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H Ross Anderson

Publications and source records attributed to H Ross Anderson.

11 recordsLinked to original sources
PubMed2007

50 years of asthma: UK trends from 1955 to 2004.

Trends in asthma indicators from population surveys (prevalence) and routine statistics (primary care, prescriptions, hospital admissions and mortality) in the UK were reviewed from 1955 to 2004. The prevalence of asthma increased in children by 2 to 3-fold, but may have flattened or even fallen recently. Current trends in adult prevalence are flat. The prevalence of a life-time diagnosis of asthma increased in all age groups. The incidence of new asthma episodes presenting to general practitioners increased in all ages to a plateau in the mid 1990s and has declined since. During the 1990s, the annual prevalence of new cases of asthma and of treated asthma in general practice showed no major change. Hospital admissions increased from the early 1960s, more so in children, until the late 1980s and have fallen since. Asthma mortality showed two waves, a shorter and more intense one in the mid 1960s and a longer and less intense one in the late 1970s and early 1980s. The relative roles of diagnostic transfer, coding changes, medical care and epidemiological factors are discussed.

Adolescent↗
PubMed2006

Childhood chest illness and the rate of decline of adult lung function between ages 35 and 45 years.

RATIONALE: There is an association between childhood chest illness and impairment of adult ventilatory function. It has not yet been established whether respiratory illness in childhood predisposes to chronic obstructive pulmonary disease by accelerating the decline in adult lung function. OBJECTIVES: To determine the effects of childhood chest illness and smoking on the rate of decline of adult ventilatory function from the age of 35 to 45 yr in a large, nationally representative sample of British adults. METHODS: Spirometry measurements were compared at 35 and 45 yr of age in 1,158 adults participating in the British 1958 Birth Cohort. Multiple regression analysis was used to measure the association between childhood chest illness and within-person change in spirometric volumes between age 35 and 45 yr, adjusting for potential confounding factors. MEASUREMENTS AND MAIN RESULTS: The mean reduction in FEV(1) between ages 35 and 45 yr was 35 ml/yr. Compared with subjects without the relevant respiratory history, the rate of decline was not significantly associated with pneumonia (mean difference, -0.2; 95% confidence interval, -6.1 to +5.8 ml/yr), whooping cough (0.7, -5.1 to +6.5 ml/yr), wheeze by age 7 yr (0.4, -5 to +5.9 ml/yr), or wheeze onset by age 8 to 16 yr (-3.4, -10.5 to +3.6 ml/yr). A similar pattern emerged for forced vital capacity. CONCLUSIONS: Childhood chest illness does not adversely affect the rate of decline of lung function in mid-adult life.

Adolescent↗
PubMed2005

Ambient particulate matter and health effects: publication bias in studies of short-term associations.

BACKGROUND: Time-series studies have shown short-term temporal associations between low levels of ambient particulate air pollution and adverse health effects. It is not known whether or to what extent this literature is affected by publication bias. METHODS: We obtained effect estimates from time-series studies published up to January 2002. These were summarized and examined for funnel plot asymmetry. We compared summary estimates between single-city and prospective multicity studies. Using 1 multicity study, we examined the sensitivity of summary estimates to alternative lag selection policies. RESULTS: We found evidence for publication bias among single-city studies of daily mortality, hospital admissions for chronic obstructive lung disease (COPD), and incidence of cough symptom, but not for studies of lung function. Statistical correction for this bias reduced summary relative risk estimates for a 10 microg/m increment of particulate matter less than 10 microm aerodynamic diameter (PM10) as follows: daily mortality from 1.006 to 1.005 and admissions for COPD from 1.013 to 1.011; and odds ratio for cough from 1.025 to 1.015. Analysis of results from a large multicity study suggested that selection of positive estimates from a range of lags could increase summary estimates for PM10 and daily mortality by up to 130% above those based on nondirectional approaches. CONCLUSION: We conclude that publication bias is present in single-city time-series studies of ambient particles. However, after correcting for publication bias statistically, associations between particles and adverse health effects remained positive and precisely estimated. Differential selection of positive lags may also inflate estimates.

Air Pollutants↗
PubMed2004

Bronchodilator treatment and deaths from asthma: case-control study.

OBJECTIVE: To investigate the association between bronchodilator treatment and death from asthma. DESIGN: Case-control study. SETTING: 33 health authorities or health boards in Great Britain. PARTICIPANTS: 532 patients under age 65 who died from asthma and 532 controls with a hospital admission for asthma matched for period, age, and area. MAIN OUTCOME MEASURES: Odds ratios for deaths from asthma associated with prescription of bronchodilators and other treatment, with sensitivity analyses adjusting for age at onset, previous hospital admissions, associated chronic obstructive lung disease, and number of other drug categories. RESULTS: After full adjustment, there were no significant associations with drugs prescribed in the 4-12 months before the index date. For prescriptions in the 1-5 years before, mortality was positively associated with inhaled short acting beta2 agonists (odds ratio 2.05, 95% confidence interval 1.26 to 3.33) and inversely associated with antibiotics (0.59, 0.39 to 0.89). The former association seemed to be confined to those aged 45-64, and the association with antibiotics was more pronounced in those under 45. Significant age interactions across all periods suggested inverse associations with oral steroids confined to the under 45 age group. An inverse association with long acting beta2 agonists and a positive association with methylxanthines in the 1-5 year period were non-significant. CONCLUSION: There was no evidence of adverse effects on mortality with medium to long term use of inhaled long acting beta2 agonist drugs. The association with short acting beta(2) agonists has several explanations, only one of which may be a direct adverse effect.

Adolescent↗
PubMed2004

Acute effects of ozone on mortality from the "air pollution and health: a European approach" project.

In the Air Pollution and Health: A European Approach (APHEA2) project, the effects of ambient ozone concentrations on mortality were investigated. Data were collected on daily ozone concentrations, the daily number of deaths, confounders, and potential effect modifiers from 23 cities/areas for at least 3 years since 1990. Effect estimates were obtained for each city with city-specific models and were combined using second-stage regression models. No significant effects were observed during the cold half of the year. For the warm season, an increase in the 1-hour ozone concentration by 10 mug/m3 was associated with a 0.33% (95% confidence interval [CI], 0.17-0.52) increase in the total daily number of deaths, 0.45% (95% CI, 0.22-0.69) in the number of cardiovascular deaths, and 1.13% (95% CI, 0.62-1.48) in the number of respiratory deaths. The corresponding figures for the 8-hour ozone were similar. The associations with total mortality were independent of SO2 and particulate matter with aerodynamic diameter less than 10 mum (PM10) but were somewhat confounded by NO2 and CO. Individual city estimates were heterogeneous for total (a higher standardized mortality rate was associated with larger effects) and cardiovascular mortality (larger effects were observed in southern cities). The dose-response curve of ozone effects on total mortality during the summer did not deviate significantly from linearity.

Air Pollutants↗
PubMed2002

A tale of two cities: effects of air pollution on hospital admissions in Hong Kong and London compared.

The causal interpretation of reported associations between daily air pollution and daily admissions requires consideration of residual confounding, correlation between pollutants, and effect modification. If results obtained in Hong Kong and London--which differ in climate, lifestyle, and many other respects--were similar, a causal association would be supported. We used identical statistical methods for the analysis in each city. Associations between daily admissions and pollutant levels were estimated using Poisson regression. Nonparametric smoothing methods were used to model seasonality and the nonlinear dependence of admissions on temperature, humidity, and influenza admissions. For respiratory admissions (> or = 65 years of age), significant positive associations were observed with particulate matter < 10 microm in aerodynamic diameter (PM(10), nitrogen dioxide, sulfur dioxide, and ozone in both cities. These associations tended to be stronger at shorter lags in Hong Kong and at longer lags in London. Associations were stronger in the cool season in Hong Kong and in the warm season in London, periods during which levels of humidity are at their lowest in each city. For cardiac admissions (all ages) in both cities, significant positive associations were observed for PM(10), NO(2), and SO(2) with similar lag patterns. Associations tended to be stronger in the cool season. The associations with NO(2) and SO(2) were the most robust in two-pollutant models. Patterns of association for pollutants with ischemic heart disease were similar in the two cities. The associations between O(3) and cardiac admissions were negative in London but positive in Hong Kong. We conclude that air pollution has remarkably similar associations with daily cardiorespiratory admissions in both cities, in spite of considerable differences between cities in social, lifestyle, and environmental factors. The results strengthen the argument that air pollution causes detrimental short-term health effects.

Adolescent↗
PubMed2002

Association between migraine and asthma: matched case-control study.

BACKGROUND: Earlier studies have suggested a link between asthma and severe headache, and also between migraine and wheezing illness. Recent analysis have also shown an increase of asthma among cases with a prior history of migraine but without a history of hay fever, allergic rhinitis or eczema. AIM: To examine whether there is an association between migraine and asthma in the United Kingdom. DESIGN OF STUDY: Matched case-control study using the General Practice Research Database (GPRD). SETTING: Practices in the United Kingdom providing data on 5,110,619 patients to the GPRD. METHOD: The subjects were the patients with one or more diagnoses of migraine plus treatment for migraine. Each case was matched by general practice, sex, and age, with one control who had never been given a diagnosis of migraine. Case and control groups were compared for prevalence of asthma, chronic obstructive pulmonary disease, respiratory symptoms treated with inhalers or hay fever. Investigations were carried out to determine whether the association between migraine and asthma was stronger among patients with hayfever or those without hayfever, and whether patients with migraine had an increased prescription of other (non-migraine and non-asthma) medications. RESULTS: Among 64 678 case-control pairs, the relative risk of asthma in patients with migraine was 1.59 (95% CI = 1.54 to 1.65) among definite cases, and 0.75 (95% CI = 0.67 to 0.83) among those whose selection as case included beta-blocker prophylaxis. Among definite migraine cases, relative risks of chronic obstructive pulmonary disease, respiratory symptoms, eczema, and hay fever (pollinosis), were all raised (at 1.22, 1.85, 1.55, and 1.67, respectively). The association between migraine and asthma was stronger in patients without a diagnosis of hay fever, than in those with hayfever (relative risk = 1.32 and 1.19, respectively). The relative risk of prescription for a range of non-migraine, non-asthma medications was raised, the exception being anti-diabetic medication. CONCLUSION: This large case-control study provides evidence for an association between migraine and asthma. Frequent attendance at a general practice surgery may confound this association. However, if the association is real, its elucidation may help the understanding of disease mechanisms shared by migraine and asthma.

Asthma↗
PubMedDate not supplied

The global burden of disease due to outdoor air pollution.

As part of the World Health Organization (WHO) Global Burden of Disease Comparative Risk Assessment, the burden of disease attributable to urban ambient air pollution was estimated in terms of deaths and disability-adjusted life years (DALYs). Air pollution is associated with a broad spectrum of acute and chronic health effects, the nature of which may vary with the pollutant constituents. Particulate air pollution is consistently and independently related to the most serious effects, including lung cancer and other cardiopulmonary mortality. The analyses on which this report is based estimate that ambient air pollution, in terms of fine particulate air pollution (PM(2.5)), causes about 3% of mortality from cardiopulmonary disease, about 5% of mortality from cancer of the trachea, bronchus, and lung, and about 1% of mortality from acute respiratory infections in children under 5 yr, worldwide. This amounts to about 0.8 million (1.2%) premature deaths and 6.4 million (0.5%) years of life lost (YLL). This burden occurs predominantly in developing countries; 65% in Asia alone. These estimates consider only the impact of air pollution on mortality (i.e., years of life lost) and not morbidity (i.e., years lived with disability), due to limitations in the epidemiologic database. If air pollution multiplies both incidence and mortality to the same extent (i.e., the same relative risk), then the DALYs for cardiopulmonary disease increase by 20% worldwide.

Air Pollutants↗