Community Noise Exposure and its Effect on Blood Pressure and Renal Function in Patients with Hypertension and Cardiovascular Disease.

BACKGROUND: Road traffic noise (RTN) is a risk factor for cardiovascular disease (CVD) and hypertension; however, few studies have looked into its association with blood pressure (BP) and renal function in patients with prior CVD. AIM: This study aimed to explore the effect of residential RTN exposure on BP and renal function in patients with CVD from Plovdiv Province. MATERIALS AND METHODS: We included 217 patients with ischemic heart disease and/or hypertension from three tertiary hospitals in the city of Plovdiv (March - May 2016). Patients' medical history, medical documentation, and medication regimen were reviewed, and blood pressure and anthropometric measurements were taken. Blood samples were analyzed for creatinine, total cholesterol, and blood glucose. Participants also filled a questionnaire. Glomerular filtration rate was estimated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. All participants were asked about their annoyance by different noise sources at home, and those living in the city of Plovdiv (n = 132) were assigned noise map Lden and Lnight exposure. The effects of noise exposure on systolic blood pressure (SBP), diastolic blood pressure (DBP), and estimated glomerular filtration rate (eGFR) were explored using mixed linear models. RESULTS: Traffic noise annoyance was associated with higher SBP in the total sample. The other noise indicators were associated with non-significant elevation in SBP and reduction in eGFR. The effect of Lden was more pronounced in patients with prior ischemic heart disease/stroke, diabetes, obesity, not taking Ca-channel blockers, and using solid fuel/gas at home. Lnight had stronger effect among those not taking statins, sleeping in a bedroom with noisy façade, having a living room with quiet façade, and spending more time at home. The increase in Lden was associated with a significant decrease in eGFR among men, patients with ischemic heart disease/stroke, and those exposed to lower air pollution. Regarding Lnight, there was significant effect modification by gender, diabetes, obesity, and time spent at home. In some subgroups, the effect of RTN was statistically significant. CONCLUSIONS: Given that generic risk factors for poor progression of cardiovascular diseases cannot be controlled sufficiently at individual level, environmental interventions to reduce residential noise exposure might result in some improvement in the management of blood pressure and kidney function in patients with CVD.

Association between community noise and adiposity in patients with cardiovascular disease.

INTRODUCTION: This study aimed to explore the effect of community noise on body mass index (BMI) and waist circumference (WC) in patients with cardiovascular disease (CVD). MATERIALS AND METHODS: A representative sample of 132 patients from three tertiary hospitals in the city of Plovdiv, Bulgaria was collected. Anthropometric measurements were linked to global noise annoyance (GNA) based on different residential noise annoyances, day-evening-night (Lden), and nighttime (Lnight) road traffic noise exposure. Noise map Lden and Lnight were determined at the living room and bedroom façades, respectively, and further corrected to indoor exposure based on the window-opening frequency and soundproofing insulation. RESULTS AND DISCUSSION: Results showed that BMI and WC increased (non-significantly) per 5 dB. The effect of indoor noise was stronger in comparison with that of outdoor noise. For indoor Lden, the effect was more pronounced in men, those with diabetes, family history of diabetes, high noise sensitivity, using solid fuel/gas for domestic heating/cooking, and living on the first floor. As regards indoor Lnight, its effect was more pronounced in those with low socioeconomic status, hearing loss, and using solid fuel/gas for domestic heating/cooking. GNA was associated with lower BMI and WC. CONCLUSION: Road traffic noise was associated with an increase in adiposity in some potentially vulnerable patients with CVD.

Effect of Nitrates, Thiocyanates and Selenium on the Iron and Iodine Status of Postpartum Women.

AIM: To find correlations between high thiocyanate and nitrate levels and low selenium levels and the indicators of the iodine and iron status of postpartum women. MATERIALS AND METHODS: The study included 41 mothers aged 26.4±5.9 yrs from Asenovgrad and nearby villages. Urinary iodine was determined by the Sandell-Kolthoff reaction and thiocyanate - by the interaction of these ions with acidic solution of KMnO4; for serum nitrates we used the colorimetric method; serum selenium was assessed by electro-thermal atomic-absorption spectrophotometry; thyroxin (FT4), the thyroid stimulating hormone (TSH), serum ferritin (SF), and serum transferrin receptor (sTfR) were determined using ELISA; Hb levels were determined by hematology analyzer. RESULTS: Assessing the iodine status, we found a negative correlation between the levels of iodine and thiocyanates in urine (R=-0.717, р<0.0001), a positive correlation between nitrates and TSH (R=0.487, р=0.003) and a negative correlation between nitrates and FT4 (R=-0.312, р=0.06). For the iron status, we found a negative correlation between nitrates and SF (R=-0.429, р=0.009) and between nitrates and Hb (R=-0.383, р=0.021). The Mann-Whitney U-test showed that in women with nitrate levels higher than the mean value there was low FT4 level (р=0.06), high TSH level (р=0.013), low Hb concentration (р=0.061) and low SF concentration (р=0.005). The combined effects of environmental factors (elevated nitrate levels and low selenium level) on the iodine and iron status are manifested by low concentrations of FT4 (р=0.033), Hb (р=0.06) and SF (р=0.05) and high level of TSH (р=0.05). In conclusion, we found that environmental factors, especially when combined, have a negative impact on the iron and iodine status of females.

The Role of Eating Habits on the Iron Status of Pregnant Women.

OBJECTIVE: This study highlights the relationship between some eating habits and iron status during pregnancy. SUBJECTS: The study included 219 healthy pregnant women aged 27.6 ± 5.7 years from southern Bulgaria. METHODS: Subjects' iron status was assessed on the basis of the following iron indicators: hemoglobin (Hb), serum ferritin (SF), serum transferrin receptor (sTfR), and body iron index (mg/kg). RESULTS: Severe anemia among the women from southern Bulgaria was not observed. Advanced pregnancy and some eating habits are factors that deteriorate iron status. Women who had consumed fish at least 3 times a week had lower levels of sTfR (р = 0.008), higher levels of SF (р = 0.05), and lower levels of body iron (р = 0.018). Frequent legume consumption was related to increased levels of sTfR (р = 0.036). Pregnant women with a high frequency of coffee consumption had lower values of body iron (р < 0.0001). Women who had consumed cow's milk at least 3 times a week had lower levels of SF (р = 0.026) and body iron (р = 0.042). CONCLUSIONS: Regular consumption of fish and legumes, rarely drinking coffee, and milk consumption during the intervals between food intake are conditions for optimization of iron status during pregnancy.

High-nitrate levels in drinking water may be a risk factor for thyroid dysfunction in children and pregnant women living in rural Bulgarian areas.

Nitrate inhibits the accumulation of iodide in thyroid gland. The aim of present study was to evaluate the influence of this ion on the iodine status of two risk population groups. Subjects of study were pregnant women and children aged between 3 and 6 years from two villages in Bulgaria with high- and low-nitrate levels in drinking water. The relative risk of thyroid disorders for the pregnant women living in the village with high-nitrate levels in drinking water expressed as an odds ratio was 5.294 (95% confidence intervals 1.003-27.939; P=0.0454) and was considered as significant. Statistically significant differences were found between the goiter rate in exposed and non-exposed pregnant women. The relative risk of thyroid dysfunction for the children exposed to a high-nitrate level, expressed as an odds ratio was 2.333 (95% confidence intervals 0.8491-6.412; P=0.1396) and was considered as not significant; the goiter prevalence in the exposed children was also not statistically different. The results of the study confirmed the role of high-nitrate level in drinking water as a risk factor for thyroid dysfunction in vulnerable population groups.

Iodine status and goitre prevalence in nitrate-exposed schoolchildren living in rural Bulgaria.

Nitrate and perchlorate are well-known water pollutants that are harmful to human health. They may inhibit the accumulation of iodide in the thyroid gland. The present study investigated iodine status and goitre prevalence in schoolchildren aged 7-14 years from two villages in Bulgaria with high and low levels of nitrate, and negligible levels of perchlorate in drinking water. Comparison between the mean and median urinary iodine concentrations of the exposed and non-exposed children showed a statistically significant difference for the boys. A statistically significant difference was also found for goitre prevalence between the exposed and non-exposed children. The relative risk for schoolchildren exposed to a high level of nitrate in drinking water, expressed as an odds ratio, was 3.014 (95% confidence intervals 1.293-7.027; P=0.0105) and this was considered to be significant. This study confirmed that a high level of nitrate in drinking water is a risk factor for thyroid dysfunction in this population.

New standardised texts for assessing reading performance in four European languages.

AIMS: To develop standardised texts for assessing reading speed during repeated measurements and across languages for normal subjects and low vision patients. METHODS: 10 texts were designed by linguistic experts in English, Finnish, French, and German. The texts were at the level of a sixth grade reading material (reading ages 10-12 years) and were matched for length (830 (plus or minus 2) characters) and syntactic complexity, according to the syntactic prediction locality theory of Gibson. 100 normally sighted native speaking volunteers aged 18-35 years (25 per language) read each text aloud in randomised order. The newly designed text battery was then applied to test the reading performance of 100 normally sighted native speaking volunteers aged 60-85 years (25 per language). RESULTS: Reading speed was not significantly different with at least seven texts in all four languages. The maximum reading speed difference between texts, in the same language was 6.8% (Finnish). Average reading speeds (SD) in characters per minute are, for the young observer group: English 1234 (147), Finnish 1263 (142), French 1214 (152), German 1126 (105). The group of older readers showed statistically significant lower average reading speeds: English 951 (97), Finnish 1014 (179), French 1131 (160), German 934 (117). CONCLUSION: The authors have developed a set of standardised, homogeneous, and comparable texts in four European languages (English, Finnish, French, German). These texts will be a valuable tool for measuring reading speed in international studies in the field of reading and low vision research.

Iodine status of children living in areas with high nitrate levels in water.

Several researchers have suggested a possible relationship between nitrate intake and the development of goiter in children. The present cross-sectional study included schoolchildren between the ages of 11 and 14 years from 2 villages in Bulgaria with high and low nitrate levels in drinking water. The comparison between the median urinary iodine levels of the total number of exposed (179.0 microg/l) and nonexposed (202.50 microg/l) children showed statistically significant differences. The relative risk for the children exposed to high nitrate levels in drinking water, expressed as the odds ratio, was 8.145 (95% confidence interval = 1.67-39.67). The authors considered this to be very significant. They found a statistically significant difference for the prevalence of goiter among the exposed and nonexposed children. The results of the study confirmed the role of high nitrate levels in drinking water as a health risk factor for thyroid dysfunction.