Heart failure care in the Central and Eastern Europe and Baltic region: status, barriers, and routes to improvement.

Despite improvements over recent years, morbidity and mortality associated with heart failure (HF) are higher in countries in the Central and Eastern Europe and Baltic region than in Western Europe. With the goal of improving the standard of HF care and patient outcomes in the Central and Eastern Europe and Baltic region, this review aimed to identify the main barriers to optimal HF care and potential areas for improvement. This information was used to suggest methods to improve HF management and decrease the burden of HF in the region that can be implemented at the national and regional levels. We performed a literature search to collect information about HF epidemiology in 11 countries in the region (Bulgaria, Croatia, Czechia, Estonia, Hungary, Latvia, Lithuania, Poland, Romania, Serbia, and Slovenia). The prevalence of HF in the region was 1.6-4.7%, and incidence was 3.1-6.0 per 1000 person-years. Owing to the scarcity of published data on HF management in these countries, we also collected insights on local HF care and management practices via two surveys of 11 HF experts representing the 11 countries. Based on the combined results of the literature review and surveys, we created national HF care and management profiles for each country and developed a common patient pathway for HF for the region. We identified five main barriers to optimal HF care: (i) lack of epidemiological data, (ii) low awareness of HF, (iii) lack of national HF strategies, (iv) infrastructure and system gaps, and (v) poor access to novel HF treatments. To overcome these barriers, we propose the following routes to improvement: (i) establish regional and national prospective HF registries for the systematic collection of epidemiological data; (ii) establish education campaigns for the public, patients, caregivers, and healthcare professionals; (iii) establish formal HF strategies to set clear and measurable policy goals and support budget planning; (iv) improve access to quality-of-care centres, multidisciplinary care teams, diagnostic tests, and telemedicine/telemonitoring; and (v) establish national treatment monitoring programmes to develop policies that ensure that adequate proportions of healthcare budgets are reserved for novel therapies. These routes to improvement represent a first step towards improving outcomes in patients with HF in the Central and Eastern Europe and Baltic region by decreasing disparities in HF care within the region and between the region and Western Europe.

Extrahepatic Vitamin K-Dependent Gla-Proteins-Potential Cardiometabolic Biomarkers.

One mechanism to regulate pathological vascular calcification (VC) is its active inhibition. Loss or inactivation of endogenic inhibitors is a major inductor of VC. Such inhibitors are proteins rich in gamma-glutamyl residues (Gla-proteins), whose function strongly depends on vitamin K. The current narrative review is focused on discussing the role of extrahepatic vitamin K-dependent Gla-proteins (osteocalcin, OC; matrix Gla-protein, MGP; Gla-rich protein, GRP) in cardio-vascular pathology. Gla-proteins possess several functionally active forms whose role in the pathogenesis of VC is still unclear. It is assumed that low circulating non-phosphorylated MGP is an indicator of active calcification and could be a novel biomarker of prevalent VC. High circulating completely inactive MGP is proposed as a novel risk factor for cardio-vascular events, disease progression, mortality, and vitamin K deficiency. The ratio between uncarboxylated (ucOC) and carboxylated (cOC) OC is considered as an indicator of vitamin K status indirectly reflecting arterial calcium. Despite the evidence that OC is an important energy metabolic regulator, its role on global cardio-vascular risk remains unclear. GRP acts as a molecular mediator between inflammation and calcification and may emerge as a novel biomarker playing a key role in these processes. Gla-proteins benefit clinical practice as inhibitors of VC, modifiable by dietary factors.

Blood pressure reduction in difficult-to-control patients and the effect of a nurse-led program in Bulgaria.

Hypertension is a major contributor to cardiovascular morbidity and mortality. Although there has been significant improvement in blood pressure (BP) control during the last decades, it is still far from optimal. Several strategies for hypertension management have been proposed, and among all - nurse-led programs seem encouraging. AIM: To evaluate the effect of a complex nurse program aiming to reduce BP in patients with uncontrolled hypertension. PATIENTS AND METHODS: In a cardiologist's office, a trained nurse included patients with uncontrolled hypertension and newly referred patients with high BP in a program for hypertension management. It consisted of patient education, assessment of quality of life, lifestyle advice, medication improvement and adherence stimulation. All patients were followed for 6 months and their BP, lifestyle indicators, and quality of life measurements were recorded. Statistical analyses included two- and one sample t-tests, chi-square test, correlation and multivariate linear regression. RESULTS: Overall, 47 patients, presenting with uncontrolled hypertension and with BP>140/90 mm Hg were included in this research. Their BP was reduced within 6 months by mean 30 /11 mm Hg and after 6 months, from 162/88 to 133/77 mm Hg. The drop of BP values was present at the first month with mean BP 140/82 mm Hg. Control of hypertension improved from 2% to 55% at the 1st month mark and to 79% at the 6th month, p<0.0001. The decrease in SBP was positively correlated to decrease in waist circumference, p = 0.47, p = 0.009. In multivariate linear regression analysis, the difference in BP was significantly related to self-assessment health scoring and marginally significant with renal impairment. CONCLUSIONS: The development of a complex nurse-led program, tailored to patients with uncontrolled hypertension, leads to significant positive effect on BP decrease and improves hypertension control in primary care. This may be cost effective and improve BP control in low- to middle-income countries.

Dietary Behavior and Compliance to Bulgarian National Nutrition Guidelines in Patients With Type 1 Diabetes With Longstanding Disease.

Introduction: Nutrition education attempts to maintain and enhance good eating habits to achieve optimal metabolic control in people with type 1 diabetes (T1D). Recommendations for patients with T1D are comparable to those of the general population. This Study Aimed: To investigate dietary habits and adherence to nutritional recommendations of patients with T1D as compared with age, gender, and BMI matched people in Bulgaria. Methods: A case-control study included 124 patients with T1D with long disease duration (mean duration 25.3 ± 8.2 years) followed up at a diabetes clinic in Varna, Bulgaria for 2 years (2017-2019) and 59 controls matched for gender, age and BMI. A 24-h dietary recall method was used to assess the nutrition of both groups. A standardized questionnaire was applied to assess the frequency of food consumption (Feel4Diabtes). Height and weight were standardly measured, and BMI was calculated. Findings were compared with Bulgarian recommendations and reference values for energy and nutrient intake for healthy adults. The data were analyzed with the statistical package SPSSv21.0 and Jamovi v.22.5. Results: The nutritional characteristics of T1D men and women differ. Men with T1D had a higher intake of total carbohydrates (CHO) (p = 0.009), a lower intake of total fats (p = 0.007), and monounsaturated fatty acids (p = 0.029) as a percentage of total daily energy compared with the controls. Women with T1D had a different distribution of energy intake per meal compared to controls: they consumed more energy (p = 0.001) and a corresponding share of CHO for lunch, less for dinner (p = 0.015) and had a higher overall healthy diet score when compared to controls (p = 0.02). Adherence to dietary recommendations (e.g., CHO, total fats, saturated fat, fibers) was low in both genders, but lower in the general population compared to people with T1D. Conclusion: Our data demonstrate that people with T1D consume a healthier diet than the general population, which could be attributed to healthier diet awareness, still far from the recommendations. Introduction of annual consultations with a dietitian may improve long-term outcomes.

The impact of the COVID-19 pandemic on heart failure management: Global experience of the OPTIMIZE Heart Failure Care network.

During the COVID-19 pandemic, reductions in heart failure (HF) hospitalizations have been widely reported, and there is an urgent need to understand how HF care has been reorganized in countries with different infection levels, vaccination rates and healthcare services. The OPTIMIZE Heart Failure Care program has a global network of investigators in 42 countries, with first-hand experience of the impact of the pandemic on HF management in different care settings. The national coordinators were surveyed to assess: 1) the challenges of the COVID-19 pandemic for continuity of HF care, from both a hospital and patient perspective; 2) the organizational changes enacted to ensure continued HF care; and 3) lessons learned for the future of HF care. Contributions were obtained from 37 national coordinators in 29 countries. We summarize their input, highlighting the issues raised and using the example of three very different settings (Italy, Brazil, and Taiwan) to illustrate the similarities and differences across the OPTIMIZE program.

Circulating uncarboxylated matrix Gla protein in patients with atrial fibrillation or heart failure with preserved ejection fraction.

CONTEXT: Circulating uncarboxylated matrix Gla protein (ucMGP) is possibly related to coronary arterial calcification (CAC) in cardiovascular disease (CVD) patients. OBJECTIVE: We aimed to evaluate the relationships between circulating ucMGP, CVD pathology and CAC and its interplay with CVD risk factors. MATERIALS AND METHODS: ucMGP was measured in 99 CVD-patients. CAC score was determined by multislice computed tomography. Circulating ucMGP, uncarboxylated (ucOC) and carboxylated osteocalcin (cOC) were assayed by ELISA kits. Vitamin-K status was evaluated by ucOC/cOC ratio. RESULTS: A tendency for decreased ucMGP was observed for CAC ≥ 100 AU vs. CAC = 1-99 AU after exclusion of the patients on vitamin K-antagonist anticoagulants. Significant inverse correlations between ucMGP and vitamin-K status were indicated for the entire cohort and according to CAC score. Significant associations were found between ucMGP and risk factors for CVD. CONCLUSION: Circulating ucMGP may reflect certain stages of CVD and CAC. Future studies are needed to clarify its role as potential biomarker.

Navigating between Scylla and Charybdis: challenges and strategies for implementing guideline-directed medical therapy in heart failure with reduced ejection fraction.

Guideline-directed medical therapy (GDMT) has the potential to reduce the risks of mortality and hospitalisation in patients with heart failure (HF) with reduced ejection fraction (HFrEF). However, real-world data indicate that many patients with HFrEF do not receive optimised GDMT, which involves several different medications, many of which require up-titration to target doses. There are many challenges to implementing GDMT, the most important being patient-related factors (comorbidities, advanced age, frailty, cognitive impairment, poor adherence, low socioeconomic status), treatment-related factors (intolerance, side-effects) and healthcare-related factors that influence availability and accessibility of HF care. Accordingly, international disparities in resources for HF management and limited public reimbursement of GDMT, coupled with clinical inertia for treatment intensification combine to hinder efforts to provide GDMT. In this review paper, authors aim to provide solutions based on available evidence, practical experience, and expert consensus on how to utilise evolving strategies, novel medications, and patient profiling to allow the more comprehensive uptake of GDMT. Authors discuss professional education, motivation, and training, as well as patient empowerment for self-care as important tools to overcome clinical inertia and boost GDMT implementation. We provide evidence on how multidisciplinary care and institutional accreditation can be successfully used to increase prescription rates and adherence to GDMT. We consider the role of modern technologies in advancing professional and patient education and facilitating patient-provider communication. Finally, authors emphasise the role of novel drugs (especially sodium-glucose co-transporter 2 inhibitors), and a tailored approach to drug management as evolving strategies for the more successful implementation of GDMT.

Galectin-3 in patients with atrial fibrillation and restored sinus rhythm.

INTRODUCTION: Cardiac fibrosis is the hallmark of atrial remodeling in atrial fibrillation. Galectin-3 (Gal-3) is a biomarker of fibrosis. It is well studied in heart failure, but the data about its role in atrial fibrillation are sparse. AIM: The aim of the study was to evaluate the levels of Gal-3 in patients with atrial fibrillation after sinus rhythm restoration, to examine the association between this biomarker and other factors for developing atrial fibrillation and to assess its prognostic role. MATERIALS AND METHODS: We included 67 patients (35 male) at the mean age of 67.36±7.25 years, with Gal-3 test after sinus rhythm restoration, a subgroup of participants in placebo-controlled randomized clinical trial of treatment with spironolactone. They were followed up for atrial fibrillation recurrence and hospitalizations. The effect of demographic parameters and other factors on Gal-3 levels were evaluated before and one year after treatment. RESULTS: Mean Gal-3 at baseline was 16.9±6.8 ng/ml. Higher levels of Gal-3 were associated with female gender (р=0.008), increasing age (р=0.005), renal dysfunction (p<0.0001) and gout (р=0.002). Higher thromboembolic risk as assessed by CHA2DS2-VASc score was significantly related to Gal-3. The levels of biomarker did not affect the number of atrial fibrillation recurrences (p=0.9) and hospitalizations. No correlation was found with treatment with spironolactone, antiarrhythmic and antihypertensive drugs. CONCLUSIONS: Higher Gal-3 in atrial fibrillation was associated with female sex, renal dysfunction, and history of gout. The levels of Gal-3 were not related to rhythm control. Treatment with spironolactone did not affect the biomarker of fibrosis Gal-3 in AF patients. Higher Gal-3 was related to high embolic risk.

Vitamin D Status in Patients with Atrial Fibrillation and Heart Failure - Is there a Link?

BACKGROUND: The disturbed pleiotropic functions of vitamin D are related to numerous chronic non-skeletal diseases. The role of vitamin D insufficiency/deficiency in cardiovascular diseases (CVD) is controversial. Therefore, the aim was to study the vitamin D status in CVD patients and to reveal possible relationships with CVD risk factors. METHODS: This prospective study includes 93 individuals devided into two groups - patients with CVD (n = 49) and patients at risk for CVD (n = 44) served as controls. The CVD-patients were stratified into AF-group - with paroxysmal or persistent atrial fibrillation and HF-group - with heart failure with preserved ejection fraction, in sinus rhythm. Vitamin D status was assessed by measurement of serum 25-hydroxy-vitamin D (25OHD) using liquid chromatography with mass detection. Gene expression of the regulatory enzyme of vitamin D metabolism, 1-alfa-hydroxylase (CYP27B1), was evaluated by two-step real-time qPCR. Coronary artery calcium scans were performed and coronary artery calcium score (CACS) was calculated. Routine biochemical parameters were extracted from the medical documentation. Standard statistical methods (descriptive statistics, unpaired Student's t-test, one-way ANOVA, simple and multiple linear regression analyses) were applied. Statistical significance was considered at p < 0.05. RESULTS: Serum 25OHD levels of the controls were higher than those of the CVD-patients (37.36 ± 15.10 ng/mL vs. 27.70 ± 11.80 ng/mL, p = 0.008). The vitamin D status worsened with the severity of CVD pathology: significant decrease of 25OHD levels was found in the AF-group (29.56 ± 11.76 ng/mL, p = 0.044) and HF-group (24.47 ± 11.61 ng/mL, p = 0.003) vs. controls (37.36 ± 15.10 ng/mL). Significant reduction in circulating vitamin D levels with the increase of CACS (p = 0.007) was also observed. Linear regression analysis revealed significant negative association for serum 25OHD with CACS for both the entire studied group (p = 0.008) and for CVD patients (p = 0.049). The gene expression of CYP27B1 was down regulated with both the severity of CVD pathology (p = 0.05) and coronary calcium accumulation (p = 0.08). Moreover, we found a significant positive relationship (p = 0.041) between serum 25OHD levels and CYP27B1 gene expression. CONCLUSIONS: Vitamin D deficiency may be an independent cardiovascular risk factor associated with the severity of CVD pathology and increased coronary calcium deposition. The mechanism by which vitamin D itself can affect cardiovascular outcomes remains to be clarified.

Risk factors for recurrence of atrial fibrillation.

OBJECTIVE: Atrial fibrillation (AF) is a progressive disease, associated with increased risk of mortality, stroke, heart failure, and worsens quality of life. There is a high incidence of AF recurrence despite the treatment. The aim of the study was to assess the time to recurrence of AF after sinus rhythm restoration with electrical or pharmacological cardioversion and to identify the risk factors. METHODS: This study included 101 patients with AF (56% females) at a mean age of 68.02±7 years, after sinus rhythm restoration in a clinical observation of 1-year placebo-controlled treatment with spironolactone (1: 1). The patients were analyzed on the basis of AF recurrence, hospitalization, demographic parameters, comorbidities, embolic risk, and value of biomarker galectin-3 (Gal-3). RESULTS: The average number of AF recurrences was1.62 per patient per year. The median time of occurrence of at least one new episode was 48 days, 95% confidence interval (CI) 14.24-81.76. Female patients experienced significantly more recurrences than male-53.3% vs. 28.6% hazard ration (HR) =1.76, 95% CI 1.02-3.03, p=0.036. The recurrences were more common with increased age, although not significantly. Patients with arterial hypertension had a threefold risk of recurrences than those without hypertension (p=0.025), independently of the treatment. CHA2DS2-VASc score was significantly associated with AF recurrent episodes. Patients with gout had a twofold increased risk, without statistical significance (p=0.15). There was no difference in the AF episodes according to treatment with spironolactone. The levels of Gal-3 did not affect the number of AF recurrences (p=0.9). CONCLUSION: AF is associated with frequent recurrences after restoration of sinus rhythm in the majority of the patients. Most of them occurred within the first 3 months. Female sex, arterial hypertension, and CHA2DS2-VASc score were significant predictors of AF recurrence. Spironolactone did not reduce AF recurrences.

Statins, vascular calcification, and vitamin K-dependent proteins: Is there a relation?

The present cross-sectional clinical study aimed to examine the connection between statin exposure, coronary artery calcification (CAC), and vitamin K-dependent proteins (VKDPs) in patients with cardiovascular (CV) conditions. Two groups of patients were studied: patients with established CV disease (CVD) and healthy patients at moderate risk for CVD (a control group). The groups were also split into statin users and non-users. The following VKDPs were measured in plasma: uncarboxylated Matrix Gla-protein (ucMGP), undercarboxylated (ucOC), and carboxylated osteocalcin (cOC), Gla-rich protein (GRP). CAC score (CACS) was determined by multislice computed tomography. Among all the participants in the study, CACS was more pronounced in statin users compared to non-users; the same was found also among the CVD patients and among the controls. While the levels of ucMGP and GRP did not differ between statin users and non-users, ucOC and ucOC/cOC were significantly elevated in statin users, indicating vitamin K deficiency. There was a positive correlation between the levels of ucOC and CACS in the entire population and in the group of statin users, but not in statin non-users. No association was found between ucMGP or GRP and CACS. Statins had also an impact on the international normalized ratio and interacted with vitamin K antagonists (VKAs). Our results are in agreement with the existing evidence about positive association between statins and vascular calcification. They enlighten to a certain extent the possible mechanisms through which statins may enhance calcium accumulation in arterial wall, namely, by inhibition of vitamin K dependent proteins and functions involved in vascular protection.

Type 1 Diabetes Mellitus - Risk Factor for Cardiovascular Disease Morbidity and Mortality.

Type 1 diabetes mellitus (T1DM) is a chronic disease that starts early in life and often leads to micro- and macrovascular complications. The incidence of the disease is lower than that of type 2 DM and varies in different countries and ethnic groups, and the etiological and pathogenetic factors are different from T2DM. The aim of this overview is to investigate the effect of T1DM on all-cause mortality and CVD morbidity and mortality. During the last decades, the treatment of T1DM has improved the prognosis of the patients. Still, the mortality rates are higher than those of the age- and sex-matched general population. With the prolonged survival, the macrovascular complications and cardiovascular diseases (CVD) appear as major health problems in the management of patients with T1DM. The studies on the CVD morbidity and mortality in this disease group are sparse, but they reveal that T1DM is associated with at least 30% higher mortality. In comparison to healthy people, CVDs are more common in T1DM patients and they occur earlier in life. Furthermore, they are a major cause for death and impaired quality of life in T1DM patients. The correlation between diabetic control and the duration of T1DM is not always present or is insignificant. Nevertheless, the early detection of the preclinical stages of the diseases and the risk factors for their development is important; similarly, the efforts to improve glycemic and metabolic control are of paramount importance.

Dietary Intake and Adherence to the Recommendations for Healthy Eating in Patients With Type 1 Diabetes: A Narrative Review.

Background: Medical nutrition therapy is essential for all people with diabetes, of any type or severity. Compliance with the recommended nutrition is an integral part of the treatment of type 1 diabetes (T1D). It remains unclear to what extent the dietary intake of patients with type 1 diabetes adheres to the recommendations for healthy eating. Objective: The primary aim of our study is to collect and analyze published articles on the nutrition of T1D patients in comparison with the general population and recommendations. Research Strategy and Methods: A literature search for articles, published between January 2006 and July 2021 was conducted, using electronic databases (PubMed and Google Scholar) for all available publications in English and Bulgarian. The process of study selection, identification, screening, eligibility and inclusion followed the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) recommendations for a flowchart. Based on the keywords search, 425 titles were retrieved, of which 27 were selected based on title and abstract. All papers were crosschecked and reviewed for selection by 3 independent reviewers. As a result, 19 titles were eligible and met inclusion criteria for a full review. Results: Energy intake tends to be lower in T1D patients or comparable to controls and in most cases within the general recommendations. The percentage of calories from protein is within the recommendations for children, adolescents and adults. Only two studies showed that T1D patients consume significantly less than the recommendation for total fat intake (<35E%). The median intake of carbohydrates is in the lower end of the recommended 45 to 60E%. The median intake of dietary fiber adjusted for total energy is too low for T1D patients and the general population. Conclusion: Study findings suggested a lack of knowledge or misunderstanding of diabetes dietary management. Patients with T1D, who are being consulted with a dietician as a part of their treatment plan may have better compliance to their recommended diet and as a result, are likely to have better health outcomes. Nutritional therapy should focus not only on glycemic control and pure carbohydrate counting but also on healthy eating and complication prevention.

International Waist Circumference Percentile Cutoffs for Central Obesity in Children and Adolescents Aged 6 to 18 Years.

CONTEXT: No universal waist circumference (WC) percentile cutoffs used have been proposed for screening central obesity in children and adolescents. OBJECTIVE: To develop international WC percentile cutoffs for children and adolescents with normal weight based on data from 8 countries in different global regions and to examine the relation with cardiovascular risk. DESIGN AND SETTING: We used pooled data on WC in 113,453 children and adolescents (males 50.2%) aged 4 to 20 years from 8 countries in different regions (Bulgaria, China, Iran, Korea, Malaysia, Poland, Seychelles, and Switzerland). We calculated WC percentile cutoffs in samples including or excluding children with obesity, overweight, or underweight. WC percentiles were generated using the general additive model for location, scale, and shape (GAMLSS). We also estimated the predictive power of the WC 90th percentile cutoffs to predict cardiovascular risk using receiver operator characteristics curve analysis based on data from 3 countries that had available data (China, Iran, and Korea). We also examined which WC percentiles linked with WC cutoffs for central obesity in adults (at age of 18 years). MAIN OUTCOME MEASURE: WC measured based on recommendation by the World Health Organization. RESULTS: We validated the performance of the age- and sex-specific 90th percentile WC cutoffs calculated in children and adolescents (6-18 years of age) with normal weight (excluding youth with obesity, overweight, or underweight) by linking the percentile with cardiovascular risk (area under the curve [AUC]: 0.69 for boys; 0.63 for girls). In addition, WC percentile among normal weight children linked relatively well with established WC cutoffs for central obesity in adults (eg, AUC in US adolescents: 0.71 for boys; 0.68 for girls). CONCLUSION: The international WC cutoffs developed in this study could be useful to screen central obesity in children and adolescents aged 6 to 18 years and allow direct comparison of WC distributions between populations and over time.

Circulating proinflammatory peptides related to abdominal adiposity and cardiometabolic risk factors in healthy prepubertal children.

OBJECTIVES: To analyze the circulating levels of proinflammatory peptides in healthy prepubertal children in relation to abdominal obesity, measured by waist circumference (WC), and to investigate their interactions with cardiometabolic risk factors. DESIGN AND METHODS: A cross-sectional study of 137 healthy prepubertal children with a mean age of 8.0±0.1 years divided into three groups according to their WC as a measure of abdominal obesity: 'normal-WC' children (25th-75th percentile, n=48), 'children at risk' (75th-90th percentile, n=39), and 'abdominally obese' (≥90th percentile, n=50) children. Auxological measurements and blood pressure (BP) were taken. Fasting levels of high-sensitivity C-reactive protein (hsCRP), interleukin 6 (IL6), tumor necrosis factor-α (TNF-α), glucose, insulin, and lipid profile were measured. Insulin resistance (IR) was assessed by homeostasis model assessment of IR (HOMA-IR). RESULTS: Abdominally obese children had significantly higher BP, insulin, HOMA-IR, total cholesterol and triglycerides (TG) compared with their normal-WC counterparts (P<0.05). HsCRP concentrations increased proportionally with the degree of abdominal obesity (r=0.443, P<0.0001), whereas IL6 and TNF-α were not significantly associated with any of the adiposity variables. After controlling for adiposity, hsCRP was significantly correlated with systolic BP (r=0.257, P=0.004), TNF-α levels were related to high-density lipoprotein cholesterol (HDL-C; r=-0.216, P=0.016) and TG (r=0.196, P=0.029), whereas the relationship between IL6 and HDL-C reduced its magnitude to an insignificant level (r=-0.173, P=0.055). CONCLUSIONS: Healthy prepubertal children with abdominal obesity have associated inflammatory and cardiometabolic alterations, interacting with each other.

Waist circumference percentile curves for Bulgarian children and adolescents aged 6-18 years.

BACKGROUND: Waist circumference (WC) is a simple, easily available anthropometric measurement, giving relevant information about fat distribution and reflecting the degree of central adiposity in children. It appears to be the main risk factor for the progress of the metabolic syndrome. Our aim was to develop age- and sex-specific WC percentile curves for Bulgarian children/adolescents and to compare them with those from other countries. METHODS: A representative cross-sectional study of 3,810 healthy Bulgarian children/adolescents (2,052 males) aged 6-18 years, conducted in 2006/07. Body weight, height and WC were measured and body mass index (BMI) was calculated. Sex- and age-specific WC percentile curves were constructed using the LMS method. RESULTS: WC increased with age in both sexes (P<0.0001), with higher values in boys at every age and percentile point. This difference became significant from age 11 years onwards (P<0.05). The boys' values continued to increase steeply after this age, while in girls we found a constant continuing increase until the age of 15. Thereafter WC began to decrease and level off. The WC percentile values in Bulgarian children were lower than in US children, higher than in British and Turkish children, and similar to those of their Cypriot peers. CONCLUSIONS: For the first time, WC percentile curves were constructed for Bulgarian children/adolescents. A unique standardized method for WC measurement in children is needed for more acceptable international comparisons.