Geochemical correlates to type 1 diabetes incidence in southeast Sweden: an environmental impact?

The authors' aim was to explore whether geological factors contribute to geographical variation in the incidence of type 1 diabetes. All children diagnosed with type 1 diabetes in southeastern Sweden during 1977-2006 were defined geographically by their place of residence and were allocated x and y coordinates in the national grid. The population at risk, all children 0-16 years of age, was geocoded in a similar manner. Three of the analyzed minerals in moraine and one of the analyzed minerals in brook water plants were significantly associated with type 1 diabetes at the time of diagnosis. Additionally, the birthplace of the children who subsequently developed diabetes differed in relation to some of the minerals. In communities with high incidence and in communities with low incidence, children were diagnosed with type 1 diabetes in areas with the same high or low level of elements. The authors' findings in their pilot study indicate a possible geographical covariation of incidence and some geological factors.

Health effects and exposure to polychlorinated biphenyls (PCBs) and metals in a contaminated community.

Environmental measurements carried out by local authorities during the 1970s, 80s and 90s in an area contaminated by hundreds of years of industrial activities have revealed high levels of zinc (Zn), copper (Cu), lead (Pb) and cadmium (Cd) in soil, vegetables, root crops, berries and mushrooms. In 1972, a large quantity of oil contaminated with polychlorinated biphenyls (PCBs) was accidentally spilled into the river running through the village. To investigate the possible health effects of exposure from local sources, all cancer diagnoses, registered in 1960-2003 for individuals living in the study area, were collected from the regional cancer register of southeast Sweden. The total cancer incidence was non-significantly decreased both among males and females as compared to national rates (SIR=0.91) for each gender. Among males, increased risks, of border-line significance, were seen for testicular cancer and lymphomas as well as significantly decreased risks for cancer in the rectum, respiratory system and brain. Information on lifetime residence, occupation, smoking habits, diseases, childbirth and food consumption, was collected via questionnaires from cancer cases and randomly selected controls. In both genders combined, significant associations were found for total cancer and high consumption of local perch, and for lymphomas and high consumption of both perch and pikeperch. Female breast cancer was significantly associated with high consumption of local perch and pike as well as with work in metal production. Mothers residing in the parish before the age of five reported significantly more preterm child deliveries. In spite of study limitations, the results indicate that residing in a rural contaminated area may contribute to the development of certain cancers and reproductive effects. In females, high consumption of local fish was shown to be the strongest determinant for total cancer, while in males, the strongest determinant was residing in the study area the first five years of life. Further research including validation of exposure using biomarkers is required to verify the findings as well as future studies in other polluted areas in Sweden with larger population bases.

Randomised prostate cancer screening trial: 20 year follow-up.

OBJECTIVE: To assess whether screening for prostate cancer reduces prostate cancer specific mortality. DESIGN: Population based randomised controlled trial. SETTING: Department of Urology, Norrköping, and the South-East Region Prostate Cancer Register. PARTICIPANTS: All men aged 50-69 in the city of Norrköping, Sweden, identified in 1987 in the National Population Register (n = 9026). INTERVENTION: From the study population, 1494 men were randomly allocated to be screened by including every sixth man from a list of dates of birth. These men were invited to be screened every third year from 1987 to 1996. On the first two occasions screening was done by digital rectal examination only. From 1993, this was combined with prostate specific antigen testing, with 4 µg/L as cut off. On the fourth occasion (1996), only men aged 69 or under at the time of the investigation were invited. MAIN OUTCOME MEASURES: Data on tumour stage, grade, and treatment from the South East Region Prostate Cancer Register. Prostate cancer specific mortality up to 31 December 2008. RESULTS: In the four screenings from 1987 to 1996 attendance was 1161/1492 (78%), 957/1363 (70%), 895/1210 (74%), and 446/606 (74%), respectively. There were 85 cases (5.7%) of prostate cancer diagnosed in the screened group and 292 (3.9%) in the control group. The risk ratio for death from prostate cancer in the screening group was 1.16 (95% confidence interval 0.78 to 1.73). In a Cox proportional hazard analysis comparing prostate cancer specific survival in the control group with that in the screened group, the hazard ratio for death from prostate cancer was 1.23 (0.94 to 1.62; P = 0.13). After adjustment for age at start of the study, the hazard ratio was 1.58 (1.06 to 2.36; P = 0.024). CONCLUSIONS: After 20 years of follow-up the rate of death from prostate cancer did not differ significantly between men in the screening group and those in the control group. Trial registration Current Controlled Trials, ISRCTN06342431.

Risk of malignancies in relation to terrestrial gamma radiation in a Swedish population cohort.

Results of epidemiological studies on terrestrial gamma radiation (TGR) and related malignancies have not been consistent. This study is a thorough examination of this relationship. Records on all individuals living in two Swedish counties in 1973, along with their annual dwelling coordinates during the 28-year follow-up period, were retrieved from the National Archives and Statistics Sweden. We used Geographical Information System (GIS) to match the individuals' dwelling coordinates annually to the TGR given in 200×200 m grids produced by the Geological Survey of Sweden. Cases of malignancies and deaths were retrieved from the Swedish Cancer Register. During the follow-up period 61,503 incident cases were included in the analyses and in total 11 million person-years were recorded. Cox regression was used both in a linear continuous model and analyses of six exposure categories. Adjustments were made for sex, age, and population density. The hazard ratio (HR) per 100 nanoGray/hour (nGy/h) was significantly increased for total malignancies and for several sites; however, contrary to expectations, an obvious and anticipated linear exposure-response relationship could not be identified. With the lowest exposure category (0-60 nGy/h) as reference, a statistically significantly increased HR for total malignancies was seen in all exposure categories, except in the highest category 96-366 nGy/h. For breast cancer, thyroid cancer and leukaemia an obvious exposure-response could not be seen.

Schoolyard physical activity in 14-year-old adolescents assessed by mobile GPS and heart rate monitoring analysed by GIS.

BACKGROUND: Environmental settings seem to influence the activity patterns of children in neighbourhoods and schoolyards, the latter being an important arena to promote physical activity (PA) in school children. New technology has made it possible to describe free-living PA in interaction with the environment. AIMS OF STUDY: This study focused on how schoolyard environments influenced the activity patterns and intensity levels in 14-year-old children and whether PA levels in adolescents complied with official recommendations. Another objective was to introduce methodology of using a mobile global positioning system (GPS) device with synchronous heart rate (HR) recordings as a proxy for PA level and a geographical information system (GIS) for spatial analyses. METHODS: The sample constituted of 81 children (aged 14 years) from two schools. Movement patterns and activity levels were recorded during lunch break applying a GPS Garmin Forerunner 305 with combined HR monitoring and analysed in a GIS by an overlaid grid and kriging interpolation. RESULTS: Spatial data from GPS recordings showed particular movement patterns in the schoolyards. Low activity levels (mean HR < 120 bpm) dominated in both schools with no gender differences. Activities located to a handball goal area showed the highest monitored HR (>160 bpm) with higher intensity in girls than in boys. CONCLUSIONS: Movement patterns and PA generated in GIS for visualisation and analysis enabled direct and realistic description of utilising of schoolyard facilities and activity levels. Linking GPS data and PA levels to spatial structures made it possible to visualise the environmental interaction with PA and which environments promoted low or high PA.

Women with low-energy fracture should be investigated for osteoporosis.

INTRODUCTION: Treatment of osteoporosis is becoming more effective, but methods to identify patients who are most suitable for investigation and treatment are still being debated. Should any type of fracture have higher priority for investigation of osteoporosis than any other? Is the number of previous fractures useful information? MATERIAL AND METHODS: We investigated 303 consecutive women patients between 55 and 75 years of age who had a newly diagnosed low-energy fracture. They answered a questionnaire on previous fractures which also dealt with risk factors. Bone mineral density (BMD) was measured at the hip, lumbar spine, and forearm. RESULTS: The distribution of fracture location was: distal forearm 56%, proximal humerus 12%, vertebra 18%, and hip 13%, all with similar age. Half of the subjects had had at least one previous fracture before the index fracture, 19% had had two previous fractures, and 6% had had three or more previous fractures. Patients with vertebral or hip fracture had lower BMD and had had more previous fractures than patients with forearm or humerus fractures. There was an inverse correlation between number of fractures and BMD. Osteoporosis was present in one-third of patients with forearm fracture, in one-half of those with hip or humerus fracture, and in two-thirds of those with vertebral fracture. INTERPRETATION: Vertebral fractures were the strongest marker of low BMD and forearm fractures the weakest. The number of previous fractures is helpful information for finding the most osteoporotic patient in terms of severity. Investigation of osteoporosis therefore seems warranted in every woman between the ages of 55 and 75 with a recent low-energy fracture, with highest priority being given to those with vertebral, hip, or multiple fractures.

Evaluation of an osteoporosis and fall risk intervention program for community-dwelling elderly. A quasi-experimental study of behavioral modifications.

BACKGROUND AND AIMS: Osteoporosis and fall fractures are increasing problems amongst the elderly. The aim of this study was to explore whether combined population-based and individual interventions directed at risk factors for osteoporosis and falls result in behavioral changes in an elderly population. METHODS: A quasi-experimental design was used for the study. Persons aged >or=65 years were randomly selected in the intervention and control community. An intervention program was managed from the primary health care center and delivered to the community. Health education was designed to increase awareness of risk factors for the development of osteoporosis and falling. Questionnaires about lifestyle, health, previous fractures, safety behavior and physical activity level were distributed at baseline in 1989 and at the follow-ups in 1992 and 1994 in both communities. RESULTS: There was a difference of 17.7% between the dual intervention (receiving both population-based and individual interventions) and the control samples regarding the self-reported use of shoe/cane spikes, and a difference of 20.5% regarding the reported "moderate level" of physical activity in 1994. There was an increase in the number of participants in the dual intervention sample who, at baseline, had not reported equipping their homes with non-slip mats and removing loose rugs but who did report these changes in 1994. The increase in the reported use of shoe/cane spikes in the dual intervention sample was observed mainly for the period 1992-1994. CONCLUSIONS: A public health intervention model, including both population-based and individual interventions, can contribute to behavioral changes in the prevention of falls and changed physical activity patterns amongst elderly people.

Common biochemical markers of bone turnover predict future bone loss: a 5-year follow-up study.

BACKGROUND: Bone mineral density (BMD) is used to follow gain or loss of bone mass but cannot detect changes within a short period of time. Biochemical markers of bone turnover may be of value for prediction of individual bone loss. METHODS: We studied the relation between common inexpensive markers of bone turnover (serum alkaline phosphatase (ALP), osteocalcin (OC), urinary hydroxyproline (OHPr), and calcium (Ca)), BMD, age, and menopause in a combined cross-sectional and longitudinal design comprising 429 pre- and postmenopausal randomly selected women aged 21-79 years (mean 50 years). A follow-up was initiated after 5 years (including 192 of these women), which focused on changes in bone mass and the ability of these four common markers of bone turnover (sampled at baseline) to predict future bone loss. RESULTS: A marked increase was observed for all markers at the beginning of menopause. During the postmenopausal period ALP and Ca decreased to near premenopausal levels, while OC and OHPr remained high even 15 years after menopause. We also found inverse correlations at baseline between the bone markers and BMD, independent of the selected marker or skeletal site, r=-0.14 to -0.46, P<0.05. The correlations between ALP, OC, OHPr, and subsequent bone loss over 5 years, was significant for arm, r=-0.23 to -0.36, P<0.01. Baseline levels of all bone markers correlated significantly at group level with the 5-year follow-up of BMD for all sites. The ability of markers to predict individual bone loss was estimated by a multivariate regression model, which included baseline BMD, age, and body mass index as independent variables. ROC analysis showed a validity of approximately 76% for the forearm model, but was lower for the hip (55%) and lumbar spine (65%). CONCLUSIONS: These data show that the common inexpensive biochemical markers of bone turnover ALP, OC, OHPr, and Ca were related to the current bone mass and, moreover, provides information about future bone loss at the individual level. Future investigations should include an evaluation of the clinical relevance of markers of bone turnover in relation to fracture risk.

Impact of a community-based osteoporosis and fall prevention program on fracture incidence.

Associations between a 10-year community-based osteoporosis and fall prevention program and fracture incidence amongst middle-aged and elderly residents in an intervention community are studied, and comparisons are made with a control community. A health-education program was provided to all residents in the intervention community, which addressed dietary intake, physical activity, smoking habits and environmental risk factors for osteoporosis and falls. Both communities are small, semi-rural and situated in Ostergotland County in southern Sweden. The analysis is based on incidences of forearm fractures in the population 40 years of age or older, and hip fractures in the population 50 years of age or older. Data for three 5-year periods (pre-, early and late intervention) are accumulated and compared. In the intervention community, forearm fracture incidence decreased in women. There are also tendencies towards decreasing forearm fracture incidence in men, and towards decreasing trochanteric hip fracture incidences in women and in men in the late intervention period. No such changes in fracture incidences are found in the control community. Cervical hip fracture incidence did not change in the intervention and the control communities. Although the reported numbers of fractures are small (a total of 451 forearm and 357 hip fractures), the numbers are based on total community populations and thus represent a true difference. The decrease in forearm fracture incidence among women, and the tendency towards decreasing trochanteric hip fractures, in contrast to the absence of change in cervical hip fractures, might be mainly due to a more rapid effect of fall preventive measures than an increase in bone strength in the population. For the younger age groups an expected time lag between intervention and effect might invalidate the short follow-up period for outcome measurements. Thus, the effect of the 10-year intervention program on fracture incidence should be followed during an extended post-intervention period.

Clinical consequences of screening for prostate cancer: 15 years follow-up of a randomised controlled trial in Sweden.

OBJECTIVE: To test the feasibility of a population-based prostate cancer screening programme in general practice and explore the outcome after a 15-year follow-up period. METHODS: From the total population of men aged 50-69 years in Norrköping (n = 9026) every sixth man (n = 1494) was randomly selected to be screened for prostate cancer every third year over a 12-year period. The remaining 7532 men were treated as controls. In 1987 and 1990 only digital rectal examination (DRE) was performed, in 1993 and 1996 DRE was combined with a test for Prostate-Specific Antigen (PSA). TNM categories, grade of malignancy, management and cause of death were recorded in the South-East Region Prostate Cancer Register. RESULTS: There were 85 (5.7%) cancers detected in the screened group (SG), 42 of these in the interval between screenings, and 292 (3.8%) in the unscreened group (UG). In the SG 48 (56.5%) of the tumours and in the UG 78 (26.7%) were localised at diagnosis (p < 0.001). In the SG 21 (25%) and in the UG 41 (14%) received curative treatment. There was no significant difference in total or prostate cancer-specific survival between the groups. CONCLUSIONS: Although PSA had not been introduced in the clinical practice at the start of the study, we were still able to show that it is possible to perform a long-term population-based randomised controlled study with standardised management and that screening in general practice is an efficient way of detecting prostate cancer whilst it is localised. Complete data on stage, treatment and mortality for both groups was obtained from a validated cancer register, which is a fundamental prerequisite when assessing screening programmes.

Is calcaneal stiffness more sensitive to physical activity than forearm bone mineral density? A population-based study of persons aged 20-79 years.

AIMS: The aim of this study was to investigate the associations between forearm bone mineral density (BMD), calcaneal stiffness, and physical activity levels in a normal population using different non-invasive methods. METHODS: The participants were invited to undergo bone measurements using single photon absorptiometry of the forearm and quantitative ultrasound (QUS) of the calcaneal bone, and also to complete a questionnaire. Physical activity levels were designated low, moderate, and high in the question on leisure-time activity. RESULTS: There were 956 participants included in the present study. Forearm BMD in the eighth age decade was 0.40 g/cm2 (95% CI 0.33-0.46 g/cm2) lower than in the third decade among women and 0.28 g/cm2 (95% CI 0.18-0.37 g/cm2) lower among men. The differences in calcaneal stiffness between the same age decades were 22.4 (95% CI 17.5-27.4) among women and 15.8 (95% CI 8.0-23.5) among men. The correlation between forearm BMD and calcaneal stiffness was 0.58 (95% CI 0.52-0.64) in women and 0.34 (95% CI 0.25-0.42) in men. Reported moderate and high leisure-time activity levels in both genders were associated with higher calcaneal stiffness but not with forearm BMD. CONCLUSIONS: The QUS may be used to measure the effect of present physical activity levels on calcaneal bone at the population level. Further longitudinal studies are warranted in order to determine the most appropriate non-invasive method in population-based studies.

Chlorination byproducts and nitrate in drinking water and risk for congenital cardiac defects.

Drinking water disinfection byproducts have been associated with an increased risk for congenital defects including cardiac defects. Using Swedish health registers linked to information on municipal drinking water composition, individual data on drinking water characteristics were obtained for 58,669 women. Among the infants born, 753 had a cardiac defect. The risk for a cardiac defect was determined for ground water versus surface water, for different chlorination procedures, and for trihalomethane and nitrate concentrations. Ground water was associated with an increased risk for cardiac defect when crude rates were analyzed but after suitable adjustments this excess rate was found to be determined by chlorination procedures including chlorine dioxide. Chlorine dioxide appears itself as an independent risk factor for cardiac defects (adjusted odds ratio 1.61 (95%CI 1.00-2.59)). The risk for cardiac defects increased with increasing trihalomethane concentrations (P=0.0005). There was an indicated but statistically nonsignificant excess risk associated with nitrate concentration. The individual risk for congenital cardiac defect caused by chlorine dioxide and trihalomethanes is small but as a large population is exposed to public drinking water, the attributable risk for cardiac defects may not be negligible.

Knowledge of osteoporosis in a Swedish municipality--a prospective study.

BACKGROUND: As a part of the Vadstena Osteoporosis Prevention Project, the knowledge of osteoporosis was examined before the intervention program started, after 5 and 10 years. METHODS: At baseline (in 1989) 15% of the population in two Swedish municipalities was randomly invited to the study. The participants in the study group were invited for examination by forearm bone densitometry and a questionnaire concerning lifestyle and risk factors for osteoporosis and also knowledge of osteoporosis, while the subjects in the control group were examined only by questionnaire. Follow-ups were made in 1994 and in 1999. Meanwhile education about osteoporosis was given to the study group, to the public, and to various professionals in the study community. RESULTS: There was a difference in the level of knowledge between the groups prior to the intervention. The rate of increment did not differ significantly between the groups for the study period. Previous participants had 0.58 higher score than new participants in the study group in 1994 (P = 0.031) and 0.76 higher score in 1999 (P < 0.001) regarding the total number of correct answers. The women in the study group had 0.63 higher score than the men in 1994 (P = 0.016) and 1.03 higher score in 1999 (P < 0.001) regarding the total number of correct answers. CONCLUSION: There was no significant effect of a general intervention program concerning the knowledge of osteoporosis in participants in the intervention area compared to the control area.