The aim was to examine a possible association of amount of sunshine and risk for acute closed angle glaucoma.
This was a retrospective analysis of hospital discharge registry data, linked to meteorological data for the same period.
The study was a national survey using hospital discharge data for the whole of Finland over a 10 year period.
All subjects with the acute closed angle glaucoma diagnosis from the hospital discharge registry were collected for the years 1972 to 1982. A total of 1796 patients were found.
Meteorological data from two cities in Finland, Helsinki and Oulu, were collected for the same years from the Finnish Meteorological Institute. A peak incidence of acute closed angle glaucoma was noted whenever the number of hours without sunshine increased. A regression analysis including incidence of acute closed angle glaucoma as a dependent variable, and sex, mean temperature, mean air pressure, mean humidity, total amount of rain per month, and mean sunshine hours as independent variables, was constructed. Sex and sunshine hours best explained the variation in incidence in a covariate model. No other meteorological variate could improve the model fit.
The result confirms that the number of hours without sunshine is positively associated with the incidence of acute closed angle glaucoma, when other meteorological variables are controlled for.
Although increases in inhalable particle (PM10) concentrations have been associated with acute reductions in the level of lung function and increased symptom reporting in children, including children with asthma, it is not clear whether these effects occur largely in asthmatic children, or even whether asthmatic children are more likely to experience these effects than children without asthma. To address these points, the following subgroups of children were selected from a survey population of all 2,200 elementary school children (6 to 13 yr of age) in a pulp mill community on the west coast of Vancouver Island: (1) all children with physician-diagnosed asthma (n = 75 participated), (2) all children with an exercise-induced fall in FEV1 without diagnosed asthma (n = 57), (3) all children with airway obstruction (FEV1/FVC
Despite substantial progress in modern preventive and clinical cardiology, acute myocardial infarction (AMI) remains a central acute cardiac event. The aim of this study was to check the basic daily environmental-physical conditions accompanying the occurrence of AMIs in a specific geographic area: Baku, Azerbaijan.
AMIs registered in the Baku area by 21 first-aid stations (n=4919) during 2003-2005 were compared with daily geomagnetic activity (GMA) levels (I(0)-IV(0)) and cosmic ray activity (CRA), described by neutron (imp/min) and solar activity. The same comparison was made for pre-admission fatal AMIs (n=440). The cosmophysical data came from space science centers in the USA, Russia, and Finland.
AMI morbidity followed a daily distribution according to GMA, mostly on quiet (I(0)) GMA days. A monthly comparison showed inverse relationships with solar activity and GMA and correlation with CRA. The daily clinical parameters of AMI correlated with CRA. Despite the daily rise in AMI mortality on days with the highest GMA, the days with the lowest GMA and higher CRA were predominant for AMI occurrence and pre-admission mortality. One of the possible predisposing factors can be life-threatening arrhythmia.
The monthly number of AMIs was inversely related to monthly solar activity and correlated with CRA-neutron activity. Pre-admission AMI mortality was inversely linked with GMA. Daily AMI pre-admission mortality rose with concomitant GMA; low-GMA and higher-neutron-activity AMIs occurred much more frequently and were more strongly related to the number of fatal pre-admission AMIs. The clinical course of AMI was linked with CRA level.
Erratum In: Med Sci Monit. 2007 Oct;13(10):LE16Babyev, Elchin [corrected to Babayev, Elchin]
Type 2 diabetes (T2D) and impaired glucose tolerance (IGT), historically extremely rare in children, is becoming prevalent among First Nations children. In Canada, many of these children live in remote villages accessible only by float plane. Because T2D has many long-term health implications, prevention and early identification are critical.
We developed a process for sending a fully equipped endocrinology team to a remote community to screen the children for T2D and IGT. Float plane (sea plane) travel has several unexpected limitations for a medical research team. These include having to travel in good visibility (visual flight rules), limited payload capacity, and restriction against transporting dry ice. The benefits include avoiding the usual security restrictions.
We developed and tested a custom-built insulation jacket and system of backup battery packs for the countertop -25 degrees C freezer (in lieu of dry ice) to transport frozen blood samples from the village to our hospital's laboratory. We also ensured that the five-member research team, its equipment, and the consumable supplies stayed within the maximum takeoff weight of the airplane and met center-of-gravity criteria to ensure a safe flight.
Using the insulated freezer, sample integrity was maintained throughout the flight, and a safe weight-and-balance trip was achieved for the team and supplies. The team obtained complete T2D screening data on 88% of children in the remote community.
Epidemiological studies have demonstrated associations between short-term increases in outdoor air pollution concentrations and adverse cardiovascular effects, including cardiac mortality and hospitalizations. One possible mechanism behind this association is that air pollution exposure increases the risk of developing a cardiac arrhythmia. To investigate this hypothesis, dates of implantable cardioverter defibrillator (ICD) discharges were abstracted from patient records in patients attending the two ICD clinics in Vancouver, BC, for the years 1997-2000. Daily outdoor air pollutant concentrations and daily meteorological data from the Vancouver region were obtained for the same 4-yr period. Generalized estimating equations were used to assess the association between short-term increases in air pollutant concentrations and ICD discharges while controlling for temporal trends, meteorology, and serial correlation in the data. Air pollution concentrations in the Vancouver region were relatively low from 1997 to 2000, as expected. In the 50 patients who resided within the Vancouver region and who experienced at least 1 ICD discharge during the period of follow-up, no significant associations between increased air pollution concentrations and increased ICD discharges were present. When the patient sample was restricted to the 16 patients who had at least 6 months of follow-up and experienced a rate of at least 2 days with ICD discharges per year, there was a statistically significant association between increased sulfur dioxide (SO(2)) concentration and ICD discharge 2 days after the SO(2) increase. When stratified by season, no associations between increased air pollutant concentrations and increased risk of ICD discharge were observed in the summer, although for several pollutants, concentration increases were associated with a decrease in ICD discharges. In the winter, increased SO(2) concentrations again were seen to be associated with increased risk of ICD discharge, at both 2 and 3 days following increases in SO(2) concentrations. These findings provide no compelling evidence that short-term increases in relatively low concentrations of outdoor air pollutants have an adverse effect on individuals at risk of cardiac arrhythmias. The findings regarding SO(2) are difficult to interpret. They may be chance findings. Alternatively, given the very low concentrations of SO(2) that were present in Vancouver, SO(2) may have been serving as a surrogate measure of other environmental or meteorological factors.
To investigate the potential correlation between ambient air pollution exposure and emergency department (ED) visits for depression.
A hierarchical clusters design was used to study 27 047 ED visits for depression in six cities in Canada. The data used in the analysis contain the dates of visits, daily numbers of diagnosed visits, and daily mean concentrations of air pollutants as well as the meteorological factors. The generalized linear mixed models technique was applied to data analysis. Poisson models were fitted to the clustered counts of ED visits with a single air pollutant, temperature and relative humidity.
Statistically significant positive correlations were observed between the number of ED visits for depression and the air concentrations of carbon monoxide (CO), nitrogen dioxide (NO2), sulphur dioxide (SO2) and particulate matter (PM10). The percentage increase in daily ED visits was 15.5% (95% CI: 8.0-23.5) for CO per 0.8 ppm and 20.0% (95% CI: 13.3-27.2) for NO2 per 20.1 ppb, for same day exposure in the warm weather period (April-September). For PM10, the largest increase, 7.2% (95% CI: 3.0-11.6) per 19.4 ug/m3, was observed for the cold weather period (October-March).
The results support the hypothesis that ED visits for depressive disorder correlate with ambient air pollution, and that a large majority of this pollution results from combustion of fossil fuels (e.g. in motor vehicles).
The concentration-response relationship between daily ambient inhalable particle (particulate matter less than or equal to 10 micro m; PM(10)) concentrations and daily mortality typically shows no evidence of a threshold concentration below which no relationship is observed. However, the power to assess a relationship at very low concentrations of PM(10) has been limited in studies to date. The concentrations of PM(10) and other air pollutants in Vancouver, British Columbia, Canada, from January 1994 through December 1996 were very low: the 50th and 90th percentiles of daily average PM(10) concentrations were 13 and 23 micro g/m(3), respectively, and 27 and 39 ppb, respectively, for 1-hr maximum ozone. Analyses of 3 years of daily pollution (PM(10), ozone, sulfur dioxide, nitrogen dioxide, and carbon monoxide) concentrations and mortality counts showed that the dominant associations were between ozone and total mortality and respiratory and cardiovascular mortality in the summer, and between nitrogen dioxide and total mortality in the winter, although some association with PM(10) may also have been present. We conclude that increases in low concentrations of air pollution are associated with increased daily mortality. These findings may support the notion that no threshold pollutant concentrations are present, but they also raise concern that these effects may not be effects of the measured pollutants themselves, but rather of some other factor(s) present in the air pollution-meteorology mix.
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Population structure, spatial diffusion, and climatic conditions mediate the spatiotemporal spread of seasonal influenza in temperate regions. However, much of our knowledge of these dynamics stems from a few well-studied countries, such as the United States (US), and the extent to which this applies in different demographic and climatic environments is not fully understood. Using novel data from Norway, Sweden, and Denmark, we applied wavelet analysis and non-parametric spatial statistics to explore the spatiotemporal dynamics of influenza transmission at regional and international scales. We found the timing and amplitude of epidemics were highly synchronized both within and between countries, despite the geographical isolation of many areas in our study. Within Norway, this synchrony was most strongly modulated by population size, confirming previous findings that hierarchical spread between larger populations underlies seasonal influenza dynamics at regional levels. However, we found no such association when comparing across countries, suggesting that other factors become important at the international scale. Finally, to frame our results within a wider global context, we compared our findings from Norway to those from the US. After correcting for differences in geographic scale, we unexpectedly found higher levels of synchrony in Norway, despite its smaller population size. We hypothesize that this greater synchrony may be driven by more favorable and spatially uniform climatic conditions, although there are other likely factors we were unable to consider (such as reduced variation in school term times and differences in population movements). Overall, our results highlight the importance of comparing influenza spread at different spatial scales and across diverse geographic regions in order to better understand the complex mechanisms underlying disease dynamics.