Wang X.Y.,Queensland University of Technology |
Barnett A.G.,Queensland University of Technology |
Yu W.,Queensland University of Technology |
FitzGerald G.,Queensland University of Technology |
And 6 more authors.
Occupational and Environmental Medicine
Objectives: Heatwaves can have significant health consequences resulting in increased mortality and morbidity. However, their impact on people living in tropical/subtropical regions remains largely unknown. This study assessed the impact of heatwaves on mortality and emergency hospital admissions (EHAs) from non-external causes (NEC) in Brisbane, a subtropical city in Australia. Methods: We acquired daily data on weather, air pollution and EHAs for patients aged 15 years and over in Brisbane between January 1996 and December 2005, and on mortality between January 1996 and November 2004. A locally derived definition of heatwave (daily maximum ≥378C for 2 or more consecutive days) was adopted. Case-crossover analyses were used to assess the impact of heatwaves on cause-specific mortality and EHAs. Results: During heatwaves, there was a statistically significant increase in NEC mortality (OR 1.46; 95% CI 1.21 to 1.77), cardiovascular mortality (OR 1.89; 95% CI 1.44 to 2.48), diabetes mortality in those aged 75+ (OR 9.96; 95% CI 1.02 to 96.85), NEC EHAs (OR 1.15; 95% CI 1.07 to 1.23) and EHAs from renal diseases (OR 1.41; 95% CI 1.09 to 1.83). The elderly were found to be particularly vulnerable to heatwaves (eg, for NEC EHAs, OR 1.24 for 65-74-year-olds and 1.39 for those aged 75+). Conclusions: Significant increases in NEC mortality and EHAs were observed during heatwaves in Brisbane where people are well accustomed to hot summer weather. The most vulnerable were the elderly and people with cardiovascular, renal or diabetic disease. Source
Tong S.,Queensland University of Technology |
Wang X.Y.,Queensland University of Technology |
Fitzgerald G.,Queensland University of Technology |
Neville G.,Environmental Health Branch |
And 3 more authors.
BMC Public Health
Background: This study attempted to develop health risk-based metrics for defining a heatwave in Brisbane, Australia. Methods. Poisson generalised additive model was performed to assess the impact of heatwaves on mortality and emergency hospital admissions (EHAs) in Brisbane. Results: In general, the higher the intensity and the longer the duration of a heatwave, the greater the health impacts. There was no apparent difference in EHAs risk during different periods of a warm season. However, there was a greater risk for mortality in the 2nd half of a warm season than that in the 1st half. While elderly (≥75 years) were particularly vulnerable to both the EHA and mortality effects of a heatwave, the risk for EHAs also significantly increased for two other age groups (0 - 64 years and 65 - 74 years) during severe heatwaves. Different patterns between cardiorespiratory mortality and EHAs were observed. Based on these findings, we propose the use of a tiered heat warning system based on the health risk of heatwave. Conclusions: Health risk-based metrics are a useful tool for the development of local heatwave definitions. This tool may have significant implications for the assessment of heatwave-related health consequences and development of heatwave response plans and implementation strategies. © 2014 Tong et al.; licensee BioMed Central Ltd. Source
He M.,Sun Yat Sen University |
He M.,University of Melbourne |
Xiang F.,Sun Yat Sen University |
Xiang F.,Australian National University |
And 9 more authors.
JAMA - Journal of the American Medical Association
IMPORTANCE Myopia has reached epidemic levels in parts of East and Southeast Asia. However, there is no effective intervention to prevent the development ofmyopia. OBJECTIVE To assess the efficacy of increasing time spent outdoors at school in preventing incidentmyopia. DESIGN, SETTING, AND PARTICIPANTS Cluster randomized trial of children in grade 1 from 12 primary schools in Guangzhou, China, conducted between October 2010 and October 2013. INTERVENTIONS For 6 intervention schools (n = 952 students), 1 additional 40-minute class of outdoor activities was added to each school day, and parents were encouraged to engage their children in outdoor activities after school hours, especially during weekends and holidays. Children and parents in the 6 control schools (n = 951 students) continued their usual pattern of activity. MAIN OUTCOMES AND MEASURES The primary outcome measurewas the 3-year cumulative incidence rate ofmyopia (defined using the Refractive Error Study in Children spherical equivalent refractive error standard of≤-0.5 diopters [D]) among the students without establishedmyopia at baseline. Secondary outcome measures were changes in spherical equivalent refraction and axial length among all students, analyzed using mixed linear models and intention-to-treat principles. Data from the right eyes were used for the analysis. RESULTS There were 952 children in the intervention group and 951 in the control group with a mean (SD) age of 6.6 (0.34) years. The cumulative incidence rate of myopia was 30.4%in the intervention group (259 incident cases among 853 eligible participants) and 39.5%(287 incident cases among 726 eligible participants) in the control group (difference of -9.1% [95%CI, -14.1% to -4.1%]; P < .001). There was also a significant difference in the 3-year change in spherical equivalent refraction for the intervention group (-1.42 D) compared with the control group (-1.59 D) (difference of 0.17 D [95%CI, 0.01 to 0.33 D]; P = .04). Elongation of axial length was not significantly different between the intervention group (0.95 mm) and the control group (0.98 mm) (difference of -0.03mm[95%CI, -0.07 to 0.003 mm]; P = .07). CONCLUSIONS AND RELEVANCE Among 6-year-old children in Guangzhou, China, the addition of 40 minutes of outdoor activity at school compared with usual activity resulted in a reduced incidence rate ofmyopia over the next 3 years. Further studies are needed to assess long-term follow-up of these children and the generalizability of these findings. Copyright 2015 American Medical Association. All rights reserved. Source
McEvoy M.,Hunter Medical Research Institute |
Schofield P.,University of Newcastle |
Smith W.,Environmental Health Branch |
Agho K.,University of Western Sydney |
And 4 more authors.
Current Alzheimer Research
Background: This study measured serum concentrations of vascular risk factors, asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) in a representative sample of older community-dwelling adults and determined their associations with objective and subjective memory impairment. Methods: Data on clinical, lifestyle, and demographic characteristics, serum ADMA, SDMA, and L-arginine (measured using LC-MS/MS) were collected from a population-based sample of older Australian adults from the Hunter Community Study. Objective memory was measured with the Audio Recorded Cognitive Screen (ARCS) neuropsychological battery and subjective memory impairment was measured using the Memory Complaint Questionnaire (MAC-Q). Results: Multivariate analysis revealed that SDMA and diabetes were significantly associated with objective memory impairment (Adjusted Odd ratio (AOR) = 3.90; 95% CI. 1.21 - 12.52 for fourth quartile (Q4) of SDMA. ADMA, SDMA, education, number of general practitioner visits and atrial fibrillation were all significantly associated with subjective memory impairment. (AOR = 1.82; 95% CI. 1.04 - 3.18 for Q4 ADMA. Conclusions: Higher serum SDMA was associated with objective and subjective memory impairment while higher serum ADMA was associated with subjective memory impairment. © 2014 Bentham Science Publishers. Source
Vaneckova P.,Queensland University of Technology |
Neville G.,Environmental Health Branch |
Tippett V.,Australian Center for Prehospital Research |
Aitken P.,James Cook University |
And 2 more authors.
Journal of Applied Meteorology and Climatology
Various biometeorological indices and temperature measures have been used to assess heat-related health risks. Composite indices are expected to assess human comfort more accurately than do temperature measures alone. The performances of several common biometeorological indices and temperature measures in evaluating the heat-related mortality in Brisbane, Australia-a city with a subtropical climate-were compared. Daily counts of deaths from organic causes [International Statistical Classification of Diseases and Related Health Problems, 9th Revision, (ICD9) codes 001-799 and ICD, 10th Revision, (ICD10) codes A00-R99] during the period from 1 January 1996 to 30 November 2004 were used. Several composite biometeorological indices were considered, such as apparent temperature, relative strain index, Thomdiscomfort index, the humidex, and wetbulb globe temperature. Hot days were defined as those days falling into the 95th percentile of each thermal stress indicator. Case-crossover analysis was applied to estimate the relationship between exposure to heat and mortality. The performances of various biometeorological indices and temperature measures were compared using the jackknife resamplingmethod. The results show that more deaths were likely to occur on hot days than on other (i.e., control) days regardless of the temperature measure or biometeorological index that is considered. The magnitude of the odds ratios varied with temperature indicators, between 1.08 [95% confidence interval (CI): 1.02-1.14] and 1.41 (95%CI: 1.22-1.64) after adjusting for air pollutants (particulate matter with aerodynamic diameter less than 10 μm and ozone).Average temperature performed similarly to the composite indices, but minimum and maximum temperatures performed relatively poorer. Thus, average temperature may be suitable for the development of weather-health warning systems if the findings presented herein are confirmed in different locations. © 2011 American Meteorological Society. Source