Most studies studying dampness as a risk factor for asthma are of a cross-sectional design. The aim of this study was to investigate if the association between moisture-related problems indoor and asthma found in cross-sectional questionnaire data can be confirmed in longitudinal analyses. The Dampness in Building and Health (DBH) study started in 2000 in Värmland, Sweden, with a baseline questionnaire to all children aged 1-5 y (n = 14,077) and five years later a follow-up questionnaire was distributed to children aged 6-8 y (n = 7,509). Moisture-related problems that were associated with asthma in cross-sectional analysis decreased or disappeared in the longitudinal analysis. However, the association between reports of moldy odor in the homes at baseline and incident asthma remained and became stronger. Our results suggest that cross-sectional data showing associations between moisture-related problems in homes and asthma in children partly can be explained by reporting bias.
Research has shown that hip fracture risk increases with latitude; hypothetically due to reduced sunlight exposure and its effect on bone quality. Sweden, with large differences in latitude and UV radiation, is ideal to study in order to analyse the association between latitude and UV radiation on age- and sex-specific hip fracture rates among elderly.
Aggregated (2006-2008) age- and sex-specific hip fracture data was obtained for each Swedish municipality as well as the municipality's latitudinal coordinates and aggregated (2006-2008) UV radiation levels. Pearson correlations were calculated between hip fracture incidence rates, latitude and UV radiation. Independent t tests were calculated on tertile-categorized latitudinal data in order to investigate the difference in hip fracture risk between these categories.
Statistically significant correlations were seen in all groups between hip fracture incidence rates and latitude as well as UV radiation. The independent t tests showed that this correlation was mainly due to high incidence rates in high latitude municipalities.
Statistically significant correlations are seen between hip fracture incidence rates and latitude as well as UV radiation in Sweden and the northern parts of Sweden have an increased risk of hip fractures compared to the middle and southern parts. To our knowledge this is the first study using a national discharge register that shows this relationship and provides a starting point for further research to investigate why populations in northern Sweden have a higher risk of hip fractures compared to other Swedish regions.
Fall-related injuries have been a cause of worry during the end of the 20th century with increasing trends among the elderly.
Using data from the Swedish National Patient Register (NPR) based on hospital admissions, this study explores the trends in fall-related fractures between 1998 and 2010.
The data shows a decreasing trend in fall-related fractures in all age- and sex-specific groups apart from men 80 years and above. While hip fracture incidence rates decreased in all age- and sex-specific groups, both central fractures and upper extremity fractures have increased in all age- and sex-specific groups apart from women 65-79 years. Lower extremity fractures have increased in the older age groups and decreased in the younger.
The differences found between the groups of fractures and by age- and sex-specific groups indicate a possible transition where more serious fractures are decreasing while less serious fractures increase among hospitalized cases.
Perhaps due to a focus on hip fracture prevention, this study shows that while the incidence rate of hospitalized hip fractures has decreased, other fall-related hospitalized fractures have increased.
Potentially, this could be indicative of a healthier younger elderly, coupled with a frailer older elderly requiring more comprehensive healthcare also for less serious injuries. Further research is needed to confirm our results.
Previous studies have indicated increasing trends of hospitalized fall-related injuries amongst elderly. Whether this is true also in Sweden is unknown though it is important to study considering the potential societal impact. Data were obtained regarding hospitalized injuries with falls as external cause among those aged 65 years and above with information on injury type, gender and age, on a yearly basis, from 2001 to 2010. Age- and sex-specific incidence rates were calculated (per 100,000 population) for all fall-related injuries, and for each injury type and trend lines were drawn. Linear regression analyses and percentage change were calculated for the types of fall-related injuries. A decreasing incidence was observed in the younger age groups (65-79 years) with greater decreases amongst women (women: -14.6%, men 65-79 years: -10.5%). However, increasing rates were observed in the older age group (80 years and above), with greater increases amongst men (women: 4.3%, men: 11.4%). Superficial injuries showed greater increases than fractures amongst those aged 80 years and above. This study indicates that older elderly in Sweden are increasingly being hospitalized for less serious injuries. This changing injury panorama is important to include in the future planning of both health care and fall-related prevention.
Endotoxins are microbiological agents which ubiquitously exist in an indoor environment, and are believed to be causal agents for a number of diseases. This study investigated the indoor levels and determinants of endotoxins and their impact on asthma and allergy diseases among Swedish pre-school children. House dust samples from 390 homes of 198 case children with asthma and allergy and 202 healthy control children were collected in the Dampness Building and Health (DBH) study. House dust endotoxin levels in the child's bedroom and living rooms ranged from 479-188,000 EU/g dust and from 138-942,000 EU/g dust, respectively. Pet-keeping and agricultural activities were significantly associated with the higher endotoxin concentration levels in indoor dust. Endotoxins in theindoor environment did not associate to asthma and allergy diseases in the children. However, we found an association between endotoxins and the presence of disease symptoms in the sub-group of families without indoor pets.
This paper describes the background, aim and study design for the Swedish SELMA study that aimed to investigate the importance of early life exposure during pregnancy and infancy to environmental factors with a major focus on endocrine disrupting chemicals for multiple chronic diseases/disorders in offspring.
The cohort was established by recruiting women in the 10th week of pregnancy. Blood and urine from the pregnant women and the child and air and dust from home environment from pregnancy and infancy period have been collected. Questionnaires were used to collect information on life styles, socio-economic status, living conditions, diet and medical history.
Of the 8394 reported pregnant women, 6658 were invited to participate in the study. Among the invited women, 2582 (39%) agreed to participate. Of the 4076 (61%) non-participants, 2091 women were invited to a non-respondent questionnaire in order to examine possible selection bias. We found a self-selection bias in the established cohort when compared with the non-participant group, e.g. participating families did smoke less (14% vs. 19%), had more frequent asthma and allergy symptoms in the family (58% vs. 38%), as well as higher education among the mothers (51% vs. 36%) and more often lived in single-family houses (67% vs. 60%).
These findings indicate that the participating families do not fully represent the study population and thus, the exposure in this population. However, there is no obvious reason that this selection bias will have an impact on identification of environmental risk factors.
Previous trend studies have shown large increases in hip fracture incidence rates among the elderly. International research, however, suggests a levelling off, or decline, of hip fracture incidence rates, although for Sweden this remains to be studied.
Data were obtained regarding hip fractures among individuals 65 years and above from 1987 to 2009. Analysis was performed in three steps. First, age- and sex-specific trends in hip fracture rates per 100 000 and the mean age when sustaining a hip fracture were analysed. Secondly, the annual percentage change was used to compare time periods that helped to quantify changes in secular trends. Finally, linear and Poisson regression models were used to examine the trend data and observed rates.
The absolute number of hip fractures among the elderly in Sweden has largely remained constant between 1987 and 2009, while incidence rates have decreased for all age- and sex-specific groups, with the largest changes in the younger age groups and among women. The mean age of sustaining a hip fracture has increased for both men and women.
This study supports other international studies in showing a decrease in hip fracture incidence rates among the elderly, especially since the mid-1990s.