Małgorzata Krzywińska-Wiewiorowska

Establishing International Blood Pressure References Among Nonoverweight Children and Adolescents Aged 6 to 17 Years

Background— Several distributions of country-specific blood pressure (BP) percentiles by sex, age, and height for children and adolescents have been established worldwide. However, there are no globally unified BP references for defining elevated BP in children and adolescents, which limits international comparisons of the prevalence of pediatric elevated BP. We aimed to establish international BP references for children and adolescents by using 7 nationally representative data sets (China, India, Iran, Korea, Poland, Tunisia, and the United States). Methods and Results— Data on BP for 52 636 nonoverweight children and adolescents aged 6 to 19 years were obtained from 7 large nationally representative cross-sectional surveys in China, India, Iran, Korea, Poland, Tunisia, and the United States. BP values were obtained with certified mercury sphygmomanometers in all 7 countries by using standard procedures for BP measurement. Smoothed BP percentiles (50th, 90th, 95th, and 99th) by age and height were estimated by using the Generalized Additive Model for Location Scale and Shape model. BP values were similar between males and females until the age of 13 years and were higher in males than females thereafter. In comparison with the BP levels of the 90th and 95th percentiles of the US Fourth Report at median height, systolic BP of the corresponding percentiles of these international references was lower, whereas diastolic BP was similar. Conclusions— These international BP references will be a useful tool for international comparison of the prevalence of elevated BP in children and adolescents and may help to identify hypertensive youths in diverse populations.

Performance of Eleven Simplified Methods for the Identification of Elevated Blood Pressure in Children and Adolescents

The identification of elevated blood pressure (BP) in children and adolescents relies on complex percentile tables. The present study compares the performance of 11 simplified methods for assessing elevated or high BP in children and adolescents using individual-level data from 7 countries. Data on BP were available for a total of 58 899 children and adolescents aged 6 to 17 years from 7 national surveys in China, India, Iran, Korea, Poland, Tunisia, and the United States. Performance of the simplified methods for screening elevated or high BP was assessed with receiver operating characteristic curve (area under the curve), sensitivity, specificity, positive predictive value, and negative predictive value. When pooling individual data from the 7 countries, all 11 simplified methods performed well in screening high BP, with high area under the curve values (0.84–0.98), high sensitivity (0.69–1.00), high specificity (0.87–1.00), and high negative predictive values (≥0.98). However, positive predictive value was low for most simplified methods, but reached ≈0.90 for each of the 3 methods, including sex- and age-specific BP references (at the 95th percentile of height), the formula for BP references (at the 95th percentile of height), and the simplified method relying on a child’s absolute height. These findings were found independently of sex, age, and geographical location. Similar results were found for simplified methods for screening elevated BP. In conclusion, all 11 simplified methods performed well for identifying high or elevated BP in children and adolescents, but 3 methods performed best and may be most useful for screening purposes.

Environmental variation in the prevalence of hypertension in children and adolescents – is blood pressure higher in children and adolescents living in rural areas?

INTRODUCTION Despite considerable progress in diagnostic methods and treatment options, cardiovascular diseases constitute a serious health issue in Poland, and hypertension is considered one of the main risk factors in the incidence of the diseases. OBJECTIVES The aim of this study is to assess the values of arterial blood pressure among adolescents in the context of urban and rural environments. MATERIALS AND METHOD The study was carried out on a representative, randomly selected group of youths aged 10-18 years, participating in the ADOPOLNOR project. Prior to blood pressure measurement, each pupil was assessed according to anthropomorphic principles. The BP measurements strictly followed the guidelines of the Fourth Protocol of the American Working Group of High Blood pressure in Children and Adolescents. RESULTS Mean values of systolic blood pressure (SBP) in boys in rural areas were higher in every age group than in the boys in urban areas. Higher values of systolic and diastolic blood pressure were observed also in girls in rural areas. BP values sufficiently high for the diagnosis of hypertension were observed in 12.8% of the rural boy population but only in 6.7% of the boys from the urban environment. The difference is statistically significant. The girls in rural areas (13.3%) had twice the incidence of elevated BP values in comparison with the girls in urban areas (7.2%) and, as in boys, the difference is statistically significant. CONCLUSIONS The high proportion of pupils with elevated arterial blood pressure observed in the rural areas of Wielkopolska calls for regularly performed BP assessment and monitoring in this populatio.

Trends in the Incidence Rates of Chronic Hepatitis B in Poland in the Years 2005 - 2013.

Background The prevalence of newly-diagnosed cases of chronic hepatitis is decisive for the overall incidence rate of hepatitis B observed in Poland. Objectives We aimed to determine the chronic hepatitis B incidence trends in Poland, taking into consideration the ages, genders, and environments of the patients. Methods The study is based on aggregated data from Polish descriptive epidemiological studies for the period of 2005 to 2013 (i.e., hepatitis B incidence numbers and ratios, including mixed HBV and HCV infections) as published in the annual bulletins Choroby zakazne i zatrucia w Polsce (Infectious diseases and poisonings in Poland] drawn up by the laboratory for the monitoring and analysis of epidemiological status of the department of epidemiology at the national institute of public health - national institute of hygiene (NIPH-NIH). Poland, a central European country situated in the humid continental climate zone, is classified as a highly developed country. In the analyzed period, the Polish population consisted of about 38 million people, more than 19 million of whom were women, and more than 18 million of whom were men. Among European countries, Poland has the smallest number of national and ethnic minorities. For the purposes of epidemiological supervision, a special definition of acute hepatitis B was adopted in Poland in 2005, which facilitated separate registration of acute and chronic cases. Results A significantly increasing chronic hepatitis B incidence trend was observed in the population of Poland, with considerable increases in incidence rates for both men and women alike. The incidence rates for inhabitants of both urban and rural areas also showed an increasing tendency. Chronic hepatitis B occurred more frequently in men and in urban areas. For each of the five-year age groups encompassing patients between 20 and 54 years of age, the increase in the incidence rate proved to be significant. Conclusions The registered increase in the incidence rate of chronic hepatitis B in Poland is a consequence of the new registration of cases of chronic hepatitis B acquired in the past. The problem of chronic hepatitis B can be solved by improving epidemiological supervision, enhancing the detection of frequently asymptomatic infections, and by providing easier access to optimized therapies.

Malignant testicular tumour incidence and mortality trends

Aim of the study In Poland testicular tumours are the most frequent cancer among men aged 20–44 years. Testicular tumour incidence since the 1980s and 1990s has been diversified geographically, with an increased risk of mortality in Wielkopolska Province, which was highlighted at the turn of the 1980s and 1990s. The aim of the study was the comparative analysis of the tendencies in incidence and death rates due to malignant testicular tumours observed among men in Poland and in Wielkopolska Province. Material and methods Data from the National Cancer Registry were used for calculations. The incidence/mortality rates among men due to malignant testicular cancer as well as the tendencies in incidence/death ratio observed in Poland and Wielkopolska were established based on regression equation. The analysis was deepened by adopting the multiple linear regression model. A p-value < 0.05 was arbitrarily adopted as the criterion of statistical significance, and for multiple comparisons it was modified according to the Bonferroni adjustment to a value of p < 0.0028. Calculations were performed with the use of PQStat v1.4.8 package. Results The incidence of malignant testicular neoplasms observed among men in Poland and in Wielkopolska Province indicated a significant rising tendency. The multiple linear regression model confirmed that the year variable is a strong incidence forecast factor only within the territory of Poland. A corresponding analysis of mortality rates among men in Poland and in Wielkopolska Province did not show any statistically significant correlations. Conclusions Late diagnosis of Polish patients calls for undertaking appropriate educational activities that would facilitate earlier reporting of the patients, thus increasing their chances for recovery. Introducing preventive examinations in the regions of increased risk of testicular tumour may allow earlier diagnosis.