Epidemiology studies prevalence and determinants of diseases in order to control and prevent health problems. History, aims and tasks of epidemiology are still unclear for researchers and clinicians, although modern evidencebased medicine is based on results of epidemiological observational and interventional studies. Paper gives an overview of epidemiology development and paradigm changes since first attempts by John Graunt until modern conception of prevention paradox suggested by Geoffrey Rose. There is a phenomenon of “epidemiological transition” which is associated with the predominance of non-communicable diseases, in particular, of cardioand cerebrovascular diseases, chronic obstructive pulmonary disease, metabolic disorders, oncological diseases, traumas and stress-related problems, as the main reasons of morbidity and mortality. Currently, there is further progress in epidemiology — population genetics, environmental epidemiology and aging, pharmacoepidemiology and translational epidemiology are becoming more and more popular. Among modern problems of epidemiology, the storing and analysis of Big Data, as well as the necessity of the improvement in data storage and privacy are among the main issues under discussion.

Objective. To estimate the association between metabolic syndrome (MS) and its components with markers of subclinical target organ damage (TOD) in otherwise healthy bank employees.

Design and methods. A sample of 383 participants with at least 1 component of MS and without cardiovascular complications was randomly selected from a cohort of bank employees (n = 1600). Mean age of participants was 46,6 ± 9,0 years, 66,3 % were females (n = 254). Anthropometry, fasting lipids, creatinine (estimated glomerular filtration rate calculation, eGFR), and fasting glucose were performed according to standard procedures. In all patients echocardiography (left ventricular myocardial mass index assessment, LVMMI), carotid ultrasound (atherosclerotic plaques and intima-media thickness evaluation, IMT), arterial stiffness (pulse wave velocity measurement, PWV), ankle-brachial index, and urine albumin were assessed.

Results. Patients with MS (n = 229; 50,9 %) had significantly higher prevalence of atherosclerotic plaques (n = 29; 12,7 % vs. n = 9; 5,7 %; p = 0,03) and low eGFR (81,3 ± 13,1 vs. 84,3 ± 13,7 ml/min/m 3; р = 0,03) compared to patients without MS. All markers of subclinical TOD were associated with age based on multiple linear regression. Blood pressure correlated with LVMMI and
PWV, hypercholesterolemia — with increased IMT, hypertriglyceridemia — with PWV, and LVMMI — with waist circumference. There was no association between MS and TOD markers.

Conclusions. Left ventricular hypertrophy was detected more often in females (probably due to higher prevalence of abdominal obesity), while carotid atherosclerotic lesions were more frequently found in males (possibly due to higher prevalence of hypertriglyceridemia). TOD was more profound with the higher number of MS components, in particular, atherosclerotic plaques and decreased eGFR. Individual components of MS (hypertension, obesity, dyslipidemia) and age were the main factors associated with structural changes of cardiovascular system, but no effect was
found for MS as a cluster.

Objective. To estimate the prevalence of subclinical organ damage by basic existing screening methods, and correlation with traditional risk factors in a sample of St Petersburg inhabitants.

Design and methods. The study was carried out as a part of ESSE-RF study. Totally, 1592 St Petersburg inhabitants (567 men and 1025 women) were examined. Anthropometry, blood pressure measurement and biochemistry were performed according to standard protocols. During instrumental investigation intima-media thickness (IMT) by My Sono U6; carotid-femoral pulse wave velocity (cfPWV), cardio-ankle vascular index (CAVI) and ankle brachial index (ABI) by VaSera VS‑1500 were assessed. Сardiovascular risk was assessed by SCORE-scale.

Results. There is no subclinical vascular damage found in the majority of participants (n = 955, 76,7 %). The highest prevalence of subclinical organ damage is detected in patients with low and intermediate SCORE risk. Increasing of IMT more than 0,9 mm is the most prevalent marker (n = 212, 24,7 %) and ABI lower than 0,9 (n = 18, 2,1 %) was the less prevalent marker comparing with other methods. IMT correlates with waist circumference and BMI; besides this, a correlation with systolic BP is found only in women. Cardiovascular risk score correlated with CAVI, ABI and IMT. СfPWV and CAVI mean values, prevalence of IMT > 0,9 mm are significantly higher in males comparing with females. Only association between cfPWV and IMT is significant (β = 0,43, p < 0,0001).

Conclusion. Low prevalence of subclinical organ damage is revealed according to different diagnostic methods. Evaluation of subclinical organ damage is reasonable for patients with low and intermediate risk; the risk level according to SCORE correlates with CAVI, ABI and IMT data. The prevalence of high CAVI and IMT is higher among men with hypertension, hypertriglyceridemia and hyperglycemia. Increased CAVI is associated with high blood pressure, larger prevalence of hypertension and older age; among women with hypertriglyceridemia and hyperglycemia also.

Objective. To develop a technique for prediction of low adherence to the secondary prevention (ASP) of hypertension (HTN), based on the assessment of medical and social factors in coal miners.

Design and methods. The medical and social cardiovascular risk factors, anxiety levels, as well as ASP, treatment and quality of life were studied in coal miners within the complex repeated medical xamination. The individual risk of low ASP was defined using the pattern of recognition of the maximum likelihood.

Results. Nine significant factors were found to be associated with the high risk of low ASP. Based on the obtained data, the prediction technique of low ASP was developed.

Conclusions. High prevalence of cardiovascular diseases and HTN among coal miners requires proper application of primary and secondary prevention measures with a major role given to the measures aimed at improving ASP. The factors affecting ASP level in coal miners included gender, age, bad habits, levels of reactive and personal anxiety, quality of life. The method of maximum likelihood with the prediction scale allows both conducting a comprehensive assessment of the individual risk of low ASP and efficiency of the treatment and prevention programs.

The aim of the current study was to analyse an association between ADRB1, ADRB2 и ADRB3 gene variants and essential hypertension (EH) in the ethnic group of Tatars residing in the Republic of Bashkortostan (Russian Federation).

Design and methods. We performed genotyping of ADRB1 rs1801252, ADRB2 rs1042713 and ADRB3 rs4994 polymorphisms using polymerase-chain reaction with allele-specific primers in the study group consisting of 530 individuals (216 hypertensive patients, 314 controls). Considering the fact that gender is a major risk factor for the development of hypertension before age 45, the study group was composed of male individuals.

Results. We detected an association between ADRB2 rs1042713 and EH. ADRB2*A/G genotype was found to be associated with an increased risk of EH (odds ratio, OR = 1,68; p = 0,004); ADRB2*G/G genotype, on the contrary, was shown to be protective against the disease (OR = 0,58; p = 0,01). ADRB2*A/G genotype also marked an increased risk of hypertension in patients with obesity (OR = 3,01; P = 0,01), while ADRB2*G/G genotype carriers with body mass index > 30 kg/m 2 had lower risk of EH (OR = 0,29; P = 0,01) when compared to the control individuals of the same category.

Conclusion. Our study has shown that ADRB2 rs1042713 polymorphism is associated with the risk of EH, and the effect is more pronounced in individuals with obesity.

Objective. To study the prevalence of the genetic risk factors and their role in the formation of hypertension and its risk factors among indigenous population of Mountain Shoria (Shors).

Design and methods. A clinicalepidemiological study of Mountain Shoria indigenous populations at isolated regions was undertaken. We examined 395 people by continuous method, the sample included adult population (aged 18 years and older). We studied anthropometric data, blood lipids, and polymorphisms of the genes ADRB1 (Ser49Gly, A/G, rs1801252) ADRA2B (I/D), ACE (I/D), eNOS (4a/4b) and MTHFR (C677T, Ala222Val, rs1801133).

Results. Mean levels of triglycerides, total cholesterol, very low density lipoproteins and atherogenic index were higher among people with homozygous DD genotype ADRA2B gene. D allele of the ADRA2B gene was found 2,8‑times more frequently among Shors with obesity in comparison to the population with normal weight. There is a 7,9‑time higher relative risk to detect D allele of the ACE gene among people with hypercholesterolemia than among people with normal levels of total cholesterol, and it is 11,2 times higher in group with hyperbetacholesterolemia than in group with normal levels of low density lipoprotein cholesterol. A allele homozygotes of the ADRB1 gene have 1,6 times higher risk of hypertension development in comparison with G allele homozygotes and heterozygotes.

Conclusions. Ther is a relation between Ser49Gly polymorphism of ADRB1 gene with atherogenicity index, I/D polymorphism ADRA2B gene with triglyceride level, low density lipoprotein cholesterol, atherogenic index, I/D polymorphism of ACE gene and the levels of total cholesterol and low density lipoprotein cholesterol. D allele of ADRA2B gene is associated with obesity, and abnormal fat distribution. An allele of ADRB1 gene is associated with the higher relative risk of hypertension progression in Shor population.

Objective. To determine the gender differences influence of personal anxiety (PA) in the risk of hypertension development in the open population aged 25–64 years old in Russia/Siberia.

Design and methods. As part of the G program III WHO “MONICA-psychosocial” a random representative sample including both sexes aged 25–64 years old was surveyed in Novosibirsk in 1994 (males: n = 657 44,3 ± 0,4 years, response — 82,1 %; women: n = 689, 45,4 ± 0,4 years, response — 72,5 %). The survey included registration of socio-demographic data, and assessment of PA (test Spielberger CD, 1972). During 16‑year follow-up 229 cases of new-onset hypertension (HTN) among women and 46 cases among men were identified.

Results. In an open population of 25–64 high level of anxiety (HLA) was detected in 59,9 % of women and 50,9 % men. After 5 years, in population aged 25–64 years old the hazard risk (HR) of HTN development was higher in men (HR = 5) than in women (HR = 2,3) in the presence of HLA; the same results were found in 10 years. However, when considering subgroups, women aged 55–64 years old with HLA had higher HTN risk (10‑fold) than men (7,9‑fold) in 10 years. Multivariate Cox regression analysis showed that HLA had the greatest impact on the risk of HTN in female population aged 55–64 years old (HR = 7,9); among men, HLA is associated with the higher HTN risk in divorced (HR = 4,3) and widowed (HR = 4,8) subjects, and in males aged 55–64 years old (HR = 5,5).

Conclusion. We found greater prevalence of HLA traits in women compared to men. At the same time the risk of HTN is higher in men with HLA than in women aged 25–64 years, except for the older age groups. 

Objective. To evaluate melatonin (MT) excretion patterns in patients with polymorbid cardiovascular diseases (coronary artery disease, hypertension, metabolic syndrome), anxiety and depressive disorders, and to determine the targets for therapeutic intervention in this group of patients.

Design and methods. The study included 40 men (mean age — 37,11 ± 6,93 years) with polymorbid cardiovascular diseases and 10 healthy men (mean age — 37,5 ± 4,95 years). We used complex psychological test methods, laboratory tests and instrumental evaluation of the cardiovascular system. The 6‑sulfatoxymelatonin (6‑SMT) was assessed by ELISA using kits «BÜHLMANNEKM6S».

Results. The circadian blood pressure profile was abnormal in most of the patients with the change from «dipper» pattern to «non-dipper» or «night-peaker». Nocturnal excretion of 6‑SMT was significantly lower in the second group compared to the first, third and fourth groups, but there were no significant changes in its daily excretion (p < 0,001). The rate «mild depression» and «subclinical anxiety» symptoms was 86,6 % in the studied groups with polymorbid cardiovascular diseases (p < 0,001). The signs of «severe depression» were found in 92,3 % of patients in group 2 (p < 0,001), while «clinical anxiety» was present in 91,6 % of patients in group 3 (p < 0,001).

Conclusions. Patients with polymorbid cardiovascular diseases show abnormal MT levels, characterized by the decrease of night and increased daytime excretion of 6‑SMT. It is more prominent in depressive patients compared to healthy ones and to individuals with anxiety syndrome (p < 0,001). In patients with polymorbid cardiovascular diseases cardiotropic and antihypertensive therapy might be in particular required during the followed time periods: during second part of nocturnal sleep (03:00–06:00) and during the first hours after morning awakening (06:00–08:00).

Objective. To evaluate the impact of clinical, hemodynamic, metabolic and inflammatory indicators on the state of vascular reactivity and glomerular filtration rate in patients with arterial hypertension (HTN) in combination with type 2 diabetes mellitus (T2DM).

Design and methods. We carried out a comparative descriptive study of two parallel groups of young and middle-aged patients with HTN 1–2 degrees: 72 patients with T2DM (group 1) and 61 patients without T2DM (group 2). We determined anthropometric, metabolic indicators, intima-media thickness (IMT) and endothelium-dependent vasodilation (EDVD) of brachial artery (BA) using a cuff test, glomerular filtration rate (GFR), the levels of interleukin‑1β and TNF-α, and 24‑h blood pressure (BP) monitoring was performed in all patients.

Results. The BA diameter, EDVD indicators, cytokine activity were lower, while night SBP and 24h DBP time index were higher in group 1 compared to group 2. Based on the multivariate analysis the Models Summary were calculated for predicting GFR values and EDVD depending on the presence of T2DM, they explained ≥ 84,0 %
variability of these parameters.

Conclusions. We have developed the models to calculate the values EDVD, including common parameters for both groups (BA diameter, IMT, gender) and different indicators (time index of nocturnal DBP for the patients with T2DM; body mass index, 24‑h time index of DBP, TNF-α for the patients without T2DM). An independent association between GFR and time indices of daytime SBP, 24‑h SBP, left ventricular myocardial mass index and duration of T2DM was found only in group 1.

Objective. To study the rate of long QTc and JTc intervals in sleep-wakefulness cycle, and also their relationship with severity of obstructive sleep apnea-hypopnea syndrome (OSA) in patients with newly diagnosed hypertension (HTN).

Design and methods. 24‑hour multifunctional monitoring was conducted in 59 male patients (age 38,0 ± 7,7 years old; body mass index 33,8 ± 5,4 kg/m 2) with elevated office blood pressure, who did not receive any medications. All patients had two or more risk factors of HTN. Organ damage was identified in 12 (20 %) patients. The long QTc interval was defined as 450 msec or more, automatic analysis was performed using 8‑lead dynamic ECG.

Results. OSA was diagnosed in 40 (68 %) patients: 17 patients had mild sleep apnea (apneahypopnea index, AHI, from 5 to 14 episodes per hour), the rest of the patients had moderate and severe OSA (AHI from 18 to 97 episodes per hour). Nineteen (32 %) patients without OSA were included in the comparison group (AHI less than 5 episodes per hour). There was no differences in average heart rate during assessed time periods between the groups. There was a direct positive correlation between duration of QTc and JTc calculated separately for periods of wakefulness, sleep and AHI and hypoxemia index.

Conclusions. More than 50 % of patients with newly diagnosed AH and OSA without associated cardiovascular diseases demonstrate changes in myocardial repolarization throughout sleep-wakefulness cycle. These changes are associated with the number of apneas/hypopneas and the severity of hypoxemia during sleep

Background. Obstructive sleep apnea syndrome (OSAS) and respiratory disorders during sleep occur in every tenth patient. Moreover, sleep disorders are found in every second patient with cardiovascular diseases. In practice, however, it is diagnosed only in 10–20 % patients with OSAS. This is due to the lack of specific symptoms; and, moreover, frequently OSAS has the guise of cardiovascular disease, hence it can remain misdiagnosed for a
prolonged period of time.

Objective. This work, based on case reports, demonstrates how OSAS may influence cardiovascular diseases.

Case reports. This paper presents several clinical cases of OSAS masked by the following cardiovascular conditions: hypertension, chronic heart failure, cardiac arrhythmias and coronary heart disease.

Conclusions. Practicing physicians should be aware of the possibility of OSAS and should ask the patient in detail in order to verify the diagnosis. Timely treatment of moderate and severe OSAS, in addition to traditional treatment, can improve the outcomes in these patients. There are different treatment approaches in obstructive sleep apnea, such as CPAP (continuous positive airway pressure) therapy, surgical methods (uvuloplasty, septoplasty), didgeridoo playing, injections of botulinum toxin in palatine arch, implantation of electrodes in the chest area and the upper respiratory tract and other. CPAP is currently the most effective way of OSAS managment, however, its impacy on cardiovascular outcomes is still unclear and requires further research.

Objective. To evaluate possible role of endocannabinoid (EC) serum levels, such as anandamide (AEA) and 2‑arachidonoylglycerol (2‑AG), on formation of cognitive impairment in hypertensive and obese patients.

Design and methods. Altogether 117 patients (mean age 46,7 ± 5,9 years) with essential hypertension and abdominal obesity were included. The control group included 25 nonobese normotensive patients (mean age 45,3 ± 5,8 years). Comprehensive neuropsychological testing was conducted. Serum levels of AEA and 2‑AG were measured by liquid chromatography-mass spectrometry.

Results. The ROC analysis showed an AUC (Area Under Curve) value for 2‑AG 0,74 ± 0,077 и 0,54 ± 0,099 for anandamide that corresponds to the good diagnostic efficacy of 2‑AG and unsatisfactory efficacy of anandamide. Maximum threshold value for 2‑AG, defining the risk of cognitive impairment (sensitivity — 83,3 %, specificity — 64,3 %) was 5,4 ng/ml. We also calculated relative risk of cognitive impairment in the groups of patients with different levels of 2‑AG in accordance with the threshold value. The relative risk of cognitive impairment in patients with 2‑AG > 5,4 ng/ml was 2,14 (95 % confidence interval 1,14 to 4,04, p = 0,019) compared to those with 2‑AG < 5,4 ng/ml.

Conclusions. In obese and hypertensive patients with plasma 2‑AG level more than 5,4 ng/ml the risk of cognitive impairment is 2,14 times higher compared to patients with 2‑AG plasma level less or equal to 5,4 ng/ml.