Global assessment of C-reactive protein and health-related outcomes: an umbrella review of evidence from observational studies and Mendelian randomization studies

Unraveling the role of BMI and blood markers in the relationship between plant-based diets and osteoporosis: A prospective cohort study

BACKGROUND

The potential adverse effects of plant-based diets on bone health have raised significant concern, while the prospective evidence is limited. This study aimed to evaluate the association between plant-based diet indexes and incident osteoporosis while exploring the underlying mechanisms involved in this relationship.

METHODS

The analysis included 202,063 UK Biobank participants conducted between 2006 and 2022. Plant-based diet indexes (hPDI and uPDI) were calculated using the 24-h dietary questionnaire. Cox proportional risk regression and mediation analysis were used to explore the associations of plant-based diet indexes with osteoporosis, estimating the contribution of BMI and blood markers.

RESULTS

We found the highest quintile for hPDI (HR = 1.16; 95% CI: 1.05 to 1.28) and uPDI (HR = 1.15; 95% CI: 1.05 to 1.26) were associated with an increased risk of osteoporosis. BMI was identified as an important mediator in the association between hPDI and osteoporosis, with mediation proportions of 46.17%. For blood markers, the mediating (suppressing) effects of C-reactive protein, alkaline phosphatase, and insulin-like growth factor-1 on the association between uPDI (hPDI) and osteoporosis were significant, ranging from 5.63%-16.87% (4.57%-6.22%).

CONCLUSION

Adherence to a plant-based diet is associated with a higher risk of osteoporosis, with BMI and blood markers potentially contributing to this relationship. Notably, even a healthy plant-based diet necessitates attention to weight management to mitigate its impact on bone loss. These findings emphasize the importance of personalized dietary recommendations and lifestyle interventions to decrease the risk of osteoporosis.

Association of serum calcium, vitamin D, and C-reactive protein with all-cause and cause-specific mortality in an osteoarthritis population in the UK: a prospective cohort study

BACKGROUND

Osteoarthritis is a prevalent musculoskeletal condition, but the role of specific serum biomarkers, such as calcium, vitamin D, and C-reactive protein (CRP), in predicting mortality among individuals with osteoarthritis remains unclear.

METHODS

This observational study analyzed longitudinal data from over 500,000 participants in the UK Biobank, identifying those with osteoarthritis using ICD-9/10 codes or self-reported history. We performed multivariable cox-regression and flexible parametric survival model (FPSM) for survival analysis, with adjustments made through the inverse probability of treatment weight (IPTW) for baseline covariates identified by directed acyclic graphs (DAGs).

RESULTS

Of the 49,082 osteoarthritis population, the average age was 60.69 years, with 58.7% being female. During the follow-up period exceeding 15 years, a total of 5,522 people with osteoarthritis died. High serum calcium levels, compared to normal serum calcium levels, were significantly associated with all-cause mortality (hazard ratio (HR) 1.33, 95% confidence interval (CI) 1.11, 1.59), cardiovascular diseases (CVD)-related deaths (HR 1.55, 95% CI 1.05, 2.29), and other deaths (HR 1.59, 95% CI 1.20, 2.11). Low serum calcium levels, compared to normal serum calcium levels, was linked with CVD-related deaths (HR 2.06, 95% CI 1.02, 4.14). Vitamin D insufficiency, compared to sufficient vitamin D levels, was correlated with all-cause mortality (HR 1.22, 95% CI 1.13, 1.33), CVD-related deaths (HR 1.43, 95% CI 1.20, 1.72), and other deaths (HR 1.26, 95% CI 1.09, 1.45) but not with cancer-related deaths. High serum CRP levels, compared to normal CRP levels, were associated with all outcomes (all-cause mortality: HR 1.22, 95% CI 1.12, 1.33; CVD-related death: HR 1.24, 95%CI 1.03, 1.49; cancer-related death: HR 1.23, 95% CI 1.09, 1.40; other deaths: HR 1.19, 95%CI 1.03, 1.38).

CONCLUSIONS

Both high and low serum calcium levels, elevated CRP, and vitamin D insufficiency are potential predictors of increased mortality risk in the osteoarthritis population. These findings emphasize the importance of monitoring and possibly addressing these serum biomarkers in osteoarthritis populations to improve long-term outcomes. Further studies are needed to understand the underlying mechanisms and to propose therapeutic interventions.

The Role of Melatonin in the Inflammatory Process in Patients with Hyperglycemia and Leishmania Infection

Type 2 diabetes mellitus is a metabolic disorder that causes chronic high blood sugar levels, and diabetic patients are more susceptible to infections. American cutaneous leishmaniasis is an infectious disease caused by a parasite that affects the skin and mucous membranes, leading to one or multiple ulcerative lesions. Chronic inflammation and functional changes in various organs and systems, including the immune system, are the primary causes of both diseases. Melatonin, an essential immunomodulatory, antioxidant, and neuroprotective agent, can benefit many immunological processes and infectious diseases, including leishmaniasis. Although, limited reports are available on diabetic patients with leishmaniasis. The literature suggests that melatonin may play a promising role in inflammatory disorders. This study was designed to assess melatonin levels and inflammatory mediators in diabetic patients affected by leishmaniasis. Blood samples from 25 individuals were analyzed and divided into four groups: a control group (without any diseases), a Leishmania-positive group, patients with type 2 diabetes mellitus, and patients with a combination of both diseases. This study measured the serum levels of melatonin through ELISA, while IL-4 and TNF-α were measured using flow cytometry, and C-reactive protein was measured through turbidimetry. This study found that patients with leishmaniasis significantly increased TNF-α and decreased melatonin levels. However, the group of diabetic patients with leishmaniasis showed higher melatonin levels than the control group. These observations suggest that TNF-α may influence melatonin production in patients with American cutaneous leishmaniasis, potentially contributing to the inflammatory characteristics of both diseases.

No evidence for causal effects of C-reactive protein (CRP) on chronic pain conditions: a Mendelian randomization study

Objective

We conducted a Mendelian randomization (MR) study to examine causal associations of C-reactive protein (CRP) with (1) spinal pain; (2) extent of multisite chronic pain; and (3) chronic widespread musculoskeletal pain.

Design

Two-sample MR study.

Setting/Subjects

We used summary statistics from publicly available genome-wide association studies (GWAS) conducted in multiple cohorts and biobanks. Genetic instrumental variables were taken from an exposure GWAS of CRP (n=204,402). Outcome GWASs examined spinal pain (n=1,028,947), extent of multisite chronic pain defined as the number of locations with chronic pain (n=387,649), and chronic widespread pain (n=249,843).

Methods

We examined MR evidence for causal associations using inverse-variance weighted (IVW) analysis and sensitivity analyses using other methods. We calculated odds ratios (ORs), 95% confidence intervals (95% CIs), and p-values, using a Bonferroni correction (p<0.0166) to account for 3 primary comparisons.

Results

Greater serum CRP (mg/L) was not significantly causally associated with spinal pain (OR=1.04, 95% CI 1.00-1.08; p=0.07) in IVW analysis. Greater serum CRP also showed no significant causal association with extent of multisite chronic pain in IVW analysis (beta coefficient= 0.014, standard error=0.011; p=0.19). CRP also showed no significant causal association with chronic widespread pain in IVW analysis (OR=1.00, 95% CI 1.00-1.00; p=0.75). All secondary and sensitivity analyses also showed no significant associations.

Conclusions

This MR study found no causal association of CRP on spinal pain, the extent of chronic pain, or chronic widespread pain. Future studies examining mechanistic biomarkers for pain conditions should consider other candidates besides CRP.

Genetic evidence for the causal effects of C-reactive protein on self-reported habitual sleep duration

Inflammatory responses to acute stimuli are proposed to regulate sleep, but the relationship between chronic inflammation and habitual sleep duration is elusive. Here, we study this relation using genetically predicted level of chronic inflammation, indexed by CRP and IL6 signaling, and self-reported sleep duration. By Mendelian randomization analysis, we show that elevated CRP level within <10 mg/L has a homeostatic effect that facilitates maintaining 7-8 h sleep duration per day - making short-sleepers sleep longer (p = 2.42 × 10-2) and long-sleepers sleep shorter (1.87 × 10-7); but it is not associated with the overall sleep duration (p = 0.17). This homeostatic effect replicated in an independent CRP dataset. We observed causal effects of the soluble interleukin 6 receptor and gp130 on overall sleep duration (p = 1.62 × 10-8, p = 2.61 × 10-58, respectively), but these effects disappeared when CRP effects were accounted for in the model. Using polygenic score analysis, we found that the homeostatic effect of CRP on sleep duration stems primarily from the genetic variants within the CRP gene region: when genetic variants outside of this region were used to predict CRP levels, the opposite direction of effect was observed. In conclusion, we show that elevated CRP level may causally facilitate maintaining an optimal sleep duration that is beneficial to health, thus updating our current knowledge of immune regulation on sleep.

Temporal and spatial effects on C-reactive protein's regulation of inducible nitric oxide synthase production in periodontal disease

BACKGROUND

Inducible nitric oxide synthase (iNOS) is associated with inflammation and osteoclastic differentiation in periodontal disease. This study was conducted to compare the time-dependent variation in iNOS production between the gingiva and other periodontal tissues and to explore the potential association with C-reactive protein (CRP) in early periodontal disease.

METHODS

Ligature-induced periodontal disease models (0-14 days) were established in wild-type and CRP knockout rats. Changes in CRP, iNOS, and autophagy levels were examined in the gingiva and other periodontal tissues. Macrophages were treated with lipopolysaccharide and chloroquine to explore the role of autophagy in iNOS production. iNOS, CRP, and autophagy-related proteins were analyzed using Western blotting, immunostaining, and enzyme-linked immunosorbent assays. mRNA expression was detected by quantitative real-time polymerase chain reaction. Hematoxylin and eosin staining was used for histological analysis. Cathepsin K immunostaining and microcomputed tomography of the maxillae were performed to compare alveolar bone resorption.

RESULTS

iNOS and CRP levels increased rapidly in periodontal tissues, as observed on Day 2 of ligature, then decreased more rapidly in the gingiva than in other periodontal tissues. CRP deficiency did not prevent iNOS generation, but effectively accelerated iNOS reduction and delayed alveolar bone loss. The CRP effect on iNOS was accompanied by a change in autophagy, which was reduced by CRP knockout.

CONCLUSIONS

The regulation of iNOS by CRP shows temporospatial variation in early periodontal disease and is potentially associated with autophagy. These findings may contribute to the early detection and targeted treatment of periodontal disease.

Risk factors for myopia among children and adolescents: an umbrella review of published meta-analyses and systematic reviews

AIMS

To identify potential risk factors for myopia in children and adolescents and assess the credibility of each evidence, providing reference for the development of myopia prevention strategies.

METHODS

We searched PubMed, Web of Science and Embase databases from inception to April 2022 to find systematic reviews or meta-analyses investigating the relationship between potential risk factors and myopia, and conducted an umbrella review. We recalculated the pooled effect sizes and 95% CIs of each potential risk factor through random-effects model, and reported its 95% prediction interval and between-study heterogeneity. Small-study effect and excess of significance bias were assessed to reveal potential publication bias.

RESULTS

Twelve publications were included in this umbrella review, including eight meta-analyses and four qualitative systematic reviews. Twenty-two factors were identified, of which 16 were analysed quantitatively. Ten factors showed statistically significant association with myopia. Myopia in one or two parents and per additional hour of time spend outdoors per week were rated as highly suggestive evidence. Near work and gender were evaluated as suggestive evidence. The other five factors are weak evidence.

CONCLUSIONS

We found several risk factors for myopia with different levels of evidence, of which parental myopia presented the strongest association with myopia in children and adolescents. Our findings contribute to a better understanding of the association between potential risk factors and myopia among children and adolescents and are important for informing parenting, education, clinical practice guidelines and public health policy.

PROSPERO TRIAL REGISTRATION NUMBER

CRD42022333053.

Influence of Air Pollution Exposures on Cardiometabolic Risk Factors: a Review

PURPOSE OF REVIEW

The increasing prevalence of cardiometabolic risk factors (CRFs) contributes to the rise in cardiovascular disease. Previous research has established a connection between air pollution and both the development and severity of CRFs. Given the ongoing impact of air pollution on human health, this review aims to summarize the latest research findings and provide an overview of the relationship between different types of air pollutants and CRFs.

RECENT FINDINGS

CRFs include health conditions like diabetes, obesity, hypertension etc. Air pollution poses significant health risks and encompasses a wide range of pollutant types, air pollutants, such as particulate matter (PM), nitrogen dioxide (NO2), sulfur dioxide (SO2), and ozone (O2). More and more population epidemiological studies have shown a positive correlation between air pollution and CRFs. Although various pollutants have diverse effects on specific cellular molecular pathways, their main influence is on oxidative stress, inflammation response, and impairment of endothelial function. More and more studies have proved that air pollution can promote the occurrence and development of cardiovascular and metabolic risk factors, and the research on the relationship between air pollution and CRFs has grown intensively. An increasing number of studies are using new biological monitoring indicators to assess the occurrence and development of CRFs resulting from exposure to air pollution. Abnormalities in some important biomarkers in the population (such as homocysteine, uric acid, and C-reactive protein) caused by air pollution deserve more attention. Further research is warranted to more fully understand the link between air pollution and novel CRF biomarkers and to investigate potential prevention and interventions that leverage the mechanistic link between air pollution and CRFs.

Effect of Nutrition Education on Health Science University Students to Improve Cardiometabolic Profile and Inflammatory Status

The inadequate lifestyle associated with university life may have a negative impact on various cardiometabolic factors. The aim of this study was to evaluate the effect of a one-year nutrition education course on cardiometabolic parameters in undergraduate health science students. During the 2021-22 academic year, 1.30 h nutrition sessions were conducted twice a week. Capillary blood samples were collected and centrifuged to measure cardiometabolic and inflammatory biomarkers in serum. The sample studied consisted of 49 students: 20.4% male and 79.6% female. The nutritional intervention resulted in changes in dietary patterns, with increased consumption of vegetables, nuts and legumes. After the course, females showed an increase in HDL-cholesterol levels (p = 0.007) and no change in LDL-cholesterol levels (p = 0.189). On the other hand, males showed significant changes in HDL-cholesterol (p = 0.001) and LDL-cholesterol (p = 0.043) levels. The atherogenic index was also significantly reduced (p < 0.001) in both males (p = 0.009) and females (p = 0.002). Differences were also observed in the increase in vitamin D levels in both males and females, although the magnitude of the increase was greater in the men (Δ = 7.94, p = 0.016 in men vs. Δ = 4.96, p = 0.001 in women). The monocyte-to-HDL ratio (MHR) showed a significant reduction, although these differences were only significant in males. Students with low vitamin D levels had higher LDL-cholesterol values (p = 0.01) and atherogenic index (p = 0.029). Adjusted linear regression analysis showed a significant association between post-course vitamin D MHR (β = -0.42, IC: -0.29, -0.06, p < 0.01). These findings suggest the importance of including nutrition education programs during the university stage for the prevention of long-term health problems.

How to Manage Metallosis: A Retrospective Cohort Analysis after Revision Hip Surgery

BACKGROUND

Adverse local tissue reactions to metal debris are due to a metal-on-metal bearing complication caused by micromotions at modular interfaces that induce corrosion of the protective oxide layer. This process could lead to wear, fretting, and abrasion with the release of metal ions locally and systemically, which may cause adverse local reactions in nearby tissues. The aim of this study is to describe a series of patients with painful local adverse tissue reactions secondary to corrosion at the modular neck-body interface, to document the clinical presentation, diagnostic workup, and surgical findings of our research, and to search for a possible correlation between metallosis and infection.

METHODS

A retrospective study of patients with adverse local tissue reactions due to metal surface corrosion was performed. Blood samples were collected to identify erythrocyte sedimentation rate, C reactive protein, and procalcitonin, and a magnetic resonance imaging protocol was performed.

RESULTS

Serum cobalt and chromium levels of the 43 patients tested were significantly higher on average. However, both erythrocyte sedimentation rate and C-reactive protein were significantly elevated. Magnetic resonance imaging showed adverse reactions to metal debris with large soft tissue masses and surrounding tissue damage.

CONCLUSIONS

Corrosion in hip prosthesis can lead to the release of metal ions and debris locally and systemically, resulting in local soft tissue changes. A "tumor-like" debridement can reduce this complication.

Characteristics of preoperative atrial fibrillation in geriatric patients with hip fracture and construction of a clinical prediction model: a retrospective cohort study

INTRODUCTION

Atrial fibrillation is the most common atrial arrhythmia in the perioperative period and is associated with prolonged hospital stay, increased costs, and increased mortality. However, there are few data on the predictors and incidence of preoperative atrial fibrillation in hip fracture patients. Our aim was to identify predictors of preoperative atrial fibrillation and to propose a valid clinical prediction model.

METHODS

Predictor variables included demographic and clinical variables. LASSO regression analyzes were performed to identify predictors of preoperative atrial fibrillation, and models were constructed and presented as nomograms. Area under the curve, calibration curve, and decision curve analysis (DCA) were used to examine the discriminative power, calibration, and clinical efficacy of the predictive models. Bootstrapping was used for validation.

RESULTS

A total of 1415 elderly patients with hip fractures were analyzed. Overall, 7.1% of patients had preoperative atrial fibrillation, and they were at significant risk for thromboembolic events. Patients with preoperative AF had a significantly longer delay in surgery than those without preoperative atrial fibrillation (p < 0.05). Predictors for preoperative atrial fibrillation were hypertension (OR 1.784, 95% CI 1.136-2.802, p < 0.05), C-reactive protein at admission (OR 1.329, 95% CI 1.048-1.662, p < 0.05), systemic inflammatory response index at admission (OR 2.137, 95% CI, 1.678-2.721 p < 0.05), Age-Adjusted Charlson Comorbidity Index (OR 1.542, 95% CI 1.326-1.794, p < 0.05), low potassium(OR 2.538, 95% CI 1.623-3.968, p < 0.05), anemia(OR 1.542, 95% CI 1.326-1.794, p < 0.05). Good discrimination and calibration effect of the model was showed. Interval validation could still achieve the C-index value of 0.799. DCA demonstrated this nomogram has good clinical utility.

CONCLUSION

This model has a good predictive effect on preoperative atrial fibrillation in elderly patients with hip fractures, which can help to better plan clinical evaluation.

Socio-Demographic, Lifestyle, and Cardiometabolic Characteristics Associated with Low-Grade Systemic Inflammation in Russian Adult Population

Mortality from cardiovascular diseases (CVDs) is higher in Russia compared to other European countries. High-sensitivity C-reactive protein (hs-CRP) is a biomarker of inflammation, and its elevated levels indicate increased CVD risks. We aim to describe the prevalence of low-grade systemic inflammation (LGSI) and the associated factors in a Russian population. The Know Your Heart cross-sectional study was conducted in Arkhangelsk, Russia in 2015-2017 with a population sample aged 35-69 years (n = 2380). LGSI was defined as hs-CRP ≥ 2 and <10 mg/L, and its associations with socio-demographic, lifestyle, and cardiometabolic characteristics were analyzed. The prevalence of LGSI (age-standardized to European Standard Population 2013) was 34.1% (33.5% in men and 36.1% in women). In the total sample, the increased odds ratios (ORs) of LGSI were associated with abdominal obesity (2.1), smoking (1.9), dyslipidemia (1.5), pulmonary diseases (1.4), and hypertension (1.3); the decreased ORs were in women (0.6) and in married participants (0.6). In men, the ORs were higher with abdominal obesity (2.1), smoking (2.0), CVDs (1.5), and hazardous drinking (1.5); in women-with abdominal obesity (4.4) and pulmonary diseases (1.5). In conclusion, one-third of the adult population in Arkhangelsk had LGSI. Abdominal obesity was the strongest LGSI correlate in both sexes, while the profiles of other associated factors were different between men and women.

Systemic inflammation as a biomarker of seizure propensity and a target for treatment to reduce seizure propensity

People with diabetes can wear a device that measures blood glucose and delivers just the amount of insulin needed to return the glucose level to within bounds. Currently, people with epilepsy do not have access to an equivalent wearable device that measures a systemic indicator of an impending seizure and delivers a rapidly acting medication or other intervention (e.g., an electrical stimulus) to terminate or prevent a seizure. Given that seizure susceptibility is reliably increased in systemic inflammatory states, we propose a novel closed-loop device where release of a fast-acting therapy is governed by sensors that quantify the magnitude of systemic inflammation. Here, we review the evidence that patients with epilepsy have raised levels of systemic indicators of inflammation than controls, and that some anti-inflammatory drugs have reduced seizure occurrence in animals and humans. We then consider the options of what might be incorporated into a responsive anti-seizure system.

Tools for assessing quality and risk of bias in Mendelian randomization studies: a systematic review

BACKGROUND

The use of Mendelian randomization (MR) in epidemiology has increased considerably in recent years, with a subsequent increase in systematic reviews of MR studies. We conducted a systematic review of tools designed for assessing risk of bias and/or quality of evidence in MR studies and a review of systematic reviews of MR studies.

METHODS

We systematically searched MEDLINE, Embase, the Web of Science, preprints servers and Google Scholar for articles containing tools for assessing, conducting and/or reporting MR studies. We also searched for systematic reviews and protocols of systematic reviews of MR studies. From eligible articles we collected data on tool characteristics and content, as well as details of narrative description of bias assessment.

RESULTS

Our searches retrieved 2464 records to screen, from which 14 tools, 35 systematic reviews and 38 protocols were included in our review. Seven tools were designed for assessing risk of bias/quality of evidence in MR studies and evaluation of their content revealed that all seven tools addressed the three core assumptions of instrumental variable analysis, violation of which can potentially introduce bias in MR analysis estimates.

CONCLUSION

We present an overview of tools and methods to assess risk of bias/quality of evidence in MR analysis. Issues commonly addressed relate to the three standard assumptions of instrumental variables analyses, the choice of genetic instrument(s) and features of the population(s) from which the data are collected (particularly in two-sample MR), in addition to more traditional non-MR-specific epidemiological biases. The identified tools should be tested and validated for general use before recommendations can be made on their widespread use. Our findings should raise awareness about the importance of bias related to MR analysis and provide information that is useful for assessment of MR studies in the context of systematic reviews.

Pleiotropic genetic architecture and novel loci for C-reactive protein levels

C-reactive protein is involved in a plethora of pathophysiological conditions. Many genetic loci associated with C-reactive protein are annotated to lipid and glucose metabolism genes supporting common biological pathways between inflammation and metabolic traits. To identify novel pleiotropic loci, we perform multi-trait analysis of genome-wide association studies on C-reactive protein levels along with cardiometabolic traits, followed by a series of in silico analyses including colocalization, phenome-wide association studies and Mendelian randomization. We find 41 novel loci and 19 gene sets associated with C-reactive protein with various pleiotropic effects. Additionally, 41 variants colocalize between C-reactive protein and cardiometabolic risk factors and 12 of them display unexpected discordant effects between the shared traits which are translated into discordant associations with clinical outcomes in subsequent phenome-wide association studies. Our findings provide insights into shared mechanisms underlying inflammation and lipid metabolism, representing potential preventive and therapeutic targets.

Inflammation biomarkers and incident coronary heart disease: the Reasons for Geographic And Racial Differences in Stroke Study

BACKGROUND

Individual inflammation biomarkers are associated with incident coronary heart disease (CHD) events. However, there is limited research on whether the risk for incident CHD is progressively higher with a higher number of inflammation biomarkers in abnormal levels.

METHODS

We used data from 15,758 Reasons for Geographic and Racial Differences in Stroke (REGARDS) study participants aged ≥45 years without a history of CHD at baseline in 2003-2007. Abnormal levels of baseline high-sensitivity C-reactive protein, leukocyte count and serum albumin were defined as ≥3.8 mg/L (3rd tertile), ≥6.3 x 10⁹ cells/L (3rd tertile), and <4.0 g/dL (1st tertile), respectively. The outcome was a composite of incident myocardial infarction or CHD death.

RESULTS

Overall, 38.9% (n = 6,123) had 0, 36.6% (n = 5,774) had 1, 19.8% (n = 3,113) had 2 and 4.7% (n = 748) had 3 biomarkers of inflammation in abnormal levels. Over a median follow-up of 11.4 years, 954 (6.1%) participants had incident CHD. The rate of incident CHD per 1000 person-years for individuals with 0, 1, 2, and 3 biomarkers of inflammation in abnormal levels was 4.4 (95% confidence interval [CI]: 3.9-5.0), 6.3 (95% CI: 5.6-6.9), 8.8 (95% CI: 7.8-9.9), and 10.6 (95% CI: 8.1-13.1), respectively. Multi-variable adjusted hazard ratios for incident CHD associated with 1, 2 and 3 versus no inflammation biomarker in abnormal levels were 1.26 (95% CI: 1.07-1.49), 1.72 (95% CI: 1.43-2.07), and 1.84 (95% CI: 1.37-2.47), respectively (P-trend < .001).

CONCLUSIONS

The number of inflammation markers in abnormal levels was associated with increased risk of incident CHD after multi-variable adjustment.

Association Between Baseline C-Reactive Protein and the Risk of Lung Cancer: A Prospective Population-Based Cohort Study

C-reactive protein (CRP), a systemic marker of diagnosing chronic inflammation, has been associated with the incidence of multiple types of cancer. However, little is known about the impact of CRP on lung cancer incidence in Chinese population. A total of 97,950 participants without cancer at baseline (2006-2007) of the Kailuan Cohort Study were followed up. The concentration of plasma high-sensitivity CRP (hsCRP) was tested for all participants at baseline interview. Multivariable Cox proportional hazards regression models were used to assess the association between levels of hsCRP and incident lung cancer. During 8.7-year follow-up, 890 incident lung cancer cases occurred and were divided into three groups according to the level of hsCRP. The risk of incident lung cancer was significantly increased with elevated levels of hsCRP [HRMedium/Low, 1.21; 95% confidence interval (CI), 1.03-1.42; HRHigh/Low, 1.42, 95% CI, 1.20-1.68; Ptrend < 0.001], compared with the low group after adjusting confounders. Moreover, after stratifying by BMI, the significantly positive associations between the hsCRP level and the risk of lung cancer were found among those with BMI < 24 (HRHigh/Low, 1.51; 95% CI, 1.18-1.94; Ptrend = 0.001) and BMI = 24-28 (HRHigh/Low, 1.47; 95% CI, 1.13-1.92; Ptrend = 0.003), but not among those with BMI ≥ 28 (HRHigh/Low, 1.01; 95% CI, 0.64-1.57; Ptrend = 0.991). There was an antagonistic interaction between hsCRP levels and BMI that contributed to development of lung cancer (Pinteraction = 0.049). In conclusion, these findings indicate a dose-dependent relationship between hsCRP and lung cancer risk among Chinese population, especially in nonobese participants, suggesting that CRP could serve as a potential biomarker for prediction of lung cancer risk and identification of high-risk population.

PREVENTION RELEVANCE

In this prospective population-based cohort study, we found an association between higher plasma hsCRP and an increased risk of developing lung cancer, with stronger associations observed among nonobese participants.

Transitional changes in the structure of C-reactive protein create highly pro-inflammatory molecules: Therapeutic implications for cardiovascular diseases

C-reactive protein (CRP) is the prototypic acute-phase reactant that has long been recognized almost exclusively as a marker of inflammation and predictor of cardiovascular risk. However, accumulating evidence indicates that CRP is also a direct pathogenic pro-inflammatory mediator in atherosclerosis and cardiovascular diseases. The 'CRP system' consists of at least two protein conformations with distinct pathophysiological functions. The binding of the native, pentameric CRP (pCRP) to activated cell membranes leads to a conformational change resulting in two highly pro-inflammatory isoforms, pCRP* and monomeric CRP (mCRP). The deposition of these pro-inflammatory isoforms has been shown to aggravate the localized tissue injury in a broad range of pathological conditions including atherosclerosis and thrombosis, myocardial infarction, and stroke. Here, we review recent findings on how these structural changes contribute to the inflammatory response and discuss the transitional changes in the structure of CRP as a novel therapeutic target in cardiovascular diseases and overshooting inflammation.

Association of Serum 25(OH)D, Cadmium, CRP With All-Cause, Cause-Specific Mortality: A Prospective Cohort Study

Introduction

To explore the relationship between serum 25(OH)D, cadmium, and CRP with all-cause mortality among people in diabetic and non-diabetic.

Methods

This study used data from the NHANES (2001–2010). Cox regression was used to analyze the relationship between Serum 25(OH)D, cadmium, CRP, and all-cause, cause-specific mortality. We used restricted cubic splines to explore the dose-response relationship between serum 25(OH)D, cadmium, CRP, and all-cause mortality.

Results

During a mean follow-up of 9.1 years, the study included 20,221 participants, 2,945 people with diabetes, and 17,276 people without diabetes. Compared with serum 25(OH)D deficiency group in diabetic patients, the sufficient serum 25(OH)D group was associated with lower all-cause mortality (HR = 0.41, 95%CI 0.28-0.60, P < 0.001) and cardiovascular mortality (HR = 0.46, 95%CI 0.22–0.95, P = 0.04). Compared with the low cadmium group, the high cadmium group was associated with higher all-cause mortality (HR = 1.49, 95%CI 1.06–2.09, P = 0.02). Compared with the low CRP group, the high CRP group was associated with higher all-cause mortality (HR = 1.65, 95%CI 1.24–2.19, P = 0.001) and cancer mortality (HR = 3.25, 95%CI 1.82–5.80, P < 0.001). Restricted cubic splines analysis showed a significant nonlinear association between serum 25(OH)D (P-nonlinearity P < 0.001), cadmium (P-nonlinearity = 0.002), CRP (P-nonlinearity = 0.003), and HR for all-cause mortality risk in diabetic patients. The results were similar among non-diabetic patients, but with different levels of risk. Sensitivity analysis and subgroup analysis presented the results of population studies with different follow-up times, different genders and ages.

Conclusions

In diabetic patients, serum 25(OH)D, cadmium, and CRP were related to all-cause mortality; serum 25(OH)D was related to cardiovascular mortality; CRP was related to cancer mortality. The results were similar among non-diabetic patients, but with different levels of risk.

Application of integrated management bundle incorporating with multidisciplinary measures improved in-hospital outcomes and early survival in geriatric hip fracture patients with perioperative heart failure: a retrospective cohort study

Background

In elderly, hip fracture is often complicated by perioperative heart failure, related to worse prognosis. We aimed to analyze the effects of integrated management bundle incorporating with multidisciplinary measures on in-hospital outcomes and early survival in elderly hip fracture patients with perioperative heart failure.

Methods

In this retrospective cohort study, a total of 421 hip fracture patients aged 65 and over who developed perioperative heart failure were included. According to different perioperative management modes applied, patients were retrospectively divided into multidisciplinary management group (Group A), including 277 patients, and integrated management bundle group (Group B), including 144 patients. The B-type natriuretic peptide (BNP) and C-reactive protein (CRP) levels, complications, length of stay, and hospitalization costs were observed and compared between two groups. Overall survival was compared by Kaplan–Meier methods. Cox regression analysis was used to identify prognostic factors associated with overall survival.

Results

A total of 421 patients were enrolled for analysis, including 277 in Group A and 144 in Group B. BNP and CRP levels were significantly decreased compared with admission (P < 0.05). Furthermore, BNP and CRP in Group B decreased much more than those in Group A (P < 0.05). The reductions were observed in length of stay, hospitalization costs and incidence of pulmonary infection, hypoproteinemia, and acute cerebral infarction in Group B (all P < 0.05). The Kaplan–Meier plots showed significantly superior overall survival in Group B. Integrated management bundle was independent favorable prognostic factors.

Conclusions

The integrated management bundle incorporating with multidisciplinary measures significantly improved the therapeutic effect of perioperative heart failure, reduced inflammatory response, and yielded better hospital outcomes. It brought better survival benefits for geriatric hip fracture patients with perioperative heart failure. The results of this study can play an important role in clinical work and provide a valuable theoretical basis for selection of management model in elderly hip fracture patients with perioperative heart failure.

Genetic analysis of over half a million people characterises C-reactive protein loci

Chronic low-grade inflammation is linked to a multitude of chronic diseases. We report the largest genome-wide association study (GWAS) on C-reactive protein (CRP), a marker of systemic inflammation, in UK Biobank participants (N = 427,367, European descent) and the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) Consortium (total N = 575,531 European descent). We identify 266 independent loci, of which 211 are not previously reported. Gene-set analysis highlighted 42 gene sets associated with CRP levels (p ≤ 3.2 ×10-6) and tissue expression analysis indicated a strong association of CRP related genes with liver and whole blood gene expression. Phenome-wide association study identified 27 clinical outcomes associated with genetically determined CRP and subsequent Mendelian randomisation analyses supported a causal association with schizophrenia, chronic airway obstruction and prostate cancer. Our findings identified genetic loci and functional properties of chronic low-grade inflammation and provided evidence for causal associations with a range of diseases.

Anti-Inflammatory Nutrients and Obesity-Associated Metabolic-Inflammation: State of the Art and Future Direction

Growing evidence supports the hypothesis that dietary factors may play a role in systemic low-grade chronic inflammation. Summary evidence from randomized controlled trials has shown substantial effects on biomarkers of inflammation following the adoption of plant-based diets (including, but not limited to, the Mediterranean diet), while consistent findings have been reported for higher intakes of whole grains, fruits, and vegetables and positive trends observed for the consumption of legumes, pulses, nuts, and olive oil. Among animal food groups, dairy products have been shown to have the best benefits on biomarkers of inflammation, while red meat and egg have been shown to have neutral effects. The present review provides an overview of the mechanisms underlying the relation between dietary factors and immune system, with a focus on specific macronutrient and non-nutrient phytochemicals (polyphenols) and low-grade inflammation. Substantial differences within each macronutrient group may explain the conflicting results obtained regarding foods high in saturated fats and carbohydrates, underlying the role of specific subtypes of molecules (i.e., short-chain fatty acids or fiber vs. long chain fatty acids or free added sugars) when exploring the relation between diet and inflammation, as well as the importance of the food matrix and the commixture of foods in the context of whole dietary patterns. Dietary polyphenols and oligopeptides have been hypothesized to exert several functions, including the regulation of the inflammatory response and effects on the immune system. Overall, evidence suggests that dietary factors may affect the immune system regardless of obesity-related inflammation.

The Benefits of Mindfulness Meditation on Trait Mindfulness, Perceived Stress, Cortisol, and C-Reactive Protein in Nursing Students: A Randomized Controlled Trial

PURPOSE

Mindfulness meditation was used to reduce stress and its responses such as cortisol and C-reactive protein (CRP) among healthy and ill individuals in various cultures, but its effect has not yet been studied among nursing students, experiencing tremendous stress. The objective of this study was to examine the effects of mindfulness meditation on trait mindfulness, perceived stress, serum cortisol, and serum C-reactive proteins (CRP) in nursing students.

PATIENTS AND METHODS

Using a two-arm, randomized, parallel study (conducted in a large university in Jordan, 108 nursing students were randomly assigned to experimental group receiving five 30-minute weekly sessions of mindfulness meditation and control group sitting quiet during the experimental sessions. Trait mindfulness, perceived stress, serum cortisol, and CRP were measured at baseline and end of the intervention.

RESULTS

Using one-way MANOVA and post-hoc comparisons, the results showed that mindfulness meditation was significantly effective in decreasing serum cortisol levels and perceived stress. The mindfulness meditation also decreased CRP and increased trait mindfulness although the results did not reach statistically significant levels.

CONCLUSION

These findings underscore the need for serious consideration of mindfulness meditation in nursing colleges to improve stress and raise immunity in this vulnerable population.

TRIAL REGISTRATION

Mindfulness Meditation for Nursing Students: clinicaltrials.gov, identifier: NCT05099224.

Mendelian Randomization Analysis as a Tool to Gain Insights into Causes of Diseases: A Primer

Many Mendelian randomization (MR) studies have been published recently, with inferences on the causal relationships between risk factors and diseases that have potential implications for clinical research. In nephrology, MR methods have been applied to investigate potential causal relationships of traditional risk factors, lifestyle factors, and biomarkers from omics technologies with kidney function or CKD. This primer summarizes the basic concepts of MR studies, highlighting methods used in recent applications, and emphasizes key elements in conducting and reporting of MR studies that are important for interpreting the results.

Genetically Determined Chronic Low-Grade Inflammation and Hundreds of Health Outcomes in the UK Biobank and the FinnGen Population: A Phenome-Wide Mendelian Randomization Study

Background

C-reactive protein (CRP) has been used as a biomarker of chronic low-grade inflammation in observational studies. We aimed to determine whether genetically determined CRP was associated with hundreds of human phenotypes to guide anti-inflammatory interventions.

Methods

We used individual data from the UK Biobank to perform a phenome-wide two-stage least squares (2SLS) Mendelian randomization (MR) analysis for CRP with 879 diseases. Summary-level data from the FinnGen consortium were utilized to perform phenome-wide two-sample MR analysis on 821 phenotypes. Systematic two-sample MR methods included MR-IVW, MR-WME, MR-Mod, and MR-PRESSO as sensitivity analyses combined with multivariable MR to identify robust associations. Genetic correlation analysis was applied to identify shared genetic risks.

Results

We found genetically determined CRP was robustly associated with 15 diseases in the UK Biobank and 11 diseases in the FinnGen population (P < 0.05 for all MR analyses). CRP was positively associated with tongue cancer, bronchitis, hydronephrosis, and acute pancreatitis and negatively associated with colorectal cancer, colon cancer, cerebral ischemia, electrolyte imbalance, Parkinson's disease, epilepsy, anemia of chronic disease, encephalitis, psychophysical visual disturbances, and aseptic necrosis of bone in the UK Biobank. There were positive associations with impetigo, vascular dementia, bipolar disorders, hypercholesterolemia, vertigo, and neurological diseases, and negative correlations with degenerative macular diseases, metatarsalgia, interstitial lung disease, and idiopathic pulmonary fibrosis, and others. in the FinnGen population. The electrolyte imbalance and anemia of chronic disease in UK Biobank and hypercholesterolemia and neurological diseases in FinnGen pass the FDR corrections. Neurological diseases and bipolar disorders also presented positive genetic correlations with CRP. We found no overlapping causal associations between the populations. Previous causal evidence also failed to support these associations (except for bipolar disorders).

Conclusions

Genetically determined CRP was robustly associated with several diseases in the UK Biobank and the FinnGen population, but could not be replicated, suggesting heterogeneous and non-repeatable effects of CRP across populations. This implies that interventions at CRP are unlikely to result in decreased risk for most human diseases in the general population but may benefit specific high-risk populations. The limited causal evidence and potential double-sided effects remind us to be cautious about CRP interventions.

Systemic inflammation and the relationship between periodontitis, edentulism, and all-cause mortality: A 17-year prospective cohort study

AIM

The aim was to investigate the role of systemic inflammation in the relationship between periodontitis, edentulism, and all-cause mortality in a group of men in Northern Ireland aged 58-72 years.

MATERIALS AND METHODS

A representative sample of 1558 men had a detailed dental examination between 2001 and 2003. The primary end point was death from any cause. Cox's proportional hazards model was used to assess the longitudinal relationship between periodontitis, edentulism, and all-cause mortality. Accelerated failure time modelling was performed to investigate the mediating role of systemic inflammation.

RESULTS

Mean age of the men at baseline was 64.3 (standard deviation 2.9) years. During a median follow-up of 17 years, 500 (32.1%) men died. After adjustment for confounding variables, compared to men with no/mild periodontitis, edentulous men had a hazard ratio for all-cause mortality of 1.52 (95% confidence interval [CI] 1.16-1.99) p < .01 and for those with severe periodontitis, it was 1.34 (95% CI 1.06-1.70) p = .01. Systemic inflammation accounted only for a minor mediating pathway effect of 10%.

CONCLUSIONS

There was evidence in this group of men that those who were edentulous or had severe periodontitis had a significantly increased risk of all-cause mortality. Systemic inflammation was not a major explanatory mediator of this association.

Validity of observational evidence on putative risk and protective factors: appraisal of 3744 meta-analyses on 57 topics

BACKGROUND

The validity of observational studies and their meta-analyses is contested. Here, we aimed to appraise thousands of meta-analyses of observational studies using a pre-specified set of quantitative criteria that assess the significance, amount, consistency, and bias of the evidence. We also aimed to compare results from meta-analyses of observational studies against meta-analyses of randomized controlled trials (RCTs) and Mendelian randomization (MR) studies.

METHODS

We retrieved from PubMed (last update, November 19, 2020) umbrella reviews including meta-analyses of observational studies assessing putative risk or protective factors, regardless of the nature of the exposure and health outcome. We extracted information on 7 quantitative criteria that reflect the level of statistical support, the amount of data, the consistency across different studies, and hints pointing to potential bias. These criteria were level of statistical significance (pre-categorized according to 10^-6, 0.001, and 0.05 p-value thresholds), sample size, statistical significance for the largest study, 95% prediction intervals, between-study heterogeneity, and the results of tests for small study effects and for excess significance.

RESULTS

3744 associations (in 57 umbrella reviews) assessed by a median number of 7 (interquartile range 4 to 11) observational studies were eligible. Most associations were statistically significant at P < 0.05 (61.1%, 2289/3744). Only 2.6% of associations had P < 10^-6, ≥1000 cases (or ≥20,000 participants for continuous factors), P < 0.05 in the largest study, 95% prediction interval excluding the null, and no large between-study heterogeneity, small study effects, or excess significance. Across the 57 topics, large heterogeneity was observed in the proportion of associations fulfilling various quantitative criteria. The quantitative criteria were mostly independent from one another. Across 62 associations assessed in both RCTs and in observational studies, 37.1% had effect estimates in opposite directions and 43.5% had effect estimates differing beyond chance in the two designs. Across 94 comparisons assessed in both MR and observational studies, such discrepancies occurred in 30.8% and 54.7%, respectively.

CONCLUSIONS

Acknowledging that no gold-standard exists to judge whether an observational association is genuine, statistically significant results are common in observational studies, but they are rarely convincing or corroborated by randomized evidence.