Geographic variations in hip fracture incidence in a high-risk country stretching into the Arctic: a NOREPOS study.

There are geographic variations in hip fracture incidence rates across Norway, with a lower incidence in the coastal areas of the southwest and in the Arctic north, contrary to what may be expected with regard to vitamin D exposure from sunlight. The regional differences have become smaller in recent years. INTRODUCTION: To investigate geographic variation in hip fracture incidence within Norway and regional differences in time trends. METHODS: All hip fractures treated in Norwegian hospitals 2002-2013 were included, and demographic information was obtained from Statistics Norway. Age-standardized incidence rates were calculated separately for 19 counties. Incidence rate ratios with 95% confidence intervals for county differences and time trends were estimated using Poisson regression. RESULTS: Age-standardized number of hip fractures per 10,000 person-years varied between counties from 69 to 84 in women and from 34 to 41 in men. The highest rates were observed in the southeastern capital city of Oslo, while rates were low in the four northernmost counties. There was an east-west gradient, with lower incidence in the coastal southwest compared with the southeast. Women showed a statistically significant decline during 2002-2013 in almost all counties (up to 31%). In men, only a few counties showed a decline. In both genders, hip fracture rates at age 80 in the combined five counties with the highest rates were significantly higher than in the combined five counties with the lowest rates across the period, although the trends converged over time. CONCLUSIONS: In Norway, the hip fracture incidence was lower in the north compared with the south. In addition, we observed an east-west gradient with the highest incidence in the southeast and lower incidence in the coastal southwest. While there has been an overall declining trend in hip fracture incidence over time, regional differences are still apparent.

Excess mortality following hip fracture: impact of self-perceived health, smoking, and body mass index. A NOREPOS study.

Self-perceived health, smoking, and body mass index measured years before the hip fracture predicted excess post-hip fracture mortality, and even hip fracture patients with the most favorable levels of these risk factors had higher mortality than subjects who did not fracture. INTRODUCTION: This study aimed to investigate the impact of pre-fracture self-perceived health, smoking, and body mass index (BMI) on excess post-hip fracture mortality using matched peers without hip fracture as reference. METHODS: The study was based on the Cohort of Norway (CONOR) consisting of 10 regional health studies (1994-2003) and the NOREPOS hip fracture database (1994-2008). A matched cohort design was used to compare survival between hip fracture patients and subjects without fracture (matched on gender, age at participation in CONOR, and study site). Subjects aged ≥60 years were included. Hazard ratios were estimated using stratified Cox regression. Age-standardized mortality was also calculated. RESULTS: Overall, hip fracture patients (N = 3177) had a 2.26-fold (95 % CI 2.13, 2.40) increased mortality compared to matched subjects (N = 20,282). The highest excess mortality was found in hip fracture patients reporting poor health (HR 4.08, 95 % CI 3.17, 5.26) and daily smoking (HR 3.25, 95 % CI 2.89, 3.66) and in patients with BMI <18.5 (HR 3.07, 95 % CI 2.11, 4.47) prior to the fracture. However, excess mortality was also observed in hip fracture patients in all other categories of BMI, self-perceived health, and smoking. CONCLUSIONS: Information on self-perceived health, smoking, and BMI collected years before hip fracture predicted excess post-hip fracture mortality, and even hip fracture patients with the most favorable levels of these risk factors had higher mortality than the matched subjects who did not fracture. This suggests that both pre-fracture health status and factors related to the hip fracture itself might affect post-hip fracture mortality.

Perfluoroalkyl substances measured in breast milk and child neuropsychological development in a Norwegian birth cohort study.

Perfluoroalkyl substances (PFASs) are chemicals with potential neurotoxic effects although the current evidence is still limited. This study investigated the association between perinatal exposure to perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) and neuropsychological development assessed at 6, 12 and 24 months. We measured PFOS and PFOA in breast milk samples collected one month after delivery by mothers of children participating in the HUMIS study (Norway). Cognitive and psychomotor development was measured at 6 and at 24 months using the Ages and Stages Questionnaire (ASQ-II). Behavioral development was assessed using the infant-toddler symptom checklist (ITSC) at 12 and at 24 months. Weighted logistic regression and weighted negative binomial regression models were applied to analyze the associations between PFASs and ASQ-II and ITSC, respectively. The median concentration of PFOS was 110 ng/L, while the median for PFOA was 40 ng/L. We did not detect an increased risk of having an abnormal score in ASQ-II at 6 months or 24 months. Moreover, no consistent increase in behavioral problems assessed at 12 and 24 months by ITSC questionnaire was detected. We observed no association between perinatal PFOS and PFOA exposure and early neuropsychological development. Further longitudinal studies are needed to confirm the effects of these compounds on neuropsychological development in older children.

Increased risk of atrial fibrillation among elderly Norwegian men with a history of long-term endurance sport practice.

Atrial fibrillation (AF) is the most common cardiac arrhythmia. The prevalence increases with increasing age. In middle-aged men, endurance sport practice is associated with increased risk of AF but there are few studies among elderly people. The aim of this study was to investigate the role of long-term endurance sport practice as a risk factor for AF in elderly men. A cross-sectional study compared 509 men aged 65-90 years who participated in a long-distance cross-country ski race with 1768 men aged 65-87 years from the general population. Long-term endurance sport practice was the main exposure. Self-reported AF and covariates were assessed by questionnaires. Risk differences (RDs) for AF were estimated by using a linear regression model. After multivariable adjustment, a history of endurance sport practice gave an added risk for AF of 6.0 percent points (pp) (95% confidence interval 0.8-11.1). Light and moderate leisure-time physical activity during the last 12 months reduced the risk with 3.7 and 4.3 pp, respectively, but the RDs were not statistically significant. This study suggests that elderly men with a history of long-term endurance sport practice have an increased risk of AF compared with elderly men in the general population.

The associations between maternal pre-pregnancy body mass index or gestational weight change during pregnancy and body mass index of the child at 3 years of age.

OBJECTIVE: To estimate the associations between maternal pre-pregnancy body mass index (BMI) or gestational weight change (GWC) during pregnancy and offspring BMI at 3 years of age, while taking several pre-and postnatal factors into account. DESIGN: The Norwegian Mother and Child Cohort Study is a population-based pregnancy cohort study of women recruited from all geographical areas of Norway. SUBJECTS: The study includes 31 169 women enrolled between 2000 and 2009 through a postal invitation sent to women at 17-18 weeks of gestation. Data collected from 5898 of the fathers were included. MAIN OUTCOME MESURES: Offspring BMI at 3 years was the main outcome measured in this study. RESULTS: Mean maternal pre-pregnancy BMI was 24.0 kg m(-2) (s.d. 4.1), mean GWC in the first 30 weeks of gestation was 9.0 kg (s.d. 4.1) and mean offspring BMI at 3 years of age was 16.1 kg m(-2) (s.d. 1.5). Both maternal pre-pregnancy BMI and GWC were positively associated with mean offspring BMI at 3 years of age. Pre-pregnancy BMI and GWC also interacted, and the strength of the interaction between these two factors was strongly associated with the increase in offspring BMI among mothers who gained the most weight during pregnancy and had the highest pre-pregnancy BMI. Our findings show that results could be biased by not including pre-pregnant paternal BMI. CONCLUSION(S): This large population-based study showed that both maternal pre-pregnancy BMI and GWC were positively associated with mean offspring BMI at 3 years of age.

Anaemia prevalence and associated sociodemographic and dietary factors among Palestinian adolescents in the West Bank.

Anaemia still persists among children and women of childbearing age in Palestine. We investigated the prevalence of anaemia and associated factors among Palestinian school adolescents (aged 13-15 years) in Ramallah and Hebron governorates. Haemoglobin levels were measured to assess the prevalence of anaemia. The prevalence of anaemia was significantly higher in Hebron than in Ramallah among boys (22.5% versus 6.0% respectively), while among girls the figures were similar (9.2% and 9.3% respectively). Linear binomial regression analysis showed that among boys, anaemia was independently associated with residence in Hebron and higher standard of living, while among girls, anaemia was associated with higher father's education. Consumption of iron-rich foods, as recorded in food frequency questionnaires, had no significant effects on anaemia prevalence in both boys and girls.

Anaemia prevalence and associated sociodemographic and dietary factors among Palestinian adolescents in the West Bank

Anaemia still persists among children and women of childbearing age in Palestine. We investigated the prevalence of anaemia and associated factors among Palestinian school adolescents [aged 13-15 years] in Ramallah and Hebron governorates. Haemoglobin levels were measured to assess the prevalence of anaemia. The prevalence of anaemia was significantly higher in Hebron than in Ramallah among boys [22.5% versus 6.0% respectively], while among girls the figures were similar [9.2% and 9.3% respectively]. Linear binomial regression analysis showed that among boys, anaemia was independently associated with residence in Hebron and higher standard of living, while among girls, anaemia was associated with higher father's education. Consumption of iron-rich foods, as recorded in food frequency questionnaires, had no significant effects on anaemia prevalence in both boys and girls

Estimation of peak oxygen uptake from maximal power output among 9-10 year-old children in Lhasa, Tibet.

AIM: The aims of the present study of Tibetan and Han Chinese children were to establish prediction equations for peak oxygen uptake (VO2peak) using conventional power output measures, and to compare with prediction models based on data from sea level. METHODS: In 25 Tibetan children and 15 Han Chinese children aged 9-10 years, living in Lhasa at 3700 meters above sea level, VO2peak was measured directly using a portable oxygen analyzer, and predicted from maximal power output (Wmax) using a maximal cycle ergometer test. RESULTS: In multiple regression analyses with VO2peak as dependent variable and Wmax and sex as covariates, a total adjusted R2 of 0.76 and 0.82 were found in Tibetan and Han Chinese children, separately. Sex made a unique, and statistically significant, contribution to the prediction of VO2peak. Three equations derived from sea level data were compared with the equations from the present study. None of the three could accurately predict the direct measured V.O2peak, and predictions differed in an unsystematic manner, including over- or underestimation and no differentiation between genders. CONCLUSION: Peak oxygen uptake could be estimated from Wmax and sex in a progressive cycle ergometer test among children living at 3700 meters in Tibet. The estimate of VO2peak is probably more valid using the present equations than prediction models based on data from sea level. The equations used for the prediction are: Bianba(eqT): (l·min(-1)) = 0.5419 + (0.0096· Wmax) - (0.0562· sex); boys=0; girls=1 Bianba(eqH): (l·min(-1)) = 0.4060 + (0.0124· Wmax) - (0.1775· sex); boys=0; girls=1.

Folic acid supplements in pregnancy and early childhood respiratory health.

BACKGROUND: Folate supplementation is recommended for pregnant women to reduce the risk of congenital malformations. Maternal intake of folate supplements during pregnancy might also influence childhood immune phenotypes via epigenetic mechanisms. OBJECTIVE: To investigate the relationship between folate supplements in pregnancy and risk of lower respiratory tract infections and wheeze in children up to 18 months of age. METHODS: In the Norwegian Mother and Child Cohort Study, questionnaire data collected at several time points during pregnancy and after birth on 32,077 children born between 2000 and 2005 were used to assess the effects of folate supplements during pregnancy on respiratory outcomes up to 18 months of age, while accounting for other supplements in pregnancy and supplementation in infancy. RESULTS: Folate supplements in the first trimester were associated with increased risk of wheeze and respiratory tract infections up to 18 months of age. Adjusting for exposure later in pregnancy and in infancy, the relative risk for wheeze for children exposed to folic acid supplements in the first trimester was 1.06 (95% CI 1.03 to 1.10), the relative risk for lower respiratory tract infections was 1.09 (95% CI 1.02 to 1.15) and the relative risk for hospitalisations for lower respiratory tract infections was 1.24 (95% CI 1.09 to 1.41). CONCLUSIONS: Folic acid supplements in pregnancy were associated with a slightly increased risk of wheeze and lower respiratory tract infections up to 18 months of age. The results suggest that methyl donors in the maternal diet during pregnancy may influence respiratory health in children consistent with epigenetic mechanisms.

Cardiorespiratory fitness in relation to self-reported physical function in cancer patients after chemotherapy.

AIM: The aim of this study was to estimate the association between objective cardiorespiratory fitness (CRF) and subjective self-reported physical function, taking into account the influence of mental distress. We hypothesized an association between these parameters, since they might be thought to measure parts of the same phenomenon. METHODS: Approximately 1 month after discontinuation of all primary treatment, 90 cancer patients aged 18-50 years treated with chemotherapy were surveyed. CRF was determined by the Astrand-Ryhming indirect cycle ergometer test, which indicate peak VO2 in mL x kg(-1) x min(-1) (predicted VO2max). Self-reported physical function was assessed by The European Organisation for Research and Treatment of Cancer Core Quality of Life Questionnaire (EORTC QLQ-C30). The relation between VO2max and self-reported physical function was estimated by multiple linear regression. Mental distress (assessed by The Hospital Anxiety and Depression scale), age, gender, body mass index (BMI), time from treatment to physical test and diagnoses were included as potential confounders. RESULTS: There was no association between predicted VO2max and self-reported physical function. Mental distress was negatively associated with self-reported physical function (P<0.001), but is not associated with predicted VO2max. CONCLUSIONS: The results suggest that predicted VO2max does not reflect self-reported physical function and vice versa in cancer patients after chemotherapy. If information about cardiac and/or pulmonary status is required, direct or indirect measures of VO2max should be used.

Parental reported bullying among Nordic children: a population-based study.

BACKGROUND: Bullying has been shown to be a serious problem amongst school children, but few studies have been population-based and included pre-school children. METHODS: The study is part of a cross-sectional comparative study in 1984 and 1996, focusing on children's and their families' health and welfare in the Nordic countries. At each point of time parents of 3000 randomly selected children aged 2-17 years in each of five Nordic countries received a postal questionnaire. Altogether approximately 20,000 questionnaires were completed. The prevalence of bullying, risk factors for bullying and possible effect factors were analysed. RESULTS: Parents reported bullying of their child in 15.1% of the cases. Bullying varied from 7.2% in Sweden to about 20% in Denmark and Finland. There was a small increase in bullying from 13.7% in 1984 to 16.4% in 1996. Bullying was most frequent in boys (OR: 1.4) and in children 2-6 and 7-12 years old (OR: 2.0 and 2.2 compared with older children). Children of single parents and of parents with low education had increased risks (OR: 1.4 and 1.4). Children with chronic conditions had higher risks for being bullied (OR: 2.3). In 1996 children with psychiatric/nervous problems and hyperactivity had high risks for being bullied (OR: 8.8 and 10.5) and for bullying others (3.9 and 3.5). Being bullied was associated with poor thriving and psychosomatic and psychological problems. No countries had national interventions before 1984, but Sweden had early focused on the problem and implemented a strong national policy before 1996. After 1996 national anti-bullying policies were strengthened in the Nordic countries, most in Sweden and Norway. CONCLUSION: Bullying is common among Nordic children, including pre-school children. Bullying is a threat to children's health, and augments problems in children with chronic conditions. The low prevalence of bullying in Sweden may be a result from sustained, strong anti-bullying policies. There is still a need for continuing interventions.

Cesarean delivery and cow milk allergy/intolerance.

The present study provides support for a positive association between cesarean delivery and persistent cow milk allergy/cow's milk intolerance. Correspondingly, a negative association was seen between cesarean delivery and early outgrown cow milk allergy/intolerance. A possible explanation is that cesarean delivery, rather than increasing the overall risk of food allergy, increases the risk of persistency of disease among food allergic children.

Definition and estimation of an actual reproduction number describing past infectious disease transmission: application to HIV epidemics among homosexual men in Denmark, Norway and Sweden.

Prevalence and incidence measures are the common way to describe epidemics. The reproduction number supplies information on the potential for growth or decline of an epidemic. We define an actual reproduction number for infectious disease transmission that has taken place. An estimator is suggested, based on the number of new infections observed in a given time-interval, the number of those infected at the start of the interval, and the length of the infectious period. That estimator is applied to HIV among men having sex with other men over the period, 1977-1995, in Scandinavia. The actual reproduction number was estimated with acceptable certainty from the period, 1981-1982, yielding a value of 15 secondary cases. A value of less than one secondary case was assessed for the period, 1988-1995, in Denmark and Sweden. The actual reproduction number gives us some additional understanding of the dynamics of epidemics, compared with prevalence and incidence curves.

Increased level of bronchial responsiveness in inactive children with asthma.

We estimated the association between bronchial responsiveness and hours of exercise per week in children with and without asthma. A random sample of school children (n = 2188), 6-16 years old, was enrolled in a cross-sectional study of asthma in Oslo using the ISAAC questionnaire. Lung function and bronchial responsiveness (BR) using methacholine was measured in a random sample of 80 children with asthma, wheeze and no asthma/no wheeze. The relation between hours of exercise per week and BR [log (DRS)] was estimated by linear regression. Sex and age were included as covariates. Hours of exercise were categorized in: none, 30 min, 1 h, 2-3 h, 4-6 h and 7 h or more. The mean values of log (DRS) were different in the low and high exercise groups for children with asthma (P = 0.02), whereas there was no effect of exercise on BR for children without asthma. BR increased with decreasing hours of exercise per week in children with asthma. The bronchial responsiveness decreased with 0.11 (95% CI -0.20, -0.01) pr unit in scale. This pattern was not present in children without asthma. The results suggest that there is a relation between hours of exercise per week and bronchial responsiveness in children with asthma.

Restricted diets in children with reactions to milk and egg perceived by their parents.

The aim of this study was to investigate the degree to which parents alter the diets of their children on the basis of perceived reactions. From a population-based sample of 2979 2-year old children with reactions to egg or milk perceived by their parents, one third had strict limitations on the intakes of these foods, representing 2.5% of the children in the cohort. In approximately 1 of 6 families the strict diets were initiated without consulting a doctor, and in a substantial proportion the restrictions were unwarranted. High maternal education level and irritability attributed to food were among the risk factors for unwarranted diets. On the other hand, many children, in whom an adverse reaction was verified, lacked appropriate diet restrictions. We conclude that the handling of adverse reactions to food frequently occurs outside the medical care system at the cost of correct diagnosis and appropriate diets.

Risk behaviour among blood donors who give blood in order to be tested for the human immunodeficiency virus.

BACKGROUND AND OBJECTIVES: There has been concern that some individuals may donate blood primarily motivated by the easy access to human immunodeficiency virus (HIV) testing, and that such donors may represent a risk to the transfusion service. In this article we focus on the risk behaviour of donors who reported that they gave blood in order to be HIV tested. MATERIALS AND METHODS: Anonymous questionnaires were given to 5859 blood donors. The response rate was 70%. RESULTS: Of the responders, 2.8% reported to have donated blood in order to be HIV tested. However, 87% of the donation-for-test group did not have any identified risk behaviour. CONCLUSIONS: The proportion who donated blood in order to be HIV tested was higher than expected, but the majority of the group did not have any identifiable HIV risk.

Risk behavior in Norwegian blood donors.

BACKGROUND: Blood banks ensure the safety of blood components by testing them for a set of known infectious agents and by careful selection of donors based on a self-administered questionnaire and an interview. The purpose of this study is to describe the risk behavior for sexually transmitted diseases in Norwegian blood donors. STUDY DESIGN AND METHODS: A survey of the sexual habits of 5,859 blood donors in the capital of Norway was performed by using anonymous questionnaires. The results were compared with a previous survey of 10,000 randomly selected Norwegian subjects aged 18 to 60 years. The response rates were 70.3 percent and 48.4 percent, respectively. RESULTS: Blood donors had considerably more education than the general population. Their general sexual behavior was similar to that of the rest of the population, although the blood donors had later sexual debut, fewer new partners per year, and a lower frequency of intercourse. In addition, homosexual experience among males was much lower in the donor group. Blood donors were less likely to engage in risk behavior for sexually transmitted diseases than were the general population. Nevertheless, 1.5 percent of the donors reported behavior that would have led to deferral had the behavior been disclosed at the predonation interview. Deferrable donors were more likely to be male and young and to have had many partners. CONCLUSION: Anonymous questionnaires reveal information that is not given at the time of blood donation.

Human T-cell lymphotropic virus testing of blood donors in Norway: a cost-effect model.

BACKGROUND: Human T-cell lymphotropic virus type I and II (HTLV-I and II) are human retroviruses that can be transmitted by transfusion of whole blood. An HTLV-I infection is associated with adult T-cell leukaemia (ATL) and with tropical spastic paraparesis (TSP). Antibody tests from 5.5 million European blood donors have shown that the HTLV prevalence is low, ranging from 0 to 0.02%. This paper examines costs and effects associated with the intervention of testing all new blood donors for HTLV. METHODS: A mathematical model was used to calculate the number of cases prevented by the intervention. For a given prevalence of HTLV in the blood donor population, the model calculates the number of recipients infected by transfusion, and the number of partners and offspring that will in turn be infected. The model then calculates the number of subjects with disease due to HTLV-I infection and the number of deaths from disease. From these numbers the measures of cost and effect are calculated. RESULTS: Testing all new blood donors for HTLV is calculated to cost US$ 9.2 million per life saved, or US$ 420,000 per quality adjusted life year gained by the intervention, when the HTLV prevalence among donors is 1 per 100,000. When the prevalence among donors is 10 per 100,000 the intervention will cost US$ 0.9 million per life saved, or US$ 41,000 per quality adjusted life year gained. The same analysis shows that testing blood donors for human immunodeficiency virus (HIV) saves money when the HIV prevalence among donors is above 0.7 per 100,000. CONCLUSION: For Norway, studies suggest a willingness to pay to save a statistical life of approximately US$ 1.2 million. The costs fall under this value when the number of infected persons is > or = 8 per 100,000 donors. The results are uncertain because of the uncertainty in HTLV infection and disease parameters.

Back-calculation based on HIV and AIDS registers in Denmark, Norway and Sweden 1977-95 among homosexual men: estimation of absolute rates, incidence rates and prevalence of HIV.

BACKGROUND: The Scandinavian countries, Denmark, Norway and Sweden, have established both HIV and AIDS registers to monitor the HIV epidemic. Information in such registers can be used to estimate the number of new HIV infections over time, incidence rates and prevalence. Information from the HIV registers made it possible to study what kind of effects such information had in the estimation process, compared with using information about new AIDS cases only. METHODS: A Markov model back-calculation approach was used. One model incorporated data on cases of both HIV and AIDS. Another model incorporated data on cases of AIDS only. Death or emigration prior to the onset of AIDS and effects of treatment were included in both models. RESULTS: Estimates of absolute rates of HIV for men who have sex with men (MSM) showed a distinct development in each country. Significant differences in incidence rates and prevalence of HIV among MSM were found between Scandinavian countries when information on diagnosed HIV was incorporated. Precision was improved when using both HIV and AIDS diagnosed cases compared with using AIDS cases only. The epidemic in Denmark was more extensive than in the two other countries for the whole study period. DISCUSSION: The results were fairly robust against reasonable variation in the model parameters. The more extensive epidemic in Denmark may have been caused by the homosexual culture denying that HIV was a disease more relevant to them than to others, until the HIV test was publicly available in 1985.

Work related risk factors for musculoskeletal complaints in the spinning industry in Lithuania.

OBJECTIVES: To describe the prevalence of self reported musculoskeletal complaints in the back, arms or neck, and legs among workers in the spinning industry, and to investigate the relations between these complaints and work related variables. METHODS: An interview based questionnaire survey was carried out in two spinning industry factories in Lithuania. RESULTS: The study group consisted of all workers in production (n = 363). Symptoms of the legs were the musculoskeletal symptom reported most often (61%). Many subjects had arms or neck (55%) or back problems (28%). 20% had experienced pain from all three sites. Almost 25% had had musculoskeletal pain every day and 16% had experienced constant pain during previous year. Packers had the highest risk of arms or neck problems whereas spinners had the highest risk of back or leg problems. Working in a strained posture (bending, work with arms raised up above shoulder level, and repetitive movements of the fingers) was associated with all three complaints. Only arms or neck complaints were associated with age. CONCLUSIONS: Musculoskeletal disorders are a common problem among workers producing gobelin or synthetic thread in Lithuania and working in a strained posture is a risk factor for developing musculoskeletal disorders in three body sites: legs, arms or neck, and back. To better understand the different aspects of physical load as risk factors, a more detailed study of the frequency of postural changes as well as an observation of individually adopted postures would be necessary. This applies to intervention studies in factories of the spinning industry to prevent complaints of the legs and shoulders.