Physical activity, C-reactive protein levels and the risk of future coronary artery disease in apparently healthy men and women: the EPIC-Norfolk prospective population study

Sitting Less, Recovering Faster: Investigating the Relationship between Daily Sitting Time and Muscle Recovery following Intense Exercise: A Pilot Study

(1) There is growing concern surrounding the adverse effects of prolonged sitting on health, yet its impact on post-exercise recovery remains relatively unexplored. This study aimed to better understand the potential influence of habitual prolonged sitting on recovery time and the unfavorable impact prolonged sitting may have on time to recovery, as assessed by muscle damage and inflammatory markers and an isokinetic dynamometer. (2) Nine college-age men (mean age ± SD = 22.1 ± 3.1 years, body mass = 80.9 ± 15.7 kg, height = 171 ± 9.0 cm, Body Mass Index (BMI) = 27.6 ± 4.9 kg·m2) participated in an exhaustive exercise protocol. Creatine Kinase (CK), Myoglobin (Mb), C-Reactive Protein (CRP), White Blood Cell Count (WBC), Peak Torque (PT), and muscle soreness were measured at baseline and 0, 24, 48, and 72 h post-exercise. Dietary and exercise logs were maintained during the 5-day testing procedure. (3) No significant differences were observed in muscle damage markers (CK [p = 0.068] and Mb [p = 0.128]), inflammatory markers (CRP [p = 0.814] and WBC [p = 0.140]), or PT [p = 0.255]) at any time point. However, a significant positive correlation was found between daily sitting time and the percent increase in CK concentration from 0 h to 72 h (r = 0.738, p = 0.023). Strong correlations were also noted between prolonged sitting and percent change in Mb concentration at 48 h (r = 0.71, p = 0.033) and 72 h (r = 0.889, p = 0.001). There was a significant two-way interaction for time × velocity (p = 0.043) for PT with a simple main effect for time at 60°·s-1 (p = 0.038). No significant associations were detected between daily carbohydrate or protein intake and recovery markers (p > 0.05). (4) The findings suggest minimizing daily sitting time may expedite and potentially aid muscle recovery after an intense exercise bout, although further research is warranted to validate these findings.

Occupational physical activity: the good, the bad, and the proinflammatory

Background

Physical activity (PA) is beneficial for preventing several conditions associated with underlying chronic inflammation, e. g., cardiovascular disease (CVD) and cancer. While an active lifestyle appears to have anti-inflammatory effects, high levels of occupational PA (OPA) were associated with inflammation and elevated mortality risks. We aimed to summarize the current knowledge (1) on the association between inflammation and OPA and (2) its implications for health and mortality.

Methods and results

This mini-review summarized relevant literature published before January 2023 using established scientific databases and sources. For the primary outcome, observational studies (S) reporting immunological effects (O) in subjects (P), with high (I) vs. low OPA (C), were included. For secondary outcomes, i.e., morbidity and mortality associated with inflammatory processes, (systematic) reviews were included. While "active" occupations and "moderate" OPA appear to have beneficial effects, low (particularly sedentary) and "high-intensity" OPA (particularly including heavy lifting tasks) were associated with inflammation and (CVD and cancer-related) mortality; higher leisure-time PA has been almost consistently associated with lower proinflammatory markers and all-cause mortality risks. Workplace interventions appear to counter some of the observed health effects of unfavorable work strain.

Conclusion

The few studies addressing OPA "intensity" and inflammatory markers are largely heterogeneous regarding OPA classification and confounder control. Sedentary and "heavy" OPA appear to promote proinflammatory effects. In addition to targeted management of work-related physical strain and hazardous environmental co-factors, occupational health providers should focus on employer-initiated exercise interventions and the promotion of leisure-time PA.

Association between C reactive protein and all-cause mortality in the ELSA-Brasil cohort

Background

High-sensitivity C reactive protein (hsCRP) has been proposed as a marker of incident cardiovascular disease and vascular mortality, and may also be a marker of non-vascular mortality. However, most evidence comes from either North American or European cohorts. The present proposal aims to investigate the association of hsCRP with the risk of all-cause mortality in a multiethnic Brazilian population.

Methods

Baseline data (2008–2010) of a cohort of 14 238 subjects participating in the Brazilian Longitudinal Study of Adult Health were used. hsCRP was assayed with immunochemistry. The association of baseline covariates with all-cause mortality was calculated by Cox regression for univariate model and adjusted for different confounders after a mean follow-up of 8.0±1.1 years. The final model was adjusted for age, sex, self-rated race/ethnicity, schooling, health behaviours and prevalent chronic disease.

Results

The risk of death increased steadily by quartiles of hsCRP, from 1.45 (95% CI 1.05 to 2.01) in quartile 2 to 1.95 (95% CI 1.42 to 2.69) in quartile 4, compared with quartile 1. Furthermore, the persistence of a significant graded association after the exclusion of deaths in the first year of follow-up suggests that these results are unlikely to be due to reverse causality. Finally, the HR was unaffected by the exclusion of participants who had self-reported medical history of diabetes, cancer and chronic obstructive pulmonary disease.

Conclusions

Our study shows that hsCRP level is associated with mortality in a highly admixed population, independent of a large set of lifestyle and clinical variables.

Does replacing sedentary behaviour with light or moderate to vigorous physical activity modulate inflammatory status in adults?

BACKGROUND

Sedentary behaviour, obesity and insulin resistance are associated with pro-inflammatory status. Limited data on whether physical activity modulates inflammatory status and counteracts obesity and insulin resistance associated low-grade inflammation exist. Our objective was to investigate associations between objectively measured physical activity and inflammatory status, and specifically whether substituting daily sedentary behaviour with light activity or moderate to vigorous physical activity (MVPA), is associated with beneficial alterations to the inflammatory profile among middle-aged adults and those at increased cardiometabolic risk (obese and insulin resistant subjects).

METHODS

Data are from a sub-sample of the Mitchelstown cohort; a population-based cross-sectional sample of 2047 Irish adults. Physical activity intensity and duration were measured in 396 participants for 7-consecutive days using the GENEActiv accelerometer. Isotemporal regression analysis examined the associations between replacing 30 min per day of sedentary behaviour with equal amounts of light activity and MVPA on inflammatory factors (serum acute-phase reactants, adipocytokines, pro-inflammatory cytokines and white blood cells (WBC)).

RESULTS

Reallocating 30 min of sedentary time with MVPA was associated with a more favourable inflammatory profile characterized by higher adiponectin and lower complement component C3 (C3), leptin, interleukin 6 (IL-6) and WBC concentrations (P < 0.05). No significant effects were noted with substitution of sedentary time with light activity. Among the obese subjects replacing sedentary behaviour with an equivalent amount of MVPA was associated with lower WBC counts (P < 0.05); no associations were detected among the insulin resistant (HOMA-IR >75th percentile) subjects. Among the non-obese and non-insulin resistant subjects substituting 30 min of sedentary behaviour with MVPA was associated with decreased C3, IL-6 and WBC concentrations.

CONCLUSIONS

Replacing sedentary behaviour with MVPA modulates pro-inflammatory status. These findings, which highlight the need for the developing randomized trials aimed at lowering cardiometabolic risk, warrant further investigation.

Red cell distribution width is associated with physical inactivity and heart failure, independent of established risk factors, inflammation or iron metabolism; the EPIC-Norfolk study

AIMS

Red cell distribution width (RDW) is associated with increased risk of heart failure (HF). We examined in a healthy population (1) whether this association is independent of cardiovascular risk factors and iron metabolism and (2) whether RDW associates with physical activity.

METHODS AND RESULTS

Hazard ratios (HRs, highest quartile versus lowest quartile of RDW) for the risk of HF were calculated in 17,533 participants from the European Prospective Investigation into Cancer and Nutrition (EPIC)-Norfolk cohort. During a follow-up of 11.2±2.2 years 640 participants developed a HF event. The HR for HF events was 1.44 (95%CI 1.15-1.80, p<0.001). There was a non-linear increase in HF risk across RDW quartiles. Adjustment for established risk factors (sex, age, diabetes, smoking, systolic blood pressure, total and high-density lipoprotein cholesterol) attenuated the HR for HF to 1.40 (95%CI 1.11-1.77, p=0.001). Adjustment for CRP, iron and ferritin levels did not affect the HR for HF. RDW levels are inversely associated with physical activity (per category β=-0.37, 95%CI -0.053 to -0.021, p<0.0001), independent of iron metabolism. However, the association between HF and RDW levels was not changed by physical activity.

CONCLUSIONS

This study confirms that RDW is associated with HF events in an apparently healthy middle-aged population. More importantly, we show that the underlying pathophysiology linking HF with anisocytosis is not reflected by conventional risk factors, nor it is explained by iron metabolism or inflammation. Furthermore, RDW levels were associated with physical inactivity, but this did not influence the RDW-associated-risk of heart failure.

Impact of physical activity on inflammation: effects on cardiovascular disease risk and other inflammatory conditions

Since the 19(th) century, many studies have enlightened the role of inflammation in atherosclerosis, changing our perception of "vessel plaque due to oxidized lipoproteins", similar to a "rusted pipe", towards a disease with involvement of many cell types and cytokines with more complex mechanisms. Although "physical activity" and "physical exercise" are two terms with some differences in meaning, compared to sedentary lifestyle, active people have lower cardiovascular risk and lower inflammatory markers. Activities of skeletal muscle reveal "myokines" which have roles in both the immune system and adipose tissue metabolism. In vitro and ex-vivo studies have shown beneficial effects of exercise on inflammation markers. Meanwhile in clinical studies, some conflicting results suggested that type of activity, exercise duration, body composition, gender, race and age may modulate anti-inflammatory effects of physical exercise. Medical data on patients with inflammatory diseases have shown beneficial effects of exercise on disease activity scores, patient well-being and inflammatory markers. Although the most beneficial type of activity and the most relevant patient group for anti-inflammatory benefits are still not clear, studies in elderly and adult people generally support anti-inflammatory effects of physical activity and moderate exercise could be advised to patients with cardiovascular risk such as patients with metabolic syndrome.

Vigorous physical activity, mediating biomarkers, and risk of myocardial infarction

PURPOSE

The effects of physical activity on risk of myocardial infarction (MI) are well documented and may include beneficial changes in blood lipids, inflammatory markers, and insulin sensitivity. The degree to which these and other traditional and nontraditional cardiovascular biomarkers mediate the inverse association between physical activity and risk of MI in men remains unclear.

METHODS

We conducted a nested case-control study among 18,225 men in the Health Professionals Follow-up Study followed from 1994 to 2004. A total of 412 men with incident MI were matched 1:2 with control participants on age and smoking status using risk-set sampling. From detailed responses to a modified Paffenbarger physical activity questionnaire, we determined the association between average hours of vigorous-intensity activity (activities requiring METs ≥ 6) and MI risk.

RESULTS

For a 3-h·wk(-1) increase in vigorous-intensity activity, the multivariate relative risk (RR) of MI was 0.78 (95% confidence interval (CI) = 0.61-0.98). In models including preexisting CVD-related conditions, further adjustment for HDL-C, vitamin D, apolipoprotein B, and hemoglobin A1c attenuated the RR by 70% (95% CI = 12%-127%) to an RR of 0.93 (95% CI = 0.72-1.19).

CONCLUSIONS

Participating in 3 h·wk(-1) of vigorous-intensity activity is associated with a 22% lower risk of MI among men. This inverse association can be partially explained by the beneficial effects of physical activity on HDL-C, vitamin D, apolipoprotein B, and hemoglobin A1c. Although the inverse association attributable to these biomarkers is substantial, future research should explore benefits of exercise beyond these biomarkers of risk.

High intensity interval training reduces systemic inflammation in post-PCI patients

BACKGROUND

Increased plasma levels of inflammatory markers and markers of endothelial cell activation have been associated with increased risk for cardiovascular events. Exercise training may lower the risk for coronary heart disease by attenuating inflammation and improving endothelial function. The objective of this study was to evaluate effects of regular high-intensity exercise training on a wide range of markers of inflammation and endothelial cell activation.

MATERIALS AND METHODS

Consecutively, 40 patients were prospectively randomized to a 6 months supervised high-intensity interval training programme or to a control group following successful percutaneous coronary intervention (PCI). Blood samples of 36 patients with stable angina, drawn at baseline (before PCI) and at 6 months, were analysed. Late luminal loss was measured at 6 months using quantitative coronary angiography.

RESULTS

At 6 months, levels of the inflammatory markers interleukin (IL)-6 and IL-8 were reduced and levels of the anti-inflammatory cytokine IL-10 increased in the training group only. The decrease in IL-6 and C-reactive protein levels were significantly correlated with the decrease in luminal loss following PCI. In contrast to these anti-inflammatory effects, training had no effect on markers of platelet-mediated inflammation, and the effect of training on markers on endothelial cell activation were rather complex showing attenuating (von Willebrand factor) and enhancing (E-selectin and vascular cell adhesion molecule 1) effects.

CONCLUSIONS

Regular exercise training in stable angina patients following PCI may attenuate some, but not all, inflammatory pathways, potentially contributing to the beneficial effects of exercise training on restenosis.

Physical activity and risk of cardiovascular disease events: inflammatory and metabolic mechanisms

PURPOSE

The biological mechanisms through which physical activity lowers the risk of cardiovascular disease (CVD) are incompletely understood. We examined the extent to which inflammatory/hemostatic factors (C-reactive protein and fibrinogen), metabolic factors (adiposity, total cholesterol, and HDL cholesterol), and hypertension mediate the association between physical activity and risk of CVD events.

METHODS

Data were collected from a nationally representative sample of 7881 men and women that were linked to a patient-based database of CVD hospital admissions and deaths up to September 2006.

RESULTS

A total of 226 incident CVD events (64 fatal) occurred over an average follow-up of 7.2 yr. The risk of CVD decreased in relation to physical activity groups according to current recommendations (at least 30 min of moderate activity five times per week or vigorous activity three times per week). The lowest risks for CVD were seen in participants meeting the recommendations through undertaking vigorous activity (hazard ratio = 0.47, 95% CI = 0.22-0.99), although being physically active below the guidelines also conferred protection (hazard ratio = 0.57, 0.42-0.77). Biological risk factors collectively explained between 39.4% and 22.6% of the cardioprotective effects of moderate and vigorous physical activity, respectively. Inflammation and hypertension tended to explain the largest proportion of variance.

CONCLUSIONS

Participation in any physical activity, irrespective of meeting current guidelines, was associated with a lower risk of CVD. The inverse association between physical activity and CVD risk is partly mediated by biological risk factors.

Lipoprotein-associated phospholipase A2, C-reactive protein, and coronary artery disease in individuals with type 1 diabetes and macroalbuminuria

Given the paucity of data in type 1 diabetes concerning lipoprotein-associated phospholipase A( 2) (Lp-PLA(2)), we examined its prospective relationship with coronary artery disease (CAD), as well as the effect of modification by C-reactive protein (CRP) and haptoglobin genotype, in individuals with type 1 diabetes who are at an increased risk for CAD due to also having macroalbuminuria (n=96). Although Lp-PLA(2) activity was univariately predictive of CAD (HR=1.54 per SD, p=0.009), this relationship was not significant after covariate adjustment (p=0.59). There was a significant interaction between Lp-PLA(2) and CRP (p=0.02), i.e. those with both markers greater than the median level were more likely to have a CAD event than those persons with low levels of both (HR=2.89, p=0.06). When stratified by haptoglobin genotype, Lp-PLA(2) was predictive of CAD in persons with the 2/1 (HR=2.40, p=0.05), but not 2/2 (HR=0.66, p=0.27), genotype. The association between Lp-PLA(2) activity and CAD differs by CRP and haptoglobin genotype in this group of persons with type 1 diabetes and macroalbuminuria.

'Lone' increase in C-reactive protein after cardiac surgery: prevalence, clinical characteristics, in-hospital course, and prognostic value

BACKGROUND

Serum C-reactive protein (CRP) is involved in the acute phase reaction after surgery, even though its clinical significance remains a matter of debate. We evaluated CRP levels in cardiac surgery patients without clinical or laboratory signs of infection.

METHODS

We screened 737 consecutive patients referred to our center 8+/-5 days after cardiac surgery. Patients with fever (>37.2 degrees C), elevated white blood cell count (>11,000/ml), neutrophilia (>70%), or any inflammatory, infective or malignant disease were excluded. CRP levels were measured on admission and at discharge and the values were related to the following variables: age, sex, diabetes mellitus, renal failure, type of surgery, postoperative atrial fibrillation, pericardial or pleural effusion, and length of hospital stay. Follow-up (mean: 23+/-8.5 months) was available for 175 patients (94%).

RESULTS

In the 187 patients enrolled in the study, the CRP values were significantly elevated (median: 4.23 mg/dl, interquartiles range: 2.68-6.64) independent of any variable analyzed. At discharge, CRP levels were significantly reduced compared with values on admission (median: 1.55 mg/dl, interquartiles range: 0.84-2.37, P<0.001). At follow-up, 19 events (10.8%) occurred (two noncardiac deaths, 17 hospital readmissions for cardiac reasons); nonetheless, no correlation was found with CRP values either on admission or at discharge.

CONCLUSION

Early after cardiac surgery, in patients without clinical or laboratory signs of acute infection, CRP levels are significantly elevated, do not correlate with clinical variables, and decrease at discharge. These findings suggest a systemic inflammatory response to surgery-related stress, which carries a favorable prognosis at follow-up.

Major depression, C-reactive protein, and incident ischemic heart disease in healthy men and women

OBJECTIVE

To investigate how C-reactive protein (CRP) and major depressive disorder (MDD) relate to each other and to incident ischemic heart disease (IHD). Studies have shown that both depression and raised CRP concentration predict IHD and that elevated CRP is linked with increased risk of depression.

METHODS

A prospective case-control study of healthy men and women, aged 45 to 79 years, was undertaken within the United Kingdom European Prospective Investigation into Cancer (EPIC)-Norfolk study. CRP concentration was measured for 726 (fatal or nonfatal) IHD cases and 1688 matched controls who completed a baseline MDD self-assessment, defined by restricted Diagnostic and Statistical Manual of Mental Disorders, 4th Edition diagnostic criteria.

RESULTS

Past-year MDD was associated with increased CRP concentration levels (4.31 mg/L for participants who reported episodes of MDD in the past year versus 3.65 mg/L for those who did not; p = .003), and the odds ratio for incident IHD associated with higher CRP concentration was 2.02 (comparing the top versus bottom quartile of CRP; 95% Confidence Interval (CI) = 1.52-2.68), adjusted for cigarette smoking, diabetes, systolic blood pressure, body mass index, and cholesterol. The association between past-year MDD and IHD was independent of CRP (odds ratio = 1.55; 95% CI = 1.01-2.37, with adjustments as above, and additionally for CRP).

CONCLUSIONS

Evidence from this study is supportive of an association between MDD and CRP although it suggests that CRP does not account for the association between MDD and future IHD.