EFFECT OF IRON ON BONE TISSUE METABOLISM AND THYROID FUNCTION IN CHILDREN LIVING ON RADIOLOGICALLY CONTAMINATED TERRITORIES SINCE THE ChNPP ACCIDENT

OBJECTIVE

identification of clinical and metabolic characteristics of osteogenesis and factors affecting bone mineral density (BMD) in children living in radioactively contaminated territories (RCT) after the ChNPP accident for the use of therapeutic and preventive measures aiming to reduce the incidence of disorders.

MATERIALS AND METHODS

Children aged 4 to 18 years old (n = 539) were involved in the study within 4 age groups, namely under 7 years old, 7-10 years old, 10-14 years old, older than 14 years old. Studied parameters in children with a reduced BMD (85-65 relative units and under 65 relative units) were estimated vs. the normative BMD (100-85 relative units) cases. Diagnosis of osteopenia and osteoporosis in children was established according to the BMD T-index. Family history of the relatives of children was studied. Body weight at birth, fractures of the long bones, complaints of osalgia, jaw anomalies, dental caries, presence of obesity, and hypermobility syndrome (HMS) were assessed. Peripheral blood biochemical tests were performed featuring the serum total protein, alkaline phosphatase (APh), calcium, vitamin D, creatinine, serum iron (SI), ferritin, cortisol, pituitary thyroid-stimulating hormone (TSH), and free thyroxine (FT4) assay. BMD was measured and radiation doses in children were reconstructed.

RESULTS

BMD depended on the age of children. A direct correlation was established between the cholelithiasis and urolithiasis incidence (р < 0.01), cancer and endocrine diseases (р < 0.05) in the relatives of children that had BMD under 65 relative units. Dental caries developed more often (р < 0.05), while obesity was less frequent (р < 0.05) in the subjects with BMD < 65 relative units. A direct correlation was established between the level of serum creatinine and BMD (р < 0.01), and there was an inverse correlation between the serum APh level and BMD (р < 0.001).Every third child had a vitamin D deficiency. Fractures of long bones and increased content of SI and TSH were characteristic for the children having got osteopenia (BMD within 85-65 relative units), while besides a predisposition to bone fractures the higher levels of SI, APh, cortisol both with calcium deficiency were found in children with osteoporosis (BMD < 65 relative units) compared to the general group with a similar BMD. An increased incidence of HMS was characteristic too. Radiation doses in children with osteopenia were higher than in those with osteoporosis: (1.17 ± 0.09) mSv and (0.92 ± 0.06) mSv respectively (р < 0.05). No correlation was found between the radiation doses and clinical signs, blood biochemistry or BMD.

CONCLUSIONS

Study of the functional mechanisms of bone structures in children, depending on their metabolism, had made it possible to reveal the factors that affect bone formation in children living in RCT after the ChNPP accident, and to form the population groups for the timely application of therapeutic and preventive measures aiming to reduce the incidence of disorders of musculoskeletal system.

DRIVERS OF HYPERFERREMIA IN CHILDREN LIVING ON RADIOLOGICALLY CONTAMINATED TERRITORIES AFTER THE CHNPP ACCIDENT IN UKRAINE

OBJECTIVE

assessment of clinical-hematological and metabolic-biochemical parameters of the of bone tissue and hormonal regulation depending on the serum iron content and radiation dose values in children living on radiologically contaminated territories after the ChNPP accident in Ukraine.

MATERIALS AND METHODS

Children (n = 271) living on radiologically contaminated territories (RCT) of Ukraine were involved in the study. Three study groups were formed according to the serum iron level (SIL), namely group I with SIL 10.0-22.0 μmol/l (n = 92), group II with SIL 23.0-34.0 μmol/l (n = 144), and group III with SIL above 35.0 μmol/l (n = 35). Diseases in the family tree, bodyweight at birth, complaints on osalgia, bone fractures, jaw anomalies, dental caries, and obesity were accounted. Morphometric parameters of erythrocytes and hemogram elements were analyzed. Creatinine, alkaline phosphatase, calcium, total protein, iron, cholesterol, bilirubin, and transaminases were assayed in blood serum. The urine content of the 19 free amino acids, serum content of the free thyroxine (FT4), pituitary thyroid-stimulating hormone (TSH), and cortisol were assayed both with bone tissue density. Individual radiation doses were calculated.

RESULTS

In 12.9 % of cases the SIL was > 35.0 μmol/l. Relatives with endocrine diseases were often present in the family tree of children with SIL > 23.0 μmol/l. There were increased urine content of the free amino acids (p < 0.05) and signs of protein degradation under high SIL. Contents of amino acids involved in collagen synthesis and antioxidant status (alanine, serine, glutamine, aspartic acid) and iron metabolism (arginine, leucine) were assayed at the highest levels (p < 0.05). Urinary levels of valine, lysine, and methionine, which are associated with iron metabolism, were decreased (p < 0.05). An inverse correlation (rs = -0.58; p < 0.01) was established between the serum TSH and cortisol levels regardless of the SIL. Serum TSH level directly correlated with urine content of amino acids involved in collagen synthesis. An inverse correlation (rs = -0.55; p < 0.001) was established between the serum TSH level and urine content of tyrosine that is essential for the thyroid hormone (triiodothyronine and thyroxine) synthesis.Cortisol was found having a negative effect on protein synthesis. Inverse correlation was established between the serum cortisol level and urine content of the free amino acids essential for collagen synthesis. There was no dependence of the average radiation dose values on the SIL. An inverse correlation was determined between the patient's radiation dose and SIL > 35.0 μmol/l (rs = -0.29; p < 0.05).

CONCLUSIONS

The increased SIL in children living on RCT may occur due to both a genetic predisposition and the acquired factors driving protein and mineral metabolism of bone and their hormonal regulation.

FACTORS AFFECTING MECHANISMS OF INCREASED BONE DENSITY FORMATION IN CHILDREN LIVING ON RADIOLOGICALLY CONTAMINATED TERRITORIES AFTER THE ChNPP ACCIDENT

OBJECTIVE

to determine the causes of increased bone mineral density (BMD) based on case history, clinical and laboratory data, including the assay of hormones involved in ossification processes in children, living on radiologically contaminated territories (RCT) after the accident at the ChNPP, compared to the normative BMD patterns.

MATERIALS AND METHODS

There were 289 children involved in the study. The 1st group included persons with a BMD above 100 IU, 2nd group - with normative BMD (100-85 IU). Family history of diseases was assessed featuring cancer and endocrine diseases, cholelithiasis, and urolithiasis. Weight of the child at birth, frequency of bone fractures, complaints about osalgia, jaw abnormalities, dental caries, presence or absence of obesity, peripheral blood count, blood biochemical parameters (total protein, creatinine, iron, alkaline phosphatase, calcium), serum pituitary thyroid-stimulating hormone and cortisol were accounted. Children's radiation doses were calculated according to the materials of the «General dosimetric certification of settlements of Ukraine that were exposed to radioactive contamination after the Chornobyl accident».

RESULTS

Higher than normative BMD values were found in children after puberty, while normative ones - in puberty (р < 0.001), regardless of gender. A direct correlation between the bone fractures frequency was established in children with increased BMD (р < 0.01). Jaw anomalies and dental caries occurred at that significantly less often than in normative BMD (р > 0.05). A direct correlation was established between the obesity and BMD (р < 0.001).Increased alkaline phosphatase activity was inversely correlated with BMD (rs = -0.21; р < 0.05). In children with elevated BMD a direct correlation was established between the level of iron and endocrine disorders in the family history (р > 0.001). Serum level of cortisol was directly correlated with dental caries (р < 0.05). In children, regardless of BMD value, a direct correlation was established between the radiation dose, age and obesity (р < 0.001).

CONCLUSIONS

Higher than normative BMD is accompanied by an increased frequency of bone fractures, jaw abnormalities, metabolic changes in bone tissue and bone tissue hormonal regulation in children, which requires application of pathogenetic therapy for the osteogenesis.

EFFECT OF IRON ON BONE TISSUE METABOLISM AND THYROID FUNCTION IN CHILDREN LIVING ON RADIOLOGICALLY CONTAMINATED TERRITORIES SINCE THE ChNPP ACCIDENT

OBJECTIVE

To assess the metabolic processes in bone tissue and state of thyroid gland depending on iron metabolism parameters in children of pre-pubertal, pubertal and post-pubertal age, living on radiologically contaminated territories after the ChNPP accident.

MATERIALS AND METHODS

Children (n = 119) aged 6 to 18 years were examined and the 4 study groups were formed, featuring the childhood, pre-pubertal, pubertal and post-pubertal life periods. Clinical symptoms, iron metabolism parameters (serum iron (SI) and ferritin (SF) content, transferrin saturation coefficient), parameters of bone tissue metabolism (serum creatinine and alkaline phosphatase (APh)), and amino acid content in urine were taken into account. Functional state of thyroid, titers of antibodies to thyroperoxidase (TPOAb) and thyroglobulin (TgAb) were assayed. Results and their discussion are presented depending on the age of children, biochemical parameters of blood, iron metabolism findings, thyroid gland function and individualized radiation doses.

RESULTS

In 13.4 % of pubertal and post-pubertal children an elevated content of SI and SF was observed. APh levels were increased in 20.2 % of children (758.9 ± 16.3 U/l) being directly correlated with SI levels (rs = 0.50; р < 0.01). In 16.3 % of children of pubertal and post-pubertal age, in whom the level of SI was above 27 μmol/l, a direct correlation with serum thyroid-stimulating hormone (TSH) level was established in case of the hormone content above 2.5 mU/l (rs = 0.50; р < 0.05). Serum creatinine level directly correlated with glycine content in urine (rs = 0.70), which is a part of collagen, and inversely correlated with serum APh (rs = -0.47), (р < 0.05). Under the levels of SI higher than (15.1 ± 1.2) μmol/l and SF higher than (87.5 ± 6.4) ng/ml, the TPOAb titer was higher than at lower iron concentrations (U-test = 64.5, р < 0.05). The TgAb titer directly correlated with SI (rs = 0.39) and TSH (rs = 0.81) levels (р < 0.01). The average effective radiation dose in children was (0.75 ± 0.10) mSv. A direct correlation was established between the child's radiation dose and age (rs = 0.33; р < 0.05).

CONCLUSIONS

Bone metabolism depends on the age of children, characteristics of pubertal period, excess of iron in the body, and functional state of thyroid system, which is involved in collagen formation and protein metabolism.

CLINICAL-METABOLIC AND HORMONAL RELATIONSHIPS BETWEEN PARATHYROID DISEASE AND OTHER NON-CANCEROUS ENDOCRINE DISORDERS IN THE CHORNOBYL NPP ACCIDENT SURVIVORS

OBJECTIVE

to investigate the clinical, hormonal-metabolic and structural features of parathyroid injuries in sur-vivors exposed to ionizing radiation after the Chornobyl NPP accident in adulthood and childhood, both with theirconnections to other non-cancerous endocrine disorders, and to establish the respective interhormonal and dys-metabolic relationships.

MATERIALS AND METHODS

Clinical effects of ionizing radiation on the endocrine system in persons affected by theChornobyl NPP accident (n = 224) and their descendants (n = 146), compared with the general population sample(n = 70) were the study object. All patients underwent the ultrasound thyroid and parathyroid examination. Thegenerally recognized clinical, anthropometric (body weight, height, thigh volume, body mass index), instrumental(ultrasound examination of thyroid and parathyroid glands), laboratory (biochemical, hormonal), and statisticalmethods were applied. Parametric and nonparametric statistical methods were used in data processing. The value ofp < 0.05 was considered a statistically significant.

RESULTS

No significant difference was found in the incidence of carbohydrate metabolic disorders in the ChornobylNPP (ChNPP) accident consequences clean-up workers (ACCUW), evacuees from the NPP 30-km exclusion zone, res-idents of radiologically contaminated areas and in the control group in whom the parathyroid hyperplasia wasdetected. There was a significant increase in the incidence of arterial hypertension among ACCUW who had parathy-roid hyperplasia (76.9%) vs. the control group (51.2%). In cases of parathyoid hyperplasia the vitamin D levels weresignificantly lower than without it. Vitamin D insufficiency/deficiency was found in 94% of the surveyed subjects.The average level of parathyroid hormone in blood serum was significantly higher in the ACCUW of «iodine» period withdiagnosed parathyroid hyperplasia than in the control group: (57.2 ± 2.87) pg / ml against (32.74 ± 3.58) pg / ml,p < 0.05. Results of multivariative analysis indicated a strong association of vitamin 25(OH)D insufficiency/defi-ciency with development of thyroid disease, carbohydrate metabolic disorders, cardiovascular disease, osteo-penia/osteoporosis. parathyroid ultrasound scan was at that an effective diagnostic method for primary screeningfor parathyroid hyperplasia and regular monitoring of the treatment efficiency. When examining children bornto parents irradiated after the ChNPPA the parathyroid hyperplasia (58%) and low serum content of vitamin D(11.6 ± 3.5) nmol / l were most often found in children living on radiologically contaminated territories (RCT).A strong correlation was established between the HOMA insulin resistance index and serum content of vitamin D(r = 0.65), parathyroid hormone (r = 0.60), and free thyroxine (r = 0.68) in the group of children born to parents irra-diated after the ChNPPA, having got chronic autoimmune thyroiditis, which indicated a relationship between thy-roid function, impaired carbohydrate and fat metabolism and the state of parathyroids.

CONCLUSIONS

No difference in the incidence of carbohydrate metabolic disorders was found in the ChNPP ACCUW,evacuees from the 30-km exclusion zone, and residents of radiologically contaminated territories in whom parathy-roid hyperplasia was detected vs. the control group. Patients with parathyroid hyperplasia were found to be defi-cient in vitamin D in 94% of cases, and level of latter was significantly lower than under the normal parathyroid size.There was a significant increase in the incidence of diagnosed arterial hypertension among ACCUW who had parathy-roid hyperplasia vs. the control group: (76.9 ± 3.5)% vs. (51.2 ± 3.7)%. According to multivariate analysis a strongassociation between the vitamin 25(OH)D insufficiency/deficiency and development of thyroid disease, carbohydratemetabolic disorders, cardiovascular disease, and osteopenia/osteoporosis was established. The average level of pa-rathyroid hormone in the blood serum of the ChNPP ACCUW of the «iodine» period with diagnosed parathyroid hyper-plasia was significantly higher (57.2 ± 2.87) pg / ml against (32.74 ± 3.58) pg / ml; p <0,05) in the control group.

DENTAL CARIES INTENSITY IN CHILDREN WITH DISTURBANCES IN TOOTH FORMATION, SURVIVED AFTER THE CHORNOBYL NPP ACCIDENT

OBJECTIVE

assessment of dental caries intensity in children with disturbances in tooth formation living in radiologically contaminated territories as a result of the Chornobyl NPP accident.

MATERIALS AND METHODS

Children aged 6-14 years old (n = 1470) suffering from disturbances in tooth formation(DTF) with the residents of radiologically contaminated territories (n = 528) among them were enrolled in the study.The DTF subtypes were assayed, namely the systemic enamel hypoplasia (SEH) and molar incisor hypomineralisation(MIH). Personal radiation history was recorded. Intensity of caries and caries of surfaces in the mixed (i.e. transitional) occlusion (df+DMF, dfs+DMFS coefficients) and permanent occlusion (DMF, DMFS coefficients) was identified.

RESULTS

Caries intensity in the exposed children suffering DTF with mixed and permanent dental occlusion was sig-nificantly higher vs. either in children exposed to ionizing radiation with no DTF or in the control group (р < 0.001,р < 0.001 and р < 0.05, р < 0.001 correspondingly). The highest caries intensity of the permanent teeth was revealedin the residents of contaminated territories suffering SEH (6.95 ± 2.3) vs. cases of MIH (5.68 ± 1.97) as a result ofnonsymmetrical teeth involvement.

CONCLUSIONS

The highest values of df+DMF, dfs+DMFS coefficients were diagnosed in children with a mixed dentalocclusion aged 6-14 years old living on territories contaminated as a result of the ChNPP accident as compared tothe not exposed subjects and control group (7.2 ± 2.07 and 8.98 ± 2.4, р < 0.001). A very high intensity of cariesand surface caries of permanent teeth (DMF = 6.79 ± 2.34, DMFS = 8.69 ± 2.75, р < 0.001) was established in children exposed to ionizing radiation and suffering DTF. Such a high intensity may be due to the impact of a set of negative factors including the ionizing radiation in low doses and peculiarities of economic component of social sta-tus of study subjects, namely the unbalanced diet. In case of permanent occlusion the intensity of caries and cariesof tooth of in children survived after the ChNPP accident and suffering SEH was significantly (р < 0.05) higher compared to the persons suffering MIH.

ENDOCRINE REGULATION OF ERYTHROID LINEAGE OF HEMATOPOIESIS IN CHILDREN LIVING UNDER A LOW-DOSE RADIATION EXPOSURE AFTER THE CHORNOBYL NPP ACCIDENT

OBJECTIVE

Elucidation of relationship between the levels of thyroid-stimulating hormone (TSH), free serum thyroxine, serum and urine cortisol and parameters of erythroid lineage of hematopoiesis to estimate the thyroid functionin children of prepubertal, pubertal, and postpubertal age permanently residing under a low-dose radiation exposureto determine the premorbid state of thyroid function.

MATERIALS AND METHODS

Children aged 3 to 18 years old (n = 203) living in the most intensively radionuclide-contaminated regions of Kyiv, Zhytomyr and Chornihiv oblasts of Ukraine after the Chornobyl NPP accident wereenrolled. Complaints of ossalgia, arthralgia, fatigue, bone fractures in the history, bone dysembryogenetic stigmata,hypermobility syndrome degree, and types of somatic diseases were taken into account. Peripheral blood countparameters, biochemical indices of blood serum were studied, namely the levels of total protein, cholesterol, creatinine and alkaline phosphatase activity. Levels of the free thyroxine, pituitary TSH, serum and daily urine cortisol, anddoses of radiation exposure were determined.

RESULTS

The radiation dose values in children ranged from (0.35 ± 0.09) mSv to (0.54 ± 0.12) mSv. There was nodifference between the parameters of erythroid lineage of hematopoiesis depending on radiation dose. At the levels of serum TSH up to 1.0 μIU/ml no correlation was found with cortisol levels; at TSH levels of 1.0-3.0 μIU/ml thecorrelation coefficient was r = 0.31; at TSH levels higher than 3.0 μIU/ml the correlation coefficient was r = 0.61probably indicating a compensatory role of adrenal cortex in children at risk of thyroid disease development. In children with joint hypermobility grade II there was a higher incidence of dentofacial anomalies (χ2 = 6.9), deformitiesof lower extremities (χ2 = 6.9), and dental caries (χ2 = 4.3) (p < 0.05). There was a direct correlation between theserum TSH level (over 3 μIU/ml) and micrognathia (brachygnathia) (r = 0.62) indicating the impact of thyroid disease on dentofacial development. The TSH at a level of upper limit of the reference range values may contribute toa decreased RBC count in peripheral blood, increased average volume and hemoglobin content in erythrocyte beingassociated with the initial manifestations of thyroid dysfunction.

CONCLUSIONS

Abnormal endocrine regulation of hematopoiesis affects the connective tissue, stromal microenvironment of bone marrow, and accordingly the erythroid branch of hematopoiesis in children, which may be relevant inthe development and course of oncohematological diseases.

[HYPERPARATHYROIDISM AND PARATHYROID LESIONS IN THE ChNPP ACCIDENT SURVIVORS]

OBJECTIVE

Study of the status of parathyroid glands in individuals exposed to ionizing radiation as a result of the ChNPP accident and comparison with the general population of Ukraine.

MATERIALS AND METHODS

Subjects exposed as a result of the ChNPP accident (n = 1,348) and people from the general population of Ukraine (n=655) were examined. Diagnostic ultrasound scan of thyroid and parathyroid glands (PTG) was conducted in all study subjects. The technique of parathyroid ultrasound screening was developed, which led to an increase in the efficiency of their imaging. Additionally, the 25-hydroxyvitamin D (25(OH)D), parathyroid hor- mone, ionized calcium and some other parameters were selectively assayed in serum.

RESULTS

High incidence of parathyroid hyperplasia was detected 27-32 years after the irradiation in persons ex- posed as a result of the ChNPP accident, especially in evacuees from the 30-km exclusion zone (71.4%; χ2Yates' = 24.1; р = 0) and residents of radilogically contaminated territories (41.7%; χ2Yates' = 6.45; p < 0.01) having no primary hyperparathyroidism. High prevalence of vitamin D insufficiency and deficiency was revealed in all study subgroups, namely in 83.1 % of the general population of Ukraine along with a bit better vitamin D status in the ChNPP acci- dent survivors i.e. the vitamin insufficiency and deficiency was found in 78.7 % of them. Incidence of hyperparathy- roidism, predominantly of the secondary (normocalcemic) one, was 33.8 % among persons exposed as a result of the ChNPP accident (p > 0.3) being somewhat higher than in the general population of Ukraine (26.1%), despite above- mentioned better supply of vitamin D.

CONCLUSIONS

There is a widespread insufficiency or deficiency of vitamin D (over 78.7%) in the population of Ukraine in general providing an unfavorable background for the higher prevalence of health disorders associated with calcium and phosphorus metabolism. The latter features parathyroid hyperplasia and musculosceletal, immune, cardiovascular, and endocrine system comorbidities. Such disorders should exacerbate with a secondary increase in parathyroid hormone secretion (26.1 %). Higher incidence of normocalcemic hyperparathyroidism (33.8% versus 26.1%) against a background of better vitamin D status among irradiated individuals indicates the existence of other factors, where the past combined effects of Chornobyl radioactive fallout and external parathyroid exposure are most likely to be involved. This could explain the greater number of cases of parathyroid hyperplasia and hyper- parathyroidism among the exposed subjects. However the additional precise studies are required here with clarifi- cation of the personal data in population groups of the ChNPP accident survivors. Participants of the ChNPP acci- dent clean-up work in the «iodine period» of 1986 are of especial concern here. Besides that, the study population should be expanded with inclusion of subjects exposed in prenatal period.

PROGNOSIS OF THE COURSE OF CHORNOBYL-ORIGINATED ACUTE LYMPHOBLASTIC LEUKEMIA IN CHILDREN IN UKRAINE DEPENDING ON THE REASON OF STANDARD CHEMOTHERAPY INTERRUPTION

OBJECTIVE

Estimation of the bone marrow haemopoietic status depending on the reasons and duration of breaks in a standard chemotherapy (BFM-ALL protocol) to predict the course of acute lymphoblastic leukemia (ALL) in chil- dren exposed to low doses of ionizing radiation after the Chornobyl accident.

MATERIALS AND METHODS

The ALL patients (n = 34) were examined within 5 stages of a program chemotherapy. The clinical symptoms, hemogram and myelogram data were analyzed. The radiation dose on bone marrow, initial leuko- cyte count, variants and prognosis of ALL course were accounted. Days of the stopped chemotherapy, type and fre- quency of complications (septic processes, febrile neutropenia, toxic hepatitis, granulocytopenia degree), and the prognosis of disease course (child living status, i.e. alive or died) were estimated.

RESULTS

There were abnormal differentiation processes and high percentage of lymphoblasts (86.2 ± 3.3) % in bone marrow in the 1st acute period. Hematological remission was established in all patients on the 33rd day of chemothe- rapy. In a half of cases the haematopoietic recovery occurred by a granulocyte-monocyte type. One third of patients presenting an erythroid type of haemopoiesis died later. The inverse correlation was found between the number of myelocaryocytes and disease prognosis (rs = -0.49). Breaks in chemotherapy for various reasons were recorded. The number of patients with granulocytopenia was greater at the phase 1 and 2 of protocol I and protocol M application, coinciding with a higher incidence of complications. An inverse correlations between the prediction of ALL course and sum of days of breaks between the protocol M and phase 1 of protocol II (rs = -0.56), as well as the duration of the phase 2 of protocol II (rs = -0.62) were found. The radiation dose on bone marrow was (5.37 ± 1.23) mSv. No relationship was found between the radiation doses, ALL variants and disease course.

CONCLUSIONS

Prognosis of ALL course in children depends on the type of haemopoietic recovery and reasons of breaks in a standard chemotherapy. Interaction between the haemopoiesis functioning and microenvironment and that of their regulation are the key mechanisms of above-mentioned abnormalities, which is the basis for further research.

ORAL HYGIENE IN CHILDREN WITH DISTURBANCES IN TOOTH FORMATION WHO WERE AFFECTED AS A CONSEQUENCE OF THE ChNPP ACCIDENT

OBJECTIVE

evaluation of oral hygiene to enhance the prophylaxis of complications specifically of dental caries inchildren with disturbances in tooth formation (DTF) who live on radiologically contaminated territories after theChornobyl NPP (ChNPP) accident.

MATERIALS AND METHODS

Children aged 6-14 years (n = 1470) with DTF were the study subjects examined in 2012-2016. Among them there were (n = 528) residents of the zones III and IV of radiological contamination after theChNPP accident with 137Cs soil contamination density 1-15 Ci/km2. The effective radiation dose in them was notexceeding 1 mSv/year. The Green-Vermillion and Silness-Loe oral hygiene indices were assesses within clinicalexamination methods.

RESULTS

The worth oral hygiene was revealed in children having got the DTF, compensated chronic diseases oforgans and systems, and in those with burdened radiation history. The Green-Vermilion and Silness-Loe indices were1.7 ± 0.51 and 1.65 ± 0.46 respectively.

CONCLUSIONS

A significant deterioration in oral hygiene confirmed by the highest values of the Green-Vermillion index (1.7 ± 0.51; p < 0.001 - «unsatisfactory oral hygiene» criterion) and Silness-Loe index (1.65 ± 0.46; p < 0.001 -«poor oral hygiene» criterion) was found in children with DTF aged 6-14 years being residents of contaminated areasas a result of the Chernobyl accident. The revealed deterioration may be due to a set of negative factors, includingthe impact of ionizing radiation in low doses and peculiarities of social status. Results of the questioning of surveyed pediatric contingents both having got an DTF and with no defects of the hard tissues of teeth indicate aninsufficient level of knowledge and skills in hygienic care of oral cavity regardless of the area of residence.Development of a set of measures to prevent the DTF complications in children should be carried out taking intoaccount the state of oral hygiene, level of knowledge and skills in oral care, and include the use of hygiene products, namely toothpastes and anti-caries mouthwashes.

Structural characteristics of children and adolescents at the time of the Chornobyl nuclear power plant accident residing in the most intensively contaminated territories of Ukraine

OBJECTIVE

Appraisal of trends in structure of characteristics in population of radiologically contaminated territo ries (RCT) born in 1968-1986 (children and adolescents at the time of the ChNPP accident).Study Object. Persons born since 1968 till 1986 i.e. children and adolescents at the time of the ChNPP accident, who lived on the most intensively contaminated territories of Ukraine (Ivankiv and Poliske regions of Kyiv oblast and Narodichi and Ovruch regions of Zhytomyr oblast) within 1986-2011.

MATERIALS AND METHODS

The State Service of Statistics of Ukraine was a principal information base of the study. Specifically the statistical report forms R 11 «Distribution of residential population by gender and age in yearly intervals at a turn of the year» and A 1 «General totals of natural population development» were retrieved. Survey was conducted for the period of 1986-2012. Mathematical, statistical, demographic and software technological methods were applied.

RESULTS AND CONCLUSIONS

Summarization of statistical data on population size, both with its gender and age pat terns in the most intensively contaminated territories of Ukraine, namely in Ivankiv and Poliske regions of Kyiv oblast and Narodichi and Ovruch regions of Zhytomyr oblast resulted in conclusion of 27,200 people living there who were born in 1968-1986. They are a critical group of the ChNPP accident survivors. At the beginning of 1987 the male generations of the same age were present in more even manner (4.53-5.82 %%) vs. females (3.04 6.02 %%). No significant change both in gender and year of birth was found in 2012 vs. 1987. Change in gender proportion in surveyed population within 1986 2011 requires some more precise evaluation.

Non cancer thyroid and other endocrine disease in children and adults exposed to ionizing radiation after the ChNPP accident

STUDY OBJECTIVE

To summarize the verified clinical and epidemiological data on the natural history of non cancer endocrine disease in remote period after the ChNPP accident in survivors of adult and children age.

MATERIALS AND METHODS

Retrospective estimation was carried out of data on 24,588 adult persons and 20,087 chil dren survived after the ChNNP accident and being healthy or having any diseases. Data were retrieved from database of the Clinical Epidemiological Registry (CER), NRCRM for the 23 years (1992-2014) of survey. Average total external radiation dose in adults was 0.187 Gy, range of thyroid dose in children was 0.1-1.55 Gy. These data were verifies in a separate clinical study. Anthropometric, laboratory biochemical and hormonal assay values, thyroid ultrasound imaging patterns and radiation dose values were retrieved for the study.

RESULTS

Retrospective data review for the 1992-2014 period indicated that incidence of thyroid disease in all per sons survived after the ChNPP accident run at 40.29% with 35.37% among the clean up workers, 27.24% among evac uees, and 28.6% among population of contaminated territories that all is significantly (p < 0.0001) higher vs. the entire population of Ukraine (3.9%). Following non cancer endocrine diseases were most prevalent in the ChNPP acci dent survivors: nodular goiter (14.35%), chronic autoimmune thyroiditis (~8%), pre obesity and obesity (41.9% and 36.8% respectively), prediabetes and diabetes mellitus (15.5% and 21.4% respectively). Nodular goiter (21.8%), chronic autoimmune thyroiditis (12.95%), pre obesity and obesity (41.71% and 33.61% respectively), and predia betes and diabetes mellitus (8.6% and 12.15% respectively) were most often diagnosed in the ChNPP accident clean up workers. Children evacuated from the 30 kilometer exclusion zone were a critical population group. They were diagnosed diffuse non toxic goiter in 43.68%, chronic autoimmune thyroiditis in 1.74%, primary hypothyroidism in 0.96%, and nodular goiter in 2.57%. Peak prevalence of chronic autoimmune thyroiditis occurred in 2001-2003 i.e. in a period of their intensive pubertal maturation. In children (first generation) of exposed parents the thyroid dis ease was revealed in 42.64%, that exceeded the incidence in control group, chronic autoimmune thyroiditis was found rarer i.e. in 0.45%, diffuse non toxic goiter in 9.5-13.8%, nodular goiter in 1.7%.

CONCLUSIONS

Non cancer endocrine disease in children and adults exposed to ionizing radiation is frequent and reg istered in 3 53% of persons. It occurs in most of survivors 10-15 years upon the impact of radiation factor as a result of man made accident and continues to grow slowly in 30 years.

Peculiarities of non-malignant endocrine disease in the Chornobyl NPP accident survivors, and hormonal interaction role

Study objective. Identification of the role of intersystemic hormonal interactions in development of most prevalent central and peripheral non-malignant clinical/metabolic endocrine disorders in the Chornobyl NPP accident (ChNPPA) survivors. Materials and methods. Retrospective assay of non-malignant radiation effects on endocrine system was applied in 18,192 survivors of the ChNPPA. Data from the Clinical/Epidemiological Register of the SI "National Research Center for Radiation Medicine of the National Academy of Medical Sciences of Ukraine" for the period of 1993-2003 were involved. Anthropometric values, biochemical and hormonal assay indices, diagnostic thyroid ultrasound data, external radiation dose values were taken into account both with calculated insulin resistance index. Results. Thyroid disease incidence in ChNPPA survivors increased dramatically 10 years upon radiation impact being 39.33 % in average, 14.35 % (р < 0.01 vs. entire population) for nodular goiter, and about 8 % for autoimmune thyroiditis (р < 0.01 vs. the same). As a result of an advanced examination of ChNPPA survivors the incidence of diffuse non-toxic goiter was 40.4 % (χ2Yates = 73.82; р = 0), of nodular goiter - 23.1 % (χ2Yates = 14.13; р = 0.002) vs. values in the control group (4.8 % and 17.6 % respectively). Some hormonal interactions were identified in study subjects indicating the thyroid disease onset under radiation impact through insulin resistance at the background of adipose tissue excess followed by body mass index increase, elevation of serum C-peptide and leptin levels, and onset of lipid metabolic disorders. Conclusions. Significant increase of the incidence of thyroid disease (1.5-3-fold), diabetes mellitus (3-7-fold), pre-obesity and obesity (in 25.67 %), and metabolic syndrome (5-fold) vs. entire population of Ukraine was found in remote terms upon the accident. Intricate pathogenetic intersystemic hormonal interactions were identified predisposing to thyroid disease due to insulin resistance, accompanying hyperinsulinemia, increased body mass index and some other hormonal and biochemical factors.

Morbidity pattern of non-cancer endocrine disease in ChNPP accident emergency workers (1992-2013 Clinical/Epidemiological Registry data)

Objective. The study examined the morbidity pattern of non-cancer endocrine disease in ChNPP accident emergency workers (AEW) versus the entire population of Ukraine. Materials and methods. The study included a retrospective estimation of the examination data from 10,771 ChNPP AEW of the so-called iodine and non-iodine periods (main study group). Data were received from the RCRM Clinical/Epidemiological Registry for the survey period of 22 years (1992-2013) on persons been either healthy or having a range of endocrine disease. Anthropometric measures both with biochemical and hormonal assay data and external radiation dose values were taken into account. Diagnostic thyroid ultrasound was applied. Results. There is a significant (2-10-fold) and reliable (p < 0.01) increase of the incidence of non-cancer endocrine disease in the ChNPP AEW, namely by 23.20 % of nodular goiter (0.53 % in control, χ2 = 9602, р < 0.0001), by 13.37 % of autoimmune thyroiditis (0.35 % in control; χ2 = 5381, р < 0.0001), by 11.89 % in average and by 16.29 % in last years of type 2 diabetes mellitus (χ2 = 2527, р < 0.0001), by 41.67 % of pre-obesity (χ2 = 10.92, р < 0.01), and by 38.12 % of obesity (χ2 = 41.50, р < 0.01) compared to the entire population. Conclusions. Effects of ionizing radiation and other hazardous factors on endocrine system in the ChNPP AEW appeared upon 15-25 years. There was a significant (2-10-fold) and reliable (p < 0.01) increase of the incidence of the nodular goiter, autoimmune thyroiditis, obesity, type 2 diabetes mellitus. And there is a trend to further increase.