in a pure bosonic (87)Rb gas and find a significant shift in the transition parameter. The observed shift is larger than expected based on a simple mean-field argument, which indicates that disorder-related effects play a significant role.

Low-dose inhaled and nasal corticosteroid use and the risk of cataracts

Orally inhaled corticosteroid use has been convincingly linked to an increase in the risk of cataracts, although the risk at lower doses in common use remains uncertain. The potential risk of cataracts with the use of nasal corticosteroids is unknown. A matched nested case-control analysis was performed in a population-based cohort of elderly people who had been dispensed medications for airway disease, as identified through a universal drug benefit plan. Inhaled corticosteroid use was associated with a dose-related increase in both the risk of all cataracts and severe cataracts requiring extraction, and the increase in risk of severe cataracts was apparent even at daily doses of </=500 microg. An excess risk with nasal corticosteroids was not apparent for severe cataracts. It is concluded that, among the elderly, even low doses of inhaled corticosteroids are associated with a small but significant excess risk of cataracts requiring extraction. Such an excess risk was not observed with nasal corticosteroids.

Cost of autologous peripheral blood stem cell transplantation: the Norwegian experience from a multicenter cost study

High-dose therapy with autologous blood progenitor cell support is now routinely used for patients with certain malignant lymphomas and multiple myeloma. We performed a prospective cost analysis of the mobilization, harvesting and cryopreservation phases and the high-dose therapy with stem cell reinfusion and hospitalization phases. In total, 40 consecutive patients were studied at four different university hospitals between 1999 and 2001. Data on direct costs were obtained on a daily basis. Data on indirect costs were allocated to the specific patient based on estimates of relevant department costs (ie the service department's costs), and by means of predefined allocation keys. All cost data were calculated at 2001 prices. The mean total costs for the two phases were US$ 32,160 (range US$ 19,092-50,550). The mean total length of hospital stay for two phases was 31 days (range 27-37). A large part of the actual cost in the harvest phase was attributed to stem cell mobilization, including growth factors, harvesting and cryopreservation. In the high-dose chemotherapy phase, the most significant part of the costs was nursing staff. Average total costs were considerably higher than actual DRG-based reimbursement from the government, indicating that the treatment of these patients was heavily subsidized by the basic hospital grants.

Low-dose inhaled corticosteroids and the risk of acute myocardial infarction in COPD

Inflammation plays a major role in the development and complications of atherosclerosis. Here, the dose-related impact of inhaled corticosteroids (ICS), used for their anti-inflammatory properties, on the risk of acute myocardial infarction (AMI) is studied in a cohort of chronic obstructive pulmonary disease (COPD) patients. Saskatchewan (Canada) health services databases were used to form a population-based cohort of 5,648 patients, > or =55 yrs, who received a first treatment for COPD between 1990 and 1997. A nested case-control analysis was conducted, where 371 cases presenting with a first AMI were matched with 1,864 controls, based on the date of cohort entry and age. A conditional logistic regression was used to estimate the effect of ICS, after adjusting for use of oral corticosteroids, severity of COPD, sex, systemic hypertension, diabetes and cardiovascular disease. ICS were used in the prior year by 42.2% of cases and 46.4% of controls. Overall, current use of ICS was not associated with a significant decrease in the risk of AMI. However, a 32% reduction in the risk of AMI was observed for doses ranging 50-200 microg x day(-1). In conclusion, very low doses of inhaled corticosteroids may be associated with a reduction in the risk of acute myocardial infarction.

Inhaled corticosteroids and the risk of a first exacerbation in COPD patients

The role of inhaled corticosteroids (ICS) in asthma is well established, but their benefit in the management of chronic obstructive pulmonary disease (COPD) is still controversial. The current study assessed whether ICS are effective in preventing a first exacerbation of COPD. A cohort of newly treated COPD patients was formed from the Administrative Databases of Saskatchewan Health. The outcome was the occurrence of a first moderate or severe exacerbation from 1990-1999. Moderate exacerbations involved prescriptions for an antibiotic and an oral corticosteroid on the same day. Severe exacerbations were hospitalisations with a primary discharge diagnosis of COPD. A nested case-control design was used and matched on year of birth and cohort entry. Rate ratios (RR) were further adjusted for use of other medication and other confounders. There were 995 exacerbations among 4,455 subjects. The rate of a first exacerbation was increased with any use of ICS in the year prior to the index date (RR: 1.27; 95% CI: 1.08-1.48) and with current use (RR: 1.51; 95% CI: 1.22-1.87), and it increased with increasing daily doses of ICS. Inhaled corticosteroids do not seem to be beneficial in reducing the risk of a first exacerbation of chronic obstructive pulmonary disease.

The Helmholtz Network for Bioinformatics: an integrative web portal for bioinformatics resources

SUMMARY

The Helmholtz Network for Bioinformatics (HNB) is a joint venture of eleven German bioinformatics research groups that offers convenient access to numerous bioinformatics resources through a single web portal. The 'Guided Solution Finder' which is available through the HNB portal helps users to locate the appropriate resources to answer their queries by employing a detailed, tree-like questionnaire. Furthermore, automated complex tool cascades ('tasks'), involving resources located on different servers, have been implemented, allowing users to perform comprehensive data analyses without the requirement of further manual intervention for data transfer and re-formatting. Currently, automated cascades for the analysis of regulatory DNA segments as well as for the prediction of protein functional properties are provided.

AVAILABILITY

The HNB portal is available at http://www.hnbioinfo.de

Inhaled corticosteroids and hospitalisation due to exacerbation of COPD

Previous studies have provided conflicting evidence as to the possible benefits of inhaled corticosteroids in the treatment of chronic obstructive pulmonary disease (COPD). Using the Saskatchewan healthcare databases subjects were identified who were aged > or = 55 yrs, initiating regular treatment for COPD but without any prior treatment for asthma. In the current nested case-control analysis, the authors concentrated on 1,742 subjects with a first hospitalisation for COPD after January 1, 1990 and examined whether the use of inhaled corticosteroids was associated with a change in the risk of a subsequent hospitalisation for COPD. The cases consisted of 846 patients with a subsequent hospitalisation for COPD. These were matched on age, time since the prior hospitalisation and use of other respiratory therapy to all possible person moments in the cohort without rehospitalisation. After further adjustment for comorbidity, sex, calendar year and intensity of other drug therapy, inhaled corticosteroids were not significantly associated with risk of a subsequent COPD hospitalisation. Even relatively high doses of inhaled corticosteroids, >800 microg of beclomethasone or the equivalent per day, were not associated with the risk of COPD hospitalisation. No reduction in chronic obstructive pulmonary disease exacerbations requiring hospitalisation, in relation to the use of inhaled corticosteroids, were observed.

Inhaled short acting beta agonist use in COPD and the risk of acute myocardial infarction

BACKGROUND

A recent study found that short acting beta agonists used in the treatment of asthma and chronic obstructive pulmonary disease (COPD) may increase the risk of acute myocardial infarction. We investigated this hypothesis in patients with COPD already at high risk of cardiac disease.

METHODS

The Saskatchewan Health Services databases were used to form a population based cohort of all patients newly diagnosed with COPD over the age of 55 years identified between 1980 and 1997. All subjects were followed up until 1999, death, or the first occurrence of acute myocardial infarction. Those with a first acute myocardial infarction, fatal or non-fatal, were matched on calendar time and age with cohort members.

RESULTS

The cohort consisted of 12 090 subjects including 1127 cases with fatal or non-fatal acute myocardial infarction. The adjusted rate ratio for current use of inhaled beta agonists was 1.12 (95% confidence interval (CI) 0.95 to 1.33), and for first time use it was 1.02 (95% CI 0.52 to 2.00). There was also no significant increase in risk when the analysis was restricted to subjects with cardiac risk factors such as hypertension and diabetes, or to subjects not having been prescribed beta blocker medications.

CONCLUSION

Short acting inhaled beta agonist use among patients with COPD does not appear to increase the risk of fatal or non-fatal acute myocardial infarction.

Use of anti-inflammatory therapy and asthma mortality in Japan

Asthma treatment guidelines were introduced in Japan in the 1990s, insisting as elsewhere, on the importance of anti-inflammatory therapy. The present study assessed whether use of anti-inflammatory medications was associated with a decrease in asthma mortality in Japan, the first country to use leukotriene receptor antagonists. A population-based ecological study was conducted, spanning the period 1987-1999, among people aged 5-34 yrs in Japan. The association between the yearly rate of asthma death and sales of inhaled corticosteroids and leukotriene receptor antagonists was estimated using Poisson regression. The yearly asthma death rate was stable at 6-7 deaths per million before the introduction of leukotriene receptor antagonists in 1995 and decreased by 23% thereafter, reaching 3.5 per million in 1999. The rate of asthma death was found to decrease with increasing use of both leukotriene receptor antagonists and inhaled corticosteroids. The rate ratio of asthma death was 0.96 per 1 million 25-day treatment courses of inhaled corticosteroids and 0.80 for every 1 million 25-day treatment courses of leukotriene receptor antagonists, consumed per year in Japan. The increasing use of inhaled corticosteroids and leukotriene receptor antagonists may have contributed to the significant reduction in asthma mortality among young asthmatics in Japan.

Regular use of inhaled corticosteroids and the long term prevention of hospitalisation for asthma

BACKGROUND

Inhaled corticosteroids are effective at preventing asthma morbidity and mortality. Most studies, however, have focused on short term effects, raising uncertainty about their effectiveness in the long term.

METHODS

The Saskatchewan Health databases were used to form two population based cohorts of asthma patients aged 5-44 between 1975 and 1991. The first cohort included all subjects from the start of asthma treatment, while the second included subjects hospitalised for asthma from the date of discharge. Subjects were followed up, starting 1 year after cohort entry and continuing until 1997, 54 years of age, or death. The outcome was the first asthma hospital admission and readmission, respectively, to occur during follow up. A nested case-control design was used by which all cases were matched on calendar time and several markers of asthma severity to all available controls within the cohort.

RESULTS

The full cohort included 30 569 asthmatic subjects of which 3894 were admitted to hospital for asthma and 1886 were readmitted. The overall rate of asthma hospitalisation was 42.4 per 1000 asthma patients per year. Regular use of inhaled corticosteroids was associated with reductions of 31% in the rate of hospital admissions for asthma (95% confidence interval (CI) 17 to 43) and 39% in the rate of readmission (95% CI 25 to 50). The rate reduction found during the first 4 years of follow up was sustained over the longer term. Regular use of inhaled corticosteroids can potentially prevent between five hospital admissions and 27 readmissions per 1000 asthma patients per year.

CONCLUSION

Regular use of low dose inhaled corticosteroids prevents a large proportion of hospital admissions with asthma, both early and later on in the course of the disease.

Risk factors for bronchial hyperresponsiveness in late childhood and early adolescence

The prevalence of asthma and bronchial hyperresponsiveness (BHR) tends to decrease in male children but increase in female children in the transition from childhood to adolescence. Hormonal factors may be involved in the natural history of asthma during this period. In a prospective study of Montreal school children, the authors examined the determinants of BHR according to the child's pubertal status; 156 male children and 168 female children without a prior diagnosis of asthma were followed for an average of 4.6 yrs. Average age at follow-up was 13.4 yrs and 59% had reached puberty. The prevalence of BHR at follow-up was similar among pre- and postpubertal male children (25.0% versus 29.2%),while BHR was more common among post- compared with prepubertal female children (33.1% versus 14.2%). There were no differences in the determinants (measured in childhood) of BHR at follow-up according to pubertal status. The major determinant of BHR was a positive skin test to dust-mite antigen. BHR was also linked to exposure to gas cooking and the presence of exercise-induced bronchospasm. In conclusion, the results of this study do not support a change in asthma phenotype with the onset of puberty. Pre- and postpuberty, the major determinant of bronchial hyperresponsiveness was skin sensitivity to mite allergen.

Persistent asthma: disease control, resource utilisation and direct costs

Despite evidence that adverse outcomes are less frequent when asthma management is optimised, the link between the level of control, disease severity and medical resource utilisation (MRU) is poorly documented. This relationship was investigated in a group of patients suffering from persistent asthma (Global Initiative for Asthma (GINA) > or = 2) in France. In 1998 a computerised family practice database was used to identify asthma patients aged 17-50 yrs. Information from the database was complemented by a patient survey to retrospectively assess the level of asthma control and hospital contacts. Costs of MRU over a 12-month study period were related to demographics, medical history, asthma control, and doses of inhaled corticosteroids prescribed during the prestudy period. A review of the computerised medical database identified 1,038 adult patients with persistent asthma, who completed the survey questionnaire. Over a 12-month period, the mean cost of MRU was 549.8 euros for well-controlled patients, 746.3 euros per patient with moderate control, and 1,451.3 euros per patient with poor control. Costs also increased significantly with age, access to free asthma care, comorbid conditions, asthma symptoms in the past year and whether inhaled corticosteroids had been prescribed before the study period. In patients with persistent asthma, large differences were observed in the use of medical resources according to control and severity. Therefore, if patients appropriately use prescribed control therapy, their use of medical resources may be reduced.

Level of control and hospital contacts in persistent asthma

The purpose of this study was to estimate relationships between asthma control and hospital contacts (visits to emergency rooms and hospitalizations) in a group of patients suffering from persistent asthma, after adjustment for prior use of inhaled corticosteroids. A computerized family practice database was used to identify patients (aged 6-50 years) with persistent asthma who received asthma therapy from January 1995. The database provided information on patient demographics and drug therapy. Asthma control was estimated by a survey of patients at the end of a 12-month study period. Frequency of hospital contacts during the study period was related to demographics, asthma control, and prescribed doses of inhaled corticosteroids during a prestudy period. Review of computerized medical files of 497 family practice physicians identified 1,966 patients with persistent asthma who met the study criteria. Of these patients, 1,251 completed the survey (63.6%). Asthma control was assessed in 1,130 patients; it was moderate or poor in 42% of the cases. During the 12-month study period, 14.8% of patients reported at least one hospital contact. The level of asthma control was significantly (p < 0.001) associated with hospital contacts. The odds ratio (OR) for hospital contact for good and poor asthma control was 0.5 (95% confidence interval [CI] 0.2-0.7) and 2.2 (95% CI 1.2-4.4), respectively. Asthma control was related to hospital contacts independently of use of inhaled corticosteroids before the study period. Overall, control of asthma was not optimal in this population. The occurrence of hospital contacts was closely related with the level of control. This association was independent of the dose of inhaled corticosteroids prescribed before the study, suggesting that in asthma, hospital contacts are primarily related to the level of control experienced by the patients.

Expression of cathepsins B, L, S, and D by gastric epithelial cells implicates them as antigen presenting cells in local immune responses

Helicobacter pylori infection is linked to chronic gastritis, peptic ulcer and gastric carcinoma. During H. pylori infection, class II MHC expression by the gastric epithelium increases, as does the number of local CD4(+) T cells, which appear to be important in the associated pathogenesis. These observations suggested that the epithelium might present antigens to T cells. Thus, we sought to determine whether gastric epithelial cells process antigens to establish their function as local antigen presenting cells (APC). We examined a panel of gastric epithelial cell lines for expression of the antigen processing cathepsins B (CB), L (CL), S (CS), and D (CD). The mRNA for these enzymes were detected by RT-PCR and the enzymes in the gastric epithelial cells were identified by various independent methods. We corroborated the expression of CB and CD on gastric epithelial cells from human biopsy samples. The functions of these proteases were confirmed by assessing their ability to digest ovalbumin, a conventional dietary antigen, and proteins from H. pylori. In summary, multiple lines of evidence suggest gastric epithelial cells process antigens for presentation to CD4(+) T cells. To our knowledge, these are the first studies to document the antigen processing capacity of human gastric epithelial cells.

Therapy-related acute lymphoblastic leukaemia with MLL rearrangements following DNA topoisomerase II inhibitors, an increasing problem: report on two new cases and review of the literature since 1992

A highly increased risk of myelodysplasia (MDS) and acute myeloid leukaemia (AML) is well established in patients previously treated for other malignancies with alkylating agents or topoisomerase II inhibitors. More recently, single cases of acute lymphoblastic leukaemia (ALL), often presenting balanced translocations involving chromosome band 11q23, have been observed. We present two such cases with t(4;11)(q21;q23), one of whom had previously received only single-agent chemotherapy with 4-epi-doxorubicin. A review of the literature since 1992 including these two patients reveals a total of 23 cases of ALL or lymphoblastic lymphoma after chemotherapy presenting balanced translocations to 11q23. All 23 patients had previously received at least one topoisomerase II inhibitor, and in two patients 4-epi-doxorubicin had been administered as single-agent chemotherapy for breast cancer. The latency period to development of t-ALL was 24 months or less in 20 out of 22 cases. The MLL gene was found to be rearranged in 14 out of 14 cases, and in three out of six cases the breakpoint was at the telomeric part of the gene, as observed in most cases of AML following therapy with topoisomerase II inhibitors. These results indicate that patients with ALL and balanced translocations to chromosome band 11q23 following chemotherapy with topoisomerase II inhibitors in the future should be included with cases of MDS or AML in calculations of risk of leukaemia.