Associations of physical and mental health problems with chronic cough in a representative population cohort

Background: Although chronic cough is a common problem in clinical practice, data on the prevalence and characteristics of cough in the general population are scarce. Our aim was to determine the prevalence of chronic cough that is not associated with diagnosed respiratory conditions and examine the impact on health status and psychological health, in a representative adult population cohort. Methods: North West Adelaide Health Study (n stage 1 = 4060, stage 2 = 3160) is a representative population adult cohort. Clinical assessment included spirometry, anthropometry and skin tests. Questionnaires assessed demographics, lifestyle risk factors, quality of life, mental health and respiratory symptoms, doctor diagnosed conditions and medication use. Results: Of the 3355 people without identified lung disease at baseline, 18.2% reported chronic cough. In multiple logistic regression models, at follow-up, dry chronic cough without sputum production was significantly more common in males (OR 1.5, 95% CI 1.1, 1.9), current smokers (OR 4.9, 95% CI 3.4, 7.2), obesity (OR 1.9, 95% CI 1.3, 2.9), use of ACE inhibitors (OR 1.8, 95% CI 1.1, 2.9), severe mental health disturbance (OR 2.1, 95% CI 1.4, 3.1) and older age (40-59 years OR 1.7 95% CI 1.2, 2.4; ≥ 60 years OR 2.1 95% CI 1.3, 3.5). Among non-smokers only, all cough was significantly more common in men, those with severe mental health disturbance and obesity. Conclusions: Chronic cough is a major cause of morbidity. Attention to cough is indicated in patients with obesity, psychological symptoms or smokers. Inquiring about cough in those with mental health problems may identify reversible morbidity.Robert J Adams, Sarah L Appleton, David H Wilson, Anne W Taylor and Richard E Ruffi

Trends in asthma prevalence and population changes in South Australia, 1990-2003

The document attached has been archived with permission from the editor of the Medical Journal of Australia. An external link to the publisher’s copy is included.Objectives: To examine changes in asthma prevalence in the context of other population changes between 1990 and 2003, for specific age and sex groups. Design: Cross-sectional survey based on household interviews, repeated annually. Setting and participants: Representative samples of the South Australian population between 1990 and 2003 (around 3000 people per year). Main outcome measures: Current prevalence of doctor-diagnosed asthma and other health and demographic variables potentially associated with asthma, and asthma management. Results: Response rate was over 71%. Between 1990 and 2003, asthma prevalence increased significantly, doubling in females (from 7.3% in 1990 to 14.6% in 2003), with a smaller increase in males (from 7.8% to 9.4%). Asthma also increased in all age groups, but the largest relative increases occurred in people aged 55 years and older. Logistic regression analyses showed that obesity was a major predictive variable for every age group studied. The prevalence of asthma morbidity (waking at night and days lost from usual activities because of asthma) among those with asthma showed no significant changes between 1990 and 2003. Asthma action plans (introduced on a population basis in 1992) peaked in their distribution at 42% in 1994, and then declined to half that percentage in 2003. The increase in asthma prevalence occurred at the same time as increases in population prevalence of obesity (10.3% to 18.7%) and diabetes (3.1% to 6.9%), and decline in recent vigorous exercise (42.4% to 32.7%). Conclusions: The increase in asthma prevalence over a decade was large, but concentrated among specific sex and age groups. The increase accompanied population increases in obesity and diabetes and a decline in vigorous exercise.David H Wilson, Robert J Adams, Graeme Tucker, Sarah Appleton, Anne W Taylor and Richard E Ruffi

The north west Adelaide health study: detailed methods and baseline segmentation of a cohort for selected chronic diseases

The North West Adelaide Health Study is a population-based biomedical cohort study investigating the prevalence of a number of chronic conditions and health-related risk factors along a continuum. This methodology may assist with evidence-based decisions for health policy makers and planners, and inform health professionals who are involved in chronic disease prevention and management, by providing a better description of people at risk of developing or already diagnosed with selected chronic conditions for more accurate targeting groups for health gain and improved health outcomes. Longitudinal data will provide information on progression of chronic conditions and allow description of those who move forward and back along the continuum over time. Detailed methods are provided regarding the random recruitment and examination of a representative sample of participants (n = 4060), including the rationale for various processes and valuable lessons learnt. Self-reported and biomedical data were obtained on risk factors (smoking, alcohol consumption, physical activity, family history, body mass index, blood pressure, cholesterol) and chronic conditions (asthma, chronic obstructive pulmonary disease, diabetes) to classify participants according to their status along a continuum. Segmenting this population sample along a continuum showed that 71.5% had at least one risk factor for developing asthma, chronic obstructive pulmonary disease or diabetes. Almost one-fifth (18.8%) had been previously diagnosed with at least one of these chronic conditions, and an additional 3.9% had at least one of these conditions but had not been diagnosed. This paper provides a novel opportunity to examine how a cohort study was born. It presents detailed methodology behind the selection, recruitment and examination of a cohort and how participants with selected chronic conditions can be segmented along a continuum that may assist with health promotion and health services planning.Janet F Grant, Catherine R Chittleborough, Anne W Taylor, Eleonora Dal Grande, David H Wilson, Patrick J Phillips, Robert J Adams, Julianne Cheek, Kay Price, Tiffany Gill and Richard E Ruffi

Do people with risky behaviours participate in biomedical cohort studies?

BACKGROUND: Analysis was undertaken on data from randomly selected participants of a bio-medical cohort study to assess representativeness. The research hypotheses was that there was no difference in participation and non-participations in terms of health-related indicators (smoking, alcohol use, body mass index, physical activity, blood pressure and cholesterol readings and overall health status) and selected socio-demographics (age, sex, area of residence, education level, marital status and work status). METHODS: Randomly selected adults were recruited into a bio-medical representative cohort study based in the north western suburbs of the capital of South Australia – Adealide. Comparison data was obtained from cross-sectional surveys of randomly selected adults in the same age range and in the same region. The cohort participants were 4060 randomly selected adults (18+ years). RESULTS: There were no major differences between study participants and the comparison population in terms of current smoking status, body mass index, physical activity, overall health status and proportions with current high blood pressure and cholesterol readings. Significantly more people who reported a medium to very high alcohol risk participated in the study. There were some demographic differences with study participants more likely to be in the middle level of household income and education level. CONCLUSION: People with risky behaviours participated in this health study in the same proportions as people without these risk factors

Regular use of analgesics is a risk factor for renal cell carcinoma

Phenacetin-based analgesics have been linked to the development of renal pelvis cancer and renal cell carcinoma (RCC). The relationship between non-phenacetin types of analgesics and kidney cancer is less clear, although laboratory evidence suggests that these drugs possess carcinogenic potential. A population-based case–control study involving 1204 non-Asian RCC patients aged 25–74 and an equal number of sex-, age- and race-matched neighbourhood controls was conducted in Los Angeles, California, to investigate the relationship between sustained use of analgesics and risk of RCC according to major formulation categories. Detailed information on medical and medication histories, and other lifestyle factors was collected through in-person interviews. Regular use of analgesics was a significant risk factor for RCC in both men and women (odds ratio (OR) = 1.6, 95% confidence interval (CI) = 1.4–1.9 for both sexes combined). Risks were elevated across all four major classes of analgesics (aspirin, non-steroidal anti-inflammatory agents other than aspirin, acetaminophen and phenacetin). Within each class of analgesics, there was statistically significant increasing risk with increasing level of exposure. Although there was some minor variability by major class of formulation, in general individuals in the highest exposure categories exhibited approximately 2.5-fold increase in risk relative to non- or irregular users of analgesics. Subjects who took one regular-strength (i.e. 325 mg) aspirin a day or less for cardiovascular disease prevention were not at an increased risk of RCC (OR = 0.9, 95% CI = 0.6–1.4). © 1999 Cancer Research Campaig

Prevalence, morbidity and management of adult asthma in South Australia

Copyright © 2001, Nature Publishing GroupThis paper reviews asthma-related data obtained between 1987 and 1997 from self-report population surveys of adults in South Australia. A multistage, systematic, clustered area sample of adults (>15 years) was selected from a random sample of Australian Bureau of Statistics collector districts, and interviewed at home by trained health interviewers. The self-report prevalence of doctor-diagnosed asthma increased from 5.6% in 1987 to 12.2% in 1997. Morbidity measured as days lost from usual activities and nights awoken by asthma remained high, but hospitalization rates are trending down. The ownership of asthma action plans peaked in 1995 and has declined. The ownership of peak flow meters increased between 1992 and 1997, and the ownership of nebulisers remained constant. Evidence-based interventions are required to improve asthma management.R Ruffin, D Wilson, B Smith, A Southcott and R Adam

Spirometric criteria for asthma: adding further evidence to the debate

© MosbyBACKGROUND: Objective assessments of pulmonary function are considered essential for the diagnosis of asthma. The degree of reversibility of FEV1 considered supportive of asthma varies between international asthma guidelines. OBJECTIVE: We sought to compare the relative performance of international guideline reversibility criteria for identifying impairment in persons with a significant bronchodilator response (SBR) without an asthma diagnosis. METHODS: The North West Adelaide Health (Cohort) Study, a population biomedical study of 4060 subjects, conducted spirometry according to American Thoracic Society criteria. SBR was defined as postbronchodilator FEV1 responses of at least 12% or 15% of baseline values, 9% of predicted values, or 400 mL. A self-completed questionnaire assessed current asthma (CA), respiratory symptoms, and participant demographics. RESULTS: The prevalence of CA was 9.4% (n = 380), whereas 1.3% (≥400 mL) to 4.5% (≥9% of predicted value) of participants demonstrated an SBR in the absence of CA. With the exception of the 9% predicted criterion, prebronchodilator mean FEV1 (percent predicted) in those demonstrating an SBR but no CA was significantly worse than that in the CA group. Significantly more respiratory symptoms were experienced by the SBR groups than the group without asthma. Logistic regression analyses identified different characteristics of those classified by the following criteria: 12% and 15%, age of 40 years or greater and household income of less than $40,000; 9$40,000; 400 mL, male sex (odds ratio, 4.5; 95% CI, 2.1-9.3). CONCLUSIONS: Different criteria identify different persons, but SBR by any criteria was associated with significant respiratory impairment, some of which might be attributable to asthma. Postbronchodilator change as a percentage of predicted value was the least biased of the criteria.Sarah L. Appleton, Robert J. Adams, David H. Wilson, Anne W. Taylor and Richard E. Ruffinhttp://www.elsevier.com/wps/find/journaldescription.cws_home/623368/description#descriptio

Asthma is associated with cardiovascular disease in a representative population sample

SummaryRationalePeople with asthma may have an increased risk of cardiovascular disease (CVD) and metabolic disorders due to the direct involvement of common inflammatory mediators in the pathogenesis of CVD and insulin resistance. The aim of this study was to determine whether asthma was associated with an increased prevalence of CVD/stroke, and diabetes in a cross-sectional population study and whether the relationship was modified by obesity.MethodsThe North West Adelaide Health Study (NWAHS) (n = 4060, age ≥18 years) clinical assessment included spirometry, anthropometry, blood pressure, fasting lipids, glucose and HbA1c. Questionnaires assessed doctor diagnosed asthma, diabetes, CVD (myocardial infarction, angina)/stroke, smoking status, and demographics. Asthma was identified by self-report or significant bronchodilator reversibility of lung function.ResultsAfter adjustment for known risk factors and confounders, asthma was not associated with diabetes (odds ratio (OR) = 1.06, 95% confidence interval (CI): 0.45-2.49, p = .91) yet remained positively associated with CVD/stroke (OR = 1.82, 95% CI: 1.20-2.73, p ConclusionsIn a representative population sample, asthma was associated with CVD/stroke after adjustment for traditional risk factors and lung function. Asthma may lead to CVD events via pathways unrelated to traditional risk factors and this requires further investigation. No significant effect modification by BMI was observed in relation to CVD, or diabetes.Sarah L. Appleton, Richard E. Ruffin, David H. Wilson, Anne W. Taylor, Robert J. Adam