Educational inequalities and self-reported health among men and women aged 18-49 years in Yangon Region, Myanmar: analysis of a population-based, cross-sectional study.

OBJECTIVES: To estimate the prevalence of good self-reported health (SRH) in subpopulations based on the social determinants of health and to investigate the association between education (measured in years of schooling) and good SRH among men and women aged 18-49 years in Yangon Region, Myanmar. DESIGN: Analysis of data from a population-based, cross-sectional study conducted in Yangon, Myanmar, from October to November 2016. A multistage sampling procedure was employed, and structured face-to-face interviews were conducted with standardised questions adapted from the Myanmar Demographic and Health Survey. Prevalence ratios (PRs) with 95% CIs were estimated using Poisson regression analyses by sex. SETTING: Urban and rural areas of Yangon Region, Myanmar. PARTICIPANTS: The sample included 2,506 participants (91.8% response rate) aged 18-49 years and excluded nuns, monks, soldiers, institutionalised people and individuals deemed too ill physically and/or mentally to participate. RESULTS: The prevalence of good SRH was 61.2% (95% CI 59.3 to 63.1), with higher rates among men (72.0%, 95% CI 69.3 to 74.5), younger individuals (69.2%, 95% CI 66.2 to 72.1), urban residents (63.6%, 95% CI 60.8 to 66.3), extended family dwellers (66.6%, 95% CI 63.7 to 69.4) and those with a higher level of education (66.0%, 95% CI 61.3 to 70.5). After adjusting for confounders (age and area of residence), the association between years of schooling and SRH (PR) was 1.01 (95% CI 1.01 to 1.02, p=0.002) in men and 1.01 (95% CI 0.99 to 1.02, p=0.415) in women. CONCLUSIONS: Good SRH was more prevalent among men than among women. Additionally, a 1-year increase in education was associated with a 1% increase in the prevalence of good SRH among men, whereas the association was not statistically significant among women. In order to enhance the educational benefits of health in Myanmar, we recommend a higher focus on the length of education and addressing gender inequalities in wage return from education.

A controlled weight loss intervention study among women of Somali background in Norway.

Background: Women of Somali background in Norway have a high prevalence of overweight and obesity, compared with women in the general Norwegian population. For lifestyle interventions to be applicable for immigrants to Norway, it is important to culturally tailor interventions in collaboration with relevant communities. The primary outcome was a difference in weight change between the intervention and control groups. Methods: In this interventional study, Somali women living in one borough of Oslo Municipality in Norway with body mass index (BMI) ≥27.0 kg.m-2 received a co-created, culturally tailored 12-month weight loss intervention consisting of 24 interactive sessions during the first three months, and monthly sessions for the next nine months, compared to a control group. Both groups were measured at baseline and 12 months. Results: A total of 169 participants were recruited, and 101 participants completed the follow-up. After multiple imputation, the mean difference in weight change adjusted for baseline weight, age, education, employment, marital status, number of children in the household and length of Norwegian residency was -1.6 kg (95 % CI -3.57, 0.43, p = 0.12) in the intervention compared to the control group. Conclusion: This culturally tailored intervention study demonstrated a modest non-significant effect on weight change after 12 months, possibly due to the short intervention duration and COVID-19. Further studies of a longer duration and considering the provision of childcare are needed to understand whether this approach can be transferred to other immigrant groups and genders.Trial registration: The study was registered at clinicaltrials.gov NCT04578067, 2020-09-29.

Does pain tolerance mediate the effect of physical activity on chronic pain in the general population? The Tromsø Study.

ABSTRACT: Knowledge is needed regarding mechanisms acting between physical activity (PA) and chronic pain. We investigated whether cold pain tolerance mediates an effect of leisure-time physical activity on the risk of chronic pain 7 to 8 years later using consecutive surveys of the population-based Tromsø Study. We included participants with information on baseline leisure-time PA (LTPA) and the level of cold pressor-assessed cold pain tolerance, who reported chronic pain status at follow-up as any of the following: chronic pain for ≥3 months, widespread chronic pain, moderate-to-severe chronic pain, or widespread moderate-to-severe chronic pain. We included 6834 participants (52% women; mean age, 55 years) in counterfactual mediation analyses. Prevalence decreased with severity, for example, 60% for chronic pain vs 5% for widespread moderate-to-severe chronic pain. People with one level higher LTPA rating (light to moderate or moderate to vigorous) at baseline had lower relative risk (RR) of 4 chronic pain states 7 to 8 years later. Total RR effect of a 1-level LTPA increase was 0.95 (0.91-1.00), that is, -5% decreased risk. Total effect RR for widespread chronic pain was 0.84 (0.73-0.97). Indirect effect for moderate-to-severe chronic pain was statistically significant at RR 0.993 (0.988-0.999); total effect RR was 0.91 (0.83-0.98). Statistically significantly mediated RR for widespread moderate-to-severe chronic pain was 0.988 (0.977-0.999); total effect RR was 0.77 (0.64-0.94). This shows small mediation of the effect of LTPA through pain tolerance on 2 moderate-to-severe chronic pain types. This suggests pain tolerance to be one possible mechanism through which PA modifies the risk of moderate-to-severe chronic pain types with and without widespread pain.

The medication-based Rx-Risk Comorbidity Index and risk of hip fracture - a nationwide NOREPOS cohort study.

BACKGROUND: Few previous studies have assessed overall morbidity at the individual level with respect to future risk of hip fracture. The aim of this register-based cohort study was to examine the association between morbidity measured by the medication-based Rx-Risk Comorbidity Index (Rx-Risk) and the risk of first hip fracture. METHODS: Individual-level data on medications dispensed from pharmacies (2005-2016) was retrieved from the Norwegian Prescription Database and used to calculate Rx-Risk for each calendar year. Information on first hip fractures (2006-2017) was obtained from a nationwide hip fracture database. Individuals ≥ 51 years who filled at least one prescription during the study period comprised the population at risk. Using Rx-Risk as a time-varying exposure variable, relative risk estimates were obtained by a negative binomial model. RESULTS: During 2006-2017, 94,104 individuals sustained a first hip fracture. A higher Rx-Risk was associated with increased risk of hip fracture within all categories of age and sex. Women with the highest Rx-Risk (> 25) had a relative risk of 6.1 (95% confidence interval (CI): 5.4, 6.8) compared to women with Rx-Risk ≤ 0, whereas the corresponding relative risk in women with Rx-Risk 1-5 was 1.4 (95% CI: 1.3, 1.4). Similar results were found in men. Women > 80 years with Rx-Risk 21-25 had the highest incidence rate (514 (95% CI: 462, 566) per 10, 000 person years). The relative increase in hip fracture risk with higher Rx-Risk was most pronounced in the youngest patients aged 51-65 years. CONCLUSIONS: Rx-Risk is a strong predictor of hip fracture in the general outpatient population and may be useful to identify individuals at risk in a clinical setting and in future studies.

The hidden burden of dysmenorrhea among adolescent girls in Palestine refugee camps: a focus on well-being and academic performance.

BACKGROUND: Dysmenorrhea (painful menstruation) is a condition that may have a profound effect on adolescent girls' health status and well-being. It can impede their engagement in daily activities and hamper their regular school attendance. This study aims to explore the relationship between dysmenorrhea, well-being, and academic performance among adolescent girls living in Palestine refugee camps in the West Bank and Jordan. METHODS: We conducted a household survey between June and September 2019, with a total sample of 2737 adolescent girls 15 to 18 years old. Dysmenorrhea severity was assessed using the Working Ability, Location, Intensity, Duration of pain Dysmenorrhea scale (WaLIDD). The WHO-5 scale was used to evaluate the girls' overall well-being. Menstrual academic disruption (MAD) was measured using a self-reported scale. Multiple linear regression models were employed to evaluate the association between dysmenorrhea, well-being, and academic performance. Directed Acyclic Graphs (DAGs) were employed to identify variables for control in regression models. RESULTS: The mean dysmenorrhea score was 6.6 ± 2.6, with 37.9% and 41.2% expressing moderate and severe symptoms, respectively. The mean WHO-5 score was 58.7 ± 25.1, and 34.9% reported a low well-being status. The mean MAD score was 3.1 ± 3.3. 26% reported missing school due to dysmenorrhea, 36% said dysmenorrhea impacted their ability to concentrate, and 39% were unable to study for tests, and complete homework. The first regression analysis showed a reduction of 1.45 units in WHO-5 score for each unit increase in dysmenorrhea. The second regression analysis showed a non-linear increase in MAD score for increasing dysmenorrhea. For each dysmenorrhea score less than 4 (mild) there was a modest increase in MAD scores (coefficient 0.08, p-value = 0.006), and for each dysmenorrhea score above 4 there was a stronger increase in MAD scores (coefficient 0.95, p < 0.001). CONCLUSION: Dysmenorrhea poses significant challenges to the well-being and academic performance of adolescent girls living in Palestine refugee camps. Collaborative efforts and multifaceted approaches are crucial to address dysmenorrhea effectively. This involves research, targeted interventions, culturally sensitive strategies, and fostering a supportive environment that empowers girls to thrive academically and beyond.

BCG vaccination and multiple sclerosis risk: A Norwegian cohort study.

INTRODUCTION: Bacillus Calmette-Guérin (BCG) vaccination induces long-lasting effects on the adaptive and innate immune systems and prevents development of experimental autoimmune encephalomyelitis and possibly also inflammatory disease activity in multiple sclerosis (MS). OBJECTIVE: The objective is to examine if BCG given in early adulthood decreases MS risk. METHODS: From 791,369 (52% females) Norwegians participating in a national tuberculosis screening program from 1963 to 1975, we collected information on BCG vaccination and tuberculosis disease status. Later, MS disease was ascertained through both the Norwegian MS Registry and Biobank and the Norwegian Death Registry. We used logistic regression models to assess the relationship between BCG vaccination and MS risk. RESULTS: In those BCG vaccinated, mean age at vaccination was 15.6 (standard deviation (SD) = 5.5) years. A total of 2862 (65% females) MS cases were retrieved. Overall, we found no association between MS risk and BCG vaccination. Compared to non-BCG-vaccinated individuals with no signs of tuberculosis infection, odds ratio (OR) for MS was 1.00 (95% confidence interval (CI) = 0.80-1.25) in the BCG-vaccinated group. In those not BCG vaccinated because of latent tuberculosis infection, the corresponding OR was 0.86 (95% CI = 0.66-1.13). CONCLUSION: We found no evidence of BCG vaccination or latent tuberculosis infection in young adulthood being linked to MS risk.

Tuberculin responses after BCG vaccination predict amyotrophic lateral sclerosis risk.

Background: T cell infiltration around dying motor neurons is a hallmark of amyotrophic lateral sclerosis (ALS). It is not known if this immune response represents a cause or a consequence of the disease. We aimed to establish whether individual variation in regulation of a T cell driven immune response is associated with long-term ALS risk. Methods: Tuberculin skin test (TST) following BCG vaccination represents a standardized measure of a secondary T cell driven immune response. During a Norwegian tuberculosis screening program (1963-1975) Norwegian citizens born from 1910 to 1955 underwent TST. In those previously BCG vaccinated (median 7 years prior to TST), we related tuberculin skin tests to later ALS disease identified through validated Norwegian health registers. We fitted Cox proportional hazard models to investigate the association between tuberculin reactivity and ALS risk. Results: Among 324,629 participants (52 % women) with median age 22 (IQR 10) years at tuberculosis screening, 496 (50 % women) later developed ALS. Hazard ratio for ALS was 0.74 (95% CI 0.57-0.95) for those who remained TST negative compared to those who mounted a positive TST. The association was strongest when time between BCG immunization and TST was short. The associations observed persisted for more than four decades after TST measurement. Conclusions: Negative TST responses after BCG vaccination is associated with decreased long-term risk for ALS development, supporting a primary role for adaptive immunity in ALS development.

Perinatal exposure to potential endocrine disrupting chemicals and autism spectrum disorder: From Norwegian birth cohort to zebrafish studies.

BACKGROUND: The etiology of autism spectrum disorder (ASD) is multifactorial, involving genetic and environmental contributors such as endocrine-disrupting chemicals (EDCs). OBJECTIVE: To evaluate the association between perinatal exposure to 27 potential EDCs and ASD among Norwegian children, and to further examine the neurodevelopmental toxicity of associated chemicals using zebrafish embryos and larvae. METHOD: 1,199 mothers enrolled in the prospective birth-cohort (HUMIS, 2002-2009) study. Breastmilk levels of 27 chemicals were measured: polychlorinated biphenyls, organochlorine pesticides, polybrominated diphenyl ethers, and perfluoroalkyl substances as a proxy for perinatal exposure. We employed multivariable logistic regression to determine association, utilized elastic net logistic regression as variable selection method, and conducted an in vivo study with zebrafish larvae to confirm the neurodevelopmental effect. RESULTS: A total of 20 children had specialist confirmed diagnosis of autism among 1,199 mother-child pairs in this study. ß-Hexachlorocyclohexane (ß-HCH) was the only chemical associated with ASD, after adjusting for 26 other chemicals. Mothers with the highest levels of ß-HCH in their milk had a significant increased risk of having a child with ASD (OR = 1.82, 95 % CI: 1.20, 2.77 for an interquartile range increase in ln-transformed ß-HCH concentration). The median concentration of ß-HCH in breast milk was 4.37 ng/g lipid (interquartile range: 2.92-6.47), and the estimated daily intake (EDI) for Norwegian children through breastfeeding was 0.03 µg/kg of body weight. The neurodevelopmental and social behavioral effects of ß-HCH were established in zebrafish embryos and larvae across various concentrations, with further analysis suggesting that perturbation of dopaminergic neuron development may underlie the neurotoxicity associated with ß-HCH. CONCLUSIONS: Prenatal exposure to ß-HCH was associated with an increased risk of specialist-confirmed diagnoses of ASD among Norwegian children, and the EDI surpasses the established threshold. Zebrafish experiments confirm ß-HCH neurotoxicity, suggesting dopaminergic neuron disruption as a potential underlying mechanism.

Trajectories of ADHD medication use before, during, and after pregnancy: A population-based study from Norway and Sweden.

PURPOSE: To describe ADHD medication use trajectories around pregnancy in Norway and Sweden. METHODS: We identified pregnancies resulting in births using linked data from birth and prescribed drug registers of Norway (2006-2019, N = 813 107) and Sweden (2007-2018, N = 1 269 146). We restricted to women who filled prescriptions for ADHD medication during pregnancy or in the year before or after. We described exposure as use versus no use, and total amount of drug dispensed in defined daily doses (DDDs). Group-based trajectory modeling was used to identify distinct medication use trajectories. RESULTS: In total, 13 286 women (0.64%) filled a prescription for ADHD medication. We identified four trajectory groups: continuers (5.7%), interrupters (23.8%), discontinuers (49.5%), and late initiators (21.0%). Discontinuers were younger, continuers were older on average. More women continued medication in recent years (2014-2019). Most discontinuers (60.7%) were nulliparous; more initiators and continuers had one or multiple previous births, respectively. Continuers were least likely to live with a partner (65.8%). Discontinuers were least likely (24.7%) and continuers most likely (37.6%) to smoke at the beginning of pregnancy. More continuers used amphetamine derivatives and were most likely to use other psychotropics. On modeling continuers, we identified three dose-trajectory groups which suggested that most women reduced medication dose during pregnancy. CONCLUSIONS: Most pregnant women discontinued or interrupted their ADHD medication during pregnancy, but more continued in recent years. Continuers were more likely to have had previous births, less likely to have lived with a partner, and may have had additional comorbidities warranting the use of other psychotropics.

Pain tolerance after stroke: The Tromsø study.

BACKGROUND: Stroke lesions might alter pain processing and modulation by affecting the widely distributed network of brain regions involved. We aimed to compare pain tolerance in stroke survivors and stroke-free persons in the general population, with and without chronic pain. METHODS: We included all participants of the sixth and seventh wave of the population-based Tromsø Study who had been tested with the cold pressor test (hand in cold water bath, 3°C, maximum time 106 s in the sixth wave and 120 s in the seventh) and who had information on previous stroke status and covariates. Data on stroke status were obtained from the Tromsø Study Cardiovascular Disease Register and the Norwegian Stroke Register. Cox regression models were fitted using stroke prior to study attendance as the independent variable, cold pressor endurance time as time variable and hand withdrawal from cold water as event. Statistical adjustments were made for age, sex, diabetes, hypertension, hyperlipidaemia, body mass index and smoking. RESULTS: In total 21,837 participants were included, 311 of them with previous stroke. Stroke was associated with decreased cold pain tolerance time, with 28% increased hazard of hand withdrawal (hazard ratio [HR] 1.28, 95% CI 1.10-1.50). The effect was similar in participants with (HR 1.28, 95% CI 0.99-1.66) and without chronic pain (HR 1.29, 95% CI 1.04-1.59). CONCLUSIONS: Stroke survivors, with and without chronic pain, had lower cold pressor pain tolerance, with possible clinical implications for pain in this group. SIGNIFICANCE: We found lower pain tolerance in participants with previous stroke compared to stroke-free participants of a large, population-based study. The association was present both in those with and without chronic pain. The results may warrant increased awareness by health professionals towards pain experienced by stroke patients in response to injuries, diseases and procedures.

Time-varying exposure to anti-osteoporosis drugs and risk of first-time hip fracture: a population wide study within the Norwegian Epidemiologic Osteoporosis Studies (NOREPOS).

We investigated the association between bisphosphonate and denosumab use and risk of hip fracture in Norway. These drugs protect against fractures in clinical trials, but their population-level effect is unknown. Our results showed lowered risk of hip fracture for treated women. Treatment of high-risk individuals could prevent future hip fractures. PURPOSE: To investigate whether bisphosphonates and denosumab reduced the risk of first-time hip fracture in Norwegian women when adjusting for a medication-based comorbidity index. METHODS: Norwegian women aged 50-89 in 2005-2016 were included. The Norwegian prescription database (NorPD) supplied data on exposures to bisphosphonates, denosumab, and other drugs for the calculation of the Rx-Risk Comorbidity Index. Information on all hip fractures treated in hospitals in Norway was available. Flexible parametric survival analysis was used with age as time scale and with time-varying exposure to bisphosphonates and denosumab. Individuals were followed until hip fracture or censoring (death, emigration, age 90 years), or 31 December 2016, whichever occurred first. Rx-Risk score was included as a time-varying covariate. Other covariates were marital status, education, and time-varying use of bisphosphonates or denosumab with other indications than osteoporosis. RESULTS: Of 1,044,661 women 77,755 (7.2%) were ever-exposed to bisphosphonate and 4483 (0.4%) to denosumab. The fully adjusted hazard ratios (HR) were 0.95 (95% confidence interval (CI): 0.91-0.99) for bisphosphonate use and 0.60 (95% CI: 0.47-0.76) for denosumab use. Bisphosphonate treatment gave a significantly reduced risk of hip fracture compared with the population after 3 years and denosumab after 6 months. Fracture risk was lowest in denosumab users who had previously used bisphosphonate: HR 0.42 (95% CI: 0.29-0.61) compared with the unexposed population. CONCLUSIONS: In population-wide real-world data, women exposed to bisphosphonates and denosumab had a lower hip fracture risk than the unexposed population after adjusting for comorbidity. Treatment duration and treatment history impacted fracture risk.

Menstrual characteristics and dysmenorrhea among Palestinian adolescent refugee camp dwellers in the West Bank and Jordan: a cross-sectional study.

BACKGROUND: Women and girls experience menstruation throughout their reproductive years. Normal adolescent menstrual cycles gauge current and future reproductive health. Dysmenorrhea (painful menstruation) is the most prevalent menstrual disturbance in adolescents that can be debilitating. This study examines the menstrual characteristics of adolescent girls living in Palestinian refugee camps in the West Bank of the Israeli-occupied Palestinian territory and Jordan, including estimates of dysmenorrhea levels and associated factors. METHODS: A household survey of 15 to 18-year-old adolescent girls was conducted. Trained field workers collected data on general menstrual characteristics and dysmenorrhea level using Working ability, Location, Intensity, Days of pain Dysmenorrhea scale (WaLIDD), in addition to demographic, socio-economic, and health characteristics. The link between dysmenorrhea and other participant characteristics was assessed using a multiple linear regression model. Additionally, data on how adolescent girls cope with their menstrual pain was collected. RESULTS: 2737 girls participated in the study. Mean age was 16.8 ± 1.1 years. Mean age-at-menarche was 13.1 ± 1.2; mean bleeding duration was 5.3 ± 1.5 days, and mean cycle length was 28.1 ± 6.2 days. Around 6% of participating girls reported heavy menstrual bleeding. High dysmenorrhea levels were reported (96%), with 41% reporting severe symptoms. Higher dysmenorrhea levels were associated with older age, earlier age-at-menarche, longer bleeding durations, heavier menstrual flow, skipping breakfast regularly, and limited physical activity patterns. Eighty nine percent used non-pharmacological approaches to ease menstrual pain and 25% used medications. CONCLUSION: The study indicates regular menstrual patterns in terms of length, duration, and intensity of bleeding and a slightly higher age-at-menarche than the global average. However, an alarmingly high prevalence of dysmenorrhea among participants was found that tends to vary with different population characteristics, some of which are modifiable and can be targeted for better menstrual health.This research emphasizes the need for integrated efforts to assist adolescents with menstrual challenges such as dysmenorrhea and irregular periods to achieve informed recommendations and effective actions.

Adjusting for outcome risk factors in immigrant datasets: total or direct effects?

BACKGROUND: When quantifying differences in health outcomes between immigrants and non-immigrants, it is common practice to adjust for observed differences in outcome risk factors between the groups being compared. However, as some of these outcome risk factors may act as mediators on the causal path between the exposure and outcome, adjusting for these may remove effects of factors that characterize the immigrants rather than removing a bias between immigrants and non-immigrants. METHODS: This study investigates the underlying conditions for which adjusting for outcome risk factors in regression models can lead to the estimation of either total or direct effect for the difference in health outcomes between immigrants and non-immigrants. For this investigation, we use modern tools in causal inference to construct causal models that we believe are highly relevant in an immigrant dataset. In these models, the outcome risk factor is modeled either as a mediator, a selection factor, or a combined mediator/selection factor. Unlike mediators, selection factors are variables that affect the probability of being in the immigrant dataset and may contribute to a bias when comparing immigrants and non-immigrants. RESULTS: When the outcome risk factor acts both as a mediator and selection factor, the adjustment for the risk factor in regression models leads to the estimation of what is known as a "controlled" direct effect. When the outcome risk factor is either a selection factor or a mediator alone, the adjustment for the risk factor in regression models leads to the estimation of a total effect or a controlled direct effect, respectively. In all regression analyses, also adjusting for various confounding paths, including mediator-outcome confounding, may be necessary to obtain valid controlled direct effects or total effects. CONCLUSIONS: Depending on the causal role of the outcome risk factors in immigrant datasets, regression adjustment for these may result in the estimation of either total effects or controlled direct effects for the difference in outcomes between immigrants and non-immigrants. Because total and controlled direct effects are interpreted differently, we advise researchers to clarify to the readers which types of effects are presented when adjusting for outcome risk factors in immigrant datasets.

Aryl hydrocarbon receptor activity in human breast milk and cryptorchidism: A case-control study within the prospective Norwegian HUMIS cohort.

BACKGROUND: The etiology of cryptorchidism remains poorly understood. Endocrine disrupting chemicals can impact estrogen signaling by interacting with aryl hydrocarbon receptor (AhR) activity. OBJECTIVE: To evaluate whether AhR activity in breast milk samples is associated with cryptorchidism. METHOD: We conducted a case-control study based on 199 mother-child pairs (n = 91 cases/108 controls) selected from the Norwegian Human Milk Study (2002-2009). We defined cases for cryptorchidism based on maternal reports at 1-, 6-, 12-, and 24- months after birth. Chemically- and biologically stable AhR activity (pg 2,3,7,8-TCDD equivalent (TEQ)/g lipid) was determined by DR- CALUX® assay in the mothers' milk collected at a median of 33 (10th-90th percentile: 18-57) days after delivery. We used multivariate logistic regression to compare AhR activity levels between cases and controls, and linear regression separately, to establish the relationship with the presence of 27 potential EDCs measured in breast milk and AhR activity. RESULTS: The average estimated daily intake (EDI) of dioxin and (dioxin-like (dl)-compounds via breast milk is 33.7 ± 17.9 pg TEQ/kg bodyweight per day among Norwegian children. There were no significant differences in AhR activation in breast milk samples between cases with cryptorchidism and controls. Among the 27 chemicals measured in breast milk, AhR activity was (borderline) significantly associated with all dl-PCBs, three non-dioxin-like (ndl)-PCBs (PCB-74, PCB-180, PCB-194) and two organochlorine pesticides (OCPs; HCB, ß-HCH). No associations between AhR activity and brominated flame retardants (PBDEs) or poly- and perfluoroalkyl substances (PFASs). CONCLUSION: No association between AhR activity and cryptorchidism was found among Norwegian boys. The average EDI of dioxin and dl-compounds in exclusively breastfed Norwegian infants remains above the safety threshold and, therefore requires further reduction measures. Consistent with a possible role in the observed AhR activity, all dl-PCBs were associated with AhR activity whereas the association was null for either PBDEs or PFASs.

The Association of Cold Ambient Temperature With Fracture Risk and Mortality: National Data From Norway-A Norwegian Epidemiologic Osteoporosis Studies (NOREPOS) Study.

Norway is an elongated country with large variations in climate and duration of winter season. It is also a high-risk country for osteoporotic fractures, in particular hip fractures, which cause high mortality. Although most hip fractures occur indoors, there is a higher incidence of both forearm and hip fractures during wintertime, compared with summertime. In a nationwide longitudinal cohort study, we investigated whether cold ambient (outdoor) temperatures could be an underlying cause of this high incidence and mortality. Hospitalized/outpatient forearm fractures (International Classification of Diseases and Related Health Problems, 10th Revision [ICD-10] code S52) and hospitalized hip fractures (ICD-10 codes S72.0-S72.2) from 2008 to 2018 were retrieved from the Norwegian Patient Registry. Average monthly ambient temperatures (degrees Celsius, °C) from the years 2008 to 2018 were provided by the Norwegian Meteorological Institute and linked to the residential area of each inhabitant. Poisson models were fitted to estimate the association (incidence rate ratios [IRRs], 95% confidence intervals [CIs]) between temperature and monthly incidence of total number of forearm and hip fractures. Flexible parametric survival models (hazard ratios [HR], 95% CI) were used to estimate the association between temperature and post-hip fracture mortality, taking the population mortality into account. Monthly temperature ranged from -20.2°C to 22.0°C, with a median of -2.0°C in winter and 14.4°C in summer. At low temperatures (<0°C) compared to ≥0°C, there was a 53% higher risk of forearm fracture (95% CI, 51%-55%) and 21% higher risk of hip fracture (95% CI, 19%-22%), adjusting for age, gender, calendar year, urbanization, residential region, elevation, and coastal proximity. When taking the population mortality into account, the post-hip fracture mortality in both men (HR 1.08; 95% CI, 1.02-1.13) and women (HR 1.09; 95% CI, 1.04-1.14) was still higher at cold temperatures. There was a higher risk of forearm and hip fractures, and an excess post-hip fracture mortality at cold ambient temperatures. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Risk factors for revision surgery due to dislocation within 1 year after 111,711 primary total hip arthroplasties from 2005 to 2019: a study from the Norwegian Arthroplasty Register.

BACKGROUND AND PURPOSE: Dislocation of a hip prosthesis is the 3rd most frequent cause (after loosening and infection) for hip revision in Norway. Recently there has been a shift in surgical practice including preferred head size, surgical approach, articulation, and fixation. We explored factors associated with the risk of revision due to dislocation within 1 year and analyzed the impact of changes in surgical practice. PATIENTS AND METHODS: 111,711 cases of primary total hip arthroplasty (THA) from the Norwegian Arthroplasty Register were included (2005-2019) after primary THA with either 28 mm, 32 mm, or 36 mm femoral heads, or dualmobility articulations. A flexible parametric survival model was used to calculate hazard ratios for risk factors. Kaplan-Meier survival rates were calculated. RESULTS: There was an increased risk of revision due to dislocation with 28 mm femoral heads (HR 2.6, 95% CI 2.0-3.3) compared with 32 mm heads. Furthermore, there was a reduced risk of cemented fixation (HR 0.6, CI 0.5-0.8) and reverse hybrid (HR 0.6, CI 0.5-0.8) compared with uncemented. Also, both anterolateral (HR 0.5, CI 0.4-0.7) and lateral (HR 0.6, CI 0.5-0.7) approaches were associated with a reduced risk compared with the posterior approach. The time-period 2010-2014 had the lowest risk of revision due to dislocation. The trend during the study period was towards using larger head sizes, a posterior approach, and uncemented fixation for primary THA. INTERPRETATION: Patients with 28 mm head size, a posterior approach, or uncemented fixation had an increased risk of revision due to dislocation within 1 year after primary THA. The shift from lateral to posterior approach and more uncemented fixation was a plausible explanation for the increased risk of revision due to dislocation observed in the most recent time-period. The increased risk of revision due to dislocation was not fully compensated for by increasing femoral head size from 28 to 32 mm.

Strong tuberculin response after BCG vaccination is associated with low multiple sclerosis risk: a population-based cohort study.

BACKGROUND: Multiple sclerosis (MS) is characterized by inflammatory lesions in the central nervous system involving pro-inflammatory T-cells. Immune dysregulation is well described in prevalent disease, but it is not known whether this precedes disease development. Bacillus Calmette-Guérin (BCG) vaccination ameliorates MS-like disease in mice. In people vaccinated with BCG, the tuberculin skin test (TST) offers a standardized measure of a T-cell-mediated immune response. We therefore hypothesized that the strength of the TST response after BCG vaccination is associated with subsequent MS risk. METHODS: Using data from a Norwegian tuberculosis screening programme (1963-1975), we designed a population-based cohort study and related the size of TST reactions in individuals previously vaccinated with BCG to later MS disease identified through the Norwegian MS registry. We fitted Cox proportional hazard models and flexible parametric survival models to investigate the association between TST reactivity, MS risk and its temporal relationship. RESULTS: Among 279 891 participants (52% females), 679 (69% females) later developed MS. Larger TST reactivity was associated with decreased MS risk. The hazard ratio for MS per every 4-mm increase in skin induration size was 0.86 (95% confidence interval 0.76-0.96) and similar between sexes. The strength of the association persisted for >30 years after the TST. CONCLUSION: A strong in vivo vaccine response to BCG is associated with reduced MS risk >30 years later. The immunological mechanisms determining TST reactivity suggest that skewed T-cell-mediated immunity precedes MS onset by many decades.

Lipid and lipoprotein concentrations during pregnancy and associations with ethnicity.

BACKGROUND: To describe ethnic differences in concentrations of lipids and lipoproteins, and their changes, during pregnancy to postpartum. METHODS: This was a population-based cohort study conducted in primary antenatal care in Norway. The participants (n = 806) were healthy, pregnant women, 59% were ethnic minorities. Outcomes were triglycerides, total cholesterol, HDL- and LDL-cholesterol, analysed from fasting blood samples drawn at gestational age (weeks) 15, 28 and 14 weeks postpartum. We performed linear regression models and linear mixed models to explore the total effect of ethnicity on the outcomes, adjusting for gestational age /week postpartum, maternal age and education. The analyses are corrected for multiple testing using the Bonferroni correction. RESULTS: At gestational age 15, triglyceride concentrations were lower in women of African origin (1.03 mmol/mol (95% CI: 0.90, 1.16)) and higher in women of South Asian (primarily Pakistan and Sri Lanka) origin (1.42 mmol/mol (1.35, 1.49)) and East Asian (primarily Vietnam, Philippines and Thailand) origin (1.58 mmol/mol (1.43, 1.73)) compared with Western Europeans (1.26 mmol/mol (1.20, 1.32)). Women of Asian and African origin had a smaller increase in triglycerides, LDL- and total cholesterol from gestational age 15 to 28. At gestational age 28, LDL-cholesterol levels were lowest among East Asians (3.03 mmol/mol (2.72, 3.34)) compared with Western Europeans (3.62 mmol/mol (3.50, 3.74)). Triglycerides and HDL-cholesterol were lower postpartum than at gestational age 15 in all groups, but the concentration of LDL-cholesterol was higher, except in Africans. South and East Asian women had lower HDL-cholesterol and higher triglycerides postpartum, while African women had lower triglycerides than Western Europeans. CONCLUSION: We found significant differences in the concentrations of lipids and lipoproteins and their changes during pregnancy and the early postpartum period related to ethnic origin.

Anti-androgenic compounds in breast milk and cryptorchidism among Norwegian boys in the HUMIS birth cohort.

The prevalence of cryptorchidism has increased over the past decades, yet its origins remain poorly understood. Testis descent is dependent on androgens and likely affected by endocrine disrupting compounds (EDCs), targeting the androgen receptor (AR). We investigated the association between anti-androgenic activity, not derived from natural hormones, in maternal breast milk and impaired testis descent among boys. We performed a case-control study based on 199 breast milk samples from 94 mothers of cryptorchid boys and 105 random non-cryptorchid boys participating in the Norwegian HUMIS (Human Milk Study) cohort. For each participant, apolar, and polar fractions were extracted, and combined to reconstitute a mixture. Anti-androgenic activity was measured in all three fractions using the human cell-based in vitro anti-AR CALUX® assay and expressed in µg of flutamide equivalent, a well-known antiandrogen. Results from fraction analyses were compared among boys with cryptorchidism and controls using multiple logistic regression, controlling for appropriate confounders identified using a directed acyclic graph. Children's daily exposure to anti-androgenic EDCs through breastfeeding was estimated to 78 µg flutamide eq./kg of body weigh/day. The activity was higher in the polar fraction (1.48 ± 1.37 µg flutamide eq./g of milk) mainly representing non-persistent chemicals, in contrast to other fractions. However, the activity in the polar extracts was decreased when in mixtures with the apolar fraction, indicating synergistic interactions. No significant difference in the activity was observed according to cryptorchid status for polar, apolar or mixed breast milk fractions. The study showed anti-androgenic activity in nearly all human milk samples, and at levels higher than the advisory threshold. However, no significant association was observed between cryptorchidism and antiandrogenic activity measured in either polar, apolar, or mixture fractions derived from breast milk.

Childhood abuse and its association with adults' mental health problems: a cross-sectional study among men and women in the Yangon Region of Myanmar.

OBJECTIVES: To estimate the prevalence of emotional, physical and sexual childhood abuse, and symptoms of post-traumatic stress disorder (PTSD) and to examine the association between childhood abuse and adult mental health problems, including mental distress and PTSD symptoms. DESIGN: A community-based cross-sectional study was conducted. Childhood abuse was assessed with the NorVold Abuse Questionnaire, and mental distress and symptoms of PTSD were measured using the Hopkins Symptom Checklist 10 and the Impact of Event Scale-Revised, respectively. The Wald test and multiple linear regression analysis were applied for testing differences between proportions and the association between childhood abuse and adult mental health outcomes, respectively. SETTING: Urban and rural areas of the Yangon Region, Myanmar. PARTICIPANTS: A total of 2377 men and women aged 18-49 years were included. Institutionalised people, monks, nuns and individuals deemed too ill physically and/or mentally to participate were excluded. RESULTS: Overall, 21.1% (95% CI 18.8 to 23.6) reported any form of childhood abuse, 10.4% (95% CI 8.9 to 12.4) physical abuse, 10.4% (95% CI 8.8 to 12.2) emotional abuse and 7.3% (95% CI 5.7 to 9.3) sexual abuse. Childhood abuse was more common in women (29.8%) than in men (12.4%). The prevalence of PTSD symptoms in the total sample was 6.6%. After adjusting for confounding variables, positive associations were found between childhood abuse with adult mental distress and PTSD symptoms among women and older men. CONCLUSIONS: Childhood abuse is prevalent among both men and women in the Yangon Region of Myanmar and associated with adult mental health problems. Approximately 7% of people report PTSD symptoms. It should prompt local health professionals and policy makers to establish prevention programmes to eliminate violence against children and to organise services for victims of childhood abuse. Care should be taken in generalising findings for less populated areas.