A survey of 246 suggested coronary risk factors

A literature review of quality assessment and applicability to HTA of risk prediction models of coronary heart disease in patients with diabetes

This literature review had two objectives: to identify models for predicting the risk of coronary heart diseases in patients with diabetes (DM); and to assess model quality in terms of risk of bias (RoB) and applicability for the purpose of health technology assessment (HTA). We undertook a targeted review of journal articles published in English, Dutch, Chinese, or Spanish in 5 databases from 1st January 2016 to 18th December 2022, and searched three systematic reviews for the models published after 2012. We used PROBAST (Prediction model Risk Of Bias Assessment Tool) to assess RoB, and used findings from Betts et al. 2019, which summarized recommendations and criticisms of HTA agencies on cardiovascular risk prediction models, to assess model applicability for the purpose of HTA. As a result, 71 % and 67 % models reporting C-index showed good discrimination abilities (C-index >= 0.7). Of the 26 model studies and 30 models identified, only one model study showed low RoB in all domains, and no model was fully applicable for HTA. Since the major cause of high RoB is inappropriate use of analysis method, we advise clinicians to carefully examine the model performance declared by model developers, and to trust a model if all PROBAST domains except analysis show low RoB and at least one validation study conducted in the same setting (e.g. country) is available. Moreover, since general model applicability is not informative for HTA, novel adapted tools may need to be developed.

Multifunctional nanoparticle-mediated combining therapy for human diseases

Combining existing drug therapy is essential in developing new therapeutic agents in disease prevention and treatment. In preclinical investigations, combined effect of certain known drugs has been well established in treating extensive human diseases. Attributed to synergistic effects by targeting various disease pathways and advantages, such as reduced administration dose, decreased toxicity, and alleviated drug resistance, combinatorial treatment is now being pursued by delivering therapeutic agents to combat major clinical illnesses, such as cancer, atherosclerosis, pulmonary hypertension, myocarditis, rheumatoid arthritis, inflammatory bowel disease, metabolic disorders and neurodegenerative diseases. Combinatorial therapy involves combining or co-delivering two or more drugs for treating a specific disease. Nanoparticle (NP)-mediated drug delivery systems, i.e., liposomal NPs, polymeric NPs and nanocrystals, are of great interest in combinatorial therapy for a wide range of disorders due to targeted drug delivery, extended drug release, and higher drug stability to avoid rapid clearance at infected areas. This review summarizes various targets of diseases, preclinical or clinically approved drug combinations and the development of multifunctional NPs for combining therapy and emphasizes combinatorial therapeutic strategies based on drug delivery for treating severe clinical diseases. Ultimately, we discuss the challenging of developing NP-codelivery and translation and provide potential approaches to address the limitations. This review offers a comprehensive overview for recent cutting-edge and challenging in developing NP-mediated combination therapy for human diseases.

Acid suppressants use and risk of atherosclerotic cardiovascular disease in middle-aged and older adults

BACKGROUND AND AIMS

Concerns regarding adverse events associated with the use of acid suppressants have increased. However, the impact of proton pump inhibitors (PPIs) and histamine-2 receptor antagonists (H2RAs) on the risk of atherosclerotic cardiovascular disease (ASCVD) remains unknown. This study aimed to estimate the risk of ASCVD in association with the use of PPIs and H2RAs.

METHODS

This prospective cohort study included participants without cardiovascular diseases or anti-hypertensive treatment at baseline (2006-2010) in the UK Biobank. The outcomes were ASCVD and each subtype (coronary artery disease, myocardial infarction, peripheral artery disease, and ischemic stroke). The association was estimated by Cox proportional-hazards models.

RESULTS

Among 316,730 individuals (aged 50-88 years), during a median of 12.5 years of follow-up, we documented 13,503 (4.3%) incident ASCVD. Regular PPIs use was associated with a higher risk of ASCVD (HR: 1.16, 95% CI: 1.09-1.23) and every subtype of ASCVD. Among each type of PPIs, omeprazole (HR: 1.19, 95% CI: 1.11-1.28), lansoprazole (HR: 1.11, 95% CI: 1.02-1.22), and pantoprazole (HR: 1.40, 95% CI: 1.00-1.97) were associated with a higher risk of ASCVD. Stratification analysis showed that PPIs use was associated with a higher risk of ASCVD among individuals without indications of medications for PPIs. In addition, use of H2RAs was not related to the risk of ASCVD (HR: 0.97, 95% CI: 0.85-1.11).

CONCLUSIONS

PPIs were associated with increased risk of ASCVD, particularly amongst participants without indications for medication. Our findings are of important practical significance and suggest that clinicians should be cautious in prophylactic use of PPIs.

Genetics of Cardiovascular Disease: How Far Are We from Personalized CVD Risk Prediction and Management?

Despite the rapid progress in diagnosis and treatment of cardiovascular disease (CVD), this disease remains a major cause of mortality and morbidity. Recent progress over the last two decades in the field of molecular genetics, especially with new tools such as genome-wide association studies, has helped to identify new genes and their variants, which can be used for calculations of risk, prediction of treatment efficacy, or detection of subjects prone to drug side effects. Although the use of genetic risk scores further improves CVD prediction, the significance is not unambiguous, and some subjects at risk remain undetected. Further research directions should focus on the "second level" of genetic information, namely, regulatory molecules (miRNAs) and epigenetic changes, predominantly DNA methylation and gene-environment interactions.

Experimental Agents for the Treatment of Atherosclerosis: New Directions

Cardiovascular and related metabolic disorders constitute a worldwide health challenge. Atherosclerosis is a chronic inflammatory condition based on both dyslipidemia and inflammation. Therefore, even when dyslipidemia is controlled, the risk of atherosclerosis remains. Among the most efficient inflammatory mediators used as therapeutic tools in cardiovascular disease are the interleukins, which are pro-inflammatory mediators like cytokines. Moreover, a protein kinase inhibitors, p38 mitogen-activated protein kinase (MAPK) inhibitor, and an inhibitor of a leukocyte adhesion molecule, P-Selectin, have also presented therapeutic potential for this disorder. Colchicine, being an inexpensive therapeutic option, has been proved to be suitable for the prevention of atherosclerosis. In this review, we summarize all the studies, from 2010 to 2020, in which treatment approaches based on the agents mentioned above are evaluated in the management of atherosclerosis.

Epigenetic control of atherosclerosis via DNA methylation: A new therapeutic target?

Atherosclerosis is a disease in which lipid-laden plaques are developed inside the vessel walls of arteries. The immune system is activated, resulting in inflammation and oxidative stress. Endothelial cells (ECs) are activated, arterial smooth muscle cells (SMCs) proliferate, macrophages are activated, and foam cells are developed, leading to dysfunctional ECs. Epigenetic regulatory mechanisms, including DNA methylation, histone modifications, and microRNAs are involved in the modulation of genes that play distinct roles in several aspects of cell biology and physiology, hence linking environmental stimuli to gene regulation. Recent research has investigated the involvement of DNA methylation in the etiopathogenesis of atherosclerosis, and several studies have documented the role of this mechanism in various aspects of the disease. Regulation of DNA methylation plays a critical role in the integrity of ECs, SMC proliferation and formation of atherosclerotic lesions. In this review, we seek to clarify the role of DNA methylation in the development of atherosclerosis through different mechanisms.

Correlation without a cause: an epidemiological odyssey

In the 1980s debate intensified over whether there was a protective effect of high-density lipoprotein cholesterol (HDL-C) or an adverse effect of triglycerides on coronary heart disease (CHD) risk. In a 1991 paper reprinted in the IJE we suggested that the high degree of correlation between the two, together with plausible levels of measurement error, made it unlikely that conventional epidemiological approaches could contribute to causal understanding. The consensus that HDL-C was protective, popularly reified in the notion of ‘good cholesterol’, strengthened over subsequent years. Reviewing the biostatistical and epidemiological literature from before and after 1991 we suggest that within the observational epidemiology pantheon only Mendelian randomization studies—that began to appear at the same time as the initial negative randomized controlled trials—made a meaningful contribution. It is sobering to realize that many issues that appear suitable targets for epidemiological investigation are simply refractory to conventional approaches. The discipline should surely revisit this and other high-profile cases of consequential epidemiological failure—such as that with respect to vitamin E supplementation and CHD risk—rather than pass them over in silence.

Undertreatment of Cardiac Risk Factors in Adolescents with Renal Failure

Cardiovascular disease (CVD) is the most common cause of death in adults with end-stage renal disease and after renal transplantation, and the relative excess of mortality is greatest in the young. The most likely explanation is the dramatic accumulation of both classical and uremic risk factors leading to atherosclerosis, uremic vasculopathy, and uremic cardiomyopathy. Prospective studies have established the significance of classical and uremic risk factors for the occurrence of CVD in the normal population and in the population with chronic renal disease alike. However, whether and to what degree modification of risk factors by therapeutic intervention can lower morbidity and mortality rates is as yet unknown.

Traditional Risk Factors of Acute Coronary Syndrome in Four Different Male Populations – Total Cholesterol Value Does Not Seem To Be Relevant Risk Factor

Cardiovascular diseases are the most common cause of mortality and morbidity in most populations. As the traditional modifiable risk factors (smoking, hypertension, dyslipidemia, diabetes mellitus, and obesity) were defined decades ago, we decided to analyze recent data in patients who survived acute coronary syndrome (ACS). The Czech part of the study included data from 999 males, and compared them with the post-MONICA study (1,259 males, representing general population). The Lithuanian study included 479 male patients and 456 age-matched controls. The Kazakhstan part included 232 patients and 413 controls. In two countries, the most robust ACS risk factor was smoking (OR 3.85 in the Czech study and 5.76 in the Lithuanian study), followed by diabetes (OR 2.26 and 2.07) and hypertension (moderate risk elevation with OR 1.43 and 1.49). These factors did not influence the ACS risk in Kazakhstan. BMI had no significant effect on ACS and plasma cholesterol was surprisingly significantly lower (P<0.001) in patients than in controls in all countries (4.80±1.11 vs. 5.76±1.06 mmol/l in Czechs; 5.32±1.32 vs. 5.71±1.08 mmol/l in Lithuanians; 4.88±1.05 vs. 5.38±1.13 mmol/l in Kazakhs/Russians). Results from our study indicate substantial heterogeneity regarding major CVD risk factors in different populations with the exception of plasma total cholesterol which was inversely associated with ACS risk in all involved groups. These data reflect ethnical and geographical differences as well as changing pattern of cardiovascular risk profiles.

Association between fasting plasma triglycerides, all-cause and cardiovascular mortality in Czech population. Results from the HAPIEE study

Dyslipidemia is the risk factor of cardiovascular disease, but the relationship between the plasma triglyceride (TG) levels and total/cardiovascular mortality has not yet been analyzed in Slavs. The aim of our study was to analyze the association between the fasting TG levels and all-cause/cardiovascular mortality. We have examined 3,143 males and 3,650 females, aged 58.3+/-7.1 years. 729 deaths (274 cardiovascular deaths) have been registered during up to 11.8 years of follow-up. Age-sex adjusted all-cause mortality was higher in individuals with TG values 3.01-4.00 mmol/l (HR 1.37, 95 % CI 1.02-1.83, P=0.035) and over 4.00 mmol/l (HR 1.66, 95 % CI 1.21-2.27, P=0.002) when compared with a reference group (TG 1.41-1.80 mmol/l). Elevated risk remains significant when adjusted for education, marital status and unemployment. When further adjusted for smoking, BMI and dyslipidemia interventions, HR for those in above 4.00 mmol/l group decreased (1.42, P=0.04). The results have been similar when cardiovascular mortality has been examined, however, results reached statistical significance only for the TG over 4.0 mmol/l (P=0.028). Our results confirmed that enhanced plasma levels of plasma triglycerides are dose dependently associated with increased risk of all-cause mortality, however, it seems that individuals with TG values 1.8-3.0 mmol/l are not in higher risk of death.

Birth Month and Cardiovascular Disease Risk Association: Is meaningfulness in the eye of the beholder?

In the modern era, with high-throughput technology and large data size, associational studies are actively being generated. Some have statistical and clinical validity and utility, or at least have biologically plausible relationships, while others may not. Recently, the potential effect of birth month on lifetime disease risks has been studied in a phenome-wide model. We evaluated the associations between birth month and 5 cardiovascular disease-related outcomes in an independent registry of 8,346 patients from Ontario, Canada in 1977-2014. We used descriptive statistics and logistic regression, along with model-fit and discrimination statistics. Hypertension and coronary heart disease (of primary interest) were most prevalent in those who were born in January and April, respectively, as observed in the previous study. Other outcomes showed weak or opposite associations. Ancillary analyses (based on raw blood pressures and subgroup analyses by sex) demonstrated inconsistent patterns and high randomness. Our study was based on a high risk population and could not provide scientific explanations. As scientific values and clinical implications can be different, readers are encouraged to read the original and our papers together for more objective interpretations of the potential impact of birth month on individual and public health as well as toward cumulative/total evidence in general.

Cardiac Damage in Rodents after Exposure to Bis(2-chloroethoxy)methane

We report that an environmental agent, bis(2-chloroethoxy)methane (CEM), caused cardiac toxicity in male and female F344 rats and B6C3F1 mice exposed to the chemical by dermal administration at doses of 0, 50, 100, 200, 400 or 600 mg/kg 5 days a week for up to 14 weeks. Treatment-related deaths occurred in 10/10 male and 10/10 female rats at 600 mg/kg, in 2/10 female rats at 400 mg/kg, and in 3/10 female mice at 600 mg/kg. The heart lesions were more severe in rats than mice, and more severe in females than males. In rats, the no-observed-adverse-effect level (NOAEL) for the heart lesions was 200 mg/kg for males and 100 mg/kg for females; in mice, it was more than 600 mg/kg for males and 200 mg/kg for females. Multifocal, widespread vacuolization of the myocytes comprised the main morphological feature of the lesions, and only in rats was it accompanied by mononuclear cell infiltration, myocytic necrosis and atrial thrombosis. Hearts from male rats were immunohistochemically stained for troponin T (cTnT) protein. Loss of cytoplasmic cTnT correlated with histopathological damage only in the 600 mg/kg animals. CEM is metabolized to thiodiglycolic acid, a chemical that causes mitochondrial dysfunction. It is hypothesized that mitochondrial damage leads to the heart toxicity from bis(2-chloroethoxy)methane.

Heart Disease

There has been a continuing debate among health professionals concerning the appropriate strategy of use for the prevention of ischemic heart disease: a targeted high-risk group strategy or a community strategy. A careful review of the evidence demonstrates that neither approach can be recommended to the exclusion of the other. The results are, however, supportive of the lowering of serum cholesterol in high risk individuals. The inconclusiveness of these studies appears to be related to several problems, which are discussed in the text: statistical powerproblems, characteristics of the interventions, unique design problems associated with prevention trials, and problems related to the choice of modelsfor investigation and intervention. Several suggestionsforfuture research to address each of these problems are made.

The effects of coronary artery calcium screening on behavioral modification, risk perception, and medication adherence among asymptomatic adults: a systematic review

OBJECTIVE

To perform systematic review of the effects of screening for coronary artery calcium (CAC), a subclinical marker of coronary artery disease (CAD), on behavioral or lifestyle modification, risk perception, and medication adherence.

METHODS

We searched through CINAHL, PsychInfo, Web of Science, Cochrane Central Register of Control Trials, and PubMed (Medline) for studies on the effects of CAC screening in asymptomatic individuals across three major domains: behavioral modification, risk perception for CAD, and medication adherence. We extracted data from the retrieved studies, assessed and synthesized the information.

RESULTS

Of the 15 retrieved studies, three were randomized control trials and 12 were observational studies. CAC score was ascertained either as total score, quartiles, or standardized Agatston's ordinal scale. While all the 15 studies involved issues related to behavioral and medication adherence, four involved risk perception of CAD. Although no standardized approach was used in these studies, CAC screening enhanced medication adherence in 13 of the 15 studies, while the others were mixed.

CONCLUSION

CAC screening improved medication adherence and could likely motivated individuals for beneficial behavioral or lifestyle changes to improve CAD. The mixed results suggest the need for further research because screening for subclinical atherosclerosis has significant implications for early detection and prevention of future cardiovascular events by aggressive risk factors modification.

Molecular biology of atherosclerosis

At least 468 individual genes have been manipulated by molecular methods to study their effects on the initiation, promotion, and progression of atherosclerosis. Most clinicians and many investigators, even in related disciplines, find many of these genes and the related pathways entirely foreign. Medical schools generally do not attempt to incorporate the relevant molecular biology into their curriculum. A number of key signaling pathways are highly relevant to atherogenesis and are presented to provide a context for the gene manipulations summarized herein. The pathways include the following: the insulin receptor (and other receptor tyrosine kinases); Ras and MAPK activation; TNF-α and related family members leading to activation of NF-κB; effects of reactive oxygen species (ROS) on signaling; endothelial adaptations to flow including G protein-coupled receptor (GPCR) and integrin-related signaling; activation of endothelial and other cells by modified lipoproteins; purinergic signaling; control of leukocyte adhesion to endothelium, migration, and further activation; foam cell formation; and macrophage and vascular smooth muscle cell signaling related to proliferation, efferocytosis, and apoptosis. This review is intended primarily as an introduction to these key signaling pathways. They have become the focus of modern atherosclerosis research and will undoubtedly provide a rich resource for future innovation toward intervention and prevention of the number one cause of death in the modern world.

Using bioinformatics and systems genetics to dissect HDL-cholesterol genetics in an MRL/MpJ x SM/J intercross

A higher incidence of coronary artery disease is associated with a lower level of HDL-cholesterol. We searched for genetic loci influencing HDL-cholesterol in F2 mice from a cross between MRL/MpJ and SM/J mice. Quantitative trait loci (QTL) mapping revealed one significant HDL QTL (Apoa2 locus), four suggestive QTL on chromosomes 10, 11, 13, and 18 and four additional QTL on chromosomes 1 proximal, 3, 4, and 7 after adjusting HDL for the strong Apoa2 locus. A novel nonsynonymous polymorphism supports Lipg as the QTL gene for the chromosome 18 QTL, and a difference in Abca1 expression in liver tissue supports it as the QTL gene for the chromosome 4 QTL. Using weighted gene co-expression network analysis, we identified a module that after adjustment for Apoa2, correlated with HDL, was genetically determined by a QTL on chromosome 11, and overlapped with the HDL QTL. A combination of bioinformatics tools and systems genetics helped identify several candidate genes for both the chromosome 11 HDL and module QTL based on differential expression between the parental strains, cis regulation of expression, and causality modeling. We conclude that integrating systems genetics to a more-traditional genetics approach improves the power of complex trait gene identification.

Utility of genetic determinants of lipids and cardiovascular events in assessing risk

The prevention of coronary heart disease (CHD) is a major public-health goal, but disease architecture is such that a larger proportion of clinical events occur among the average majority than among the high-risk minority--the prevention paradox. Genetic findings over the past few years have resulted in the reopening of the old debate on whether an individualized or a population-based approach to prevention is preferable. Genetic testing is an attractive tool for CHD risk prediction because it is a low-cost, high-fidelity technology with multiplex capability. Moreover, by contrast with nongenetic markers, genotype is invariant and determined from conception, which eliminates biological variability and makes prediction from early life possible. Mindful of the prevention paradox, this Review examines the potential applications and challenges of using genetic information for predicting CHD, focusing on lipid risk factors and drawing on experience in the evaluation of nongenetic risk factors as screening tests for CHD. Many of the issues we discuss hold true for any late-onset common disease with modifiable risk factors and proven preventative strategies.

Useful tests of usefulness of new risk factors: Tools for assessing reclassification and discrimination

New risk factors for various diseases are suggested at an increasing pace, with promise of clinical usefulness for risk prediction, but almost unvaryingly without formal testing of that property. We propose that a risk factor clinically relevant for risk prediction can be defined as one that correctly alters predicted risk to a clinically relevant extent in persons with a relevant absolute risk, such that it affects clinical decision making. We recommend that investigators who suggest a new risk factor for clinical use investigate if the new risk factor adds capacity to discriminate between persons who will subsequently experience the outcome from those who will not. For that purpose, we provide tools for calculating the net reclassification improvement, NRI, and the integrated discrimination improvement, IDI, using major statistical packages.

Distribution, size, shape, growth potential and extent of abdominal aortic calcified deposits predict mortality in postmenopausal women

Background

Aortic calcification is a major risk factor for death from cardiovascular disease. We investigated the relationship between mortality and the composite markers of number, size, morphology and distribution of calcified plaques in the lumbar aorta.

Methods

308 postmenopausal women aged 48-76 were followed for 8.3 ± 0.3 years, with deaths related to cardiovascular disease, cancer, or other causes being recorded. From lumbar X-rays at baseline the number (NCD), size, morphology and distribution of aortic calcification lesions were scored and combined into one Morphological Atherosclerotic Calcification Distribution (MACD) index. The hazard ratio for mortality was calculated for the MACD and for three other commonly used predictors: the EU SCORE card, the Framingham Coronary Heart Disease Risk Score (Framingham score), and the gold standard Aortic Calcification Severity score (AC24) developed from the Framingham Heart Study cohorts.

Results

All four scoring systems showed increasing age, smoking, and raised triglyceride levels were the main predictors of mortality after adjustment for all other metabolic and physical parameters. The SCORE card and the Framingham score resulted in a mortality hazard ratio increase per standard deviation (HR/SD) of 1.8 (1.51-2.13) and 2.6 (1.87-3.71), respectively. Of the morphological x-ray based measures, NCD revealed a HR/SD >2 adjusted for SCORE/Framingham. The MACD index scoring the distribution, size, morphology and number of lesions revealed the best predictive power for identification of patients at risk of mortality, with a hazard ratio of 15.6 (p < 0.001) for the 10% at greatest risk of death.

Conclusions

This study shows that it is not just the extent of aortic calcification that predicts risk of mortality, but also the distribution, shape and size of calcified lesions. The MACD index may provide a more sensitive predictor of mortality from aortic calcification than the commonly used AC24 and SCORE/Framingham point card systems.

Mediterranean diet and coronary heart disease: is obesity a link? - A systematic review

AIMS

Adherence to a healthy dietary pattern, such as the Mediterranean diet, exerts a beneficial role regarding the development of coronary heart disease. In addition, several studies support the protective role of the Mediterranean diet as far as obesity is concerned. This review, examining results from prospective cohort and cross-sectional studies, as well as clinical trials, aims to clarify whether the beneficial effect of the Mediterranean dietary pattern on coronary heart disease is due to the impact of this diet on weight loss and obesity status or an independent effect.

DATA SYNTHESIS

35 original-research studies that were published in English until 2009, selected through a computer-assisted literature search are discussed, from which 3 were prospective, 11 were cross-sectional studies, and 21 were clinical trials.

CONCLUSION

Although not all studies show a protective effect of the Mediterranean diet on body weight and obesity, the evidence suggests a possible beneficial role of this dietary pattern. Thus the Mediterranean diet protects against the development of coronary heart disease not only because of its beneficial role regarding cardiovascular risk factors, but also due to a possible effect on body weight and obesity.

P value and the theory of hypothesis testing: an explanation for new researchers

In the 1920s, Ronald Fisher developed the theory behind the p value and Jerzy Neyman and Egon Pearson developed the theory of hypothesis testing. These distinct theories have provided researchers important quantitative tools to confirm or refute their hypotheses. The p value is the probability to obtain an effect equal to or more extreme than the one observed presuming the null hypothesis of no effect is true; it gives researchers a measure of the strength of evidence against the null hypothesis. As commonly used, investigators will select a threshold p value below which they will reject the null hypothesis. The theory of hypothesis testing allows researchers to reject a null hypothesis in favor of an alternative hypothesis of some effect. As commonly used, investigators choose Type I error (rejecting the null hypothesis when it is true) and Type II error (accepting the null hypothesis when it is false) levels and determine some critical region. If the test statistic falls into that critical region, the null hypothesis is rejected in favor of the alternative hypothesis. Despite similarities between the two, the p value and the theory of hypothesis testing are different theories that often are misunderstood and confused, leading researchers to improper conclusions. Perhaps the most common misconception is to consider the p value as the probability that the null hypothesis is true rather than the probability of obtaining the difference observed, or one that is more extreme, considering the null is true. Another concern is the risk that an important proportion of statistically significant results are falsely significant. Researchers should have a minimum understanding of these two theories so that they are better able to plan, conduct, interpret, and report scientific experiments.

Evaluating the causal relevance of diverse risk markers: horizontal systematic review

OBJECTIVES

To develop a new methodology to systematically compare evidence across diverse risk markers for coronary heart disease and to compare this evidence with guideline recommendations.

DESIGN

"Horizontal" systematic review incorporating different sources of evidence.

DATA SOURCES

Electronic search of Medline and hand search of guidelines. Study selection Two reviewers independently determined eligibility of studies across three sources of evidence (observational studies, genetic association studies, and randomised controlled trials) related to four risk markers: depression, exercise, C reactive protein, and type 2 diabetes. Data extraction For each risk marker, the largest meta-analyses of observational studies and genetic association studies, and meta-analyses or individual randomised controlled trials were analysed.

RESULTS

Meta-analyses of observational studies reported adjusted relative risks of coronary heart disease for depression of 1.9 (95% confidence interval 1.5 to 2.4), for top compared with bottom fourths of exercise 0.7 (0.5 to 1.0), for top compared with bottom thirds of C reactive protein 1.6 (1.5 to 1.7), and for diabetes in women 3.0 (2.4 to 3.7) and in men 2.0 (1.8 to 2.3). Prespecified study limitations were more common for depression and exercise. Meta-analyses of studies that allowed formal Mendelian randomisation were identified for C reactive protein (and did not support a causal effect), and were lacking for exercise, diabetes, and depression. Randomised controlled trials were not available for depression, exercise, or C reactive protein in relation to incidence of coronary heart disease, but trials in patients with diabetes showed some preventive effect of glucose control on risk of coronary heart disease. None of the four randomised controlled trials of treating depression in patients with coronary heart disease reduced the risk of further coronary events. Comparisons of this horizontal evidence review with two guidelines published in 2007 showed inconsistencies, with depression prioritised more in the guidelines than in our review.

CONCLUSIONS

This horizontal systematic review pinpoints deficiencies and strengths in the evidence for depression, exercise, C reactive protein, and diabetes as unconfounded and unbiased causes of coronary heart disease. This new method could be used to develop a field synopsis and prioritise future development of guidelines and research.

Use of calcium supplements and the risk of coronary heart disease in 52-62-year-old women: The Kuopio Osteoporosis Risk Factor and Prevention Study

BACKGROUND

To analyse prospectively the effect of calcium or calcium+D supplementation on coronary heart disease (CHD) in 52-62-year-old women.

METHODS AND RESULTS

10,555 52-62-year-old women from the population-based Kuopio Osteoporosis Risk Factor and Prevention Study (OSTPRE) who did not have CHD at baseline were followed for nearly 7 years in 1994-2001. Information about use of calcium supplements and health events was obtained from two repeated questionnaires in 1989 and 1994. Information about causes of death during the follow-up was obtained from the Statistics Finland. Information about CHD and other disease morbidity before and during the follow-up was obtained from the Registry of Specially Refunded Drugs of the Finnish Social Insurance Institution (SII). Cox's proportional-hazards models were used to estimate the risk of CHD morbidity related to the use of calcium supplements. At baseline, 2723 women reported current use of calcium or calcium+D supplementation. During the follow-up, CHD was diagnosed in 513 women. Compared to non-users of calcium/calcium+D supplements, the multivariate adjusted hazard ratio (HR) of CHD was 1.24 (95% CI 1.02-1.52) in women who used these supplements. The multivariate adjusted HR for CHD morbidity in postmenopausal women who used calcium/calcium+D supplements was 1.26 (95% CI 1.01-1.57).

CONCLUSIONS

Calcium or calcium+D supplementation appears to increase the risk of CHD among women before old age.

Integrated associations of genotypes with multiple blood biomarkers linked to coronary heart disease risk

Individuals at risk of coronary heart disease (CHD) show multiple correlations across blood biomarkers. Single nucleotide polymorphisms (SNPs) indexing biomarker differences could help distinguish causal from confounded associations because of their random allocation prior to disease. We examined the association of 948 SNPs in 122 candidate genes with 12 CHD-associated phenotypes in 2775 middle aged men (a genic scan). Of these, 140 SNPs indexed differences in HDL- and LDL-cholesterol, triglycerides, C-reactive protein, fibrinogen, factor VII, apolipoproteins AI and B, lipoprotein-associated phospholipase A2, homocysteine or folate, some with large effect sizes and highly significant P-values (e.g. 2.15 standard deviations at P = 9.2 × 10⁻¹⁴⁰ for F7 rs6046 and FVII levels). Top ranking SNPs were then tested for association with additional biomarkers correlated with the index phenotype (phenome scan). Several SNPs (e.g. in APOE, CETP, LPL, APOB and LDLR) influenced multiple phenotypes, while others (e.g. in F7, CRP and FBB) showed restricted association to the index marker. SNPs influencing six blood proteins were used to evaluate the nature of the associations between correlated blood proteins utilizing Mendelian randomization. Multiple SNPs were associated with CHD-related quantitative traits, with some associations restricted to a single marker and others exerting a wider genetic ‘footprint’. SNPs indexing biomarkers provide new tools for investigating biological relationships and causal links with disease. Broader and deeper integrated analyses, linking genomic with transcriptomic, proteomic and metabolomic analysis, as well as clinical events could, in principle, better delineate CHD causing pathways amenable to treatment.

[Metabolic syndrome, its phenotypes, and insulin resistance by HOMA-IR]

The diagnosis of the metabolic syndrome (MS) according to the National Cholesterol Education Program Adult Treatment Panel III does not reflect necessarily the presence of insulin resistance (IR), a potential therapeutical target for type 2 diabetes and cardiovascular disease prevention. Based on previous prevalence data, a cross-sectional study was conducted to determine the HOMA-IR relationship to the MS and some associated abnormalities. HOMA-IR > was higher in individuals with the MS (2.8+/-1.6 vs. 1.8+/-1.4) (p < 0.001). HOMA-IR >or= 2.5 allied good specificity and sensitivity levels for the association of MS and IR. Hyperglycemia, hypertrigliceridemia, and abdominal obesity, the MS components best related to IR, were statistically associated with HOMA-IR > 2.5, but not hypertension neither low HDL-c. The demonstration that some of MS phenotypes or associated abnormalities were more predictive for IR could point out to the possibility of the use of the index as a marker of the presence of IR associated to MS.

C-reactive protein and coronary heart disease: predictive test or therapeutic target?

BACKGROUND

The hepatocyte-derived acute-phase reactant C-reactive protein (CRP) has been the subject of intense research over the last 2 decades for its possible role in the pathogenesis of cardiovascular diseases. This research has spawned interest in the use of the blood concentration of CRP for predicting a first coronary heart disease (CHD) event, which has been made possible with the development of high-sensitivity CRP (hsCRP) assays that can measure the typically low concentrations of CRP that circulate in the absence of an overt infective or inflammatory episode, and as a potential causal factor that might be targeted therapeutically. The research has encompassed observational and genetic epidemiology, basic science studies with cells and tissues, experiments with animal models and humans, and randomized trials (although not of specific CRP-lowering therapies as yet).

CONTENT

We focus on investigations of the potential role of small differences in basal hsCRP concentration seen in healthy individuals and the relationship of such differences to the long-term risk of a first CHD event, rather than on research devoted to the high acute-phase CRP concentrations, which occur after acute atherothrombotic events and can influence the severity of ischemic tissue damage and the subsequent prognosis. We concentrate mainly on research findings at the translational interface and draw on evidence from human observational and genetic epidemiology, as well as from randomized trials.

CONCLUSIONS

As the field matures from one of discovery to an evaluative science, the development of possible clinical applications requires a sharpening of focus on and a critical appraisal of the strengths and deficiencies of the accumulated evidence. Such assessments require attention to both the current state of affairs and the design of future research, so that the existing uncertainties about the utility of CRP in predicting CHD and its role in causing this disease can be resolved.

Establishing evidence for early action: the prevention of reproductive and developmental harm

Developmental and reproductive toxicants that cause serious disease and dysfunction, either lifelong or occurring late in life, can be initiated in the early life stages of human beings and other species. It is often the timing of the dose more than the dose itself that distinguishes harmful from harmless exposures to such toxicants. As much of the harm is irreversible, and sometimes multigenerational, the timing of actions to prevent such harm is also critical. In determining when there is a sufficiency of evidence to justify early prevention of harm, decision-makers need to take account of the implications of multicausality, the methodological biases within environmental sciences, and the need to take precautionary, as well as preventive actions to eliminate or reduce exposures. The widely used Bradford Hill causal 'criteria' are briefly reviewed in light of multicausality. Reaching agreement between stakeholders on a sufficiency of evidence for early action to reduce exposures to toxicants requires the consistent use of transparent definitions of the concepts and terms used to characterize the strength of evidence between causes and effects. Proposals are made to improve those in current use, including a definition of the precautionary principle.

Risk for the development of atherosclerosis in women with a high amount [corrected] of dental plaque and severe gingival inflammation

INTRODUCTION

Chronic infection and inflammation are considered to be risk factors in the development of cardiovascular diseases; the chronic inflammatory and microbial burden caused by the dental plaque in these individuals may predispose them to atherosclerotic process.

AIMS

The aims were to study the involvement of a high level of dental plaque, severe gingival inflammation and periodontitis in the development of early atherosclerotic process in women.

METHODS

Forty-six randomly chosen women with periodontitis and 21 periodontally healthy women were subjected to a comprehensive clinical oral examination, including oral hygiene status and level of gingival inflammation. Atherosclerotic risk factor analysis and carotid ultrasonography were performed. Common carotid artery intima-media thickness (IMT) and lumen diameter were measured and intima-media area (cIMA) was calculated. The following statistical methods were used: analysis of variance, chi-squared tests and multiple logistic regression analysis.

RESULTS

There were highly significant differences between the patients and controls in the amount of dental plaque, gingival inflammation as well as bleeding on probing and pocket depth. The mean values of IMT and cIMA were significantly higher in women with periodontal disease than in controls. Multiple logistic regression analysis identified periodontitis as a principal-independent predictor of both the common carotid artery cIMA and IMT.

CONCLUSIONS

The present results indicate that a high amount of dental plaque, severe gingival inflammation as well as periodontitis seem to be associated with the development of atherosclerotic lesions in women already at its early and subclinical stages.

A personal history of markers of myocyte injury [myocardial infarction]

BACKGROUND

The measurement of proteins in blood to reflect damage to the heart is one of the most successful examples of easily measured biomarkers identifying a serious major health problem. The concept of using a blood test to reflect organ or cell injury requires a substance that is very abundant in the target cell, has a means of reaching blood, a reasonable half-life in blood, and ideally a specific form reflective only of the target cell in tissue. The myocyte's major role is contraction so proteins involved in contraction or the energy to support it should be good candidate markers.

CONCLUSIONS

All the various biomarkers that have been used to detect cardiac damage are involved in contraction or energy metabolism, but the markers evolved empirically starting with transaminases in the 1950s leading to troponins in the 1990s. This history is reviewed with reflections on my experiences with developing assays for CK-MB and Troponin I.

The altered homeostatic theory: A hypothesis proposed to be useful in understanding and preventing ischemic heart disease, hypertension, and diabetes – including reducing the risk of age and atherosclerosis

Evidence will be presented to support the usefulness of the altered homeostatic theory in understanding basic pathogenetic mechanisms of ischemic heart disease (IHD), hypertension, and diabetes, and in improving prevention of these disorders. The theory argues that: IHD, hypertension, and diabetes share the same basic pathogenesis; risk factors favor a sympathetic homeostatic shift; preventative factors favor a parasympathetic homeostatic shift; risk and preventative factors oppose each other through a dynamic risk/prevention balance; and prevention should be based on improving the risk/prevention balance. Prevention based on improving the risk/prevention balance should be more effective, as this method is regarded as reflecting more accurately basic pathogenetic mechanisms. As example, the theory argues that the risk of supposedly nonmodifiable risk factors as age and the risk of relatively nonmodifiable atherosclerosis can be reduced significantly. The possible validity of the altered homeostatic theory was tested by a study based on multiple associations. Findings support a common pathogenesis for IHD, hypertension, and diabetes based on a sympathetic homeostatic shift, and the usefulness of prevention based on improving the risk/prevention balance by using standard pharmaceutical and lifestyle preventative measures. The same set of multiple and diverse risk factors favored IHD, hypertension, and diabetes, and the same set of multiple and diverse pharmaceutical and lifestyle preventative measures prevented these disorders. Also, the same set of preventative agents generally improved cognitive function and bone density, and reduced the incidence of Alzheimer's disease, atrial fibrillation, and cancer. Unexpectedly, evidence was developed that four major attributes of sympathetic activation represent four major risk factors; attributes of sympathetic activation are a tendency toward thrombosis and vasoconstriction, lipidemia, inflammation, and hyperglycemia, and corresponding risk factors are endothelial dysfunction (which expresses thrombosis/vasoconstriction and epitomizes this tendency), dyslipidemia, inflammation, and insulin resistance. These findings, plus other information, provide evidence that dyslipidemia acts mainly as a marker of risk of IHD, rather than being the basic mechanism of this disorder. However, prevention generally is based solely on improvement of dyslipidemia; basing prevention on dyslipidemia relatively underemphasizes the importance of other significant risk factors and, by certifying its validity, discourages alternate pathogenetic approaches. Also, development of myocardial infarction is approached differently. It seems generally accepted that dyslipidemia results rather automatically in infarction through the sequence of atherosclerosis, atherosclerotic complications, and thrombosis. In contrast, distinction is made between development of atherosclerosis and acute induction of infarction--where atherosclerosis is only one of multiple risk factors.

Prognostic immunohistologic markers in human tumors: why are so few used in clinical practice?

Technological advances in gene cloning and genome-wide analyses have greatly increased the number of new tumor markers that can be detected by immunohistologic techniques. While many of these have been evaluated with respect to prognosis, there is a striking discrepancy between the number of markers reported to confer prognostic information and those that are used in clinical practice. We argue that lessons learned from epidemiological studies are applicable to studies of immunohistologic markers; in particular, advances in both fields can be vitiated by non-causal associations. We suggest that the most valuable immunohistologic markers are those that reflect genetic abnormalities, that are linked to the cell of origin, or that reflect tumor infiltrating cells or stromal reactions. It should also be appreciated that a marker that is genuinely predictive of prognosis may nevertheless not find any application in clinical practice if it becomes obsolete through the introduction of newer therapies or because there is no choice of alternative treatment strategies.

Income differences in cardiovascular disease: is the contribution from work similar in prevalence versus mortality outcomes?

The objective of this research is to study the contribution of adverse working conditions to the association between income and cardiovascular disease (CVD), and to analyze differences across prevalence and mortality outcomes. Cross-sectional data from the Swedish Surveys of Living Conditions, 1996-1999 (N = 6,405), and longitudinal registry data for the period 1990-95 (10,916 CVD deaths) were used, including employed wage earners, aged 40-64. Working conditions were assessed through self-reports and imputed from a job exposure matrix, respectively. Multiple logistic and Poisson regressions were applied. There were strong associations between income and CVD. Those in the lowest income quartile had 3.6 (prevalence) and 2.1 (mortality) times higher risk of CVD, compared to those in the highest income quartile (with a gradient for the intermediate groups). In the survey, low job control and physical demands contributed 8-10% to the association between income and CVD prevalence. This contribution was 10% for low job control in the mortality follow-up. A small proportion of the association between income and the prevalence of or mortality from CVD is attributable to working conditions.

Vitronectin in atherosclerotic disease

Atherosclerosis is characterized by the development of an intimal thickening that contains monocytes, T lymphocytes, and smooth muscle cells within an accumulation of lipid and extracellular matrix proteins. Vitronectin is a plasma glycoprotein implicated as a regulator of diverse physiological process, including blood coagulation, fibrinolysis, pericellular proteolysis, complement dependent immune responses, and cell attachment and spreading. Because of its ability to bind platelet glycoproteins and mediate platelet adhesion and aggregation at sites of vascular injury, vitronectin has become an important mediator in the pathogenesis of coronary atherosclerosis.

Pharmacological basis of different targets for the treatment of atherosclerosis

The development of atherosclerotic plaque is a highly regulated and complex process which occurs as a result of structural and functional alterations in endothelial cells, smooth muscle cells (SMCs), monocytes/macrophages, T-lymphocytes and platelets. The plaque formation in the coronary arteries or rupture of the plaque in the peripheral vasculature in latter stages of atherosclerosis triggers the onset of acute ischemic events involving myocardium. Although lipid lowering with statins has been established as an important therapy for the treatment of atherosclerosis, partially beneficial effects of statins beyond decreasing lipid levels has shifted the focus to develop newer drugs that can affect directly the process of atherosclerosis. Blockade of renin angiotensin system, augmentation of nitric oxide availability, reduction of Ca(2+) influx, prevention of oxidative stress as well as attenuation of inflammation, platelet activation and SMC proliferation have been recognized as targets for drug treatment to control the development, progression and management of atherosclerosis. A major challenge for future drug development is to formulate a combination therapy affecting different targets to improve the treatment of atherosclerosis.