Atrial fibrillation and 13-year risk of CVD mortality in Russian population cohort

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): The study was supported by RFBR #20-313-90015, RAS # АААА-А17-117112850280-2

Introduction

Given the worldwide increase in life expectancy, ageing-related conditions are becoming increasingly important. Atrial fibrillation (AF) is the most common arrhythmia and a serious predictor of the progression of heart failure and thromboembolic events (largely, stroke). Thus, the study of AF impact on cardiovascular (CVD) mortality is of particular relevance.

Objectives

We aimed to analyze the impact of AF on the 13-year risk of CVD mortality in the Russian population sample of elderly age.

Methods

A random population sample (n=9360, age 45-69 years) was examined at baseline in 2003-2005 in the Russian arm of the HAPIEE project. The cohort was re-examined twice and was followed up for end points up to end of 2017 (12.7 years on the average). Fatal end-points were ascertained by local mortality register; the current study focused on CVD deaths. Baseline AF was defined by rest ECG with evaluation by the Minnesota code (MC 8-3-1, 8-3-2; 6-8 with "fibrillation" for atrium). Those with prevalent CVD at baseline and with inadequate ECGs were excluded from analysis; Cox-regression age- and multivariable-adjusted models were estimated.

Results

In total, data on 8565 persons aged 45-69 years at baseline were analyzed. Among those, 145 (1.6%) subjects had AF at baseline and of those 100 subjects had no existing CVD. During the 13-year follow-up, there were 431 cases of CVD death (10.9%) in the cohort, among them 63% (n=272) were fatal coronary heart disease (CHD) and 23% (n=101) were fatal stroke (2.5%). In age-adjusted models, men with baseline AF had increased risk of CVD death (HR=5.76; 95%CI 3.88-8.55), fatal stroke (HR=6.26; 95%CI 2.96-13.22), and fatal CHD (HR=5.86; 95%CI 3.58-9.59). After adjusting for other risk factors, the increased risk remained for all CVD outcomes: 4.49 (95%CI 2.84-7.09) for CVD death, 3.62 (95%CI 1.46-8.96) for fatal stroke, and 4.95 (95%CI 2.81-8.70) for fatal CHD. In women, the age-adjusted HR for CVD death in women with baseline AF was 3.92 (95%CI 1.60-9.62) but in fully-adjusted models the HR was attenuated (HR=2.22; 95%CI 0.87-5.70). The numbers of deaths from CHD and stroke in women were too small for meaningful analyses.

Conclusion

In this urban population-based cohort of subjects free from CVD at baseline, 11% of participants died from CVD death during 13 years follow-up. Men and women with baseline AF had approximately 4-fold increase in CVD mortality risk. The estimated CVD excess mortality risk associated with AF in this Russian cohort is consistent with findings from Western European and North American populations.

Longitudinal trajectories of blood lipid levels in an ageing population sample of Russian Western-Siberian urban population

This study investigated 12-year blood lipid trajectories and whether these trajectories are modified by smoking and lipid lowering treatment in older Russians. To do so, we analysed data on 9,218 Russian West-Siberian Caucasians aged 45-69 years at baseline participating in the international HAPIEE cohort study. Mixed-effect multilevel models were used to estimate individual level lipid trajectories across the baseline and two follow-up examinations (16,445 separate measurements over 12 years). In all age groups, we observed a reduction in serum total cholesterol (TC), LDL-C and non-HDL-C over time even after adjusting for sex, statin treatment, hypertension, diabetes, social factors and mortality (P<0.01). In contrast, serum triglyceride (TG) values increased over time in younger age groups, reached a plateau and decreased in older age groups (> 60 years at baseline). In smokers, TC, LDL-C, non-HDL-C and TG decreased less markedly than in non-smokers, while HDL-C decreased more rapidly while the LDL-C/HDL-C ratio increased. In subjects treated with lipid-lowering drugs, TC, LDL-C and non-HDL-C decreased more markedly and HDL-C less markedly than in untreated subjects while TG and LDL-C/HDL-C remained stable or increased in treatment naïve subjects. We conclude, that in this ageing population we observed marked changes in blood lipids over a 12 year follow up, with decreasing trajectories of TC, LDL-C and non-HDL-C and mixed trajectories of TG. The findings suggest that monitoring of age-related trajectories in blood lipids may improve prediction of CVD risk beyond single measurements.

The relationship between epigenetic age and myocardial infarction/acute coronary syndrome and in a population based nested case-control study

Background

The measure of “epigenetic age” (EA) derived from DNA methylation (DNAm) is considered as biomarker of ageing.

Objective

We investigated the relationship between EA and Myocardial Infarction (MI) /Acute coronary syndrome (ACS) in a nested case-control study of the elderly population.

Methods

A random population sample was examined at baseline (2003/05, n=9360, age 45–69, the Russian arm of the HAPIEE Project), re-examined in 2006/08, 2015/17, and followed up for an average 15 years for fatal and non-fatal events. Using a nested case-control study design, we selected participants with incident MI/ACS (cases) and age-and sex-stratified controls among those free from baseline CVD. We performed DNAm profiling of the whole blood samples (using Illumina EPIC arrays) collected at baseline. After quality control, 135 cases and 185 controls were included in the analysis. Baseline EA was calculated using Horvath, Hannum, PhenoAge and Skin and Blood DNAm clocks; the differences between EA and chronological age (CA) were denoted as DAHr, DAHn, DAPh, DASB, respectively.

Results

DNAm ages calculated with Horvath's, Hannum's and Skin and Blood clocks were close to the CA; the corresponding median absolute differences (MAD) were 3.38, 3.64 and 2.79 years, and mean (SD) −0.85 (5.37), 1.96 (5.18) and 2.10 (3.94) for DAHr, DAHn and DASB respectively. As expected, PhenoAge's predictions were less precise with MAD=9.41 and DAPh mean (SD) 8.94 (6.38). The mean DAHr and DAHn were significantly higher in MI/ACS compared to controls (0.99 (5.38) vs. −1.55 (5.27), p=0.007, and 2.89 (6.37) vs. 1.28 (4.95), p=0.006 correspondingly), DASB was borderline higher in MI/ACS vs controls and DAPh was similar in cases and controls. After controlling for sex, the risk of MI/ACS was higher in DAHr terciles 2 and 3 vs. tercile 1 (OR=1.08 [95% CI 0.61–1.89], p=0.799 and OR=2.09 [1.19–3.66], p=0.010); the association was independent of smoking but it was largely explained (or mediated) by metabolic factors (blood pressure, body mass index, total and LDL-cholesterol). Similarly, the risk of MI/ACS was increased in terciles 2 and 3 of DAHn; compared with lowest tercile, the OR were 1.52 [0.86–2.71], p=0.152 and 2.41 [1.34–4.34], p=0.003), respectively; again, the association was largely explained by metabolic factors. There was no association found between baseline DAPh or DASB and the risk of MI/ACS.

Conclusion

In this case-control study nested in a prospective population-based cohort, we found an association between acceleration of epigenetic age and increased risk of MI/ACS independent of sex and smoking. The risk of MI/ACS was about 2-fold higher in the top tercile of difference between epigenetic and chronological age. The excess risk is appeared to be modulated by metabolic factors.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Russian Science Foundation; Russian Academy of Sciences, Sate Assignment

The frequency and profile of lipid lowering treatment in a contemporary Russian population

Background

Despite of guidelines for management of dyslipidemias (DLP) and the availability of effective and safe lipid lowering drugs (LLD), about one half of CVD patients do not reach the target lipid levels. The knowledge on DLP management in Russian population is limited.

Objective

To analyze the frequency and profile of LLD therapy in subjects with DLP and cardiometabolic diseases in a contemporary Russian population.

Methods

A random population sample of men and women 55–84 years old (n=3898) was examined in 2015–17 in the Russian arm of the HAPIEE project. A composite dysmetabolic group included DLP (total cholesterol, TC ≥5 mmo/l or low-density lipoprotein cholesterol, LDLC ≥3 mmol/l or triglycerides, TG ≥1.7 mmol/l) and/or coronary heart disease (CHD) and/or diabetes mellitus type 2 (DM2). Regular medication intake for 12 months was coded by ATC.

Results

In studied population sample 88% of subjects had dysmetabolic disorders (DLP - 83.1%, CHD - 14.9%, DM2- 20.8%); among them 32.8% subjects received LLD therapy (21.2% in men vs. 39.4% in women, p&lt;0.001) and 17.1% did not report the status of LLD receiving. The frequency of LLD use in CHD group was 48,3%, in DM2 – 35,0%, in DLP – 29.4%. Among named LLD, statins were predominantly used (98%). Lipids control was achieved among subjects with CHD in 18.3% (37.9% among those receiving LLD); among DM2 - in 9.0% (25.6%); among DLP without CHD or DM2 – in 7.3% (24.8%).

Conclusion

In an urban population sample aged 55–84 examined in 2015–17, more than one half of subjects with dysmetabolic disorders (CHD, DM2, DLP) did not receive LLD. Among those receiving lipid-lowering therapy, the lipid control was achieved in about 40% of participants with CHD, and in every forth participant with DM2 or DLP. The lack of lipid control is likely to contribute high rate of atherosclerotic CVD in studied population.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Russian Foundation of Basic Research; Russian Academy of Sciences

Effect of adiposity on differences in carotid plaque burden in studies conducted in Norway and Russia: a cross-sectional analysis of two populations at very different risk of cardiovascular mortality

OBJECTIVES

Large differences exist in the burden of cardiovascular disease (CVD) between Russia and Western European countries including Norway. Obesity prevalence may contribute to the differences. We investigated whether difference in the level of adiposity, assessed using body mass index and waist-to-hip ratio(WHR), could explain intercountry differences in the burden of carotid plaque, a measure of atherosclerosis, in the populations.

DESIGN

Cross-sectional analysis. Logistic and linear regression models were used.

SETTING

We used population-based cross-sectional Know Your Heart (KYH) study in Russia and the Tromsø 7 study (Tromsø 7) in Norway.

PARTICIPANTS

3262 and 1800 men and women aged 40-69 years in KYH and Tromsø 7, respectively.

PRIMARY AND SECONDARY OUTCOME

The presence of carotid plaques and plaque score assessed using ultrasound.

RESULTS

The presence of carotid plaques and plaque score were higher in KYH than Tromsø 7 regardless of age group and sex. A positive association between carotid plaque burden and adiposity was found (OR of having at least one plaque per SD in WHR 1.18 (95% CI 1.06 to 1.31) for men; 1.15 (1.06 to 1.25) for women)) adjusted for age, smoking and education in a pooled analysis of the two studies. There was little evidence of the interaction between study and adiposity. These effects did not differ between the two studies. However, neither adiposity nor CVD risk factors (smoking, systolic blood pressure, cholesterol, glycosylated haemoglobin) explained the higher carotid plaque burden in KYH compared with Tromsø 7.

CONCLUSION

Adiposity, especially abdominal adiposity, is a risk factor for carotid plaque in Russia and Norway, although neither adiposity nor established CVD risk factors explained the higher plaque burden in Russia. To reduce the CVD burden in Russia, beyond prevention and treatment of adiposity, further research is required to understand why Russia has a high burden of atherosclerosis.

Uncontrolled and apparent treatment resistant hypertension: a cross-sectional study of Russian and Norwegian 40-69 year olds

BACKGROUND

Uncontrolled hypertension is a major cardiovascular risk factor. We examined uncontrolled hypertension and differences in treatment regimens between a high-risk country, Russia, and low-risk Norway to gain better understanding of the underlying factors.

METHODS

Population-based survey data on 40-69 year olds with hypertension defined as taking antihypertensives and/or having high blood pressure (140+/90+ mmHg) were obtained from Know Your Heart Study (KYH, N = 2284), Russian Federation (2015-2018) and seventh wave of The Tromsø Study (Tromsø 7, N = 5939), Norway (2015-2016). Uncontrolled hypertension was studied in the subset taking antihypertensives (KYH: N = 1584; Tromsø 7: 2792)and defined as having high blood pressure (140+/90+ mmHg). Apparent treatment resistant hypertension (aTRH) was defined as individuals with uncontrolled hypertension on 3+ OR controlled on 4+ antihypertensive classes in the same subset.

RESULTS

Among all those with hypertension regardless of treatment status, control of blood pressure was achieved in 22% of men (KYH and Tromsø 7), while among women it was 33% in Tromsø 7 and 43% in KYH. When the analysis was limited to those on treatment for hypertension, the percentage uncontrolled was higher in KYH (47.8%, CI 95 44.6-50.9%) than Tromsø 7 (38.2, 36.1-40.5%). The corresponding figures for aTRH were 9.8% (8.2-11.7%) and 5.7% (4.8-6.8%). Antihypertensive monotherapies were more common than combinations and used by 58% in Tromsø 7 and 44% in KYH. In both KYH and Tromsø 7, untreated hypertension was higher in men, those with no GP visit in the past year and problem drinkers. In both studies, aTRH was associated with older age, CVD history, obesity, and diabetes. In Tromsø 7, also male gender and any drinking. In KYH, also chronic kidney disease.

CONCLUSION

There is considerable scope for promoting combination therapies in line with European treatment guidelines in both study populations. The factors associated with untreated hypertension overlap with known correlates of treatment non-adherence and health check non-attendance. In contrast, aTRH was characterised by obesity and underlying comorbidities potentially complicating treatment.

Know Your Heart: Rationale, design and conduct of a cross-sectional study of cardiovascular structure, function and risk factors in 4500 men and women aged 35-69 years from two Russian cities, 2015-18

Russia has one of the highest rates of cardiovascular disease in the world. The International Project on Cardiovascular Disease in Russia (IPCDR) was set up to understand the reasons for this. A substantial component of this study was the Know Your Heart Study devoted to characterising the nature and causes of cardiovascular disease in Russia by conducting large cross-sectional surveys in two Russian cities Novosibirsk and Arkhangelsk. The study population was 4542 men and women aged 35-69 years recruited from the general population. Fieldwork took place between 2015-18. There were two study components: 1) a baseline interview to collect information on socio-demographic characteristics and cardiovascular risk factors, usually conducted at home, and 2) a comprehensive health check at a primary care clinic which included detailed examination of the cardiovascular system. In this paper we describe in detail the rationale for, design and conduct of these studies.

Know Your Heart: Rationale, design and conduct of a cross-sectional study of cardiovascular structure, function and risk factors in 4500 men and women aged 35-69 years from two Russian cities, 2015-18

Russia has one of the highest rates of cardiovascular disease in the world. The International Project on Cardiovascular Disease in Russia (IPCDR) was set up to understand the reasons for this. A substantial component of this study was the Know Your Heart Study devoted to characterising the nature and causes of cardiovascular disease in Russia by conducting large cross-sectional surveys in two Russian cities Novosibirsk and Arkhangelsk. The study population was 4542 men and women aged 35-69 years recruited from the general population. Fieldwork took place between 2015-18. There were two study components: 1) a baseline interview to collect information on socio-demographic characteristics and cardiovascular risk factors, usually conducted at home, and 2) a comprehensive health check at a primary care clinic which included detailed examination of the cardiovascular system. In this paper we describe in detail the rationale for, design and conduct of these studies.

Know Your Heart: Rationale, design and conduct of a cross-sectional study of cardiovascular structure, function and risk factors in 4500 men and women aged 35-69 years from two Russian cities, 2015-18

Russia has one of the highest rates of cardiovascular disease in the world. The International Project on Cardiovascular Disease in Russia (IPCDR) was set up to understand the reasons for this. A substantial component of this study was the Know Your Heart Study devoted to characterising the nature and causes of cardiovascular disease in Russia by conducting large cross-sectional surveys in two Russian cities Novosibirsk and Arkhangelsk. The study population was 4542 men and women aged 35-69 years recruited from the general population. Fieldwork took place between 2015-18. There were two study components: 1) a baseline interview to collect information on socio-demographic characteristics and cardiovascular risk factors, usually conducted at home, and 2) a comprehensive health check at a primary care clinic which included detailed examination of the cardiovascular system. In this paper we describe in detail the rationale for, design and conduct of these studies.

Context-dependency of the relation between left ventricular mass and AGT gene variants

In the European Project on Genes in Hypertension (EPOGH), we investigated in three populations to what extent in a family-based study, left ventricular mass (LVM) was associated with the C-532T and G-6A polymorphisms in the angiotensinogen (AGT) gene. We randomly recruited 221 nuclear families (384 parents and 440 offspring) in Cracow (Poland), Novosibirsk (Russia), and Mirano (Italy). Echocardiographic LVM was indexed to body surface area, adjusted for covariables, and subjected to multivariate analyses, using generalized estimating equations and quantitative transmission disequilibrium tests in a population-based and family-based approach, respectively. We found significant differences between the two Slavic centres and Mirano in left ventricular mass index (LVMI) (94.9 vs 80.4 g/m2), sodium excretion (229 vs 186 mmol/day), and the prevalence of the AGT -6A (55.7 vs 40.6%) and -532T (16.8 vs 9.4%) alleles. In population-based as well as in family-based analyses, we observed positive associations of LVMI and mean wall thickness (MWT) with the -532T allele in Slavic, but not in Italian male offspring. Furthermore, in Slavic male offspring, LVMI and MWT were significantly higher in carriers of the -532T/-6A haplotype than in those with the -532C/-6G or -532C/-6A allele combinations. In women, LVMI was neither associated with single AGT gene variants nor with the haplotypes (0.19 < P <0.98). In Slavic offspring carrying the AGT -532C/-6G or -532C/-6A haplotypes, LVMI significantly increased with higher sodium excretion (+3.5 g/m2/100 mmol; P=0.003), whereas such association was not present in -532T/-6A haplotype carriers (P-value for interaction 0.04). We found a positive association between LVMI and the AGT -532T allele due to increased MWT. This relation was observed in Slavic male offspring. It was therefore dependent on gender, age and ecogenetic context, and in addition it appeared to be modulated by the trophic effects of salt intake on LVM.

Ambulatory blood pressure and left ventricular structure and function in relation to the G-protein beta3-subunit polymorphism C825T in White Europeans

The 825T allele of the G-protein beta(3)-subunit is associated with increased intracellular signalling. Its association with hypertension is inconsistent. We, therefore, studied the C825T polymorphism in relation to ambulatory blood pressure as well as left ventricular structure and function in two European populations. We genotyped 248 parents and 318 offspring, enrolled in the European Project on Genes in Hypertension in Cracow, Poland (n=286) and in Novosibirsk, Russian Federation (n=280). The 24-h ambulatory blood pressure was recorded using oscillometric SpaceLabs 90207 monitors. Within each centre, a single observer performed two-dimensionally guided M-mode echocardiography and Doppler sonography to measure left ventricular structure (American Society of Echocardiography conventions) and diastolic function: early (E) and late (A) peak diastolic inflow velocities. We used analysis of covariance and generalized estimating equations to allow for covariables and nonindependence among related subjects. Genotype frequencies were similar (P=0.25) in Cracow and Novosibirsk and amounted to 44.7% for CC, 47.2% for CT, and 8.1% for TT. Among parents (mean age: 51.3 years)-but not among offspring (mean age 25.1 years)-24-h, daytime and night time systolic blood pressures were 5-6 mmHg higher in TT homozygotes than in C allele carriers. In TT homozygous parents (-8.2 cm/sec, P=0.004) as well as in TT homozygous offspring (-7.5 cm/sec, P=0.02), the E-wave was significantly reduced, which in offspring also resulted in a lower E/A ratio (-0.25, P=0.002). Neither in parents nor in offspring, left ventricular mass index was associated with the C825T polymorphism. In conclusion, in TT homozygotes of both generations, early left ventricular relaxation was reduced. In TT homozygous parents, the latter observation might be because of the higher systolic pressure associated with the TT genotype.

Hemielliptic proximal isovelocity surface area method modified for clinical application: more accurate quantification of mitral regurgitation in Doppler echocardiography

The proximal isovelocity surface area (PISA) method is one of the various methods used for quantitatively estimating mitral regurgitation. The PISA shape is hemielliptic rather than hemispheric on a slit-like orifice, and the hemielliptic method is more accurate than the hemispheric method for in vitro studies. Nevertheless, the hemispheric method is used clinically because of its simplicity, whereas the hemielliptic method is difficult to approach from 3 orthogonal directions. The present study tries to establish a modified hemielliptic method for use in clinical applications. A closed-circuit, constant flow system was designed to simulate PISA, and various types of slit-like orifices were selected. Three orthogonal PISA radii were measured and flow rates were calculated using the original hemielliptic formula from the 3 orthogonal radii. Flow rates were also calculated indirectly using a linear regression formula, and PISA radii from a bird's eye approach and lateral approaches (modified hemielliptic method) were compared. Flow rates that were determined using the original hemielliptic method correlated significantly with actual flow rates (r = 0.92, p < 0.0001; y = 1.1x - 13; SEE = 13.63 ml/s). Similarly, flow rates calculated using the modified hemielliptic method correlated significantly with actual flow rates (r = 0.90, p < 0.001; y = 0.94x - 0.78; SEE = 14.13 ml/s). The study's results imply that the modified hemielliptic method can be used to accurately quantify mitral regurgitation and could be applied for clinical examinations.

Antihypertensive treatment modulates the association between the D/I ACE gene polymorphism and left ventricular hypertrophy: a meta-analysis

This meta-analysis attempted to derive pooled estimates for the putative association between echocardiographic or electrocardiographic left ventricular hypertrophy and the deletion/insertion (D/I) polymorphism of the angiotensin-I converting enzyme. Case-control studies were combined, using the Mantel and Haenszel approach. Joint P-values for continuous variables were calculated by Stouffer's method. Continuous measurements of left ventricular mass, which were reported in different units, were expressed on a percentage scale using the within-study mean of the II genotype as the denominator. The computerised database used for this analysis, included 28 reports with an overall sample size of 6638 subjects. The prevalence of the D allele was significantly lower in Japanese (37.2%) than in Caucasians (56.2%). A funnel plot including 12 case-control studies (4094 subjects) suggested that no publication bias was present. Overall, left ventricular hypertrophy was not associated with the D allele. Compared with the II genotype, the excess risks of left ventricular hypertrophy associated with DD and DI genotypes were only 14% (95% CI: 0.92-1.42; P = 0.23) and 5% (95% CI: 0.87-1.28; P = 0.61), respectively. However, the sensitivity analysis showed that in untreated hypertensive patients the DD genotype, compared with II homozygozity, was associated with a 192% (P = 0.002) higher risk of left ventricular hypertrophy. If left ventricular mass was analysed as a continuous trait across 23 studies (5438 subjects), overall no association with the D/I polymorphism was present. However, if untreated hypertensive patients were analysed separately, echocardiographic left ventricular mass was on average 10.1% (95% CI: 4.8-15.5%; P = 0.001) higher in DDhomozygotes than in the II reference group. Thus, in untreated hypertensive patients, in case-control studies as well as association studies, the D allele behaved as a marker for left ventricular hypertrophy. These findings support the hypothesis that the enhanced ACE activity associated with the D allele may promote left ventricular hypertrophy if a pathophysiologic process causing this disorder, remains unopposed by treatment.

Left ventricular hypertrophy in northern and Siberian populations

Characteristics of left ventricular hypertrophy (LVH) were investigated in random samples of the Chukotka coastal Native population (131 males) and in the urban Novosibirsk population (627 males) aged 30-59. Standard epidemiological methods employing electrocardiography (EKG) and echocardiography (EchoCG) were used. The frequency of EKG-LVH in the urban population was about six percent. The prevalence of LVH in Chukotka was more than twice as high as in Novosibirsk, as determined by both EKG and EchoCG criteria. About half of EchoCG-LVH cases in Natives and one-fifth of those in the city population could not be explained by conventional reasons. Advanced family surveys in Novosibirsk established the fact that myocardial hypertrophy exhibits a family aggregation in first-degree relatives of normotensive probands affected by LVH. The data demonstrate an inherited predisposition for LVH and suggest the need for molecular-genetic analysis.