What predicts the occurrence of the metabolic syndrome in a population-based cohort of adult healthy subjects?

Association Between High-Sensitivity C-Reactive Protein and Metabolic Syndrome Among Hispanic/Latino Participants of the Hispanic Community Health Study/Study of Latinos

Purpose: To determine whether high-sensitivity C-reactive protein (hsCRP) is associated with incident Metabolic Syndrome (MetS) among U.S. Hispanic/Latino adults. Patients and Methods: The Hispanic Community Health Study/Study of Latinos is a longitudinal observational cohort assessing cardiovascular health among diverse U.S. Hispanic/Latino adults. hsCRP was measured at visit 1 (2008-2011) and classified as low, moderate, or high, based on the Centers for Disease Control and Prevention and American Heart Association (CDC/AHA) guidelines. All MetS components [abdominal obesity, triglycerides, high-density lipoprotein (HDL) cholesterol, blood pressure, and fasting glucose] were measured at visit 1 and visit 2 (2014-2017). MetS was defined as the presence of three or more components based on the 2005 definition from the modified Third Report of the National Cholesterol Education Program Adult Treatment Panel (modified NCEP ATP III). Participants free of MetS at visit 1 and with complete data on hsCRP and all MetS components were included (n = 6121 participants). We used Poisson regression analysis to determine whether hsCRP was associated with incident MetS after adjusting for demographic, behavioral, and clinical factors. All analyses accounted for the complex survey design of the study. Results: In fully adjusted models, moderate versus low hsCRP was associated with a 33% increased risk of MetS [incidence rate ratio (IRR): 1.33, 95% confidence interval (CI): 1.10-1.61], while high versus low hsCRP was associated with a 89% increased risk of MetS (IRR: 1.89, 95% CI: 1.58-2.25). Conclusions: Greater levels of hsCRP were associated with new onset of MetS in a diverse sample of U.S. Hispanic/Latino adults. Results suggest that hsCRP may be an independent risk factor for MetS.

Association between baseline and changes in high-sensitive C-reactive protein and metabolic syndrome: a nationwide cohort study and meta-analysis

BACKGROUND

We aimed to prospectively evaluate the associations between the baseline and changes in high-density C-reactive protein (hs-CRP) and incident metabolic syndrome (MetS) in China and update the evidence based on a meta-analysis of cohort studies in different populations.

METHODS

Data from the China Health and Retirement Longitudinal Study among adults aged 45 years or older were analyzed. Participants who were recruited in the study in 2011-2012 without MetS and successfully followed up to 2015-2016 were included in our final analysis. Logistic regressions were applied to examine the prospective associations of baseline and changes in hs-CRP with incident MetS and estimate corresponding odds ratios (ORs) and 95% confidence intervals (95% CIs). A meta-analysis was conducted to synthesize effect estimates from our findings and other cohort studies on this topic.

RESULTS

Among 4,116 participants, 535 developed MetS after a 4-year follow-up. Compared with the participants with hs-CRP in the lowest quartile, those with hs-CRP in the second, third, and highest quartiles had higher odds of MetS, with multivariable-adjusted ORs (95% CIs) of 1.51 (1.12, 2.06), 1.50 (1.11, 2.04), and 1.83 (1.37, 2.47). For the hs-CRP changes, ORs (95% CIs) were 3.24 (2.51, 4.02), 3.34 (2.56, 4.38), and 3.34 (2.54, 4.40) respectively. One unit (log of 1 mg/L) increase in hs-CRP was associated with 23% higher risk of MetS (OR 1.23; 95% CI 1.10, 1.38). In a meta-analysis of 6 cohort studies, the pooled relative risk for MetS was 1.63 (1.38, 1.93) for the highest versus lowest level of hs-CRP. In addition, the pooled relative risk for MetS was 1.29 (1.05, 1.59) for each unit increase of hs-CRP after log-transformation.

CONCLUSIONS

Both higher baseline hs-CRP and longitudinal hs-CRP increases were associated with higher risks of incident MetS. Individuals with high hs-CRP levels may need to be closely monitored for future risk of MetS.

Obesity is an independent determinant of elevated C-reactive protein in healthy women but not men

BACKGROUND AND AIMS

High-sensitivity C-reactive protein (hs CRP) has emerged as an inflammatory biomarker to predict metabolic syndrome. Here, we investigate the association of hs CRP with metabolic variables and determine the risks for elevated hs CRP levels in healthy Singaporean adults.

METHODS

We conducted a cross-sectional study of 225 participants (104 men). The levels of hs CRP and fasting lipid parameters were analyzed by COBAS. Body composition was determined with dual-energy X-ray absorptiometry.

RESULTS

Twenty-one (9 %) participants had elevated hs CRP levels (>3 mg/mL). The levels of hs CRP had significant correlations (p <0.05) with obesity and metabolic variables among women. Stepwise multivariate regression analysis identified FM (%) (accounted for 22.5% of the variability in hs CRP levels) as a major determinant of hs CRP levels. On multivariate regression, FM (%) was the independent determinant of intermediate and elevated hs CRP in women after adjustment for the potential confounders.

CONCLUSIONS

Obesity may play a direct role in the elevated hs CRP levels in women, but not men living in Singapore. This is probably due to different body composition or different effects of sex hormones on adipose tissue between men and women.

Biomarkers of Metabolic Syndrome: Biochemical Background and Clinical Significance

Biomarkers of the metabolic syndrome are divided into four subgroups. Although dividing them in groups has some limitations, it can be used to draw some conclusions. In a first part, the dyslipidemias and markers of oxidative stress are discussed, while inflammatory markers and cardiometabolic biomarkers are reviewed in a second part. For most of them, the biochemical background and clinical significance are discussed, although here also a well-cut separation cannot always be made. Altered levels cannot always be claimed as the cause, risk, or consequence of the syndrome. Several factors are interrelated to each other and act in a concerted, antagonistic, synergistic, or modulating way. Most important conclusions are summarized at the end of every reviewed subgroup. Genetic biomarkers or influences of various food components on concentration levels are not included in this review article.

Association of C-Reactive Protein and Metabolic Disorder in a Chinese Population

Objective: To assess the high-sensitivity C-reactive protein (hs-CRP) levels and explore the risk factors for an elevated hs-CRP level. We also provide the clinical utility of CRP to identify subjects with metabolic syndrome (MetS). Methods: Data were drawn from a cross-sectional survey in China. Subjects were divided into three subgroups: hs-CRP ≤ 1 mg/L, 1 mg/L < hs-CRP ≤ 3 mg/L and hs-CRP > 3 mg/L. Multiple linear regressions and logistic regression models were used. Results: In the Chinese population, 50.43% subjects had a low hs-CRP level, 30.21% subjects had an intermediate hs-CRP level and 19.36% subjects had an elevated hs-CRP level. Age, physical inactivity, abdominal obesity, a low LDL level, an elevated fasting glucose level, uric acid and urinary albumin to creatinine ratio (ACR) were correlated with log-CRP. In multivariate analysis, relative risks of an elevated CRP level were 2.40 (95% CI 1.44–3.99, p = 0.001), 3.63 (95% CI 2.20–5.98, p < 0.001), 4.23 (95% CI 2.51–7.11, p < 0.001) and 6.23 (95% CI 3.45–11.26, p < 0.001) for subjects with 1, 2, 3, or more than 3 MetS components, respectively. The accurate estimates of the area under the receiver operating characteristic of hs-CRP for MetS was 0.6954 (95% CI, 0.67–0.72). Conclusion: Age, physical inactivity, abdominal obesity, a low LDL level, an elevated fasting glucose level, uric acid and ACR are correlated with log-CRP. The number of MetS components is a significant determinant of elevated CRP levels after adjusted for other potential confounders.

Clinical biomarkers in metabolic syndrome

A biomarker can be defined as a measurable variable that may be used as an indicator of a given biological state or condition. Biomarkers have been used in health and disease for diagnostic purposes, as tools to assess effectiveness of nutritional or drug intervention, or as risk markers to predict the development of certain diseases. In nutrition studies, selecting appropriate biomarkers is important to assess compliance, or incidence of a particular dietary component in the biochemistry of the organism, and in the diagnosis and prognosis of nutrition-related diseases. Metabolic syndrome is a cluster of cardiovascular risk factors that occur simultaneously in the same individual, and it is associated with systemic alterations that may involve several organs and tissues. Given its close association with obesity and the increasing prevalence of obesity worldwide, identifying obese individuals at risk for metabolic syndrome is a major clinical priority. Biomarkers for metabolic syndrome are therefore potential important tools to maximize the effectiveness of treatment in subjects who would likely benefit the most. Choice of biomarkers may be challenging due to the complexity of the syndrome, and this article will mainly focus on nutrition biomarkers related to the diagnosis and prognosis of the metabolic syndrome.

Few favorable associations between fruit and vegetable intake and biomarkers for chronic disease risk in American adults

Using 24-hour dietary recall data from the National Health and Nutrition Examination Survey 1999 to 2006, the possible link between fruit and vegetable intake and chronic disease risk was assessed. C-reactive protein (CRP), low-density lipoprotein cholesterol, high-density lipoprotein cholesterol (HDL-C), fasting plasma glucose (FPG), total cholesterol, and glycosylated hemoglobin were selected as biomarkers for chronic disease risk. It is hypothesized that individuals who consume more fruits and vegetables will have reduced chronic disease risk because of the healthful benefits of these foods. The objective of this study was to examine the relationship between fruit and vegetable consumption on selected biomarkers for chronic disease risk. Although some associations were significant for FPG, HDL-C, and low-density lipoprotein cholesterol in some of the models, no trend was present. After adjusting for demographic factors, socioeconomic factors, lifestyle factors, body mass index, total energy intake, and the presence of at least 1 of our 5 predetermined comorbidities, no associations of reduced or increased risk were observed in any quartiles of combined fruit and vegetable intake. Fruit and vegetable intakes were weakly associated with an increased HDL-C level and decreased FPG, glycosylated hemoglobin, and C-reactive protein levels in some of the models; however, no association was observed in the final model. Because selected biomarkers of future disease risk remained in reference ranges at both high and low intake and no significance was observed in the final model, no protective association was observed between fruit and vegetable intake and biomarkers for chronic disease risk. However, fruit and vegetable consumption is recommended as part of an overall healthy diet and to displace other energy-dense foods for weight maintenance, which can lead to a decrease in future disease risk.

Effects of lifestyle interventions on inflammatory markers in the metabolic syndrome

Metabolic syndrome (MetS) is a clustering of cardiovascular risk factors which places individuals at increased risk for cardiovascular morbidity and mortality. In addition to obesity and insulin resistance, inflammation is emerging as a potential etiologic factor of the syndrome. One hypothesis suggests that obesity contributes to insulin resistance through increased production of adipose-derived inflammatory cytokines. Currently, lifestyle change is the first line of treatment for MetS. Only recently, however, have studies begun exploring the effect of lifestyle interventions on the mediation of inflammation in individuals with MetS. This review summarizes the strongest evidence (i.e. randomized controlled trial data) for a role of lifestyle interventions (diet and/or exercise) on the improvement of inflammatory biomarkers in people with MetS. Of six studies assessed, lifestyle interventions were consistently successful at improving the inflammatory and metabolic profiles. Interestingly, improvements in the inflammatory profile were found to be largely independent of obesity. Data currently suggest that alterations in dietary composition may be the most effective lifestyle change, although there is a need for more research in this area.

Worksite health screening programs for predicting the development of Metabolic Syndrome in middle-aged employees: a five-year follow-up study

BACKGROUND

Metabolic syndrome (MetS) management programs conventionally focus on the adults having MetS. However, risk assessment for MetS development is also important for many adults potentially at risk but do not yet fulfill MetS criteria at screening. Therefore, we conducted this follow-up study to explore whether initial screening records can be efficiently applied on the prediction of the MetS occurrence in healthy middle-aged employees.

METHODS

Utilizing health examination data, a five-year follow-up observational study was conducted for 1384 middle-aged Taiwanese employees not fulfilling MetS criteria. Data analyzed included: gender, age, MetS components, uric acid, insulin, liver enzymes, sonographic fatty liver, hepatovirus infections and lifestyle factors. Multivariate logistic regression was used to estimate the adjusted odds ratios (OR) and 95% confidence interval (CI) of risk for MetS development. The synergistic index (SI) values and their confidence intervals of risk factor combinations were calculated; and were used to estimate the interacting effects of coupling MetS components on MetS development.

RESULTS

Within five years, 13% (175 out of 1384) participants fulfilled MetS criteria. The ORs for MetS development among adults initially having one or two MetS components were 2.8 and 7.3, respectively (both p < 0.01), versus the adults having zero MetS component count at screening. Central obesity carried an OR of 7.5 (p < 0.01), which far exceeded other risk factors (all ORs < 2.7). Synergistic effects on MetS development existed between coupling MetS components: 1. High blood pressure plus low-HDL demonstrated an OR of 11.7 (p < 0.01) for MetS development and an SI of 4.7 (95% CI, 2.1-10.9). 2. High blood pressure plus hyperglycemia had an OR of 7.9 (p < 0.01), and an SI of 2.7 (95% CI, 1.2-6.4).

CONCLUSION

MetS component count and combination can be used in predicting MetS development for participants potentially at risk. Worksite MetS screening programs simultaneously allow for finding out cases and for assessing risk of MetS development.

The metabolic syndrome in older persons

The metabolic syndrome is one of several patterns of risk for atherosclerotic cardiovascular disease. Although the concept of the metabolic syndrome has been known for 2 centuries or more, it is only recently that its individual components have been proposed. Visceral obesity is a central component but other major facets such as hypertension, dyslipidemia, or dysglycemia are often present. These components are well-established cardiovascular risk factors and therefore grouping them under a single entity, namely the metabolic syndrome, has questioned its clinical usefulness and its ability to predict cardiovascular disease. Depending on what criteria are used, the prevalence of this syndrome may be as much as 40% in those aged 60 years and older. Heredity, environmental factors, personal lifestyle habits and behavior, and clinical comorbidities all seem to be associated with the metabolic syndrome. In addition, hypogonadism in men and hypovitaminosis D are age-related issues associated with the metabolic syndrome. In ageing individuals the existence of the metabolic syndrome as a distinct entity is questioned although some studies report an association with diabetes mellitus, physical impairments, and cognitive dysfunction. Further studies that explore these factors over time are needed but for now, treatment remains focused on individual components and not on the syndrome as a whole.