We examined the role that ambient air pollution plays in exacerbating cardiac disease by relating daily fluctuations in admissions to 134 hospitals for congestive heart failure in the elderly to daily variations in ambient concentrations of carbon monoxide, nitrogen dioxide, sulfur dioxide, ozone, and the coefficient of haze in Canada's 10 largest cities for the 11-year period 1981-1991 inclusive. We adjusted the hospitalization time series for seasonal, subseasonal, and weekly cycles and for hospital usage patterns. The logarithm of the daily high-hour ambient carbon monoxide concentration recorded on the day of admission displayed the strongest and most consistent association with hospitalization rates among the pollutants, after stratifying the time series by month of year and adjusting simultaneously for temperature, dew point, and the other ambient air pollutants. The relative risk for a change from 1 ppm to 3 ppm, the 25th and 75th percentiles of the exposure distribution, was 1.065 (95% confidence interval = 1.028-1.104). The regression coefficients of the other air pollutants were much more sensitive to simultaneous adjustment for either multiple pollutant or weather model specifications.
The effects of tropospheric ozone on lung function and respiratory symptoms have been well documented at relatively high concentrations. However, previous investigations have failed to establish a clear association between tropospheric ozone and respiratory diseases severe enough to require hospitalization after controlling for climate, and with gaseous and particulate air pollution at the lower concentrations typically observed in Canada today. To determine if low levels of tropospheric ozone contribute to hospitalization for respiratory disease, air pollution data were compared to hospital admissions for 16 cities across Canada representing 12.6 million people. During the 3927-day period from April 1, 1981, to December 31, 1991, there were 720,519 admissions for which the principle diagnosis was a respiratory disease. After controlling for sulfur dioxide, nitrogen dioxide, carbon monoxide, soiling index, and dew point temperature, the daily high hour concentration of ozone recorded 1 day previous to the date of admission was positively associated with respiratory admissions in the April to December period but not in the winter months. The relative risk for a 30 ppb increase in ozone varied from 1.043 (P
The present study investigated the association between 24-h urinary sodium excretion and heart rate in the determination of blood pressure (BP) levels in a large random population sample from eastern Finland. Three independent risk factor surveys were performed in 1979, 1982 and 1987 using the same methodology. Data from each survey was pooled for subjects aged 25-64 years who reported a complete 24-h urine collection and were not on the current antihypertensive treatment (1640 men and 1686 women). The effect of urinary sodium excretion and heart rate was examined by regressing BP on urinary sodium excretion and pulse rate, together with age and body mass index (BMI). Analyses stratified by quintiles of heart rate were also performed. There was no association between urinary sodium and BP either in men or in women. There was a significant correlation between heart rate and both systolic and diastolic BP in both men and women. A significant interaction between age and BMI with heart rate was also found in both sexes. Interaction between urinary sodium and heart rate was found neither in men nor in women. Among men, after adjustment for age and BMI, there was a curvilinear relation between 24-h urinary excretion of sodium and diastolic BP (P = 0.054) in the lowest quintile of heart rate (
The association of daily cardiac and respiratory admissions to 168 acute care hospitals in Ontario, Canada, with daily levels of particulate sulfates was examined over the 6-year period 1983-1988. Sulfate levels were recorded at nine monitoring stations in regions of southern and central Ontario spanned by three monitoring networks. A 13-micrograms/m3 increase in sulfates recorded on the day prior to admission (the 95th percentile) was associated with a 3.7% (p
A case-control study of lung cancer in relation to exposure to radon in homes in Winnipeg, Manitoba, Canada, was conducted during 1983-1990. In total, 738 individuals with histologically confirmed incident cases of lung cancer were interviewed, along with 738 controls matched on age (+/- 5 years) and sex. Radon dosimeters were placed in all residences in which the study subjects had reported living within the Winnipeg metropolitan area for at least 1 year. Radon dosimetry was done by means of integrated alpha-track measurements over a 1-year period. In the homes monitored, the average level of radon-222 was about 120 becquerels (Bq)/m3 in the bedroom area and 200 Bq/m3 in the basement. After adjusting for cigarette smoking and education, no increase in the relative risk for any of the histologic types of lung cancer observed among the cases was detected in relation to cumulative exposure to radon.
Comment In: Am J Epidemiol. 1995 Nov 15;142(10):1121-27485057
Comment In: Am J Epidemiol. 1995 Oct 15;142(8):884-67572965
Comment In: Am J Epidemiol. 1994 Aug 15;140(4):323-328059767
Comment In: Am J Epidemiol. 1994 Aug 15;140(4):333-98059768
We studied the association of glucose intolerance with total and cause-specific mortality during a 5-year follow-up of 637 elderly Finnish men aged 65 to 84 years. Total mortality was 276 per 1000 for men aged 65 to 74 years and 537 per 1000 for men aged 75 to 84 years. Five-year total mortality adjusted for age was 364 per 1000 in diabetic men, 234 per 1000 in men with impaired glucose tolerance and 209 per 1000 in men with normal glucose tolerance. The relative risk of death among diabetic men was 2.10 (95% confidence interval 1.26 to 3.49) and among men with impaired glucose tolerance 1.17 (95% confidence interval 0.71 to 1.94) times higher compared with men with normal glucose tolerance. Cardiovascular disease was the most common cause of death in every glucose tolerance group. The multivariate adjusted relative risk of cardiovascular death was increased (1.55) in diabetic patients, albeit non-significantly (95% confidence interval 0.84 to 2.85). Diabetes resulted in an increased risk of cardiovascular mortality among men aged 65-74 years but not among the 75- 84-year-old men. Relative risk of death from non-cardiovascular causes was slightly increased among diabetic subjects. In conclusion, diabetes mellitus is a significant determinant of mortality among elderly Finnish men.
To investigate the role of diet as a predictor of glucose intolerance and non-insulin-dependent diabetes mellitus (NIDDM).
At the 30-year follow-up survey of the Dutch and Finnish cohorts of the Seven Countries Study, in 1989/1990, men were examined according to a standardized protocol including a 2-h oral glucose tolerance test. Information on habitual food consumption was obtained using the cross-check dietary history method. Those 338 men in whom information on habitual diet was also available 20 years earlier were included in this study. Subjects known as having diabetes in 1989/1990 were excluded from the analyses.
Adjusting for age and cohort, the intake of total, saturated, and monounsaturated fatty acids and dietary cholesterol 20 years before diagnosis was higher in men with newly diagnosed diabetes in the survey than in men with normal or impaired glucose tolerance. After adjustment for cohort, age, past body mass index, and past energy intake, the past intake of total fat was positively associated with 2-h postload glucose level (P
Assess associations between short-term exposure to gaseous pollutants and asthma hospitalisation among boys and girls 6 to12 years of age.
A bi-directional case-crossover analysis was used. Conditional logistic regression models were fitted to the data for boys and girls separately. Exposures averaged over periods ranging from one to seven days were used to assess the effects of gaseous pollutants on asthma hospitalisation. Estimated relative risks for asthma hospitalisation were calculated for an incremental exposure corresponding to the interquartile range in pollutant levels, adjusted for daily weather conditions and concomitant exposure to particulate matter.
Toronto, Ontario, Canada.
A total of 7319 asthma hospitalisations for children 6 to 12 years of age (4629 for boys and 2690 for girls) in Toronto between 1981 and 1993.
A significant acute effect of carbon monoxide on asthma hospitalisation was found in boys, and sulphur dioxide showed significant effects of prolonged exposure in girls. Nitrogen dioxide was positively associated with asthma admissions in both sexes. The lag time for certain gaseous pollutant effects seemed to be shorter in boys (around two to three days for carbon monoxide and nitrogen dioxide), as compared with girls (about six to seven days for sulphur dioxide and nitrogen dioxide). The effects of gaseous pollutants on asthma hospitalisation remained after adjustment of particulate matter. The data showed no association between ozone and asthma hospitalisation in children.
The study showed positive relations between gaseous pollutants (carbon monoxide, sulphur dioxide, and nitrogen dioxide) at comparatively low levels and asthma hospitalisation in children, using bi-directional case-crossover analyses. Though, the effects of certain specific gaseous pollutants were found to vary in boys and girls.
Cites: Environ Res. 1994 Oct;67(1):1-197925191
Cites: Environ Res. 1994 Apr;65(1):56-688162885
Cites: N Engl J Med. 1995 Jan 19;332(3):133-87800004
Cites: Environ Health Perspect. 1995 Mar;103 Suppl 2:97-1027614954
Cites: Epidemiology. 1995 Sep;6(5):476-848562622
Cites: Thorax. 1995 Oct;50(10):1051-67491552
Cites: Thorax. 1995 Sep;50(9):948-548539674
Cites: Thorax. 1995 Nov;50(11):1188-938553276
Cites: Thorax. 1996 Jan;51 Suppl 1:S3-68658385
Cites: Thorax. 1996 Jan;51(1):13-228658362
Cites: J Epidemiol Community Health. 1996 Apr;50 Suppl 1:S3-118758217
Cites: J Epidemiol Community Health. 1996 Apr;50 Suppl 1:s22-98758220
Cites: J Epidemiol Community Health. 1996 Apr;50 Suppl 1:s42-68758223
Cites: J Epidemiol Community Health. 1996 Apr;50 Suppl 1:s63-708758227
Cites: J Epidemiol Community Health. 1996 Apr;50 Suppl 1:s71-58758228
Cites: Environ Health Perspect. 1996 Dec;104(12):1354-609118879
Cites: Environ Health Perspect. 1997 Feb;105(2):216-229105797
Cites: Epidemiology. 1997 Mar;8(2):162-79229208
Cites: Thorax. 1997 Sep;52(9):760-59371204
Cites: J Expo Anal Environ Epidemiol. 1998 Apr-Jun;8(2):129-449577746
Cites: Biometrics. 1998 Jun;54(2):596-6059629646
Cites: J Air Waste Manag Assoc. 1998 Aug;48(8):689-7009739623
Cites: Am J Public Health. 1998 Dec;88(12):1761-69842371
Cites: Epidemiology. 1999 Jan;10(1):23-309888276
Cites: Health Rep. 1998 Winter;10(3):9-21 (ENG); 9-22 (FRE)9926344
Cites: Arch Environ Health. 1999 Mar-Apr;54(2):130-910094292
Cites: Environ Health Perspect. 1999 Jun;107(6):489-9310339450
Cites: Environ Health Perspect. 1999 Jun;107 Suppl 3:421-910423388
Cites: Environ Health Perspect. 1999 Aug;107(8):629-3110417359
Cites: Environ Health Perspect. 1999 Aug;107(8):633-610417360
To investigate the acute respiratory health effects of ambient air pollution, the number of emergency of urgent daily respiratory admissions to 168 acute care hospitals in Ontario were related to estimates of exposure to ozone and sulfates in the vicinity of each hospital. Ozone levels were obtained from 22 monitoring stations maintained by the Ontario Ministry of the Environment for the period January 1, 1983 to December 31, 1988. Daily levels of sulfates were recorded at nine monitoring stations representing three different networks operated by the Ontario Ministry of the Environment and Environment Canada. Positive and statistically significant associations were found between hospital admissions and both ozone and sulfates recorded on the day of admission and up to 3 days prior to the date of admission. Five percent of daily respiratory admissions in the months of May to August were associated with ozone, with sulfates accounting for an additional 1% of these admissions. Ozone was a stronger predictor of admissions than sulfates. Positive and statistically significant (P