Death from airways obstruction: accuracy of certification in Northern Ireland

Forecasts of COPD mortality in Australia: 2006-2025

BACKGROUND

Chronic Obstructive Pulmonary Disease (COPD) is currently the fifth leading cause of death in Australia, and there are marked differences in mortality trends between men and women. In this study, we have sought to model and forecast age related changes in COPD mortality over time for men and women separately over the period 2006-2025.

METHODS

Annual COPD death rates in Australia from 1922 to 2005 for age groups (50-54, 55-59, 60-64, 65-69, 70-74, 75-79, 80-84, 85+) were used. Functional time series models of age-specific COPD mortality rates for men and women were used, and forecasts of mortality rates were modelled separately for men and women.

RESULTS

Functional time series models with four basis functions were fitted to each population separately. Twenty-year forecasts were computed, and indicated an overall decline. This decline may be slower for women than for men. By age, we expect similar rates of decline in men over time. In contrast, for women, forecasts for the age group 75-79 years suggest less of a decline over time compared to younger age groups.

CONCLUSIONS

By using a new method to predict age-specific trends in COPD mortality over time, this study provides important insights into at-risk age groups for men and women separately, which has implications for policy and program development.

[Causes of mortality in COPD]

Chronic obstructive pulmonary disease (COPD) is one of the main causes of death in Spain and elsewhere in the world, with an estimated 18,000 and 2.75 million deaths annually. Mortality is predicted to increase in the next few years due to smoking and the aging population. Multiple studies confirm that COPD is underreported as a cause of death on death certificates, due to the difficulty of determining the final cause of death in these patients. The main causes of mortality in COPD range from lung cancer and cardiovascular disease in patients with mild COPD to respiratory failure in the most advanced stages. Fortunately, in the latest updates, guidelines for the management and treatment of the disease identify reduction of mortality as one of the main clinical objectives to be achieved in these patients.

Accuracy of death certificates in COPD: analysis from the TORCH trial

The Towards a Revolution in COPD Health (TORCH) trial was an international clinical trial of chronic obstructive pulmonary disease (COPD) patients where cause of death was assigned by an independent committee. Comparison of death certificate data and adjudicated cause of death allows a unique opportunity to determine death certificate accuracy and frequency of COPD listing on death certificates of COPD patients. In this analysis, the authors determine the concordance between adjudicated cause of death and primary and secondary cause of death from death certificates. In 317 (80%) of informative deaths, the primary or secondary cause of death from certificates agreed with adjudicated cause of death. Only 229 (58%) of death certificates in these COPD patients listed COPD on the certificate. COPD was not listed on the death certificate in 21% of deaths adjudicated to be caused by COPD exacerbation. Compared with pulmonary causes, the listing of COPD on certificates occurred with less frequency than cardiovascular, cancer and other categories of death. The combined primary and secondary listing on death certificates has good concordance with actual cause of death. COPD is under-reported on death certificates, and this under-reporting is more frequent when the primary cause of death is not pulmonary.

Associations between mortality, asthma, and health-related quality of life in an elderly cohort of Swedes

BACKGROUND

Asthma is a common chronic health condition among the elderly and an important cause of morbidity and mortality. Some studies show that subjective assessments of health-related quality of life (HRQL) are important predictors of mortality and survival. The primary aim of this study was to investigate whether low HRQL was a predictor of mortality in elderly subjects and whether such an association differed between subjects with and without asthma.

METHODS

In 1990, a cohort in middle Sweden was investigated using a respiratory questionnaire. To assess HRQL, the generic instrument Gothenburg Quality of Life (GQL) was used. The participants were also investigated by spirometry and allergy testing. The present study was limited to the subjects in the oldest age group, aged 60-69 years in 1990, and included 222 subjects with clinically verified asthma, 148 subjects with respiratory symptoms but no asthma or other lung diseases, and 102 subjects with no respiratory symptoms. Mortality in the cohort was followed during 1990-2008.

RESULTS

Altogether, 166 of the 472 subjects in the original cohort had died during the follow-up period of 1990-2008. Mortality was significantly higher in men, in older subjects, in smokers, and subjects with a low forced expiratory volume in one second (FEV(1)). There was, however, no difference in mortality between the asthmatic and the nonasthmatic groups. A higher symptoms score for GQL was significantly related to increased mortality. No association between HRQL and mortality was found when limiting the analysis to the asthmatic group, although the asthmatics had a lower symptom score for GQL compared to the other groups.

CONCLUSION

A higher symptom score in the GQL instrument was significantly related to increased mortality, but this association was not found when analyzing the asthmatic group alone. The negative prognostic implications of a low HRQL in the whole group and the fact that the asthmatic group had a lower HRQL than the other group supports the use of HRQL instruments in clinical health assessments.

Geographic variations in risk: adjusting for unmeasured confounders through joint modeling of multiple diseases

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is an important cause of mortality with marked geographic variations in Great Britain. Additional factors beyond cigarette smoking are likely to influence these variations, but direct information on smoking by area is not readily available. We compared methods of jointly modeling the spatial distribution of mortality from COPD and lung cancer, using the latter as a proxy for smoking, to identify areas in which risk factors other than smoking may be important.

METHODS

We obtained district-level mortality and population data for men aged 45 years or older in 1981-1999 in Great Britain. Three models were compared: Bayesian ecological regression using observed (model 1) or spatially smoothed (model 2) lung cancer standardized mortality ratio (SMR) as a smoking proxy, and bivariate regression (model 3) treating smoking as a spatial latent variable common to both diseases.

RESULTS

Model selection criteria favored models 2 and 3 over model 1. Between 9% (model 3) and 25% (model 2) of spatial variation in COPD mortality was estimated to be unrelated to smoking. After adjustment for lung cancer as a proxy for smoking, both models showed similar geographic patterns of higher COPD mortality in conurbation and mining areas, historically associated with heavy industry and higher air pollution levels.

CONCLUSIONS

Joint modeling of multiple diseases can be used to investigate geographic variations in risk. These models reveal patterns that are adjusted for the effects of shared area-level risk factors for which no direct data are available.

Risk factors for death in adults with severe asthma

BACKGROUND

Mortality risk in adult asthma is poorly understood, especially the interplay among race, disease severity, and health care access.

OBJECTIVE

To examine mortality risk factors in adult asthma.

METHODS

In a prospective cohort study of 865 adults with severe asthma in a closed-panel managed care organization, we used structured interviews to evaluate baseline sociodemographics, asthma history, and health status. Patients were followed up until death or the end of the study (mean, 2 years). We used Cox proportional hazards regression to evaluate the impact of sociodemographics, cigarette smoking, and validated measures of perceived asthma control, physical health status, and severity of asthma on the risk of death.

RESULTS

We confirmed 123 deaths (mortality rate, 6.7 per 100 person-years). In an analysis adjusted for sociodemographics and tobacco history, higher severity-of-asthma scores (hazard ratio [HR], 1.11 per 0.5-SD increase in severity-of-asthma score; 95% confidence interval [CI], 1.01-1.23) and lower perceived asthma control scores (HR, 0.91 per 0.5-SD increase in perceived asthma control score; 95% CI, 0.83-0.99) were each associated with risk of all-cause mortality. In the same adjusted analysis, African American race was not associated with increased mortality risk relative to white race (HR, 0.64; 95% CI, 0.36-1.14).

CONCLUSIONS

In a large managed care organization in which access to care is unlikely to vary widely, greater severity-of-asthma scores and poorer perceived asthma control scores are each associated with increased mortality risk in adults with severe asthma, but African American patients are not at increased risk for death relative to white patients.

A genealogical assessment of heritable predisposition to asthma mortality

RATIONALE

Asthma is a multifactorial disease; genetic factors have been suggested but have not been well defined.

OBJECTIVES

This study examined evidence for a heritable component to asthma mortality using a unique data resource consisting of Utah death certificates linked to a genealogy of Utah.

METHODS

Cases were defined as individuals whose death certificate listed asthma as a cause of death in a registry of all Utah deaths since 1904 (n = 1,553). The genealogical index of familiality analysis was used to compare the average relatedness of asthma deaths to the expected relatedness in the Utah population. Relative risks for asthma death in relatives of individuals who died of asthma are provided for close and distant relatives.

MEASUREMENTS AND MAIN RESULTS

The genealogical index of familiality identified a significantly higher average relatedness in cases (P < 0.001), even when close relationships were ignored. In addition, a significantly increased risk of dying of asthma was observed in first-degree relatives of cases (relative risk = 1.69, P < 0.001) and in second-degree relatives of cases (relative risk = 1.34, P = 0.003).

CONCLUSIONS

These results support a heritable contribution to asthma mortality.

Overcoming gaps in the management of asthma in older patients: new insights

Asthma is under-recognised and undertreated in older populations. This is not surprising, given that one-third of older people experience significant breathlessness. The differential diagnosis commonly includes asthma, chronic obstructive pulmonary disease (COPD), heart failure, malignancy, aspiration and infections. Because symptoms and signs of several cardiorespiratory diseases are nonspecific in older people and diseases commonly co-exist, investigations are important. A simple strategy for the investigation of breathlessness in older people should include a full blood count, chest radiograph, ECG, peak flow diary and/or spirometry with reversibility as a minimum. If there are major abnormalities on the ECG, an echocardiogram should also be performed. Diurnal variability in peak flow readings >or=20% or >or=15% reversibility in forced expiratory volume in 1 second, spontaneously or with treatment, support a diagnosis of asthma. Distinguishing asthma from COPD is important to allow appropriate management of disease based on aetiology, accurate prediction of treatment response, correct prognosis and appropriate management of the chest condition and co-morbidities. The two conditions are usually readily differentiated by clinical features, particularly age at onset, variability of symptoms and nocturnal symptoms in asthma, supported by the results of reversibility testing. Full lung function tests may not necessarily help in differentiating the two entities, although gas transfer factor is characteristically reduced in COPD and usually normal or high in asthma. Methacholine challenge tests previously mainly used in research are now also used widely and safely to confirm asthma in clinical settings. Interest in exhaled nitric oxide as a biomarker of airways inflammation is increasing as a noninvasive tool in the diagnosis and monitoring of asthma. Regular inhaled corticosteroids (ICS) are the mainstay of treatment of asthma. Even in mild disease in older adults, regular preventive treatment should be considered, given the poor perception of bronchoconstriction by older asthmatic patients. If symptoms persist despite ICS, addition of long-acting beta(2)-adrenoceptor agonists (LABA) should be considered. Addition of LABA to ICS improves asthma control and allows reduction in ICS dose. However, older people have been grossly under-represented in trials of LABA, many trials having excluded those >or=65 years of age. On meta-analysis, beta(2)-adrenoceptor agonists (both short acting and long acting) are associated with increased cardiovascular mortality and morbidity in asthma and COPD. While the evidence for excess cardiovascular mortality is stronger for short-acting beta(2)-adrenoceptor agonists, it would be prudent to exercise particular care in using beta(2)-adrenoceptor agonists (long acting and short acting) in those at risk of adverse cardiovascular outcomes, including older people. Regular review of cardiovascular status (and monitoring of serum potassium concentration) in patients taking beta(2)-adrenoceptor agonists is crucial. The response to LABA should be carefully monitored and alternative 'add-on' therapy such as leukotriene receptor antagonists (LRA) should be considered. LRA have fewer adverse effects and in individual cases may be more effective and appropriate than LABA. Long-term trials evaluating beta(2)-adrenoceptor agonists and other bronchodilator strategies are needed particularly in the elderly and in patients with cardiovascular co-morbidities. There is no evidence that addition of anticholinergics improves control of asthma further, although the role of long-acting anticholinergics in the prevention of disease progression is currently being researched. Older patients need to be taught good inhaler technique to improve delivery of medications to lungs, minimise adverse effects and reduce the need for oral corticosteroids. Nurse-led education programmes that include a written asthma self-management plan have the potential to improve outcomes.

Changing the burden of COPD mortality

COPD is a major cause of mortality and morbidity worldwide with an estimated 2.75 million deaths in 2000 (fourth leading cause of death). In addition to the considerable morbidity and mortality associated with COPD, this disease incurs significant healthcare and societal costs. Current COPD guidelines acknowledge that the following can improve COPD mortality: smoking cessation; long-term oxygen therapy; and lung volume reduction surgery in small subsets of COPD patients. To date, no randomized controlled trials have demonstrated an effect of pharmacological treatment on mortality, although several observational studies suggest that both long-acting bronchodilators and inhaled corticosteroids may provide a survival benefit. The possibility that these treatments reduce mortality is being investigated in ongoing large-scale clinical trials.

Asthma deaths; persistent and preventable mortality

Bronchial asthma remains a significant cause of mortality at all ages, despite the increased understanding of its pathogenesis and the range of drugs available for its treatment. Changes in therapeutic management can influence death rates and constant surveillance, combined with high-quality post mortem investigations, is essential. Disease severity, poor disease management and adverse psychosocial circumstances are all risk factors for asthma mortality. Bronchial asthma causes characteristic histological changes in the mucosa of the airways which are present even before the clinical diagnosis of asthma can be made. These include fibrous thickening of the lamina reticularis of the epithelial basement membrane, smooth muscle hypertrophy and hyperplasia, increased mucosal vascularity and an eosinophil-rich inflammatory cell infiltrate. In addition, mucoid plugging of the airway lumen is frequently associated with fatal asthma. The recognition of these changes can allow the diagnosis of asthma to be made for the first time at autopsy, in those cases where asthma goes undiagnosed in life. Acute severe asthma may be accompanied by pneumothorax and surgical emphysema of the mediastinum. Disorders which may mimic asthma include pulmonary embolism, chronic obstructive pulmonary disease and anaphylaxis, but careful post mortem examination and appropriate investigations should reveal the true cause of death.

Undiagnosed airflow obstruction: prevalence and implications

Conditions associated with airflow obstruction are often over- and underdiagnosed. Prevalence estimates of undiagnosed airflow obstruction (UDAO) range from 3 to 12%. UDAO is a nonspecific physiologic abnormality that may be caused by a number of factors (eg, cigarette smoking) and can be the manifestation of many different disorders. The higher occurrence of UDAO among men, current or former smokers, and with advancing age provide preliminary evidence on probable causes and diagnoses (ie, chronic obstructive pulmonary disease). While cigarette smoking is associated with UDAO, a substantial proportion of persons have never smoked, particularly among women. Few studies suggest that this condition is associated with increased morbidity and mortality. While there is currently no evidence to support screening for UDAO, case-finding may have a role among persons with respiratory symptoms, who have ever smoked, with a family history of respiratory disease, or with occupational exposures to dusts or fumes.

Health-related quality of life and mortality in male patients with chronic obstructive pulmonary disease

To assess whether generic and specific health-related quality of life (HRQL) are independently associated with total and specific mortality in patients with chronic obstructive pulmonary disease (COPD), we followed until 1999 a cohort of 321 male patients with COPD, recruited in 1993-1994 at outpatient respiratory clinics. Baseline characteristics recorded under stable clinical conditions included forced spirometry, arterial blood gas tensions, dyspnea scales, 11 comorbid conditions, St. George's Respiratory Questionnaire (SGRQ), and SF-36 Health Survey. Vital status was assessed through reinterviews, the Mortality Register, and clinical records. Subjects who died (106) were older (69.8 versus 62.5 years) (p < 0.001), had lower body mass index (BMI) (25.4 versus 27.1) (p < 0.01), were more impaired in the clinical characteristics studied (%FEV(1), 34.0 versus 51.0) (p < 0.001), and had long-term oxygen therapy more frequently (31% versus 7%) (p < 0.001). Survival was shorter when worse HRQL was reported. SGRQ total and SF-36 physical summary scores were independently associated with total and respiratory mortality in Cox models, including age, FEV(1), and BMI. The total mortality-standardized hazard ratios for both HRQL measures were 1.3, whereas those for FEV(1) were 1.6. HRQL measures provide independent and relevant information on the health status of male patients with COPD. Their use should be considered for a more thorough evaluation and staging of patients with COPD.

Trends in asthma morbidity and mortality in Japan between 1984 and 1996

PURPOSE

To determine whether the increased prevalence of asthma in Japan has influenced its mortality.

MATERIALS AND METHODS

A descriptive study was conducted by the data obtained from Patient Survey and Vital Statistics of Japan between 1984 and 1996. Asthma fatalities were expressed as the number of deaths from asthma per 100,000 asthmatic patients receiving medical treatment on the day when the survey was conducted.

RESULTS

Mortality, prevalence and asthma fatalities showed different changing patterns among several age groups. Asthma mortality for the 10-24 and 25-44 year-old groups increased during the study period, while for other age groups, it decreased. The prevalence increased for all groups classified by age and sex. Asthma fatalities peaked in 1987 among the 10-24, 25-44 and 45-64 year-old groups, and decreased for others throughout the study period.

CONCLUSIONS

There is a possibility that an age-specific phenomenon is at work here because asthma mortality increased only in the 10-24 and 25-44 year-old groups, although the prevalence of asthma increased in all groups, whether classified by age or sex. The asthma fatality of the 10-24, 25-44 and 45-64 year-old groups peaked in 1987: it is conceivable that this was influenced by the particular drug therapy used. The increase in asthma mortality in the 10-24 and 25-44 year-olds might be influenced by the increased prevalence.

Accuracy of recorded asthma deaths in Denmark in a 12-months period in 1994/95

Many studies of asthma mortality rely on official registration. The aim of this study was to evaluate the accuracy of death certificates, where asthma was coded as cause of death. In a 12-month period, medical information on all subjects with asthma officially coded as the underlying cause of death in Denmark, was obtained by reviewing hospital records, contacting general practitioners and sometimes close relatives. A panel of four pulmonologists each examined the obtained information and independently assessed the cause of death. Of a total of 218 death certificates, 39 were excluded as the cause of death could not be validated. In 16 (9%) of the subjects death from asthma was judged to be the definite cause of death and in 12 (7%) death from asthma was possible. Of 151 non-asthma deaths coded as due to asthma, 109 were judged to have suffered or died from COPD and 14 from heart disease. The accuracy of Danish death certification in asthma deaths is poor, especially in the elderly, where COPD is often classified as asthma. We conclude that the true asthma mortality in Denmark is substantially lower than officially recorded.

Clinical course and prognosis of patients with chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a basically benign disease, but the prognosis is so poor that the mortality rate is similar to some malignant diseases. Depending on the disease severity, the 5-year mortality rate of patients with COPD varies from 40 to 70%. The three major causes of death have been identified as COPD itself, lung cancer, and cardiovascular disease. The following factors have been reported to be related to survival: FEV1 (especially the maximal attainable lung function), age, gender, PaO2, PaCO2, body weight, and comorbidity. There have been several large-scale randomized clinical trials to examine the prophylactic effects of inhaled anti-cholinergics and inhaled corticosteroids on the annual decline in FEV1. However, unfortunately, in all of the published studies, these drugs had no effect on the annual decline in FEV1.

Decrease in asthma mortality rate in Israel from 1991-1995: is it related to increased use of inhaled corticosteroids?

BACKGROUND

Asthma mortality rates (AMRs) during the last several decades increased in many countries with developed medical services, including Israel. The reasons for this trend were never established. Recent data suggested that this trend is changing.

OBJECTIVES

We sought to compare the AMR in Israel during 1991-1995 with that of the previous decade and to investigate a possible correlation between mortality rates and use of inhaled corticosteroids (ICSs) and beta(2)-agonists.

METHODS

Statistical data on the AMR in Israel during 1981-1995 were extracted. Data were analyzed for 5- and 10-year periods (1981-1990) and compared with a 5-year period (1991-1995). Data on ICS and beta(2)-agonist sales were extracted from the marketing companies' official reports.

RESULTS

The mean AMR per 100,000 population per year during 1981-1990 in the 5- to 34-year-old group was 0.393 +/- 0.055 and decreased to 0.202 +/- 0. 046 during the 1991-1995 period (P =.03). There was no significant difference between changes in mean AMR in the 35- to 64-year-old or in the 5- to 64-year-old group during the same periods (4.568 vs 4. 063 and 2.480 vs 2.133). The mean ICS unit sales rates (per 100,000 population per year) between 1982-1990 and 1991-1995 were 21.70 and 190.45, respectively (P <.05). The correlation between ICS sales and AMR was -0.631 (P =.016). Sales of beta(2)-agonists did not change significantly during the study period.

CONCLUSIONS

We identified a trend of decreased AMRs in Israel during 1991-1995. The decline in AMRs paralleled the increase in ICS sales, whereas the sales of inhaled beta(2)-agonists did not change significantly. One may speculate that the decrease in AMR may be the result of better anti-inflammatory treatment, as reflected by the increased use of ICSs. The feasibility of reducing AMRs in a country such as Israel, with low AMRs to start with, by improving medical treatment is encouraging.

A confidential enquiry into certified asthma deaths in the North of England, 1994-96: influence of co-morbidity and diagnostic inaccuracy

To understand more fully the nature of events leading to asthmatic death, we conducted a confidential enquiry prospectively throughout 1994-96 among the surviving relatives and respective general practitioners of subjects whose deaths could be attributed to asthma, whether wholly or partly. We also reviewed relevant hospital records and autopsy reports, and we submitted all the gathered information to an enquiry panel for evaluation. The subjects were identified from death certificates issued in five districts of the Northern Health Region of England (population 1 million) on which asthma was recorded as the primary cause of death. The enquiry panel agreed that asthma had been a critical factor in causing death in only 33 of the 79 certified cases for which there were sufficient data. The level of concordance was substantially greater for subjects aged < 65 years (76%) than for those who were older (17%). In 16 of the 33 cases asthma alone appeared to be responsible for death, but in 17 cases a wide variety of additional, co-morbid, disorders appeared to have contributed. They included, during the 24 h preceding death, gastric aspiration, septicaemia, a single dose of a beta-blocker, the abuse of organic solvents or illicit drugs and possibly, an inadvertent exposure to horse allergen. More chronic causes of co-morbidity included ischaemic heart disease, chronic obstructive pulmonary disease (COPD), thoracic cage deformity and alcohol abuse. There were possible errors of judgement in two cases by the supervising physician (6%) and in three cases by the patient (9%). Poor compliance and psychosocial disruption probably exerted an additional adverse influence in nine cases (27%). We conclude: (1) that asthma death certification in subjects aged 65 years or more is very unreliable, (2) that for approximately half of the deaths in which asthma exerted a critical role there were critical co-morbid disorders and (3) that errors of judgement, poor compliance, or psychosocial disruption are likely to have exerted an additional adverse influence in an important minority of cases.

A confidential inquiry into asthma deaths in Wales

BACKGROUND

Death from asthma is regarded as preventable in principle, especially under the age of 65 years.

METHODS

In 1994 a confidential inquiry was set up to investigate deaths attributable to asthma in residents of Wales under the age of 65 years. During the period of the inquiry 92 cases were notified as being ascribed to asthma, or (in 1996) having a mention of asthma on the death certificate. Of these, 80 were investigated further with the help of general practitioners, hospital notes, and relatives. The details were then considered by a small panel of doctors who endeavoured to identify factors that may have contributed to the deaths.

RESULTS

Asthma was considered to be the underlying cause of 52 deaths. Although disease severity was usually a major factor, some aspect of the patient's behaviour or circumstances seemed to have contributed to 31 deaths, while in 15 cases there was probably a deficiency in medical care.

CONCLUSIONS

Some preventable asthma deaths still occur, particularly in relation to inadequate treatment. Factors associated with patients' behaviour and circumstances are more difficult to tackle but, if doctors are aware of high risk patients, increased vigilance may prevent some deaths.

The natural history of asthma in adults: the problem of irreversibility

Asthma is common, affecting 5% to 10% of adults; asthma is progressive, leading to irreversible obstruction in 80% of elderly patients; and asthma is complex, often complicated by coexisting lung diseases. This loss of lung function results from 4 independent pathologic conditions: (1) airway remodeling, especially in the small airways, from the lymphocytic-eosinophilic inflammation that characterizes asthma; (2) bronchiectasis; (3) postinfectious pulmonary fibrosis; and (4) emphysema and chronic bronchitis from tobacco smoke. Deterioration in lung function develops faster in nonallergic patients with intrinsic asthma during the period shortly after onset of asthma and in older patients. About 4% of patients die of asthma, and most are elderly. Death most often results from complications of irreversible obstruction or cardiotoxicity of bronchodilator therapy. More research is needed to improve therapy for preventing remodeling of small airways, to confirm the frequency of bronchiectasis and postinfectious fibrosis and to determine their causes, and to develop diagnostic criteria to identify these complications. Meanwhile, clinicians treating adult asthmatic patients need to be aggressive in preventing the damage from cigarette smoke; in immunizing for influenza and pneumococcus infection and identifying and treating respiratory infections, particularly at times of acute exacerbations; in diagnosing and managing bronchiectasis; and in objectively confirming the efficacy of asthma therapy to prevent illness from overtreatment with glucocorticoids and bronchodilators.

Ill-defined and multiple causes on death certificates--a study of misclassification in mortality statistics

Biases can distort, limit or inhibit the value of mortality data as an epidemiological re source. From 9500 deaths occurring in Naples (Italy during 1994, a random sample of 372 death certificates reporting ill-defined causes and multiple causes of death was extracted. The code for the underlying cause on the death certificate (assigned code) was compared with the cause reattributed with the aid of interview of the certifying physician or clinical records (modified code). The aim was to investigate the extent of misclassification of 'underlying cause' in deaths attributed to ill-defined and/or multiple causes and the shortcomings in the ICD-IX. Ill-defined underlying causes of death (7.0% of death certificates) were cardiovascular diseases, tumours with no specified site or nature, symptoms, signs, ill-defined conditions and senility. There was disagreement between the initially assigned code and the modified code in 53.8% of ill-defined underlying causes; discordance was high for the certificates filled in by the family physician. Multiple causes of death were observed in 23.6% of certificates; of these 59.2% concerned subjects aged 75 years and over at death. Diabetes was always listed in association with other pathologies but neoplasms and traumas were generally listed alone. Disagreement between codes occurred in 48 (54.5%) certificates indicating multiple causes. In 10 of them, death was established as due to a concurrence of causes. As regards ill-defined causes of death, the authors concluded that specific training on certifying procedures would be insufficient on their own; the physician should be made aware that certification is a fundamental requirement for building up epidemiological data. Evidence-based educational interventions are needed. As regards multiple causes of death, multicausal analysis may be indicated for deaths due to a concurrence of causes.

Asthma in older people

From the clinical perspective, asthma in the older patient may be difficult to diagnose because of the non-specificity of presentation and the wide range of differential diagnoses. Prior to confirmation of asthma in the older patient, both respiratory and cardiac investigation may be necessary. Polypharmacy is inherent in treating older people and accurate drug histories are essential in order to identify patients with drug-induced bronchospasm and avoid interactions with asthma medication. Patient and carer education is vital, and a structured approach to follow-up which includes measurement of lung function and assessment of inhaler technique should be carried out in every asthmatic regardless of age. Finally, there is a great need for health services and those in the commercial sector that are involved in asthma care to ensure that future research and development rises to the challenge of an ageing population.

Asthma mortality in Columbia

BACKGROUND

Asthma mortality rates have increased in several industrialized countries during the past two decades. In Latin America, there have been reported only a few national studies of asthma mortality.

OBJECTIVE

To determine asthma mortality rates in Colombia from 1979 to 1994.

METHODS

Death certificates from the National Administrative Statistical Department of Colombia were collected and analyzed.

RESULTS

For the entire population we found increasing rates of asthma mortality from 2.15 in 1979 to 3.3 in 1985 followed by a decrease to 1.6 in 1994. Overall, the trend has been to decrease, with a variation coefficient of 1.09% by year. Age-adjusted rates of death from asthma, based on the population distribution of 1973, showed the same decreasing trend. Deaths from asthma were more frequent in subjects older than 35 years as compared with those younger than 5 years of age or the age group ranging from 5 to 34 years. For the latter, rates of death increased from 0.32 in 1980 to 0.37 in 1988, and fell to 0.20 in 1991. From 1992 to 1994 rates for 5 to 34 years of age were higher than previously, increasing to 0.9 in 1992 and decreasing to 0.6 in 1994. There was no significant variation in death rates between men and women. Sixty-two percent of deaths from asthma occurred at home, 31% at hospitals, and 6.7% in other places. Most asthma deaths were in urban areas.

CONCLUSIONS

In contrast to that observed in industrialized countries, we found a decreasing trend in asthma mortality in Colombia. Rates of death from asthma, however, are still high in this country.