Psoas muscle quantified muscle status and long-term mortality after cardiovascular interventions

RESULTS

In the meta-analysis, psoas muscle measurements were significantly associated with mortality among men (p < 0.05), with high heterogeneity in the associations across all cohorts. There was very little difference in the association between PMA and PMD and mortality (HR 0.83, 95% CI 0.69-0.99, p = 0.002; HR 0.85, 95% CI 0.77-0.94, p = 0.041 for one SD increase in PMA and PMD in the random effects model). Combining PMA and PMD into one composite variable by multiplying their values together showed the most robust association in terms of the magnitude of the effect size in men (HR, 0.77; 95% CI 0.73-0.87, p < 0.001). Indexing PMA to body size did not result in any significant differences in this association. Among women, psoas muscle measurements were not associated with long-term mortality in this meta-analysis.

CONCLUSIONS

Different psoas muscle measurements were significantly and very similarly associated with mortality among men but not among women. No single measurement stands out, although combining PMA and PMD seems to be a slightly stronger estimate in terms of effect size and should be considered in further studies.

Influence of early-life body mass index and systolic blood pressure on left ventricle in adulthood - the Cardiovascular Risk in Young Finns Study

BACKGROUND

Increased left ventricular mass (LVM) predicts cardiovascular events and mortality. The objective of this study was to determine whether early-life exposures to body mass index (BMI) and systolic blood pressure (SPB) affects the left ventricular structure in adulthood.

METHODS

We used longitudinal data from a 31-year follow-up to examine the associations between early-life (between ages 6-18) BMI and SPB on LVM in an adult population (N = 1864, aged 34-49). The burden of early-life BMI and SBP was defined as area under the curve.

RESULTS

After accounting for contemporary adult determinants of LVM, early-life BMI burden associated significantly with LVM (3.61 g/SD increase in early-life BMI; [1.94 - 5.28], p < 0.001). Overweight in early-life (age- and sex-specific BMI values corresponding to adult BMI > 25 kg/m²) associated with 4.7% (2.5-6.9%, p < 0.0001) higher LVM regardless of BMI status in adulthood. Overweight in early-life combined with obesity in adulthood (BMI > 30kg/m²) resulted in a 21% (17.3-32.9%, p < 0.0001) increase in LVM. Higher early-life BMI was associated with a risk of developing eccentric hypertrophy. The burden of early-life SPB was not associated with adult LVM or left ventricular remodeling.

CONCLUSIONS

High BMI in early-life confers a sustained effect on LVM and the risk for eccentric hypertrophy independently of adulthood risk factors. KEY MESSAGES Excess in BMI in early-life has an independent effect on LVM and the risk of developing eccentric hypertrophy regardless of overweight status in adulthood. Systolic blood pressure levels in early-life did not have an independent effect on LVM or LV remodeling. The clinical implication of this study is that primary prevention of obesity in early-life may prevent the development of high LVM and eccentric hypertrophy.

Cardiorespiratory fitness and heart rate recovery predict sudden cardiac death independent of ejection fraction

OBJECTIVE

To evaluate whether cardiorespiratory fitness (CRF) and heart rate recovery (HRR) associate with the risk of sudden cardiac death (SCD) independently of left ventricular ejection fraction (LVEF).

METHODS

The Finnish Cardiovascular Study is a prospective clinical study of patients referred to clinical exercise testing in 2001-2008 and follow-up until December 2013. Patients without pacemakers undergoing first maximal or submaximal exercise testing with cycle ergometer were included (n=3776). CRF in metabolic equivalents (METs) was estimated by achieving maximal work level. HRR was defined as the reduction in heart rate 1 min after maximal exertion. Adjudication of SCD was based on death certificates. LVEF was measured for clinical indications in 71.4% of the patients (n=2697).

RESULTS

Population mean age was 55.7 years (SD 13.1; 61% men). 98 SCDs were recorded during a median follow-up of 9.1 years (6.9-10.7). Mean CRF and HRR were 7.7 (SD 2.9) METs and 25 (SD 12) beats/min/min. Both CRF and HRR were associated with the risk of SCD in the entire study population (HR_CRF0.47 (0.37-0.59), p<0.001 and HR_HRR0.57 (0.48-0.67), p<0.001 with HR estimates corresponding to one SD increase in the exposure variables) and with CRF, HRR and LVEF in the same model (HR_CRF0.60 (0.45-0.79), p<0.001, HR_HRR0.65 (0.51-0.82), p<0.001) or adjusting additionally for all significant risk factors for SCD (LVEF, sex, creatinine level, history of myocardial infarction and atrial fibrillation, corrected QT interval) (HR_CRF0.69 (0.52-0.93), p<0.01, HR_HRR0.74 (0.58-0.95) p=0.02).

CONCLUSIONS

CRF and HRR are significantly associated with the risk of SCD regardless of LVEF.

Extensive phenotype data and machine learning in prediction of mortality in acute coronary syndrome - the MADDEC study

Objective: Investigation of the clinical potential of extensive phenotype data and machine learning (ML) in the prediction of mortality in acute coronary syndrome (ACS). Methods: The value of ML and extensive clinical data was analyzed in a retrospective registry study of 9066 consecutive ACS patients (January 2007 to October 2017). Main outcome was six-month mortality. Prediction models were developed using two ML methods, logistic regression and extreme gradient boosting (xgboost). The models were fitted in training set of patients treated in 2007-2014 and 2017 (81%, n = 7344) and validated in a separate validation set of patients treated in 2015-2016 with full GRACE score data available for comparison of model accuracy (19%, n = 1722). Results: Overall, six-month mortality was 7.3% (n = 660). Several variables were found to be significantly associated with six-month mortality by both ML methods. The xgboost scored the best performance: AUC 0.890 (0.864-0.916). The AUC values for logistic regression and GRACE score were 0.867(0.837-0.897) and 0.822 (0.785-0.859), respectively. The AUC value of xgboost was better when compared to logistic regression (p = .012) and GRACE score (p < .00001). Conclusions: The use of extensive phenotype data and novel machine learning improves prediction of mortality in ACS over traditional GRACE score. KEY MESSAGES The collection of extensive cardiovascular phenotype data from electronic health records as well as from data recorded by physicians can be used highly effectively in prediction of mortality after acute coronary syndrome. Supervised machine learning methods such as logistic regression and extreme gradient boosting using extensive phenotype data significantly outperform conventional risk assessment by the current golden standard GRACE score. Integration of electronic health records and the use of supervised machine learning methods can be easily applied in a single centre level to model the risk of mortality.

Thyroid-stimulating hormone and risk of sudden cardiac death, total mortality and cardiovascular morbidity

BACKGROUND

Previous data on the association of thyroid function with total mortality, cardiovascular disease (CVD) outcomes and sudden cardiac death (SCD) are conflicting or limited. We investigated associations of thyroid-stimulating hormone (TSH) with these outcomes in a nationwide population-based prospective cohort study.

METHODS

We examined 5211 participants representative of the Finnish population aged ≥30 years in 2000-2001 and followed them for a median of 13.2 years. Using Cox proportional hazards regression models adjusted for baseline age, gender, smoking, diabetes, systolic blood pressure and total and high-density lipoprotein cholesterol, we assessed the associations of continuous baseline TSH and TSH categories (low [<0.4 mU/L], reference range [0.4-3.4 mU/L] and high [>3.4 mU/L]) with incident total mortality, SCD, coronary heart disease events, stroke, CVD, major adverse cardiac events and atrial fibrillation.

RESULTS

High TSH at baseline was related to a greater risk of total mortality (HR 1.34, 95% CI 1.02-1.76) and SCD (HR 2.28, 95% CI 1.13-4.60) compared with TSH within the reference range. High TSH was not associated with the other outcomes (P ≥ .51), whereas low TSH was not associated with any of the outcomes (P ≥ .09). TSH at baseline over the full range did not have a linear relation with any of the outcomes (P ≥ .17). TSH showed a U-shaped association with total mortality after a restricted cubic spline transformation (P = .01).

CONCLUSIONS

Thyroid function abnormalities could be linked with higher risks of total mortality and SCD. Large-scale randomized studies are needed for evidence-based recommendations regarding treatment of mild thyroid failure.

Aortic sinus diameter in middle age is associated with body size in young adulthood

OBJECTIVE

Aortic sinus dilatation can lead to aortic valve regurgitation or even aortic dissection. Our objective was to examine the association between body surface area (BSA) measures from childhood to middle age and aortic sinus diameter in middle age. Understanding the relation of these two clarifies how aortic size is normally determined.

METHODS

Cardiovascular Risk in Young Finns Study is a longitudinal study with follow-up of over 31 years (1980-2011). The study comprises information of body composition from multiple time points of 1950 subjects with cardiac ultrasound measurements made in 2011. The association between BSA in different ages and aortic sinus diameter in middle age was analysed by linear regression modelling adjusted with age, sex and diastolic blood pressure. Missing BSA values were derived for each life year (ages 3-33 years) from subject-specific curves for body weight and height estimated from longitudinal measurements using mixed model regression splines.

RESULTS

BSA estimates in early 20s are most strongly associated with aortic sinus diameter in middle age. Top association was observed at age 23 years with one SD increase in estimated BSA corresponding to 1.04 mm (0.87-1.21 mm) increase in aortic diameter. Increase in body weight beyond early 20s does not associate with aortic sinus diameter, and the association between middle age BSA and aortic size is substantially weaker (0.74 mm increase (0.58-0.89 mm)). These results were confirmed in a subpopulation using only measured data.

CONCLUSION

The association between aortic sinus diameter and BSA is stronger when considering BSA in young adulthood compared with BSA in middle age.

Apolipoproteins and HDL cholesterol do not associate with the risk of future dementia and Alzheimer's disease: the National Finnish population study (FINRISK)

Data on associations of apolipoproteins A-I and B (apo A-I, apo B) and HDL cholesterol (HDL-C) with dementia and Alzheimer's disease (AD) are conflicting. Our aim was to examine, whether apo B, apoA-I, their ratio, or HDL-C are significant, independent predictors of incident dementia and AD in the general population free of dementia at baseline. We analyzed the results from two Finnish prospective population-based cohort studies in a total of 13,275 subjects aged 25 to 74 years with mainly Caucasian ethnicity. The follow-up time for both cohorts was 10 years. We used Cox proportional hazards regression to evaluate hazard ratios (HR) for incident dementia (including AD) (n = 220) and for AD (n = 154). Cumulative incidence function (CIF) analysis was also performed to adjust the results for competing risks of death. Adjusted for multiple dementia and AD risk factors, log-transformed apo A-I, log HDL-C, log apo B, and log apo B/A-I ratio were not associated with incident dementia or AD. HDL-C was inversely associated with AD risk when adjusted for competing risks but no other statistically significant associations were observed in the CIF analyses. Apo A-I, HDL-C, apo B, or apo B/A-I ratio were not associated with future dementia or AD. HDL-C was inversely associated with incident AD risk when adjusted for competing risks of death, but the finding is unlikely to be of clinical relevance. Our study does not support the use of these risk markers to predict incident dementia or AD.

Associations of functional alanine-glyoxylate aminotransferase 2 gene variants with atrial fibrillation and ischemic stroke

Asymmetric and symmetric dimethylarginines (ADMA and SDMA) impair nitric oxide bioavailability and have been implicated in the pathogenesis of atrial fibrillation (AF). Alanine–glyoxylate aminotransferase 2 (AGXT2) is the only enzyme capable of metabolizing both of the dimethylarginines. We hypothesized that two functional AGXT2 missense variants (rs37369, V140I; rs16899974, V498L) are associated with AF and its cardioembolic complications. Association analyses were conducted using 1,834 individulas with AF and 7,159 unaffected individuals from two coronary angiography cohorts and a cohort comprising patients undergoing clinical exercise testing. In coronary angiography patients without structural heart disease, the minor A allele of rs16899974 was associated with any AF (OR = 2.07, 95% CI 1.59-2.68), and with paroxysmal AF (OR = 1.98, 95% CI 1.44–2.74) and chronic AF (OR = 2.03, 95% CI 1.35–3.06) separately. We could not replicate the association with AF in the other two cohorts. However, the A allele of rs16899974 was nominally associated with ischemic stroke risk in the meta-analysis of WTCCC2 ischemic stroke cohorts (3,548 cases, 5,972 controls) and with earlier onset of first-ever ischemic stroke (360 cases) in the cohort of clinical exercise test patients. In conclusion, AGXT2 variations may be involved in the pathogenesis of AF and its age-related thromboembolic complications.

The prevalence of abdominal aortic aneurysm is consistently high among patients with coronary artery disease

OBJECTIVE

Emerging evidence suggests high prevalence of abdominal aortic aneurysm (AAA) among patients with coronary disease. Accurate characterization of the association between coronary disease and AAA and of the actual prevalence of AAA among patients with angiography-verified coronary artery disease (CAD) is needed to evaluate the possible benefits of systematic screening for AAA.

METHODS

We searched for studies that reported the association between AAA and CAD or coronary heart disease (CHD; wider phenotype definition) in the general population (randomized controlled trials, prospective population cohorts) and those that reported the prevalence of AAA among patients with angiography-verified CAD through PubMed, Embase, and reference lists for the period between 1980 and 2014. Random-effects models were applied because of the high heterogeneity between included studies.

RESULTS

Among the general population, 23 studies reported the association between CHD and the occurrence of subclinical AAA (positive ultrasound screening; meta-analyzed odds ratio of 2.38 with 95% confidence interval [CI] of 1.78-3.19; P = 4.1 × 10(-9)). According to four prospective studies, CHD is a strong predictor of future AAA events (fatal and nonfatal; meta-analyzed hazard ratio of 3.49 with 95% CI of 2.56-4.76; P = 2.4 × 10(-15)). Altogether, 10 studies reported the prevalence of AAA among patients with angiography-verified CAD or undergoing coronary artery bypass grafting. Among men, meta-analyzed prevalence was 9.5% (95% CI, 7.6%-11.7%). Among men undergoing coronary artery bypass grafting or with three-vessel disease, the prevalence was 11.4% (95% CI, 9.1%-13.9%). Among women, the prevalence was low (0.35%).

CONCLUSIONS

The risk of subclinical AAA and future AAA events is high among patients with coronary disease. Screening for AAA among CAD patients by cardiologists would be easy and inexpensive, with possible benefits to survival and risk evaluation.

Significant interactions between traditional risk factors affect cardiovascular risk prediction in healthy general population

AIMS

The aim was to carry out a systematic screening of interactions between the traditional risk factors and to evaluate which interactions are truly relevant for estimation of cardiovascular disease (CVD) risk.

METHODS

Cox regression was used in a meta-analysis of five independent, population-based health examination surveys (the National FINRISK Study). End-points were 10-year incidence of coronary heart disease (CHD), ischemic stroke (IS), and CVD in a population free of cardiovascular disease (n = 35,460).

RESULTS

In addition to expected age interactions, systolic blood pressure was found to be a markedly stronger risk factor for CVD (and for CHD) among subjects with normal BMI (BMI < 25: HR 1.42 [1.30-1.55] for one SD increase in systolic blood pressure) when compared to obese subjects (BMI > 30: HR 1.10 [1.01-1.19]) (P < 0.001 for interaction) and among subjects with highest high-density lipoprotein (HDL) (33% tertile: HR 1.43 [1.29-1.58]) when compared to subjects with low HDL (lowest 33% tertile: HR 1.20 [1.13-1.28]) (P < 0.001 for interaction). Interactions improved risk prediction of CVD (cross-validated continuous net reclassification improvement [NRI] 49.4% with 95% CI 44.7%-54.1%, P < 0.0001 and clinical NRI 4.7%, with 95% CI 2.8%-6.5%, P < 0.0001). The C-statistic improved from 0.8438 to 0.8455 (P = 0.010). No significant interaction was associated with the risk of IS.

CONCLUSIONS

There are significant effect modifications between major risk factors, and accounting for them leads to significantly more accurate estimation of cardiovascular risk.

Genome-wide association study on dimethylarginines reveals novel AGXT2 variants associated with heart rate variability but not with overall mortality

AIMS

The purpose of this study was to identify novel genetic variants influencing circulating asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) levels and to evaluate whether they have a prognostic value on cardiovascular mortality.

METHODS AND RESULTS

We conducted a genome-wide association study on the methylarginine traits and investigated the predictive value of the new discovered variants on mortality. Our meta-analyses replicated the previously known locus for ADMA levels in DDAH1 (rs997251; P = 1.4 × 10(-40)), identified two non-synomyous polymorphisms for SDMA levels in AGXT2 (rs37369; P = 1.4 × 10(-40) and rs16899974; P = 1.5 × 10(-38)) and one in SLC25A45 (rs34400381; P = 2.5 × 10(-10)). We also fine-mapped the AGXT2 locus for further independent association signals. The two non-synonymous AGXT2 variants independently associated with SDMA levels were also significantly related with short-term heart rate variability (HRV) indices in young adults. The major allele (C) of the novel non-synonymous rs16899974 (V498L) variant associated with decreased SDMA levels and an increase in the ratio between the low- and high-frequency spectral components of HRV (P = 0.00047). Furthermore, the SDMA decreasing allele (G) of the non-synomyous SLC25A45 (R285C) variant was associated with a lower resting mean heart rate during the HRV measurements (P = 0.0046), but not with the HRV indices. None of the studied genome-wide significant variants had any major effect on cardiovascular or total mortality in patients referred for coronary angiography.

CONCLUSIONS

AGXT2 has an important role in SDMA metabolism in humans. AGXT2 may additionally have an unanticipated role in the autonomic nervous system regulation of cardiac function.

Genome-wide association study pinpoints a new functional apolipoprotein B variant influencing oxidized low-density lipoprotein levels but not cardiovascular events: AtheroRemo Consortium

BACKGROUND

Oxidized low-density lipoprotein may be a key factor in the development of atherosclerosis. We performed a genome-wide association study on oxidized low-density lipoprotein and tested the impact of associated single-nucleotide polymorphisms (SNPs) on the risk factors of atherosclerosis and cardiovascular events.

METHODS AND RESULTS

A discovery genome-wide association study was performed on a population of young healthy white individuals (N=2080), and the SNPs associated with a P<5×10(-8) were replicated in 2 independent samples (A: N=2912; B: N=1326). Associations with cardiovascular endpoints were also assessed with 2 additional clinical cohorts (C: N=1118; and D: N=808). We found 328 SNPs associated with oxidized low-density lipoprotein. The genetic variant rs676210 (Pro2739Leu) in apolipoprotein B was the proxy SNP behind all associations (P=4.3×10(-136), effect size=13.2 U/L per allele). This association was replicated in the 2 independent samples (A and B, P=2.5×10(-47) and 1.1×10(-11), effect sizes=10.3 U/L and 7.8 U/L, respectively). In the meta-analyses of cohorts A, C, and D (excluding cohort B without angiographic data), the top SNP did not associate significantly with the age of onset of angiographically verified coronary artery disease (hazard ratio=1.00 [0.94-1.06] per allele), 3-vessel coronary artery disease (hazard ratio=1.03 [0.94-1.13]), or myocardial infarction (hazard ratio=1.04 [0.96-1.12]).

CONCLUSIONS

This novel genetic marker is an important factor regulating oxidized low-density lipoprotein levels but not a major genetic factor for the studied cardiovascular endpoints.

IL-18 gene polymorphism, cardiovascular mortality and coronary artery disease

BACKGROUND

Interleukin 18(IL-18) is a pro-atherosclerotic cytokine. Elevated IL-18 levels and the genetic variation of the IL-18 have been previously linked with acute coronary events and cardiovascular mortality among patients with coronary artery disease (CAD). We studied the possible association between the IL-18 gene polymorphism and cardiovascular mortality during follow-up among Finnish patients who had undergone a clinical exercise stress test, in addition to the possible effect on the expression of angiography-verified CAD.

MATERIALS AND METHODS

A total of 2152 patients of the Finnish Cardiovascular Study (cohort study) were followed up for 6·3years and cardiovascular mortality was recorded. Angiography was performed on 461 patients. Genotyping of five common single nucleotide polymorphisms (SNPs) of the IL-18 gene was performed using the 5'nuclease assay for allelic discrimination with the ABI Prism 7900HT Sequence Detection System.

RESULTS

Among the study population, IL-18 gene polymorphism did not associate with cardiovascular mortality. According to adjusted binary regression analysis, the male carriers of one major haplotype (the only ones carrying the t allele of the +127 C/t SNP) had a lower occurrence rate for significant CAD defined as > 50% stenosis in at least one of the main branches of the coronary arteries (OR 0·495, 95% CI 0·862-0·284, P=0·041). No associations were observed among women. The sex-by-genotype interaction was significant (P=0·033).

CONCLUSIONS

The IL-18 gene was not found to associate significantly with mortality. Among patients who had coronary angiography, one major haplotype of the IL-18 gene has a gender-dependent different impact on the expression of CAD.

Genetic variants and their interactions in the prediction of increased pre-clinical carotid atherosclerosis: the cardiovascular risk in young Finns study

The relative contribution of genetic risk factors to the progression of subclinical atherosclerosis is poorly understood. It is likely that multiple variants are implicated in the development of atherosclerosis, but the subtle genotypic and phenotypic differences are beyond the reach of the conventional case-control designs and the statistical significance testing procedures being used in most association studies. Our objective here was to investigate whether an alternative approach--in which common disorders are treated as quantitative phenotypes that are continuously distributed over a population--can reveal predictive insights into the early atherosclerosis, as assessed using ultrasound imaging-based quantitative measurement of carotid artery intima-media thickness (IMT). Using our population-based follow-up study of atherosclerosis precursors as a basis for sampling subjects with gradually increasing IMT levels, we searched for such subsets of genetic variants and their interactions that are the most predictive of the various risk classes, rather than using exclusively those variants meeting a stringent level of statistical significance. The area under the receiver operating characteristic curve (AUC) was used to evaluate the predictive value of the variants, and cross-validation was used to assess how well the predictive models will generalize to other subsets of subjects. By means of our predictive modeling framework with machine learning-based SNP selection, we could improve the prediction of the extreme classes of atherosclerosis risk and progression over a 6-year period (average AUC 0.844 and 0.761), compared to that of using conventional cardiovascular risk factors alone (average AUC 0.741 and 0.629), or when combined with the statistically significant variants (average AUC 0.762 and 0.651). The predictive accuracy remained relatively high in an independent validation set of subjects (average decrease of 0.043). These results demonstrate that the modeling framework can utilize the "gray zone" of genetic variation in the classification of subjects with different degrees of risk of developing atherosclerosis.

Coronary artery disease-related genetic variant on chromosome 10q11 is associated with carotid intima-media thickness and atherosclerosis

OBJECTIVE

To investigate whether chromosome 10q11.21 influences common carotid intima-media thickness (IMT) and atherosclerosis and whether it is associated with stromal cell-derived factor-1α (SDF-1α) plasma levels.

METHODS AND RESULTS

Variation on chromosome 10q11.21 has been consistently associated with coronary artery disease. The genetic variant lies upstream of the gene encoding SDF-1α. We genotyped 3 population cohorts (Bruneck [age range, 45 to 94 years; 50.0% men; n=738], Health2000 [age range, 46 to 76 years; 55.4% men; n=1237], and essential hypertension in families collected in the region of Oxford [HTO] [age range, 19 to 88 years; 47.9% men; n=770]) for single-nucleotide polymorphism rs501120 at the 10q11.21 locus and conducted a meta-analysis in these cohorts to ascertain a relationship between the polymorphism and carotid IMT. The analysis showed that individuals with the T/T genotype had a significantly higher carotid IMT than individuals with the C/T or C/C genotype (pooled weighted mean difference, 23 μm [95% CI, 9 to 37 μm], P=0.0014 under a fixed-effects model; and 23 μm [95% CI, 6 to 41 μm], P=0.009 under a random-effects model). In the Bruneck cohort, in which data for carotid atherosclerosis and plasma SDF-1α levels were available, we observed an association of the T/T genotype with a higher burden of atherosclerosis and increased susceptibility to the development of atherosclerosis during a 5-year follow-up (multivariable odds ratio, 1.73 [95% CI, 1.18 to 2.52]; P=0.005 for the recessive model) and an association between the T/T genotype and lower SDF-1α levels (2.62 ng/mL for T/T versus 2.74 ng/mL for C/C or C/T; P=0.023).

CONCLUSIONS

The coronary heart disease-related variant at the 10q11.21 locus is associated with carotid IMT and atherosclerosis.

Interleukin-18 gene polymorphism and markers of subclinical atherosclerosis. The Cardiovascular Risk in Young Finns Study

BACKGROUND AND AIM

Interleukin-18 (IL-18) is a pro-atherosclerotic cytokine. We wanted to evaluate whether IL-18 gene polymorphism associates independently of risk factors, with early subclinical markers of atherosclerosis (intima-media thickness (IMT), coronary artery compliance (CAC), and flow-mediated dilatation (FMD)) in a population of young healthy Caucasian adults.

METHODS

This study was based on the on-going Cardiovascular Risk in Young Finns Study consisting of 2260 young adults, mean age being 31.7 (range 24-39 years) (1247 women and 1013 men).

RESULTS

Five studied tagSNPs formed six major haplotypes, which accounted for 99.9% of all variation of the IL-18 gene. According to adjusted analysis of variance, the IL-18 gene polymorphism did not associate with subclinical atherosclerosis in the whole study population. However, one major haplotype associated differently among men and women with IMT (P = 0.011). Male carriers of a major CCTgT haplotype (n = 441) seemed to have a lower IMT when compared to the non-carriers (-0.016 mm, 95% confidence interval (CI) -0.028 to -0.004, P = 0.014). Among women no significant associations were observed.

CONCLUSIONS

Among all study subjects, the polymorphism of the IL-18 gene is not associated with subclinical markers of atherosclerosis. However, among men one major IL-18 haplotype seemed to associate with substantially lower IMT values.

ADAM8 and its single nucleotide polymorphism 2662 T/G are associated with advanced atherosclerosis and fatal myocardial infarction: Tampere vascular study

OBJECTIVE

Previously, we scanned all 23,000 human genes for differential expression between normal and atherosclerotic tissues and found the involvement of ADAM8.

METHODS

We investigated the expression of ADAM8 mRNA and protein level in human atherosclerotic tissues and non-atherosclerotic internal thoracic arteries as well as the association of ADAM8 2662 T/G single nucleotide polymorphism (SNP) with the extent of coronary atherosclerosis and with the risk of fatal myocardial infarction.

RESULTS

ADAM8 mRNA was up-regulated in carotid, aortic, and femoral atherosclerotic plaques (n=24) when compared with non-atherosclerotic arteries. ADAM8 protein expression was increased in advanced atherosclerotic plaques as compared to control vessels wherein it was localized to macrophages and smooth muscle cells The G allele carriers of the ADAM8 2662 T/G SNP had significantly larger areas of fibrotic, calcified, and complicated plaques in coronary arteries (P=0.027, P=0.011, and P=0.011, respectively) and significantly higher occurrence of myocardial infarction (MI) (P=0.004) and fatal pre-hospital MI (P=0.003) than did the TT homozygotes.

CONCLUSION

ADAM8 is a promising candidate to be involved in atherosclerosis, and its 2662 T/G allelic variant significantly associates with advanced atherosclerotic lesion areas and MI.

Toll-like receptor 4 gene (Asp299Gly) polymorphism associates with carotid artery elasticity. The cardiovascular risk in young Finns study

OBJECTIVE

Early subclinical markers of atherosclerosis, such as carotid artery intima media thickness (IMT) and elasticity predict future coronary events. The G allele of the Toll-like receptor 4 (TLR-4) gene Asp299Gly polymorphism has been previously associated with decreased development of atherosclerosis and with lower risk of myocardial infractions. We wanted to examine the association of this polymorphism with carotid IMT and compliance in a population of young Finnish Caucasian adults.

METHODS

Carotid artery IMT and elasticity indices of 2201 study subjects who participated in a randomized multicenter study (cardiovascular risk in young Finns study) were measured with ultrasound. The genotyping was performed using the TaqMan 5'-nuclease assay.

RESULTS

According to multivariate linear regression analysis adjusted with potential confounders, the G allele carriers had significantly higher carotid arterial compliance, measured in increase of luminal diameter percentage in response to blood pressure rise of 10 mmHg, than did the AA homozygotes (beta=0.099 with 95% CI 0.029-0.169 and p=0.006). The difference between AA homozygotes and GG homozygotes was even more pronounced (beta=0.382 with 95% CI 0.119-0.644 and p=0.004). Variation in the TLR-4 genotype was not related with IMT. The results of the two independent study cohorts of Eastern and Western Finland were in accordance with the results of the whole combined study population.

CONCLUSION

The G allele of the TLR-4 gene Asp299Gly polymorphism is associated with increased carotid artery compliance in young adults. This beneficial effect of the G allele may reduce the risk of future cardiovascular events.

Interleukin-18 promoter polymorphism associates with the occurrence of sudden cardiac death among Caucasian males: the Helsinki Sudden Death Study

OBJECTIVE

The increased plasma concentrations of pro-atherogenic and cardiomyocyte hypertrophic cytokine interleukin 18 (IL-18) predict mortality in patients with coronary heart disease (CHD) in addition to predicting the outcome of heart failure. The IL-18 gene has a functional -137G/C polymorphism (rs187238) in the promoter region. The C allele carriage is associated with attenuated IL-18 production. The effect of IL-18 genotype on SCD is unknown. We studied the association of the IL-18 gene -137G/C polymorphism with the occurrence of sudden cardiac death (SCD).

METHODS

Using the TaqMan 5' nuclease assay, we genotyped two independent consecutive and prospective autopsy series which were included in the Helsinki Sudden Death Study.

RESULTS

Of the 663 men, 359 (54.1%) had the wild-type GG-genotype, 261 (39.4%) were heterozygotes (CG) and 43 (6.5%) were CC homozygotes. Compared to the GG homozygotes, the C allele carriers (i.e. subjects having CC or CG genotypes) had a lower adjusted risk for SCD from any cause (odds ratio [OR] 0.49; 95% confidence interval [CI], 0.31-0.77, p=0.002), for SCD due to CHD (OR 0.51; 95% CI, 0.32-0.82, p=0.005), and for SCD caused by non-coronary heart diseases (OR 0.34; 95% CI 0.13-0.90, p=0.030).

CONCLUSION

IL-18 promoter -137G/C polymorphism, which regulates the expression of IL-18, is an important predictor of SCD from any cause as well as SCD in patients with and without underlying CHD.

Magnetic resonance angiographic screening for asymptomatic intracranial aneurysms: the problem of false negatives: technical case report

To emphasize the limitations of magnetic resonance angiographic screening for intracranial aneurysms, we present the case of a patient with a false-negative screening result, unfortunately advancing to rupture of the aneurysm. An asymptomatic woman underwent magnetic resonance angiographic screening in an investigational setting. Three years later, she had an onset of sudden headache, after which her condition rapidly deteriorated. Severe subarachnoid hemorrhage and an intracerebral hematoma were diagnosed. Conventional angiography detected a small ruptured middle cerebral artery trifurcation aneurysm and two very small aneurysms. There are still limitations in the ability of magnetic resonance angiography to detect small or very small aneurysms. Even small-probability findings should always be confirmed or excluded by conventional angiography.

Intracranial aneurysms: MR angiographic screening in 400 asymptomatic individuals with increased familial risk

PURPOSE

To evaluate the accuracy and limitations of magnetic resonance (MR) angiographic screening for incidental intracranial aneurysms (IAs) in healthy individuals with a family history of IA.

MATERIALS AND METHODS

Four hundred asymptomatic individuals in 68 families with a history of aneurysmal subarachnoid hemorrhage underwent MR angiography. Six families also had a history of polycystic kidney disease. A multislab, three-dimensional, time-of-flight sequence was used. Conventional angiography was performed to confirm positive MR angiographic findings.

RESULTS

IAs were detected with MR angiography in 37 individuals, 32 of whom underwent conventional angiography. Intraobserver consistency was excellent (kappa = 0.96), and interobserver reproducibility was good to excellent (kappa = 0.59-0.82). Both techniques showed similar results in the evaluation of size, localization, and orientation of aneurysms and visibility of the aneurysm neck.

CONCLUSION

MR angiography is an accurate and feasible method of noninvasive screening for IAs in individuals at high risk. Conventional angiography is still necessary before operative treatment.

Contribution of non-neurologic disturbances in acute physiology to the prediction of intensive care outcome after head injury or non-traumatic intracranial haemorrhage

OBJECTIVE

To study the additional contribution of non-neurologic disturbances in acute physiology and chronic health to the prediction of intensive care outcome in patients with head injury or non-traumatic intracranial haemorrhage.

DESIGN

A nationwide study in Finland with prospectively collected data on all adult patients admitted to intensive care after head trauma or non-traumatic intracranial haemorrhage during a 14-month period. Two-thirds of the patients were randomly selected to derive predictive models, and the remaining one third constituted the validation sample.

SETTING

A total of 25 medical and surgical ICUs in Finland (13 in tertiary referral centers).

PATIENTS

901 consecutive adult patients with head injury or non-traumatic intracranial haemorrhage.

MEASUREMENTS AND RESULTS

Variables of the APACHE II including Glasgow Coma Score were collected at the time of ICU admission. Two predictive models were created to explain hospital mortality. The addition of variables describing acute physiology to a predictive model consisting of Glasgow Coma Score, age, diagnosis of head injury and the type of ICU admission did not increase its performance in discriminating between survivors and nonsurvivors, but the calibration accuracy of the predictive model especially at the high ranges of risk was improved.

CONCLUSIONS

The non-neurologic disturbances in acute physiology have prognostic significance in the prediction of intensive care outcome in patients with head injury or non-traumatic intracerebral haemorrhage. The created predictive model may supplement clinical judgement of this patient group.

Quantitative metabolite patterns of human brain tumors: detection by 1H NMR spectroscopy in vivo and in vitro

OBJECTIVE

The aim of the present study was to investigate quantitative metabolite patterns in human brain tumors by 1H nuclear MR spectroscopy (1H MRS).

MATERIALS AND METHODS

Single voxel 1H MRS was used in studying metabolites in 23 primary brain tumors in vivo. The T2 relaxation times and saturation factors were determined for N-acetylaspartate (NAA), total creatine (Cr), choline-containing compounds (Cho), and water, which was used as an internal standard in computations of metabolite concentrations in vivo. Metabolites in biopsy specimens from 75 tumors were quantified by means of 1H MRS in vitro.

RESULTS

The NAA concentrations were lower in brain tumors than in normal tissue in vitro and in vivo, irrespective of the histological type. The NAA was some threefold higher in vivo than in vitro, which could be due to partial volume effect and/or contributions from other metabolites to the peak at 2.02 ppm in vivo. Ratios of Cho to Cr concentrations were elevated in tumors relative to normal brain in vivo. Absolute Cho was some 50% higher in both benign astrocytomas and oligodendrogliomas in vivo than in normal brain. However, Cho concentration in vitro was significantly higher only in pituitary adenomas than in healthy white matter. Total creatine was approximately 50% lower in malignant astrocytomas and meningiomas than in normal brain.

CONCLUSION

It is concluded that absolute concentrations of metabolites in vivo yield a different picture of tumor metabolites than that derived from uncorrected metabolite ratios.

Early surgery for ruptured vertebrobasilar aneurysms

The authors present a series of 1767 patients with aneurysms of the vertebrobasilar circulation, most of whom were operated on 14 days or more following their last subarachnoid hemorrhage (SAH). Since 1970, 206 patients with vertebrobasilar aneurysms have been surgically treated within 7 days after their last SAH (day of SAH = Day 0). Of patients with a good preoperative grade (Botterell Grade 1 or 2), a good or excellent outcome was obtained in 80% during the first postsurgical month, irrespective of the timing of surgery. All except one of the Grade 5 patients died, and 70% of the Grade 4 patients were significantly disabled or dead. The overall operative mortality rate was the same whether surgery took place in the 1st week after SAH or was delayed. The frequency of rupture of the aneurysm during early surgery was not higher than during late surgery. Thirteen percent of patients developed a delayed ischemic neurological deficit as a consequence of reactive arterial narrowing (vasospasm). The authors recommend early surgery for patients with a good preoperative grade, whose aneurysm does not present a particular technical difficulty because of size, configuration, or location, and occasionally in patients whose lives appear to be in jeopardy because of recurrent hemorrhage.

De novo aneurysms: special multiple intracranial aneurysms

Very few patients develop completely new intracranial aneurysms during long-term follow-up after successfully treated subarachnoid hemorrhages. Aneurysms appearing after therapeutic ligation of proximal major vessels or failed surgery and the growth of previously noticed infundibular widenings or small aneurysms must be excluded to find true de novo aneurysms. Twenty-nine true cases of de novo aneurysms were reported in the literature, and 13 additional cases of our own are described. The incidence of de novo aneurysm formation and rupture is 63 per 100,000 per year in patients known to have a subarachnoid hemorrhage. Young patients could benefit from long-term neuroradiological follow-up.

One-year outcome in early aneurysm surgery: prediction of outcome

Predictors of one-year outcome were studied in patients treated for ruptured intracranial aneurysm. A total of 929 patients, who were treated conservatively or surgically, and 839 patients as a part of this population who were surgically treated, were randomly divided into two groups in order to create predictive models by logistic regression and to validate them. The models were derived from two-thirds of these two patient groups and the remaining one-thirds were used for validation. The pre-operative variables of both conservatively and surgically treated patients were studied by Model A. The pre-operative Grade (Hunt and Hess), age, and the presence of vasospasm on angiography were the three most important predictors of the one-year outcome (Glasgow Outcome Scale 1-2/3-5). Model B consisted of pre- and per-operative, and Model C pre-, per-, and post-operative variables collected from the surgically treated group. The pre-operative Grade, ligation of a major vessel and age were the three most powerful determinants of outcome in Model B. In Model C high Grade, post-operative CT-hypodensities and ligation of a major vessel were most closely associated with poor outcome. Model A, based on pre-operative data, most accurately predicted good outcome. All the 59 patients in the validation sample (n = 310) who were predicted to have a less than 5% probability of poor outcome had a favourable outcome (positive and negative predictive value 100%). Model C determined that 22 of 280 patients would have a more than 80% probability of poor outcome.(ABSTRACT TRUNCATED AT 250 WORDS)