Search PubMed⌕ Search

Biomedical subjects

Juha Pekkanen

Publications and source records attributed to Juha Pekkanen.

10 recordsLinked to original sources
PubMed2003

Effect of acute carbon monoxide exposure on heart rate variability in patients with coronary artery disease.

Epidemiological studies have shown that air pollution is associated with increased cardiovascular mortality. Although the pathophysiological mechanisms behind this association have remained largely unknown, it has been suggested that changes in cardiac autonomic function may play a role. In this study, we investigated the association between acute carbon monoxide (CO) exposure and cardiac autonomic function as measured by heart rate variability (HRV) in subjects with stable coronary artery disease. Twenty-four hour ambulatory electrocardiographic recording with simultaneous continuous personal CO concentration monitoring was performed in six male patients with angiographically verified coronary artery disease three times with 1-week intervals. Time domain measures of HRV were calculated for 5-min segments before and during the CO exposure periods. For further analysis CO exposures were divided into low (</=2.7 p.p.m.) and high (>2.7 p.p.m.) CO exposure periods. The mean of maximum CO levels during 61 CO exposure periods was 4.6 p.p.m. (SD 5.0 p.p.m.). High CO exposure was associated with an increase in the square root of the mean of the sum of the squares of differences between adjacent RR intervals (r-MSSD) (P = 0.034). Heart rate remained unchanged during the CO exposure. In conclusion, acute CO exposure which represented most likely exposure derived from traffic seems to modify cardiac autonomic control in patients with stable coronary artery disease.

Acute Disease↗
PubMed2002

Particulate air pollution and risk of ST-segment depression during repeated submaximal exercise tests among subjects with coronary heart disease: the Exposure and Risk Assessment for Fine and Ultrafine Particles in Ambient Air (ULTRA) study.

BACKGROUND: Daily variations in ambient particulate air pollution have been associated with cardiovascular mortality and morbidity. We therefore assessed the associations between levels of the 3 main modes of urban aerosol distribution and the occurrence of ST-segment depressions during repeated exercise tests. METHODS AND RESULTS: Repeated biweekly submaximal exercise tests were performed during 6 months among adult subjects with stable coronary heart disease in Helsinki, Finland. Seventy-two exercise-induced ST-segment depressions >0.1 mV occurred during 342 exercise tests among 45 subjects. Simultaneously, particle mass <2.5 microm (PM2.5) and the number concentrations of ultrafine particles (particle diameter 10 to 100 nm [NC(0.01-0.1)]) and accumulation mode particles (100 to 1000 nm [NC(0.1-1)]) were monitored at a central site. Levels of particulate air pollution 2 days before the clinic visit were significantly associated with increased risk of ST-segment depression during exercise test. The association was most consistent for measures of particles reflecting accumulation mode particles (odds ratio 3.29; 95% CI, 1.57 to 6.92 for NC(0.1-1) and 2.84; 95% CI, 1.42 to 5.66 for PM2.5), but ultrafine particles also had an effect (odds ratio 3.14; 95% CI, 1.56 to 6.32), which was independent of PM2.5. Also, gaseous pollutants NO2 and CO were associated with an increased risk for ST-segment depressions. No consistent association was observed for coarse particles. The associations tended to be stronger among subjects who did not use beta-blockers. CONCLUSIONS: The present results suggest that the effect of particulate air pollution on cardiovascular morbidity is at least partly mediated through increased susceptibility to myocardial ischemia.

Adult↗
PubMed2002

Hemostatic factors as predictors of coronary events and total mortality: The FINRISK '92 Hemostasis Study.

The role of hemostatic factors as predictors of coronary heart disease (CHD) and total mortality is poorly understood. Therefore, we carried out a prospective cohort study in Finland. In 1992, a random population sample of 2378 men and women aged 45 to 64 years was investigated and then followed up until December 31, 1998. During the follow-up, 133 CHD events were observed; 73 were among participants free of CHD at baseline. The total number of deaths was 124. After adjustment for traditional risk factors and prevalent CHD at baseline and correction for regression dilution bias, a 1-SD increase in plasminogen was associated with a 1.41-fold (95% CI 1.09 to 1.81) increase in CHD risk. The predictive power of plasminogen depended significantly on the level of total cholesterol being stronger for persons with high cholesterol. A 1-SD increase in fibrinogen was associated with a 1.23-fold (95% CI 1.05 to 1.44) increase in all-cause mortality, but its association with CHD events did not reach statistical significance. Factor VII antigen or coagulant activity or lipoprotein(a) were not independent predictors of CHD risk. These findings support the role of plasminogen as a risk factor for CHD events.

Antigens↗
PubMed2002

Uranium and other natural radionuclides in drinking water and risk of leukemia: a case-cohort study in Finland.

OBJECTIVE: We assessed the effect of natural uranium and other radionuclides in drinking water on risk of leukemia. METHODS: The subjects (n = 144,627) in the base cohort had lived outside the municipal tapwater system during 1967-1980. A subcohort was formed as a stratified random sample of the base cohort and subjects using drinking water from drilled wells prior to 1981 were identified. A case-cohort design was used comparing exposure among cases with leukemia (n = 35) with a stratified random sample (n = 274) from the subcohort. Activity concentrations of uranium, radium-226, and radon in the drinking water were analyzed using radiochemical and alpha-spectrometric methods. RESULTS: The median activity concentration of uranium in well water was 0.08 Bq/L for the leukemia cases and 0.06 Bq/L for the reference group, radon concentrations 80 and 130 Bq/L, respectively, and radium-226 concentrations 0.01 Bq/L for both groups. The hazard ratio of leukemia for uranium was 0.91 (95% confidence interval 0.73-1.13) per Bq/L. for radon 0.79 per Bq/L (95% CI 0.27-2.29), and for radium-226 0.80 (95% CI 0.46-1.39) per Bq/L. CONCLUSIONS: Our results do not indicate an increased risk of leukemia from ingestion of natural uranium or other radionuclides through drinking water at these exposure levels.

Aged↗
PubMed2002

Mould-specific immunoglobulin G antibodies in students from moisture- and mould-damaged schools: a 3-year follow-up study.

Immunoglobulin G (IgG) antibodies to moulds have been used as biomarkers of mould exposure, though their role reflecting exposure is not confirmed. The purpose of the present study was to evaluate the changes in mould-specific IgG antibodies in children during a 3-year follow-up in relation to changes in exposure, and to allergic and respiratory morbidity. In 1996, 212 primary school students with asthma, wheezing or prolonged cough participated in a clinical study, including clinical examination, skin-prick tests to 12 moulds and mould-specific IgG determinations to 24 moulds. In 1999, 144 students of the same cohort participated in an identical follow-up study; among them, mould-specific IgG was measured in 121 students. No association was found between IgG antibodies to moulds and exposure to moisture or moulds in schools. Likewise, changes in mould-specific antibodies were only weakly associated with changes in exposure. Mould-specific IgG antibodies had no significant association with asthma, wheezing or cough episodes. IgG antibodies to moulds seem to be poor markers of exposure among children exposed to moisture or moulds at school.

Adolescent↗
PubMed2002

Photometrically measured continuous personal PM(2.5) exposure: levels and correlation to a gravimetric method.

There is evidence that hourly variations in exposure to airborne particulate matter (PM) may be associated with adverse health effects. Still there are only few published data on short-term levels of personal exposure to PM in community settings. The objectives of the study were to assess hourly and shorter-term variations in personal PM(2.5) exposure in Helsinki, Finland, and to compare results from portable photometers to simultaneously measured gravimetric concentrations. The effect of relative humidity on the photometric results was also evaluated. Personal PM(2.5) exposures of elderly persons were assessed for 24 h every second week, resulting in 308 successful measurements from 47 different subjects. Large changes in concentrations in minutes after cooking or changing microenvironment were seen. The median of daily 1-h maxima was over twice the median of 24-h averages. There was a strong significant association between the two means, which was not linear. Median (95th percentile) of the photometric 24-h concentrations was 12.1 (37.7) and of the 24-h gravimetric concentrations 9.2 (21.3) microg/m3. The correlation between the photometric and the gravimetric method was quite good (R2=0.86). Participants spent 94.1% of their time indoors or in a vehicle, where relative humidity is usually low and thus not likely to cause significant effects on photometric results. Even outdoors, the relative humidity had only modest effect on concentrations. Photometers are a promising method to explore the health effects of short-term variation in personal PM(2.5) exposure.

Activities of Daily Living↗
PubMed2002

Allergic diseases, skin prick test responses, and IgE levels in North Karelia, Finland, and the Republic of Karelia, Russia.

BACKGROUND: There is growing evidence to show that atopic diseases are more common in Western Europe than in the former socialist countries of Eastern Europe. OBJECTIVE: The aim of this study was to assess whether a similar difference exists between the most eastern province of Finland and a neighboring western district of Russia. METHODS: A random sample of 25- to 54-year-old subjects was taken from the population registers in the North Karelia Province in eastern Finland and from the Pitkäranta district across the border in the western part of Russia. Participants filled out a questionnaire on atopic and allergic symptoms and participated in a clinical study, which included skin prick tests with 11 airborne allergens and IgE measurements. RESULTS: Self-reported hay fever, allergic eye symptoms, atopic eczema, and asthma were much more common in Finland than in Russia. In Finland 34.2% and in Russia 21.8% had at least one positive skin prick test reaction. In Finland 21.5% but in Russia only 15.8% had at least one elevated allergen-specific IgE value of the 5 values measured. From 6% to 47% of the differences in self-reported symptoms between the countries were explained by atopy, as measured by means of skin prick testing or specific IgE values. CONCLUSIONS: A major difference in clinical allergic diseases and signs of symptoms was observed between the 2 geographically adjacent areas. This suggests that the difference in clinical allergy and atopic disposition is related to the differences in lifestyle and environmental factors.

Adult↗
PubMed2002

Body build from birth to adulthood and risk of asthma.

BACKGROUND: Few reports aimed at the study of adulthood obesity and asthma have taken into account the effects of size at birth and obesity in adolescence. This paper examines the combined effect of size at birth and obesity in both adolescence and adulthood on the risk of asthma at age 31 years. METHODS: The study was derived from a prospectively population-based Finnish birth cohort born in 1966, for which data were collected in pregnancy and at various ages. Adulthood doctor-diagnosed asthma with current symptoms and results of skin prick tests were obtained in 1997. The analysis was limited to 4719 subjects with complete information on asthma and atopy and anthropometric measures at various ages. RESULTS: Ponderal index at birth had a U-shaped association with adult atopy, OR 1.30 (95% CI: 1.11-1.52) for the lowest tertile and OR 1.33 (95% CI: 1.13-1.55) for the highest tertile, as compared to the middle tertile. The association was independent of obesity later in life. Those obese (BMI > or = 95th percentile) in adolescence (OR 2.09, 95% CI: 1.23-3.57) and in adulthood (OR 1.99, 95% CI: 1.14-3.47) had a higher occurrence of adult asthma than those with BMI < 85th percentile. Both estimates were reduced after mutual adjustment. CONCLUSIONS: Size at birth has a long-lasting effect on atopy in adulthood, which is independent of weight in adolescence and adulthood. Those who were obese in adolescence and adulthood tended to have a higher risk of asthma in adulthood. These findings underline the importance of considering the life course of obesity in the analyses of asthma and atopy.

Adolescent↗
PubMed2002

Renal effects of uranium in drinking water.

Animal studies and small studies in humans have shown that uranium is nephrotoxic. However, more information about its renal effects in humans following chronic exposure through drinking water is required. We measured uranium concentrations in drinking water and urine in 325 persons who had used drilled wells for drinking water. We measured urine and serum concentrations of calcium, phosphate, glucose, albumin, creatinine, and beta-2-microglobulin to evaluate possible renal effects. The median uranium concentration in drinking water was 28 microg/L (interquartile range 6-135, max. 1,920 microg/L) and in urine 13 ng/mmol creatinine (2-75), resulting in the median daily uranium intake of 39 microg (7-224). Uranium concentration in urine was statistically significantly associated with increased fractional excretion of calcium and phosphate. Increase of uranium in urine by 1 microg/mmol creatinine increased fractional excretion of calcium by 1.5% [95% confidence interval (CI), 0.6-2.3], phosphate by 13% (1.4-25), and glucose excretion by 0.7 micromol/min (-0.4-1.8). Uranium concentrations in drinking water and daily intake of uranium were statistically significantly associated with calcium fractional excretion, but not with phosphate or glucose excretion. Uranium exposure was not associated with creatinine clearance or urinary albumin, which reflect glomerular function. In conclusion, uranium exposure is weakly associated with altered proximal tubulus function without a clear threshold, which suggests that even low uranium concentrations in drinking water can cause nephrotoxic effects. Despite chronic intake of water with high uranium concentration, we observed no effect on glomerular function. The clinical and public health relevance of the findings are not easily established, but our results suggest that the safe concentration of uranium in drinking water may be within the range of the proposed guideline values of 2-30 microg/L.

Adolescent↗