Selenium concentration and cardiovascular disease risk: Mendelian randomization study

Background/Introduction

Selenium has been associated with cardiovascular disease (CVD) risk in observational studies; however, the causality of the association remains unestablished.

Purpose

To examine the associations of selenium concentrations with 15 CVDs using Mendelian randomization analysis.

Methods

Genetic variants significantly associated with concentrations of toenail and blood (TAB) and blood selenium in mild linkage disequilibrium (r2 <0.3) were used as instrumental variables. Summary-level data for 15 CVDs were obtained from the UK Biobank study (n=367,561), FinnGen study (n=218,792), and six international consortia. The inverse variance weighted method accounting for linkage disequilibrium was used to estimate the associations. Results for one outcome from different sources were combined using the fixed effect meta-analysis method. Bonferroni correction was used to account for multiple testing, and associations with P value ≤0.003 (0.05 / 15 outcomes) were described as significant. Associations with P value between ≤0.05 and >0.003 were regarded as suggestive associations.

Results

Genetically predicted concentrations of TAB selenium were not significantly associated with the risk of the 15 CVDs. However, there were suggestive associations of genetically predicted higher concentrations of TAB selenium with increased risk of atrial fibrillation and peripheral artery disease. The odds ratio per one-unit increase in log-transformed concentrations of TAB selenium was 1.07 (95% confidence interval, 1.01–1.12; P=0.019) for atrial fibrillation and 1.20 (95% confidence interval, 1.05–1.38; P=0.008) for peripheral artery disease. We observed no associations between genetically predicted blood selenium concentrations and risk of the 15 CVDs.

Conclusions

Genetically predicted higher concentrations of TAB or blood selenium were not associated with a lower risk of CVD, which suggests that high selenium status may not prevent CVD development. The suggestive positive associations of TAB selenium with atrial fibrillation and peripheral artery disease warrants verification.

Funding Acknowledgement

Type of funding sources: None.

The alarmins high mobility group box protein 1 and S100A8/A9 display different inflammatory profiles after acute knee injury

OBJECTIVE

To compare the concentrations of high mobility group box 1 protein (HMGB1) and S100A8/A9 in synovial fluid between patients with knee injuries and osteoarthritis (OA), and knee healthy subjects. To investigate associations of alarmin levels with different joint injuries and with biomarkers of inflammation, Wnt signaling, complement system, bone and cartilage degradation.

METHODS

HMGB1 and S100A8/A9 were measured in synovial fluid by immunoassays in patients with knee injuries, with OA and from knee healthy subjects, and were related to time from injury and with biomarkers obtained from previous studies. Hierarchical cluster and enrichment analyses of biomarkers associated to HMGB1 and S100A8/A9 were performed.

RESULTS

The synovial fluid HMGB1 and S100A8/A9 concentrations were increased early after knee injury; S100A8/A9 levels were negatively associated to time after injury and was lower in the old compared to recent injury group, while HMGB1 was not associated to time after injury. The S100A8/A9 levels were also increased in OA. The initial inflammatory response was similar between the alarmins, and HMGB1 and S100A8/A9 shared 9 out of 20 enriched pathways. The alarmins displayed distinct response profiles, HMGB1 being associated to cartilage biomarkers while S100A8/A9 was associated to proinflammatory cytokines.

CONCLUSIONS

HMGB1 and S100A8/A9 are increased as an immediate response to knee trauma. While they share many features in inflammatory and immunoregulatory mechanisms, S100A8/A9 and HMGB1 are associated to different downstream responses, which may have impact on the OA progression after acute knee injuries.

Endurance training increases the risk of atrial fibrillation in women: a matched-cohort study

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): This work was supported by research grants from Kvinnor och Hälsa and The Swedish Research Council for Sport Science (to Nikola Drca).

Objective

Previous studies have found that vigorous physical activity, mainly related to endurance sport participation, increases the risk of atrial fibrillation (AF) in men. However, it remains unclear whether vigorous physical activity also influences the risk of AF in women. We aimed to examine whether endurance sport participation may affect AF risk in women.

Methods

We conducted a matched-cohort study of top Swedish female endurance athletes (n=228 marathon runners, cyclist, and 10 000-meters track runners) active between 1979-1991 and reference individuals (n=1 368) from the general population individually matched by sex, year of birth, and area of living with a 6:1 ratio to the female athletes. The athlete cohort was created by combining all Swedish women who ran the Stockholm Marathon faster than 3.25 hours in any of the races between 1979 and 1991 with all Swedish women competing in the Swedish athletic national championship in 10 000-meter track running and the top-ranked Swedish bicyclist during the same period. Participants were followed up from study entry until AF diagnosis, death, emigration, or December 31, 2017, whichever occurred first. We used the Swedish National Patient Register to determine whether the participants were diagnosed with AF and other covariables. Cox proportional hazards regression models were used for analysis.

Results

Baseline characteristics are presented in Table 1. Mean age at study entry was 32 (SD ± 8.5) years. During follow-up (mean 28.8 years; SD ± 4.4), 33 cases of AF were diagnosed, including 10 (4.4%) among athletes and 23 (1.7%) among references. Endurance training was associated with an increased AF risk (Figure 1). The hazard ratio for female athletes compared with the reference population was 2.56 (95% confidence interval 1.22 to 5.37) in the univariable model and 3.67 (95% confidence interval 1.71 to 7.87) after adjustment for hypertension.

Conclusion

High level of endurance sport training is associated with an increased risk of AF in women.

Cardiovascular risk factors and lifestyle behaviours in relation to longevity: a Mendelian randomization study

BACKGROUND

The American Heart Association introduced the Life's Simple 7 initiative to improve cardiovascular health by modifying cardiovascular risk factors and lifestyle behaviours. It is unclear whether these risk factors are causally associated with longevity.

OBJECTIVES

This study aimed to investigate causal associations of Life's Simple 7 modifiable risk factors, as well as sleep and education, with longevity using the two-sample Mendelian randomization design.

METHODS

Instrumental variables for the modifiable risk factors were obtained from large-scale genome-wide association studies. Data on longevity beyond the 90^th survival percentile were extracted from a genome-wide association meta-analysis with 11,262 cases and 25,483 controls whose age at death or last contact was ≤ the 60^th survival percentile.

RESULTS

Risk factors associated with a lower odds of longevity included the following: genetic liability to type 2 diabetes (OR 0.88; 95% CI: 0.84;0.92), genetically predicted systolic and diastolic blood pressure (per 1-mmHg increase: 0.96; 0.94;0.97 and 0.95; 0.93;0.97), body mass index (per 1-SD increase: 0.80; 0.74;0.86), low-density lipoprotein cholesterol (per 1-SD increase: 0.75; 0.65;0.86) and smoking initiation (0.75; 0.66;0.85). Genetically increased high-density lipoprotein cholesterol (per 1-SD increase: 1.23; 1.08;1.41) and educational level (per 1-SD increase: 1.64; 1.45;1.86) were associated with a higher odds of longevity. Fasting glucose and other lifestyle factors were not significantly associated with longevity.

CONCLUSION

Most of the Life's Simple 7 modifiable risk factors are causally related to longevity. Prevention strategies should focus on modifying these risk factors and reducing education inequalities to improve cardiovascular health and longevity.

FRI0411 SAFETY, TOLERABILITY, PHARMACOKINETICS AND PHARMACODYNAMICS IN HEALTHY MALE JAPANESE SUBJECTS OF THE ADAMTS-5 INHIBITOR S201086/GLPG1972, A POTENTIAL NEW TREATMENT IN OA

Background:

The disintegrin and metalloproteinase with thrombospondin motifs-5 (ADAMTS-5) is a key enzyme in OA (Verma P,et al.J Cell Biochem 2011;112:3507-14). In preclinical models of OA, S201086, a potent and selective ADAMTS-5 inhibitor, protects from cartilage degradation (Clement-Lacroix,et al.Osteoarthritis Cartilage 2017;25:S58). Therefore, S201086 is co-developed by Servier and Galapagos (GLPG1972) as a potential new treatment in OA.

Objectives:

This phase I study was to assess and compare the safety, tolerability, pharmacokinetics and pharmacodynamics of S201086 in healthy male Japanese and Caucasian subjects.

Methods:

Six ascending single doses of S201086 (50 to 1500 mg) were administered orally as tablets in fasting conditions in 6 groups of 8 Japanese subjects (aged 20-45 years) and 3 ascending multiple doses (300, 600 or 1050 mg/day for 14 days) were administered orally as tablets in fed conditions in 3 groups of 8 Japanese subjects. Additionally, 2 cohorts of 8 Caucasian subjects received either a single oral dose of 300 mg or repeated oral dose of 300 mg once daily for 14 days. In each group, 6 subjects received S201086 and 2 placebo. Plasma was collected at several time points for the quantification of S201086 by LC-MS/MS. Plasma pharmacokinetic parameters were calculated via non-compartmental analysis using Phoenix® WinNonlin® software. Pharmacodynamics was assessed by measurement of the aggrecan ARGS neoepitope levels in serum by ELISA.

Results:

No serious adverse drug reactions were observed after administration of single and multiple ascending doses of S201086 in either Japanese or Caucasian subjects. Most adverse events were of mild to moderate intensity and were resolved by the end of the study. Following single administration to Japanese subjects, Cmax and AUC increased proportionally with doses from 50 to 600 mg and slightly less than dose-proportionally from 600 to 1500 mg, consistent with what was previously observed in the first in-human study in healthy Caucasian subjects (van der Aar E,et al.Osteoarthritis Cartilage 2018;26:S310). In Japanese subjects, after 14-days administration, a limited 1.2- to 1.4-fold accumulation was observed on both Cmax and AUC at Day14 as compared to Day1, and the steady-state exposure increased dose-proportionally within the 300-1050 mg dose range. Taking the inter-subject variability into account, no difference was observed in Cmax and AUC between Caucasian and Japanese subjects after single administrations of 300 mg and repeated administrations of 300 mg once daily for 14 days. The serum ARGS neoepitope levels decreased between baseline and last day of treatment for S201086-treated subjects but not for subjects receiving placebo. This decrease was similar for the 3 tested doses in Japanese subjects and was significant as compared to the placebo-treated subjects.

Table.

Comparison of ARGS concentration relative change from baseline to last day of treatment according to dose in Japanese participants

S 201086 300 mg (N = 6)S 201086 600 mg (N = 6)S 201086 1050 mg (N = 6)Placebo (N = 6)Descriptive Statistics(D14 pre-dose – Baseline) / Baselinen6646Mean ± SD-42.67 ± 8.81-53.70 ± 6.50-54.11 ± 5.2013.35 ± 16.53Statistical analysisE (SE)56.01 (6.156)67.04 (6.156)67.45 (6.883)95% CI43.08; 68.9554.11; 79.9752.99; 81.91p-value< 0.0001< 0.0001< 0.0001

Conclusion:

S201086 was shown to be safe and well-tolerated in Japanese and Caucasian healthy male subjects with a suitable PK profile and a significant decrease of the ARGS neoepitope, indicating target engagement. A global Phase 2 study to evaluate the efficacy of S201086 in patients with knee OA is ongoing (NCT03595618).

Disclosure of Interests:

Agnès Lalande Employee of: Institut de Recherches Internationales Servier, Nadya KUZNIATSOVA-MOUCHETTE Employee of: Institut de Recherches Internationales Servier, Florian CHASSEREAU Employee of: Institut de Recherches Internationales Servier, Julia GERONIMI Employee of: Institut de Recherches Internationales Servier, Katy Bernard Employee of: Institut de Recherches Internationales Servier, Staffan Larsson: None declared, André Struglics: None declared, Stefan Lohmander: None declared, Maria Pueyo Employee of: Institut de Recherches Internationales Servier

Interleukin-1 receptor antagonist, interleukin-2 receptor alpha subunit and amyotrophic lateral sclerosis

BACKGROUND AND PURPOSE

To clarify the causal associations of interleukin-1 receptor antagonist (IL-1ra) and interleukin-2 receptor alpha subunit (IL-2rα) with the risk of amyotrophic lateral sclerosis (ALS).

METHODS

A two-sample Mendelian randomization study design was employed. Single-nucleotide polymorphisms associated with IL-1ra (n = 2) and IL-2rα (n = 1) at the genome-wide significance level were used as unbiased instrumental variables. Summary-level data for ALS were obtained from Project MinE, an international collaboration consortium with 12 577 ALS cases and 23 475 controls of European descent.

RESULTS

Genetic predisposition to higher levels of IL-1ra was significantly associated with lower odds of ALS. For a 1-SD increase of circulating IL-1ra levels, the odds ratio of ALS was 0.64 (95% confidence intervals, 0.46-0.88; P = 0.005). There was a borderline inverse association between IL-2rα levels and ALS (odds ratio, 0.91; 95% confidence intervals, 0.83-1.00; P = 0.058).

CONCLUSIONS

Interleukin-1 receptor antagonist levels were inversely associated with ALS, suggesting that interleukin-1 inhibitors may lower the risk of this always fatal disease. The role of IL-2rα levels in ALS needs further verification in causal inference studies with larger sample sizes.

Molecular and imaging biomarkers of local inflammation at 2 years after anterior cruciate ligament injury do not associate with patient reported outcomes at 5 years

OBJECTIVE

To estimate the association between molecular or imaging inflammatory biomarkers at 2 years after anterior cruciate ligament (ACL) injury and patient-reported outcomes at 5 years.

METHODS

For 116 ACL-injured patients, molecular biomarkers of inflammation (synovial fluid and serum cytokines) and Hoffa- and effusion-synovitis as visualized on magnetic resonance imaging (MRI) were assessed 2 years post-injury. Knee injury and Osteoarthritis Outcome Score (KOOS) and SF-36 were assessed at 2 and 5 years. We used multiple imputation to handle biomarker values that were below the level of detection or missing, and linear regression for statistical analyses.

RESULTS

None of the synovial fluid cytokines or imaging biomarkers of inflammation at 2 years were associated with any of the patient-reported outcomes at 5 years. With each log10 unit higher of serum tumor necrosis factor concentration the knee-related quality of life of KOOS was increased (i.e., better outcome) by 35 (95% confidence interval 7 to 63) points. No other serum biomarker measured at 2 years was associated with patient-reported outcome at 5 years.

CONCLUSION

Local joint inflammation assessed by biomarkers in synovial fluid and Hoffa- and effusion-synovitis on MRI at 2 years after an ACL injury did not associate with patient-reported outcomes at 5 years. Thus, chronic inflammation in the ACL-injured knee, as reflected by the biomarkers studied here, seems not to be a key determinant for the long-term patient-reported outcomes.

Patient-reported Outcome in Surgically Treated Pelvic Ring Injuries at 5 Years Post-surgery

BACKGROUND AND AIMS

Long-term prospective data on patient-reported outcome after surgical treatment of pelvic ring injuries are scarce. This study aimed at describing results at 5 years post-surgery using validated outcome measures.

PATIENTS AND METHODS

Patients admitted for surgical treatment of pelvic ring injuries were prospectively included and asked to report their outcome at 1, 2 and 5 years post-surgery using two patient-reported outcome measures: the generic Short-Form 36 and the condition-specific pelvic discomfort index. Data were evaluated using mixed-effects linear models.

RESULTS

There were 108 patients (68 males and 40 females), mean age 38 years. Injury type according to the AO/OTA-classification was B-type in 68 patients and C-type in 40 patients. No domain of the Short-Form 36 reached norm values at 5 years post-surgery. Females reported a worse outcome than males concerning general health (p < 0.01) at 5 years. Recovery of physical function (p < 0.01), mental health (p = 0.04), and pain (p = 0.01) was observed for males at 5 years compared to earlier assessments, while females on the contrary described more pain at this time-point (p = 0.03). Mean pelvic discomfort index at 5 years was 27, indicating moderate residual pelvic discomfort overall. Males reported less pelvic discomfort than females at 5 years (p = 0.02) and improved when compared to results at 2 years (p = 0.02), while females did not. Influence of age, fracture type, and presence of associated injuries on patient-reported outcome was limited.

CONCLUSION

Surgically treated pelvic ring injuries are associated with long-standing negative effects on patient-reported outcome. Males report a better outcome than females at 5 years post-surgery.

Abstract P1-08-01: Withdrawn

This abstract was withdrawn by the authors.

Citation Format: Schoemaker MJ, Nichols HB, Wright LB, Brook MN, Jones ME, O'Brien KM, Adami H-O, Baglietto L, Bernstein L, Bertrand KA, Boutron-Ruault M-C, Chen Y, Connor AE, Dorronsoro M, Dossus L, Eliassen AH, Giles GG, Gram IT, Hankinson SE, Kaaks R, Key TJ, Kirsh VA, Kitahara CM, Koh W-P, Larsson SC, Linet MS, Ma H, Masala G, Merritt MA, Milne RL, Overvad K, Ozasa K, Palmer JR, Riboli E, Rohan TE, Sadakane A, Sund M, Tamimi RM, Trichopoulou A, Ursin G, Van Gils CH, Visvanathan K, Weiderpass E, Willett WC, Wolk A, Yuan J-M, Zeleniuch-Jacquotte A, Sandler DP, Swerdlow AJ. Withdrawn [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-08-01.

Unresolved Gamma-Ray Sky through its Angular Power Spectrum

The gamma-ray sky has been observed with unprecedented accuracy in the last decade by the Fermi -large area telescope (LAT), allowing us to resolve and understand the high-energy Universe. The nature of the remaining unresolved emission [unresolved gamma-ray background (UGRB)] below the LAT source detection threshold can be uncovered by characterizing the amplitude and angular scale of the UGRB fluctuation field. This Letter presents a measurement of the UGRB autocorrelation angular power spectrum based on eight years of Fermi-LAT Pass 8 data products. The analysis is designed to be robust against contamination from resolved sources and noise systematics. The sensitivity to subthreshold sources is greatly enhanced with respect to previous measurements. We find evidence (with ∼3.7σ significance) that the scenario in which two classes of sources contribute to the UGRB signal is favored over a single class. A double power law with exponential cutoff can explain the anisotropy energy spectrum well, with photon indices of the two populations being 2.55±0.23 and 1.86±0.15.

How do macro-level structural determinants affect inequalities in mental health? - a systematic review of the literature

BACKGROUND

In Europe and elsewhere there is rising concern about inequality in health and increased prevalence of mental ill-health. Structural determinants such as welfare state arrangements may impact on levels of mental health and social inequalities. This systematic review aims to assess the current evidence on whether structural determinants are associated with inequalities in mental health outcomes.

METHODS

We conducted a systematic review of quantitative studies published between 1996 and 2017 based on search results from the following databases Medline, Embase, PsychInfo, Web of Science, Sociological Abstracts and Eric. Studies were included if they focused on inequalities (measured by socio-economic position and gender), structural determinants (i.e. public policies affecting the whole population) and showed a change or comparison in mental health status in one (or more) of the Organisation for Economic Cooperation and Development (OECD) countries. All studies were assessed for inclusion and study quality by two independent reviewers. Data were extracted and synthesised using narrative analysis.

RESULTS

Twenty-one articles (17 studies) met the inclusion criteria. Studies were heterogeneous with regards to methodology, mental health outcomes and policy settings. More comprehensive and gender inclusive welfare states (e.g. Nordic welfare states) had better mental health outcomes, especially for women, and less gender-related inequality. Nordic welfare regimes may also decrease inequalities between lone and couple mothers. A strong welfare state does not buffer against socio-economic inequalities in mental health outcomes. Austerity measures tended to worsen mental health and increase inequalities. Area-based initiatives and educational policy are understudied.

CONCLUSION

Although the literature on structural determinants and inequalities in mental health is limited, our review shows some evidence supporting the causal effects of structural determinants on mental health inequalities. The lack of evidence should not be interpreted as lack of effect. Future studies should apply innovative methods to overcome the inherent methodological challenges in this area, as structural determinants potentially affect both levels of mental health and social inequalities.

Enhanced ventricular-arterial coupling during a 2-year physical activity programme in patients with rheumatoid arthritis: a prospective substudy of the physical activity in rheumatoid arthritis 2010 trial

OBJECTIVE

To establish how guided physical activity in patients with rheumatoid arthritis (RA) without known cardiovascular disease affected vascular and cardiac function, and how these two entities were prospectively interconnected in this patient group.

METHODS

Prospective substudy of 29 participants in the Physical Activity in RA (PARA) 2010 trial. All subjects were examined at baseline, at year 1 and 2 with measures of pulse wave velocity and arterial augmentation index, as well as echocardiographic evaluation of diastolic parameters and ventricular-arterial coupling. Muscle strength and aerobic exercise capacity were assessed at baseline and yearly. All participants performed physiotherapist-guided aerobic and muscle strength exercise during 2 years and were reminded through SMS to report physical activity progress.

RESULTS

This cohort of patients with RA exhibited increased vascular stiffness despite normal blood pressure. At baseline, lower muscle strength was associated with increased vascular stiffness (β = 0.68; P = 0.004), whereas lower aerobic working capacity was associated with left ventricular diastolic dysfunction (β = 0.85; P = 0.03). There was a significant positive correlation between vascular stiffness and diastolic dysfunction at baseline (R²  = 0.64) and for the changes in those parameters observed during 2 years of guided physical activity. Finally, a significant improvement in ventricular-arterial coupling was observed after exercise (P < 0.001).

CONCLUSION

These results indicate that although differentially associated with physical capacity parameters, improved vascular stiffness and improved diastolic dysfunction are interrelated, and that an optimization of the ventricular-arterial coupling may contribute to the beneficial effects of physical activity in patients with RA.

Coffee, tea, and caffeine intake and amyotrophic lateral sclerosis mortality in a pooled analysis of eight prospective cohort studies

BACKGROUND AND PURPOSE

Caffeine is associated with a lower risk of some neurological diseases, but few prospective studies have investigated caffeine intake and risk of amyotrophic lateral sclerosis (ALS) mortality. We therefore determined associations between coffee, tea and caffeine intake, and risk of ALS mortality.

METHODS

We conducted pooled analyses of eight international, prospective cohort studies, including 351 565 individuals (120 688 men and 230 877 women). We assessed coffee, tea and caffeine intake using validated food-frequency questionnaires administered at baseline. We used Cox regression to estimate study- and sex-specific risk ratios and 95% confidence intervals (CI) for ALS mortality, which were then pooled using a random-effects model. We conducted analyses using cohort-specific tertiles, absolute common cut-points and continuous measures of all exposures.

RESULTS

During follow-up, 545 ALS deaths were documented. We did not observe statistically significant associations between coffee, tea or caffeine intake and risk of ALS mortality. The pooled multivariable risk ratio (MVRR) for ≥3 cups per day vs. >0 to <1 cup per day was 1.04 (95% CI, 0.74-1.47) for coffee and 1.17 (95% CI, 0.77-1.79) for tea. The pooled MVRR comparing the highest with the lowest tertile of caffeine intake (mg/day) was 0.99 (95% CI, 0.80-1.23). No statistically significant results were observed when exposures were modeled as tertiles or continuously.

CONCLUSIONS

Our results do not support associations between coffee, tea or total caffeine intake and risk of ALS mortality.

Changes in synovial fluid and serum concentrations of cartilage oligomeric matrix protein over 5 years after anterior cruciate ligament rupture: an exploratory analysis in the KANON trial

OBJECTIVE

To monitor longitudinal changes of cartilage oligomeric matrix protein (COMP) in synovial fluid (sf) and serum (s) over 5 years after acute anterior cruciate ligament (ACL) rupture, and to compare results from two commercial COMP immunoassays.

DESIGN

Bio-fluids were collected from 121 patients on six occasions over 5 years after acute ACL injury, and from 25 knee healthy reference subjects. Concentrations of sf- and sCOMP were measured by AnaMar (sCOMP-Ana) and by BioVendor (sf- and sCOMP-Bio) immunoassays; other biomarkers were previously assessed. We used ANCOVA for group comparisons and linear mixed models for associations between biomarkers over 5-years with P < 0.05 considered a statistically significant difference or association.

RESULTS

Compared to the reference group, sfCOMP-Bio concentrations were 2-fold elevated within 6 weeks after ACL injury and remained elevated 5 years thereafter, whereas sCOMP-Bio and sCOMP-Ana concentrations were no different from reference levels at any time point. Over the 5-year period, there was an association between sCOMP-Bio and sCOMP-Ana concentrations, although neither sCOMP-Bio nor sCOMP-Ana associated with sfCOMP-Bio. sfCOMP-Bio associated with SF ARGS-aggrecan, urine type I and II collagens (uNTX-I and uCTX-II) and SF cytokines, while sCOMP-Bio associated inversely with uCTX-II, uNTX-I and SF cytokines.

CONCLUSION

The local process after an acute ACL injury generates increased SF COMP concentrations in the injured knee up to 5 years after injury. This response is not detected in serum. Discrepancies in associations between sCOMP measured by BioVendor and AnaMar immunoassays with other biomarkers indicate differences in detected COMP fragments.

Coffee consumption and risk of aortic valve stenosis: A prospective study

BACKGROUND AND AIMS

Coffee contains many biologically active compounds with potential adverse or beneficial effects on the cardiovascular system. Whether coffee consumption is associated with the risk of aortic valve stenosis (AVS) is unknown. The purpose of this study was therefore to examine the association between coffee consumption and AVS incidence.

METHODS AND RESULTS

This prospective study included 71 178 men and women who provided information on their coffee consumption through a questionnaire at baseline. Incident cases of AVS were identified through linkage with the Swedish National Patient and Cause of Death Registers. During a mean follow-up of 15.2 years, 1295 participants (777 men and 518 women) were diagnosed with AVS. Coffee consumption was positively associated with risk of AVS in a dose-response manner after adjustment for age, sex, smoking, and other risk factors (P-trend = 0.005). The multivariable hazard ratios were was 1.11 (95% confidence interval 1.04-1.19) per 2 cups/day increase of coffee consumption and 1.65 (95% confidence interval 1.10-2.48) when comparing the highest (≥6 cups/day) with the lowest (<0.5 cup/day) category of coffee consumption. The association was not modified by other risk factors.

CONCLUSIONS

This study provides novel evidence that high coffee consumption is associated with an increased risk of AVS.

Dickkopf-related protein 1 and gremlin 1 show different response than frizzled-related protein in human synovial fluid following knee injury and in patients with osteoarthritis

OBJECTIVE

To explore the involvement of the wingless-type MMTV integration site (WNT) and bone morphogenetic protein (BMP) antagonists dickkopf-related protein 1 (DKK1), frizzled-related protein (FRZB) and gremlin 1 (GREM1) in knee injury and osteoarthritis (OA).

DESIGN

The antagonists were immunoassayed in synovial fluid from a cross-sectional cohort of nine knee healthy reference subjects, patients with recent (0-77 days, n = 158) or old (1-37 years, n = 50) knee injuries, and OA (n = 22). Cartilage (ARGS-aggrecan, cartilage oligomeric matrix protein and C2C type II collagen) and other biomarkers were assessed in synovial fluid in a subset of samples. Statistical analysis was by Kendall's tau (τ) correlation, Mann-Whitney U test, and linear regression analysis.

RESULTS

Compared to references, median concentration of GREM1 (but not DKK1 and FRZB) was elevated 1.5-fold immediately after injury, and FRZB was reduced 1000-folds in OA. All three antagonists decreased with increasing time after injury as well as with increasing age, but the temporal change after injury was less accentuated for FRZB (peaked 8-22 days after injury) compared to that of DKK1 and GREM1 (peaked immediately after injury). In the recent injury group, there was a correlation between GREM1 and DKK1 (τ = 0.172); FRZB concentrations correlated with concentrations of cartilage biomarkers (τ between 0.257 and 0.369), while DKK1 and GREM1 were inversely correlated (τ between -0.177 and -0.217) with these markers.

CONCLUSIONS

Our results indicate separate roles for the antagonists, where DKK1 and GREM1 had similarities in response to injury and in OA, with a different response for FRZB.

Alcohol consumption, cigarette smoking and incidence of aortic valve stenosis

BACKGROUND

Alcohol consumption and cigarette smoking are modifiable lifestyle factors with important impact on public health. It is unclear whether these factors influence the risk of aortic valve stenosis (AVS).

OBJECTIVE

To investigate the associations of alcohol consumption and smoking, including smoking intensity and time since cessation, with AVS incidence in two prospective cohorts.

METHODS

This analysis was based on data from the Swedish Mammography Cohort and the Cohort of Swedish Men, comprising 69 365 adults without cardiovascular disease at baseline. Participants were followed for AVS incidence and death by linkage to the Swedish National Patient and Causes of Death Registers. Hazard ratios (HR) with 95% confidence intervals (CI) were estimated by Cox proportional hazards regression.

RESULTS

Over a mean follow-up of 15.3 years, 1249 cases of AVS (494 in women and 755 in men) were recorded. Compared with never drinkers of alcohol (lifelong abstainers), the risk of AVS was significantly lower in current light drinkers (1-6 drinks per week [1 drink = 12 g alcohol]; multivariable HR 0.82; 95% CI: 0.68-0.99). The risk of AVS increased with increasing smoking intensity. Compared with never smokers, the HR was 1.46 (95% CI: 1.16-1.85) in current smokers of ≥30 pack-years. Former smokers who had quit smoking 10 or more years previously had similar risk for AVS as never smokers.

CONCLUSIONS

This study suggests that current light alcohol consumption is associated with a lower risk of AVS, and indicates that the association between smoking and AVS risk is reversible.

Clinical Outcome after Plaster Cast Fixation for 10 Days Versus 1 Month in Reduced Distal Radius Fractures: A Prospective Randomized Study

Introduction:

This study aimed to evaluate clinical results after plaster cast fixation for 10 days versus 1 month of moderately displaced and reduced distal radius fractures.

Material and Methods:

In a prospective randomized study, 109 patients with moderately displaced and conservatively treated distal radius fractures (age ≥50 years) were randomized 10 days after reduction to either removal of the plaster cast and immediate mobilization (active group) or to continued plaster cast fixation for another 3 weeks (control group). Grip strength, pincer strength, range of motion, and pain were assessed at 1, 4, and 12 months after reduction. Clinical outcome was evaluated using three functional assessment scores at 12 months.

Results:

Treatment failed in 3/54 (6%) patients in the active group. One of these patients had the plaster cast reinstituted because of feelings of instability. The fractures in the other two patients displaced severely after mobilization and were therefore treated surgically. For the remaining 51 patients in the active group, the range of wrist motion was slightly better at 1 month compared with the controls, but there were no differences in grip or pincer strength or pain at the 1-month follow-up. There were no differences between the active and control group in any outcome at 4 or 12 months, including functional assessment scores at 12 months.

Conclusion:

Treatment with mobilization 10 days after reduction of moderately displaced distal radius fractures resulted in a few treatment failures compared with none among controls. The only functional benefit for the remaining patients was a small and transient increase in range of motion at the 1-month follow-up. Plaster cast removal 10 days after reduction in moderately displaced distal radius fractures is therefore not recommended.

Combined impact of healthy lifestyle factors on lifespan: two prospective cohorts

BACKGROUND

The impact of multiple healthy lifestyle factors on survival time is unclear.

OBJECTIVE

The aim of this study was to examine differences in survival time associated with a healthy lifestyle versus a less healthy lifestyle.

METHODS

This study consisted of 33 454 men (Cohort of Swedish Men) and 30 639 women (Swedish Mammography Cohort) aged 45-83 years and free of cancer and cardiovascular disease at baseline. The healthy lifestyle factors included the following: (i) nonsmoking; (ii) physical activity at least 150 min per week; (iii) alcohol consumption of 0-14 drinks per week; (iv) and healthy diet defined as a modified Dietary Approaches to Stop Hypertension Diet score above the median. Cox proportional hazards regression models and Laplace regression were used to estimate, respectively, hazard ratios of all-cause mortality and differences in survival time.

RESULTS

During follow-up from 1998 through 2014, 8630 deaths amongst men and 6730 deaths amongst women were ascertained through linkage to the Swedish Cause of Death Register. Each of the four healthy lifestyle factors was inversely associated with all-cause mortality and increased survival time. Compared with individuals with no or one healthy lifestyle factor, the multivariable hazard ratios of all-cause mortality for individuals with all four health behaviours were 0.47 (95% 95% confidence interval [CI]: 0.44-0.51) in men and 0.39 (95% CI: 0.35-0.44) in women. This corresponded to a difference in survival time of 4.1 (95% CI: 3.6-4.6) years in men and 4.9 (95% CI: 4.3-5.6) years in women.

CONCLUSION

Adopting healthy lifestyle behaviours may markedly increase lifespan.

Surgical reconstruction of ruptured anterior cruciate ligament prolongs trauma-induced increase of inflammatory cytokines in synovial fluid: an exploratory analysis in the KANON trial

OBJECTIVE

Prospectively monitor how treatment of acutely ruptured anterior cruciate ligament (ACL) affects biomarkers of inflammation and proteolytic degradation over 5 years.

DESIGN

We studied 119 subjects with acute ACL injury from the randomized controlled knee anterior cruciate ligament, non-surgical versus surgical treatment (KANON)-trial (Clinical trial ISRCTN 84752559) who had synovial fluid, serum and urine samples available from at least two out of six visits over 5 years after acute ACL rupture. All subjects followed a similar rehabilitation protocol where, according to randomization, 60 also had early ACL reconstruction and 59 had the option to undergo a delayed ACL reconstruction if needed. Interleukin (IL)-6, IL-8, IL-10, interferon-gamma (IFNγ), tumor necrosis factor (TNF), amino acids alanine, arginine, glycine, serine (ARGS)-aggrecan, C-terminal crosslinking telopeptide type II collagen (CTX-II) and N-terminal crosslinking telopeptide type I collagen (NTX-I) were quantified by enzyme-linked immunosorbent assays (ELISA).

RESULTS

Subjects randomized to early ACL reconstruction had higher cytokine concentrations in index knee synovial fluid at 4 months (IL-6, IL-8, IL-10, TNF), 8 months (IL-6 and TNF) and at 5 years (IFNγ) compared to those randomized to optional delayed reconstruction. Those that underwent delayed ACL reconstruction within 5 years (30 subjects), had higher synovial fluid concentrations of IL-6 at 5 years compared to those treated with rehabilitation alone. No differences between groups were noted for ARGS-aggrecan in synovial fluid and serum or CTX-II and NTX-I in urine over 5 years, neither as randomized nor as treated.

CONCLUSIONS

Surgical ACL reconstruction constitutes a second trauma to the acutely injured joint resulting in a prolonged elevation of already high synovial fluid levels of inflammatory cytokines.

Search for Cosmic-Ray Electron and Positron Anisotropies with Seven Years of Fermi Large Area Telescope Data

The Large Area Telescope on board the Fermi Gamma-ray Space Telescope has collected the largest ever sample of high-energy cosmic-ray electron and positron events since the beginning of its operation. Potential anisotropies in the arrival directions of cosmic-ray electrons or positrons could be a signature of the presence of nearby sources. We use almost seven years of data with energies above 42 GeV processed with the Pass 8 reconstruction. The present data sample can probe dipole anisotropies down to a level of 10^{-3}. We take into account systematic effects that could mimic true anisotropies at this level. We present a detailed study of the event selection optimization of the cosmic-ray electrons and positrons to be used for anisotropy searches. Since no significant anisotropies have been detected on any angular scale, we present upper limits on the dipole anisotropy. The present constraints are among the strongest to date probing the presence of nearby young and middle-aged sources.

Fish consumption and all-cause mortality in a cohort of Swedish men and women

BACKGROUND

Epidemiological studies of fish consumption and all-cause mortality have provided inconsistent results.

OBJECTIVE

We examined the dose-response association between fish consumption and mortality from all causes in a large population-based cohort of Swedish men and women.

METHODS

The study included 72 522 participants (33 973 women and 38 549 men), aged 45-83 years, from the Swedish Mammography Cohort and the Cohort of Swedish Men. Information on fish consumption was obtained through a self-administered questionnaire in 1997. Participants were followed for 17 years (1 January 1998 to 31 December 2014), and data on death and causes of death were ascertained through linkage to the Swedish Cause of Death Register. We used Cox proportional hazard regression to estimate hazard ratios (HRs) of death. Fish consumption was evaluated as a continuous predictor, flexibly modelled with restricted cubic splines to assess potential nonlinear associations.

RESULTS

During follow-up, 16 730 deaths (7168 women and 9562 men) were recorded. The dose-response association between fish consumption and all-cause mortality was U-shaped. Compared with the median fish consumption (women: 25.0; men: 30.5 g day^-1 ), lower levels of consumption were progressively associated with higher mortality risk up to 25% for women [HR 1.25; 95% confidence interval (CI): 1.11, 1.40] and 19% for men (HR 1.19; 95% CI: 1.07, 1.32) with no reported consumption. Increasingly higher levels of fish consumption were associated with higher mortality risk only amongst women, with a 39% higher mortality risk amongst women reporting the highest level of fish consumption (80 g day^-1 ; HR 1.39; 95% CI: 1.15, 1.68).

CONCLUSION

These results indicate a U-shaped association between fish consumption and all-cause mortality, particularly amongst women.

Low-dose developmental exposure to bisphenol A alters the femoral bone geometry in wistar rats

BACKGROUND

Bisphenol A (BPA) is a chemical produced in large volumes for use in manufacturing of consumer products and industrial applications, and an endocrine disruptor known to affect several hormonal systems. Bone produces hormones and is additionally a sensitive hormone target tissue, and is thus potentially sensitive to low doses of endocrine disruptors such as BPA, especially during development.

METHODS

110 pregnant Wistar rats were gavaged with 0; 25 μg; 250 μg; 5000 μg or 50,000 μg BPA/kg bodyweight (bw)/day from gestational day 7 until weaning at postnatal day 22. The three-month-old offspring were sacrificed and right femurs collected for length measurements, geometrical measurements by peripheral quantitative computed tomography (pQCT), as well as for analyses of biomechanical properties using the three-point-bending method.

RESULTS

The femur was elongated in female offspring of dams exposed to 25 or 5000 μg BPA/kg bw/day (1.8% and 2.1%, respectively), and increased cortical thickness (4.7%) was observed in male offspring of dams exposed to 25 μg BPA/kg bw/day, compared to controls (p < 0.005). The biomechanical properties of the bone were not significantly altered.

CONCLUSIONS

In utero and lactational exposure to the lowest BPA dose used in this study altered femoral geometry in both male and female offspring. This was observed at 25 μg BPA/kg bw/day, a dose lower than the Human Equivalent Dose (HED) applied by EFSA to set a temporary TDI (609 μg BPA/kg bw/day), and far lower than the No-Observed-Adverse-Effect-Level (NOAEL) (5000 μg BPA/kg bw/day) on which the US FDA TDI is based.

Stability of Internally Fixed Femoral Neck Fractures Augmented with Resorbable Cement

Background and Aims:

Internal fixation of displaced femoral neck fractures is associated with a high risk for complications such as non-union or avascular necrosis. A stable fracture fixation can improve prognosis although stability is often counteracted by weak osteoporotic bone. The aim with this study was to evaluate whether augmentation with resorbable calcium-phosphate cement could improve fracture stability during the early period after surgery as shown in biomechanical studies.

Material and Methods:

40 ambulatory patients with a displaced femoral neck fracture were randomized to treatment with cannulated screws alone (controls) or screws combined with calcium-phosphate cement for augmentation (augmented). All patients were allowed unrestricted weight bearing after surgery. Fracture movement was measured with radiostereometry (RSA) at 1 and 6 weeks.

Results:

At 1 week the augmented fractures had moved on average 1.9±1.0 mm while movement in the controls was 5.5±3.4 mm (p < 0.0001). The average total movement at weeks was 6.9±2.9 mm and 10.9±5.1 mm, respectively (p < 0.005). Varus angulation and distal migration of the femoral head were the most common movements for both groups although augmented fractures had moved significantly less at both 1 and 6 weeks. There were no significant differences in angulation between groups around the longitudinal and transversal axes or in migration along the transverse or sagittal axes.

Conclusion:

Augmentation with calcium-phosphate cement improved the stability of internally fixed femoral neck fractures during the first six weeks after surgery, with improvement being less pronounced at six weeks compared with at one week.

Unstable Trochanteric Fractures Augmented with Calcium Phosphate Cement

Background and Aims:

Internally fixed unstable trochanteric fractures might be difficult to retain in position during healing. Secondary displacement might lead to malunion and poor functional result. The aim with this study was to measure whether augmentation with resorbable calcium-phosphate cement could improve fracture stability as shown in biomechanical studies.

Material and Methods:

26 ambulatory patients with an unstable trochanteric fracture were randomized to treatment with a sliding screw device alone (Controls) or the same device combined with calcium-phosphate cement for augmentation (Augmented). All patients were allowed unrestricted weight bearing after surgery. Fracture movement was measured with radiostereometry (RSA) at 1 and 6 weeks and at 6 months.

Results:

Two patients died during the study period due to unrelated causes and another three were excluded due to technical problems with the RSA in two and concomitant illness in one. 21 patients (11 Augmented and 10 Controls) were followed according to the study protocol. At 1 week the augmented fractures had moved on average 1.9 ± 1.7 mm while movement in the controls was 4.0 ± 2.4 mm (p < 0.05). The average total movement from the day after surgery until 6 months, when all fractures had healed, was 7.8 ± 6.2 mm for the augmented fractures and 13.2 ± 4.3 mm for the controls (p < 0.05). Varus angulation was the most pronounced rotational movement for both groups although augmented fractures revealed less varus angulation compared with controls at all time points. Rotation around the longitudinal and transversal axes were small with no significant differences between treatment groups.

Conclusion:

Augmentation with calcium-phosphate cement improved the stability of unstable trochanteric fractures fixed with a sliding screw device. The improvement was most pronounced for varus angulation and lateral and distal migration of the head and neck fragment.

Value of air trapping in detection of small airways disease in smokers

Purpose: To test the hypothesis that diffuse and/or focal air trapping are sensitive indicators of airflow obstruction in smoker's small airways disease, when age, gender and presence of emphysematous lesions were allowed for.

Material and Methods: Fifty-eight smokers and 34 never smokers, recruited from a randomized population study of men born in 1933, were investigated by HRCT and by extended pulmonary function tests, including a sensitive test for small airways disease (N2 slope). Diffuse air trapping was evaluated by calculating a quotient of mean lung density at expiration and inspiration. Focal air trapping was scored visually by consensus.

Results: Diffuse air trapping did not differ between non-emphysematous smokers and never smokers. Furthermore, diffuse air trapping correlated well to the quotient between the residual volume and total lung capacity (RV/TLC, p = 0.01) and was consequently higher in emphysematous smokers than in never smokers.

Focal air trapping was found as frequently in smokers without emphysema as in never smokers. Smokers with emphysema showed significantly less focal air trapping. Neither the N2 slope nor any of the other lung function variables differed between those with and without focal air trapping among non-emphysematous smokers.

Conclusion: Neither diffuse nor focal air trapping are sensitive indicators of smoker's small airways disease.

Unrestricted Weight Bearing and Intensive Physiotherapy after Uncemented Total Hip Arthroplasty

Background and Aims:

The effectiveness of partial weightbearing after hip surgery has been questioned as well as the need of intensive physiotherapy.

Material and Methods:

36 patients (average age 54.4, 19 women) operated with uncemented hip arthroplasty were randomized either to unrestricted weightbearing (UWB) combined with intensive physiotherapy or to partial weightbearing (PWB) for 3 months combined with a short self-training program. The load during walking and the muscle strength (MS) in abduction was measured preoperative and subsequent up to 12 months.

Results:

The average peak load on the operated leg at one week was 39.0 kg for the UWB and 25.8 for the PWB group (P = 0.009) while at three months 70.0 and 31.7 (P = 0.001) respectively. At 6 and 12 months there were no differences between the groups. The muscle strength increased in both groups up to six months but there were no differences between the groups.

Conclusions:

Even though patients applied more load than the recommended 15 kg most patients were able to comply with partial weightbearing fairly well. The effect of intensive physiotherapy on the muscle strength after hip arthroplasty is questionable.

RSA Applications in Monitoring of Fracture Healing in Clinical Trials

Radiostereometric analysis (RSA) was originally developed as a method for performing highly accurate three-dimensional measurements in vivo over time from sequential radiographs. Since its introduction over twenty years ago, the RSA method has proven itself as a powerful tool with numerous orthopaedic applications. RSA has been used extensively in studies of prosthetic fixation and has been shown to be the method of choice for these studies. RSA has, however, also been successfully applied to a limited number of studies examining fracture healing, namely in fractures of the radius, ankle, tibial plateau, trochanter and femoral neck, as well as studies of bone healing following spinal fusion and tibial osteotomies. RSA follow-up of a fracture will provide definitive demonstration of the exact time of union, i.e. the achievement of fracture stability. This information can be invaluable in randomized clinical trials of fracture treatment. Phantom model studies have proven useful for effective preoperative planning and interpretation of RSA results. The RSA method is a highly accurate, precise and safe objective method for studying fracture healing in clinical trials. The RSA method may serve as a scientific tool to accurately evaluate the significance of supporting novel biomaterials for the early stability and the rate of healing in fractures.

A surprisingly poor correlation between in vitro and in vivo testing of biomaterials for bone regeneration: results of a multicentre analysis

New regenerative materials and approaches need to be assessed through reliable and comparable methods for rapid translation to the clinic. There is a considerable need for proven in vitro assays that are able to reduce the burden on animal testing, by allowing assessment of biomaterial utility predictive of the results currently obtained through in vivo studies. The purpose of this multicentre review was to investigate the correlation between existing in vitro results with in vivo outcomes observed for a range of biomaterials. Members from the European consortium BioDesign, comprising 8 universities in a European multicentre study, provided data from 36 in vivo studies and 47 in vitro assays testing 93 different biomaterials. The outcomes of the in vitro and in vivo experiments were scored according to commonly recognised measures of success relevant to each experiment. The correlation of in vitro with in vivo scores for each assay alone and in combination was assessed. A surprisingly poor correlation between in vitro and in vivo assessments of biomaterials was revealed indicating a clear need for further development of relevant in vitro assays. There was no significant overall correlation between in vitro and in vivo outcome. The mean in vitro scores revealed a trend of covariance to in vivo score with 58 %. The inadequacies of the current in vitro assessments highlighted here further stress the need for the development of novel approaches to in vitro biomaterial testing and validated pre-clinical pipelines.

Search for Spectral Irregularities due to Photon-Axionlike-Particle Oscillations with the Fermi Large Area Telescope

We report on the search for spectral irregularities induced by oscillations between photons and axionlike-particles (ALPs) in the γ-ray spectrum of NGC 1275, the central galaxy of the Perseus cluster. Using 6 years of Fermi Large Area Telescope data, we find no evidence for ALPs and exclude couplings above 5×10^{-12}  GeV^{-1} for ALP masses 0.5≲m_{a}≲5  neV at 95% confidence. The limits are competitive with the sensitivity of planned laboratory experiments, and, together with other bounds, strongly constrain the possibility that ALPs can reduce the γ-ray opacity of the Universe.

Resolving the Extragalactic γ-Ray Background above 50 GeV with the Fermi Large Area Telescope

The Fermi Large Area Telescope (LAT) Collaboration has recently released a catalog of 360 sources detected above 50 GeV (2FHL). This catalog was obtained using 80 months of data re-processed with Pass 8, the newest event-level analysis, which significantly improves the acceptance and angular resolution of the instrument. Most of the 2FHL sources at high Galactic latitude are blazars. Using detailed Monte Carlo simulations, we measure, for the first time, the source count distribution, dN/dS, of extragalactic γ-ray sources at E>50  GeV and find that it is compatible with a Euclidean distribution down to the lowest measured source flux in the 2FHL (∼8×10^{-12}  ph cm^{-2} s^{-1}). We employ a one-point photon fluctuation analysis to constrain the behavior of dN/dS below the source detection threshold. Overall, the source count distribution is constrained over three decades in flux and found compatible with a broken power law with a break flux, S_{b}, in the range [8×10^{-12},1.5×10^{-11}]  ph cm^{-2} s^{-1} and power-law indices below and above the break of α_{2}∈[1.60,1.75] and α_{1}=2.49±0.12, respectively. Integration of dN/dS shows that point sources account for at least 86_{-14}^{+16}% of the total extragalactic γ-ray background. The simple form of the derived source count distribution is consistent with a single population (i.e., blazars) dominating the source counts to the minimum flux explored by this analysis. We estimate the density of sources detectable in blind surveys that will be performed in the coming years by the Cherenkov Telescope Array.

Measurement of the high-energy gamma-ray emission from the Moon with the Fermi Large Area Telescope

We have measured the gamma-ray emission spectrum of the Moon using the data collected by the Large Area Telescope onboard the Fermi satellite during its first seven years of operation, in the energy range from 30 MeV up to a few GeV. We have also studied the time evolution of the flux, finding a correlation with the solar activity. We have developed a full Monte Carlo simulation describing the interactions of cosmic rays with the lunar surface. The results of the present analysis can be explained in the framework of this model, where the production of gamma rays is due to the interactions of cosmic-ray proton and helium nuclei with the surface of the Moon. Finally, we have used our simulation to derive the cosmic-ray proton and helium spectra near Earth from the Moon gamma-ray data.

Searching for Dark Matter Annihilation from Milky Way Dwarf Spheroidal Galaxies with Six Years of Fermi Large Area Telescope Data

The dwarf spheroidal satellite galaxies (dSphs) of the Milky Way are some of the most dark matter (DM) dominated objects known. We report on γ-ray observations of Milky Way dSphs based on six years of Fermi Large Area Telescope data processed with the new Pass8 event-level analysis. None of the dSphs are significantly detected in γ rays, and we present upper limits on the DM annihilation cross section from a combined analysis of 15 dSphs. These constraints are among the strongest and most robust to date and lie below the canonical thermal relic cross section for DM of mass ≲100  GeV annihilating via quark and τ-lepton channels.

Interleukin-6 and tumor necrosis factor alpha in synovial fluid are associated with progression of radiographic knee osteoarthritis in subjects with previous meniscectomy

OBJECTIVE

To explore potential associations between proinflammatory cytokines in synovial fluid and progression of osteoarthritis (OA) in meniscectomized subjects.

DESIGN

We studied 132 subjects on average 18 years after meniscectomy, with a second examination 4-10 years later. We measured concentrations of interleukin (IL)-6, -8 and tumor necrosis factor (TNF)-α by multiplex immunoassay, graded radiographic features of tibiofemoral and patellofemoral OA according to the Osteoarthritis Research Society International (OARSI) atlas, scored patient-reported outcomes using the Knee Injury and Osteoarthritis Outcome Score (KOOS), and used logistic regression (adjusted for age, gender, body mass index, and time between examinations) for assessment of associations.

RESULTS

Higher first examination concentrations of IL-6 and TNF-α were associated with increased risk for subsequent osteophyte progression (odds ratios (OR); 95% confidence intervals 1.05; 1.00-1.09 and 1.35; 1.03-1.75). Higher second examination concentrations of TNF-α were associated with having progressed in loss of joint space (OR 1.70; 1.15-2.52) or having worsened in the activity of daily living subscale of KOOS (OR 1.50; 1.07-2.09) in the preceding years. Subjects with increasing concentrations of IL-6 or TNF-α between examinations were five times more likely to have progressed in joint space narrowing between the same examinations, as compared to those with stable or decreasing concentrations (OR 5.17; 1.54-17.32 and 5.01; 1.32-18.92).

CONCLUSIONS

In subjects with previous meniscectomy, higher or over time increasing synovial fluid levels of IL-6 and TNF-α seems to be associated with increased risk for progression of radiographic OA.

Type II collagen C2C epitope in human synovial fluid and serum after knee injury--associations with molecular and structural markers of injury

PURPOSE

Investigate in a cross-sectional study time-dependent changes of synovial fluid type II collagen epitope C2C concentrations after knee injury and correlate to other joint injury biomarkers.

METHODS

Synovial fluid samples were aspirated between 0 days and 7 years after injury (n = 235). Serum was collected from 71 of the knee injured patients. Synovial fluid from 8 knee-healthy subjects was used as reference. C2C was quantified by immunoassay and structural injury was determined from magnetic resonance images (MRI) of the injured knee acquired 1-38 days after injury (n = 98). Additional joint injury biomarker results were from earlier investigations of the same samples.

RESULTS

Synovial fluid C2C concentrations were higher in injured knees than in knees of reference subjects from 1 day up to 7 years after injury. C2C concentrations in synovial fluid and serum were correlated (r = 0.403, P < 0.001). In synovial fluid from subjects early after injury (0-33 days), C2C concentrations were correlated with cross-linked C-telopeptide of type II collagen (r = 0.444, P = 0.003), ARGS-aggrecan (r = 0.337, P < 0.001), osteocalcin (r = 0.345, P < 0.001), osteopontin (r = 0.371, P < 0.001) and IL-8 (r = -0.385, P < 0.001), but not with structural joint injury as visualized on MRI.

CONCLUSION

The increased levels of synovial fluid C2C after injury, together with the associations seen with several other injury-related biomarkers, suggest that an acute knee injury is associated with an immediate and sustained local degradation of type II collagen.

Childhood trauma mediates the association between ethnic minority status and more severe hallucinations in psychotic disorder

BACKGROUND

Ethnic minority status and childhood trauma are established risk factors for psychotic disorders. Both are found to be associated with increased level of positive symptoms, in particular auditory hallucinations. Our main aim was to investigate the experience and effect of childhood trauma in patients with psychosis from ethnic minorities, hypothesizing that they would report more childhood trauma than the majority and that this would be associated with more current and lifetime hallucinations.

METHOD

In this cross-sectional study we included 454 patients with a SCID-I DSM-IV diagnosis of non-affective or affective psychotic disorder. Current hallucinations were measured with the Positive and Negative Syndrome Scale (P3; Hallucinatory Behaviour). Lifetime hallucinations were assessed with the SCID-I items: auditory hallucinations, voices commenting and two or more voices conversing. Childhood trauma was assessed with the Childhood Trauma Questionnaire, self-report version.

RESULTS

Patients from ethnic minority groups (n = 69) reported significantly more childhood trauma, specifically physical abuse/neglect, and sexual abuse. They had significantly more current hallucinatory behaviour and lifetime symptoms of hearing two or more voices conversing. Regression analyses revealed that the presence of childhood trauma mediated the association between ethnic minorities and hallucinations.

CONCLUSIONS

More childhood trauma in ethnic minorities with psychosis may partially explain findings of more positive symptoms, especially hallucinations, in this group. The association between childhood trauma and these first-rank symptoms may in part explain this group's higher risk of being diagnosed with a schizophrenia-spectrum diagnosis. The findings show the importance of childhood trauma in symptom development in psychosis.

Dietary exposure to polychlorinated biphenyls is associated with increased risk of stroke in women

OBJECTIVE

The potentially beneficial effects of fish consumption on stroke may be modified by major food contaminants in fish. Polychlorinated biphenyls (PCBs) in particular are proposed to play a role in the aetiology of stroke. The aim of this study was to assess the association between dietary PCB exposure and stroke risk with the intake of long-chain omega-3 fish fatty acids and fish consumption.

DESIGN

The prospective population-based Swedish Mammography Cohort was examined. It was comprised of 34,591 women free of cardiovascular diseases and cancer at baseline in 1997 and followed up for 12 years. Validated estimates of dietary PCB exposure were obtained via a food frequency questionnaire at baseline. Incident cases of stroke were ascertained through register linkage.

RESULTS

During 12 years of follow-up (397,309 person-years), there were 2015 incident cases of total stroke (1532 ischaemic strokes, 216 intracerebral haemorrhages, 94 subarachnoid haemorrhages and 173 unspecified strokes). Multivariable-adjusted relative risks (RR), controlled for known stroke risk factors and fish consumption, were 1.67 [95% confidence interval (CI), 1.29-2.17] for total stroke, 1.61 (95% CI, 1.19-2.17) for ischaemic stroke and 2.80 (95% CI, 1.42-5.55) for haemorrhagic stroke for women in the highest quartile of dietary PCB exposure (median 288 ng day(-1) ) compared with women in the lowest quartile (median 101 ng day(-1) ).

CONCLUSION

Dietary exposure to PCBs was associated with an increased stroke risk in women, especially haemorrhagic stroke. The results provide important information regarding the risk-benefit analysis of fish consumption, particularly for cerebrovascular disease prevention.

Sex differences in the association between smoking and abdominal aortic aneurysm

Background

It is unclear whether recommendations about ultrasound screening programmes for abdominal aortic aneurysm (AAA) among men should be extended to include women who smoke. The aim was to examine sex-specific dose–response associations between AAA risk and smoking status, pack-years smoked and time since smoking cessation.

Methods

Women in the Swedish Mammography Cohort and men in the Cohort of Swedish Men were followed up from 1998 to 2011. AAA was identified through linkage of the cohorts to the Swedish Inpatient Register and the Swedish National Register for Vascular Surgery (Swedvasc), and not through general ultrasound screening. Associations were estimated with Cox proportional hazards models.

Results

The cohorts included 35 550 women and 42 596 men, aged 46–84 years. During follow-up, AAA was identified in 199 women and 958 men. The incidence of AAA per 100 000 person-years was 76 among men who never smoked and 136 among women who currently smoke. Regarding AAA risk, women were more sensitive to current smoking (Pinteraction= 0·002). Compared with never smokers, the hazard ratio (HR) for AAA in current smokers with more than 20 pack-years was 10·97 (95 per cent confidence interval 7·41 to 16·26) among women and 6·55 (5·36 to 7·99) among men. Following smoking cessation, women had a more rapid decline in excess risk (Pinteraction &lt; 0·001). The risk was halved after 11 years (HR 0·51, 0·32 to 0·81) among women and after 23 years (HR 0·50, 0·42 to 0·60) among men.

Conclusion

There were sex differences in the associations between smoking status and AAA risk. These data support further investigation of targeted AAA screening among women who smoke.