Biomedical subjects

Lothar Kreienbrock

Publications and source records attributed to Lothar Kreienbrock.

11 recordsLinked to original sources

PubMed2005

Increased lung cancer risk due to residential radon in a pooled and extended analysis of studies in Germany.

Residential radon has been shown to be a risk factor for lung cancer in several studies-but with limited power in each single study. The data of two case-control studies performed during 1990-1997 in Germany and used for previous publications have been extended and pooled. Both studies have identical study designs. In total, data of 2,963 incident lung cancer cases and 4,232 population controls are analyzed here. One-year radon measurements were performed in houses occupied during the 5-35 y prior to the interview. Conditional logistic and linear relative risk regression was used for the analysis. Measurements covered on average 70% of the exposure time window, with an average radon exposure of 61 Bq m(-3). The smoking and asbestos-adjusted ORs were 0.97 [95% confidence interval (CI) 0.85 to 1.11] for 50-80 Bq m(-3), 1.06 (95% CI 0.87 to 1.30) for 80-140 Bq m(-3) and 1.40 (95% CI 1.03 to 1.89) for radon concentrations above 140 Bq m(-3), compared to the reference category <50 Bq m(-3). The linear increase in the odds ratio per 100 Bq m(-3) was 0.10 (95% CI -0.02 to 0.30) for all subjects and 0.14 (95% CI -0.03 to 0.55) for less mobile subjects who lived in only one home in the last 5-35 y. The risk coefficients generally were higher when measurement error in the radon concentrations was reduced by restricting the population. With respect to histopathology, the risk for small cell carcinoma was higher than for other subtypes. This analysis strengthens the evidence that residential radon is a relevant risk factor for lung cancer.

Adult↗

PubMed2003

Hormonal factors and risk of lung cancer among women?

BACKGROUND: Gender differences in the histological distribution of lung carcinoma and a possibly greater susceptibility of women than men to tobacco carcinogens, suggest a possible influence of sex-specific hormones. This study examines endocrine factors and risk of lung cancer among women by smoking status and histology. METHODS: We used data of a case-control study on lung cancer conducted from 1990 to 1996 in Germany, including 811 histologically confirmed female cases and 912 female population controls. Information on various menstrual and reproductive factors, use of oral contraceptives (OC), hormone replacement therapy (HRT), and smoking was gathered through personal interviews using a structured questionnaire. Odds ratios (OR) and 95% CI adjusted for age, region, smoking, and education were calculated via logistic regression. RESULTS: A reduction in lung cancer risk was observed with the use of OC (OR = 0.69; 95% CI: 0.51-0.92), but no trend in risk with increasing duration of use, age at first use, or calendar year of first use was present. A history of HRT was associated with a reduced risk (OR = 0.83; 95% CI: 0.64-1.09), particularly after long duration (>/=7 years) (OR = 0.59; 95% CI: 0.37-0.93). No clear association was found with regard to age at menarche, length of menstrual cycle, number of live-births, and age at menopause. Overall results did not differ much by histological cell subtype. The reduction in lung cancer risk associated with the use of exogenous hormones was primarily seen among smoking women. CONCLUSIONS: Our data provide evidence for a possible role of hormonal factors in the aetiology of lung cancer in women.

Adult↗

PubMed2003

Residential radon and risk of lung cancer in Eastern Germany.

BACKGROUND: There is suggestive evidence that residential radon increases lung cancer risk. To elucidate this association further, we conducted a case-control study in Thuringia and Saxony in Eastern Germany during 1990-1997. METHODS: Histologically confirmed lung cancer patients from hospitals and a random sample of population controls matched on age, sex and geographical area were personally interviewed with respect to residential history, smoking, and other risk factors. One-year radon measurements were performed in houses occupied during the 5-35 years prior to the interview. The final analysis included a total of 1,192 cases and 1,640 controls. Odds ratios (OR) and 95% confidence intervals (CI) were estimated by logistic regression. RESULTS: Measurements covered on average 72% of the exposure time window, with mean radon concentrations of 76 Bq/m3 among the cases and 74 Bq/m3 among the controls. The smoking- and asbestos-adjusted ORs for categories of radon (50-80, 80-140 and >140 Bq/m*3, compared with 0-50 Bq/m3) were 0.95 (CI = 0.77 to 1.18), 1.13 (CI = 0.86 to1.50) and 1.30 (CI = 0.88 to 1.93). The excess relative risk per 100 Bq/mł was 0.08 (CI = -0.03 to 0.20) for all subjects and 0.09 (CI = -0.06 to 0.27) for subjects with complete measurements for all 30 years. CONCLUSIONS: Our data indicate a small increase in lung cancer risk as a result of residential radon that is consistent with the findings of previous indoor radon and miner studies.

Aged↗

PubMed2002

Risk factors for lung cancer among nonsmoking women.

To evaluate risk factors for lung cancer in nonsmoking women, we used data of a case-control study conducted between 1991 and 1996 in Germany. A total of 234 female histologically confirmed lung cancer patients and 535 population controls who had never smoked more than 400 cigarettes in their lifetime were personally interviewed with respect to occupation, exposure to environmental tobacco smoke (ETS), family history of cancer, prior physician-diagnosed lung diseases or cancer and diet. One-year radon measurements in the last dwelling were performed. Odds ratios (OR) adjusted for age and region and 95% confidence intervals (CI) were calculated via logistic regression. When cumulative duration of exposure to ETS in hours was considered, the OR for high compared to not or low ETS exposed women was 2.62 (CI:1.35-5.06) for occupational exposure and OR=1.67 (CI:0.86-3.25) for spousal exposure, exhibiting a significant trend for ETS at work. Working more than 10 years in jobs or industries with known or suspected lung carcinogens was associated with OR=2.0 (CI:0.99-4.0). An elevated risk due to prior lung diseases was present for pneumonia (OR=1.6; CI:1.07-2.40) and tuberculosis (OR=1.6; CI:0.77-3.37). No significant increase in risk with increasing residential radon levels or with the presence of a family history of lung cancer was apparent. Protective effects were observed for high vs. low consumption of fresh vegetables (OR=0.5; CI:0.25-0.82) and cheese (OR=0.3, CI:0.21-0.55). ETS at work, occupational hazards and previous pneumonia may be risk factors for lung cancer in nonsmoking women, while a diet rich in fresh vegetables and cheese seems to be protective.

Aged↗

PubMed2002

Calculating sample size bounds for logistic regression.

The calculation of a study's required sample size is one of the most important aspects of the validity of an epidemiological study. Logistic regression often is used in modelling in epidemiology. A simplified method to calculate the sample size for the multiple logistic-regression model was proposed by Hsieh et al. [Stat. Med. 17 (1998) 1623]. The approach for estimating the sample size is described and then applied in the planning of an epidemiological cross-sectional study of the associations of different risk factors with Toxoplasma infection among pregnant women. Although the method demands some additional information which is often difficult to obtain, it is a very useful tool in veterinary epidemiology.

Animals↗

PubMedDate not supplied

[The occurrence of Echinococcus multilocularis in red foxes in lower Saxony: identification of a high risk area by spatial epidemiological cluster analysis].

There is considerable interest in the spatial distribution of Echinococcus multilocularis in red foxes (Vulpes vulpes L.), because this parasite causes the zoonoses of alveolar echinococcosis which is potentially of high fatality rate. High risk areas are known from France, Switzerland and the Swabian Alb in Germany for a long time. In this work, the spatial scan statistic is introduced as an instrument for identification and localisation of high risk areas, so called disease clusters in spatial epidemiology. The use of the spatial scan statistic along with data about the distribution of the parasite in 5365 red foxes in Lower Saxony, that were collected during 1991 to 1997, led to the identification of another high risk area. The relative risk for this disease cluster is approximated by RR = 5.03 (CI0.95(RR) = [4.27; 6.58]) for the period of 1991 to 1994 and by RR = 4.45 (CI0.95(RR) = [3.53; 5.59]) for the period of 1994 to 1997, respectively.

Animals↗

PubMedDate not supplied

["Risk analysis"].

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Animals↗

PubMedDate not supplied

[The use of macrolides, lincomycin and tiamulin as animal feed drugs for pigs in Schleswig-Holstein].

An evaluation of production orders for medicated feedingstuffs for pigs given in 1998 in Schleswig-Holstein showed macrolides, lincomycin and tiamulin as frequently used antibiotical ingredients. The presented study analyses the production orders which include macrolides, lincomycin or tiamulin in more detail. There were large deviations to the rules of good clinical practise for the use of antibiotics (2000). The applied dosage was often lower than suggested in the literature.

Animal Feed↗

PubMedDate not supplied

[The use of sulfonamides and sulfonamide/trimethoprim combinations as animal feed drugs for pigs in Schleswig-Holstein].

An evaluation of production orders for medicated feedingstuffs for pigs given in 1998 in Schleswig-Holstein showed sulphonamides and combinations of sulphonamides and trimethoprim as frequently used antibiotical ingredients. The presented study analyses the production orders which include sulphonamides and combinations of sulphonamides and trimethoprim in more detail. There were large deviations to the rules of good clinical practise for the use of antibiotics. The applied dosage was often lower than suggested in the literature.

Animal Feed↗

PubMedDate not supplied

[The use of aminoglycosides, colistin and beta-lactam antibiotics as animal feed drugs for pigs in Schleswig-Holstein].

An evaluation of production orders for medicated feedingstuffs for pigs given in 1998 in Schleswig-Holstein showed aminoglycosides, colistin and beta-lactam antibiotics as regularly used antibiotical ingredients. The presented study analyses the production orders which include these antibiotics more in detail particularly with regard to the prescribed dosages. In part, there were deviations to the rules of good clinical practise for the use of anitbiotics. The applied dosage of spectinomycin and apramycin was often lower than suggested in the literature. The low oral bioavailability of amoxicillin was not considered when using amoxicillin in medicated feedingstuffs.

Aminoglycosides↗

PubMedDate not supplied

[The effect of response behaviour on veterinary epidemiological studies--an analysis based on a cross-sectional study of livestock management of cattle farms in Lower Saxony].

Cross-sectional studies are used as an epidemiological instrument in several veterinary investigations. A common means of collecting information is the questionnaire, which is send to diagnostic units like farmers. A common fact is, that not all designated individuals take part. So it is to be clarified, if and in which concern this fact influences the results of an epidemiological study. Considering the example of a cross-sectional study in cattle farms this paper shows, that consistency of Responders and Non-Responders differs significantly. Technical measures to estimate this effect and consequences for the results are shown. Small and medium farms showed a different response rate than big farms before as well as after a mailed reminding letter. Considering the complete return period there was no significantly different response rate between farms of different sizes. Furthermore there are noticeable differences between Responders and Non-Responders concerning parameters like housing or use of commercial feedstuff. Therefore it is implicitly required to send a reminding letter and pursue Non-Responders in researches. Otherwise a biased sample collective is generated.

Agriculture↗