Sarah Appleton

Diabetes and Cardiovascular Disease Outcomes in the Metabolically Healthy Obese Phenotype: A cohort study

OBJECTIVE To determine the correlates of the “metabolically healthy obese” (MHO) phenotype and the longitudinal risks of diabetes and cardiovascular disease (CVD)/stroke associated with this phenotype. RESEARCH DESIGN AND METHODS The North West Adelaide Health Study is a prospective cohort study of 4,056 randomly selected adults aged ≥18 years. Participants free of CVD/stroke and not underweight (n = 3,743) were stratified by BMI categories and metabolic risk, defined as having two or more International Diabetes Federation metabolic syndrome criteria, excluding waist circumference. RESULTS Correlates of the MHO (n = 454 [12.1%]) included smoking, socioeconomic disadvantage, and physical inactivity. Compared with metabolically healthy normal-weight subjects (n = 1,172 [31.3%]), the MHO were more likely to develop metabolic risk (15.5 vs. 33.1%, P < 0.001) and incident diabetes (odds ratio 2.09 [95% CI 0.87–5.03]) but not CVD/stroke (1.16 [0.58–2.29]) during 5.5–10.3 years of follow-up. These risks were not seen in MHO subjects maintaining metabolic health (n = 188 [67%]). Sustained metabolic health in obese participants was associated with age ≤40 years and lower waist circumference. Compared with the metabolically at-risk obese, MHO women demonstrated a significantly higher (mean [SE]) percentage of leg fat (49.9 [0.5] vs. 53.2 [0.7]) and lower waist circumference (104 [0.6] vs. 101 cm [0.8]), despite no significant differences in overall adiposity. CONCLUSIONS “Healthy” obesity was a transient state for one-third of subjects. Persistence of a MHO phenotype, which was associated with favorable outcomes, was related to younger age and a more peripheral fat distribution. The MHO phenotype may be sustained by promoting lower waist circumferences.

How valid are self-reported height and weight? A comparison between CATI self-report and clinic measurements using a large cohort study

Objective: To examine the relationship between self‐reported and clinical measurements for height and weight in adults aged 18 years and over and to determine the bias associated with using household telephone surveys.

Underdiagnosed asthma in South Australia

Background: The prevalence of undiagnosed asthma in the general population and the clinical and demographic characteristics of these patients compared with those with diagnosed asthma are unclear. Methods: The North West Adelaide Health Survey (NWAHS) is a population household interview survey of adults (age >18 years) in the north western suburbs of Adelaide, South Australia (regional population 0.6 million). Data obtained were weighted to the closest census data to provide population representative estimates. Positive answers to: “Have you ever had asthma?”; “Has it been confirmed by a doctor?”; ”Do you still have asthma?” determined current physician diagnosed asthma. A positive bronchodilator response on spirometric testing according to ATS criteria without a physician’s diagnosis determined undiagnosed asthma. Other measures included the SF-12 health survey questionnaire, the Selim index of severity of chronic lung disease, skin allergy tests, and demographic data. Results: Of the 3422 individuals interviewed, 2523 (74%) agreed to participate in the clinical assessment. Of these, 292 (11.6%) had asthma, 236 (9.3%) with a doctor’s diagnosis of asthma and 56 (2.3%) with undiagnosed asthma defined on spirometric criteria; thus, 19.2% of the total asthma group were undiagnosed. Those undiagnosed were more likely (p<0.05) to be >40 years old, on government benefits, with an income <AUD

Effects of area deprivation on health risks and outcomes: a multilevel, cross-sectional, Australian population study

40 000. Symptom frequency was similar in the two asthma groups, but mean spirometric values were lower in the undiagnosed group (p<0.05) while positive skin allergy tests were more common in the diagnosed group (p<0.05). SF-12 component summary scores were significantly lower in both asthma groups than in the non-asthma population. Undiagnosed asthma was frequent in men and in those aged >65 years. Health service use over the previous year was similar for both asthma groups. Conclusion: Undiagnosed asthma is common among the Australian population, with a similar clinical spectrum to those with diagnosed asthma.

Endothelial cell activation in vasculitis of peripheral nerve and skeletal muscle.

Objectives:Our aim was to examine the effect of local area socio-economic disadvantage after accounting for individual socio-economic status (SES), and to determine if these differ between various health and risk factor variables.Methods:The North West Adelaide Health Study (NWAHS) is a biomedical representative population study of adults. The Index of Relative Socio-Economic Disadvantage (IRSD), produced from the Australian Bureau of Statistics (ABS) Census data at the level of Collector Districts (200 dwellings) was used as an indicator of local area disadvantage. Multi-level modeling techniques examined the effects of IRSD level on a variety of health outcomes and risk factors, after accounting for individual socio-economic factors.Results:Significant, independent associations were seen between IRSD and obesity, smoking, and health-related quality of life, with 5 % to 7.2 % of the variance located at the neighborhood level. No independent associations were seen between IRSD and estimated cardiovascular disease risk, diabetes, physical activity, or at-risk alcohol use.Conclusions:Aggregated area-level characteristics make modest, but significant independent contributions to smoking, obesity and quality of life, but not for other health outcomes.

Independent Association of HbA1c and Incident Cardiovascular Disease in People Without Diabetes

To clarify the role of endothelial cells in the pathogenesis of vasculitis affecting peripheral nerve and skeletal muscle, the endothelial expression of adhesion molecules and major histocompatibility antigens (MHC) in different vasculitic syndromes were studied, and related to the presence of anti-endothelial cell antibodies (AECA). Increased expression of the intercellular adhesion molecule ICAM-1 in vasculitic lesions in nerve and muscle was shown, and this was associated with increased expression of MHC class I and II antigens. AECA were detected in low titre in only a minority of patients. The findings suggest that endothelial cells have a critical role in mediating the tissue injury in vasculitis affecting nerve and muscle and that the process is triggered by cellular and not antibody-mediated mechanism in the majority of patients.

Cause for concern in the use of non-steroidal anti-inflammatory medications in the community -a population-based study

Recent studies have reported no association between elevated glycated hemoglobin (HbA1c) and incident cardiovascular disease (CVD) among women without diabetes. This study describes associations between HbA1c and new onset CVD in a representative adult population cohort. Assessment of participants in The North West Adelaide Health Study (NWAHS), a population study of randomly selected adults (age ≥18 years, n = 4,060), included measurement of height, weight, blood pressure, fasting lipids, glucose, and HbA1c. A self‐completed questionnaire assessed doctor‐diagnosed diabetes, CVD and stroke, smoking status, and demographics. The cohort was followed for an average 3.5 years. Of the 2,913 adults free of diabetes at baseline and follow‐up, 94 (3.5%) reported new onset coronary heart disease (CHD) and/or stroke. Compared with those with an HbA1c ≤5.0%, risk of new onset CVD was increased in those with HbA1c 5.4–5.6% (odds ratio (OR) 2.5, 95% confidence interval (CI) 1.4, 4.6), and ≥5.7% (OR 1.9, 95% CI 1.1, 3.4), after adjustment for other risk factors. The association was stronger in women than men (P = 0.03), and attenuated to only a small degree by addition of impaired fasting glucose (IFG), hypertension, hypercholesterolemia, BMI, waist circumference, or smoking to the model. Elevated HbA1c is related to new onset CVD over a relatively short follow‐up period in both men and women without diabetes and who do not develop diabetes, after adjustment for other major risk factors. Unlike previous studies, this relationship was not substantially attenuated by other traditional risk factors.

Participatory Decision Making, Asthma Action Plans, and Use of Asthma Medication: A Population Survey

BackgroundNon-steroidal anti-inflammatory (NSAID) medications are a common cause of reported adverse drug side-effects. This study describes the prevalence of non-steroidal anti-inflammatory (NSAID) use (other than low-dose aspirin) and the presence of co-existing relative contraindications to NSAID use and chronic conditions in a representative population sample.MethodsData were analysed from 3,206 adults attending first follow-up of the North West Adelaide Health Study (NWAHS) in 2004 - 2006, a longitudinal representative population study. Medications were brought into study clinic visits by participants. Clinical assessment included measured blood pressure, kidney function, serum cholesterol, blood glucose. Questionnaires assessed demographics, lifestyle risk factors, physician-diagnosed chronic conditions. Data were weighted to census measures by region, age group, gender, and probability of selection in the household, to provide population representative estimates. Pearsons Chi-square tests determined significant differences in proportions. Multiple logistic regression was used to examine associations of socio-demographic characteristics with use of NSAIDs.ResultsOf 3,175 participants, 357 (11.2%), and 16% of those aged > 55 years, reported using either non-specific NSAIDs or COX-2 inhibitors, other than low-dose aspirin. Among people using NSAIDs, 60.8% had hypertension, 30.8% had Stage 3 or higher chronic kidney disease, 17.2% had a history of cardiovascular disease (CVD) and 20.7% had a > 15% 10-year CVD risk. The prevalence of NSAID use among people with hypertension was 16%, with kidney disease 15.9%, and a history of CVD 20.0%. Among people taking diuretics, 24.1% were also taking NSAIDs, and of those taking medications for gastro-esophageal reflux, 24.7% were on NSAIDs. Prescription-only COX-2 inhibitors, but not other NSAIDs, were used more by people > 75 years than by 35-54 year olds (OR 3.7, 95% CI 2.0, 6.7), and also were more commonly used by people with hypertension, cardiac and kidney disease.ConclusionsThere is a high prevalence of current NSAID use among groups at-risk for significant drug-related adverse events or who have major chronic conditions that are relative contraindications to NSAID use. Assessment of absolute risks regarding cardiovascular and kidney disease need to take into account use of medications such as NSAIDs. The potential to make a substantial impact on chronic disease burden via improved use of NSAIDs is considerable.

Cardiovascular disease risk associated with asthma and respiratory morbidity might be mediated by short-acting β2-agonists

Use of controller asthma medication and possession of asthma action plans remains suboptimal. Our aim was to investigate the association of the propensity of physicians to involve patients in their care (participatory decision-making style) and their asthma management in a representative population sample of 3015 adults. Current doctor-diagnosed asthma was reported by 393 (13.0%). People who rated their doctors as more participatory were significantly more likely to report more regular use of controller medications and possession of a written asthma action plan, but not less asthma morbidity. Possession of a written action plan was associated with more participatory interactions (OR 2.3; 95% CI 1.1–4.7, for upper tertile scores compared to lowest tertile); more severe symptoms (OR 4.8; 95% CI 1.7–13.0), being female (OR 2.2; 95% CI 1.2–4.3), those with higher education, and residence outside the metropolitan area (OR 2.1; 95% CI 1.1–4.0). Increasing patient participation in their own care is associated with better asthma management, independent of asthma symptoms. Longitudinal studies are needed to examine if increasing participation in decisions can also improve asthma outcomes.

Inadequate health literacy is associated with increased asthma morbidity in a population sample

BACKGROUND Studies examining the asthma-related risks of cardiovascular disease (CVD) events have generally used selected samples or did not control for the effects of beta(2)-agonist use, itself associated with CVD events. OBJECTIVES We assessed the relationship between incident CVD/stroke and asthma and the effect of atopy while controlling for beta(2)-agonist use in a representative adult population cohort free of CVD at baseline. METHODS The North West Adelaide Health Study (stage 1, n = 3812; stage 2, n = 3113) assessed spirometry, anthropometry, atopy, blood pressure, and lipid levels. Questionnaires assessed doctor-diagnosed asthma and CVD (myocardial infarction and angina)/stroke, smoking status, and demographics. Asthma was defined by self-report or FEV(1) reversibility. Current short- and long-acting beta(2)-agonist use was identified at follow-up. RESULTS Results are expressed as odds ratios (ORs) and 95% CIs. By using multivariable logistic regression, after adjustment for risk factors, in female subjects incident CVD/stroke events were associated with asthma (OR, 3.24; 95% CI, 1.55-6.78), with no effect modification by atopy (P for interaction = .61), and with as-required short-acting beta(2)-agonist use (OR, 2.66; 95% CI, 1.06-6.61). In male subjects events were associated with daily cough/sputum (OR, 1.92; 95% CI, 1.05-3.50) and FEV(1) of less than 80% of predicted value but an FEV(1)/forced vital capacity ratio of greater than 0.70 (OR, 2.15; 95% CI, 0.91-5.09; P = .08). Although few CVD/stroke events occurred in male subjects with asthma, a significant interaction with atopic status was found (P = .05). CONCLUSIONS Studies are required to elucidate how asthma exposes older women to excess macrovascular risk and prospectively determine the short-acting beta(2)-agonist-related risk in persons without existing CVD. CVD risk in relation to atopic status of asthma also requires further investigation.