Jelena Kos

[OP.2B.03] GLOMERULAR HYPERFILTRATION AS A RISK FACTOR FOR RENAL IMPAIRMENT AND HYPERTENSION IN APPARENTLY HEALTHY SUBJECTS.

Objective: Chronic kidney disease(CKD) is established CV risk factor, and already early renal impairment(RI) increases risk for hypertension(HT) and loss of renal function. It was reported that blood pressure (BP) and metabolic derangements are associated with glomerular hyperfiltration(GHF), and GHF increases risk of developing microalbuminuria (MA) in HT stage 1. Our aim was to analyze whether GHF predicts progression to HT and RI in apparently healthy subjects. Design and method: Out of 954 subjects enrolled in ENAH follow-up study, 371 (137 m, 234 w; mean age = 46 years) were eligible for further analysis:100 with optimal, 72 with normal BP, 70 with PHT (high normal BP), and 129 with newly diagnosed untreated HT. Follow-up period was 77 ± 12 months. Exclusion criteria were treatment with antihypertensive drugs, diabetes, pregnancy, eGFR<60 ml/min, CV or cerebrovascular incident, chronic terminal diseases, dementia, immobility and missing data. BP and heart rate were measured using Omron 6 device following the ESH guidelines. Uric acid, glucose, lipids, serum creatinine, hsCRP, leptin and adiponektin were determined; HOMA index was used to calculate insulin resistance and MDRD formula to estimate GFR. Albumin to creatinine ratio (ACR) was determined from the first morning spot urine. GHF was defined as eGFR above the cut off value of the 5th quintile of the whole group. Results: In the GHF group eGFR(ml/min/year) decreased significantly more than in others (−3.4 (IQ−5.8 to −1.76 vs. −1.5 (IQ−2.6 to −0.3); total decrease −17.7% vs. −9.8%; per year −2.8% vs. −1.5%; all p < 0.001). ACR was non-significantly higher in GHF group at enter and at the end of follow-up (5.73 (IQ3.35–8.6) vs. 4.5 (IQ3.31–7.25); p = 0.06, 5.93 (IQ4.26–8.64) vs. 5.7 (IQ4.08–9.82; NS, respectively). In the GHF group, at the end of follow-up ACR did not increase significantly. At enter and at the end of follow-up BP was significantly lower in GHF group (p < 0.001). At the end of study we failed to observe difference in increase of BP and new-onset HT between GHF and others. Conclusions: In our group of healthy subjects GHF was associated only with more rapid decrease of GFR. No impact of GHF on ACR increase and development of new-onset HT in healthy subjects was observed. GHF has less prominent effect on HT and kidney function in apparently healthy subjects than in those with HT and metabolic disorder.

Chronic Dietary Exposure to Aristolochic Acid and Kidney Function in Native Farmers from a Croatian Endemic Area and Bosnian Immigrants

BACKGROUND AND OBJECTIVES Improvements in agricultural practices in Croatia have reduced exposure to consumption of aristolochic acid-contaminated flour and development of endemic (Balkan) nephropathy. Therefore, it was hypothesized that Bosnian immigrants who settled in an endemic area in Croatia 15-30 years ago would be at lower risk of developing endemic nephropathy because of reduced exposure to aristolochic acid. To test this hypothesis, past and present exposure to aristolochic acid, proximal tubule damage as a hallmark of endemic nephropathy, and prevalence of CKD in Bosnian immigrants were analyzed. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS In this cross-sectional observational study from 2005 to 2010, 2161 farmers were divided into groups: indigenous inhabitants from endemic nephropathy and nonendemic nephropathy villages and Bosnian immigrants; α-1 microglobulin-to-creatinine ratio >31.5 mg/g and eGFR<60 ml/min per 1.73 m(2) were considered to be abnormal. RESULTS CKD and proximal tubule damage prevalence was significantly lower in Bosnian immigrants than inhabitants of endemic nephropathy villages (6.9% versus 16.6%; P<0.001; 1.3% versus 7.3%; P=0.003, respectively); 20 years ago, Bosnian immigrants observed fewer Aristolochia clematitis in cultivated fields (41.9% versus 67.8%) and fewer seeds among wheat seeds (6.1% versus 35.6%) and ate more purchased than homemade bread compared with Croatian farmers from endemic nephropathy villages (38.5% versus 14.8%, P<0.001). Both Croatian farmers and Bosnian immigrants observe significantly fewer Aristolochia plants growing in their fields compared with 15-30 years ago. Prior aristolochic acid exposure was associated with proximal tubule damage (odds ratio, 1.64; 95% confidence interval, 1.04 to 2.58; P=0.02), whereas present exposure was not (odds ratio, 1.31; 95% confidence interval, 0.75 to 2.30; P=0.33). Furthermore, immigrant status was an independent negative predictor of proximal tubule damage (odds ratio, 0.40; 95% confidence interval, 0.19 to 0.86; P=0.02). CONCLUSIONS Bosnian immigrants and autochthonous Croats residing in endemic areas are exposed significantly less to ingestion of aristolochic acid than in the past. The prevalence of endemic nephropathy and its associated urothelial cancers is predicted to decrease over time.

Is herbal tea consumption a factor in endemic nephropathy

Endemic (Balkan) nephropathy (EN) is a chronic tubulointerstitial nephropathy frequently associated with upper urothelial cancer exclusively affecting farming villagers [1–3]. Based on our results, EN is considered to be an environmental form of aristolochic acid nephropathy (AAN) [1–3]. AAN was first reported in 1993 in Belgium and subsequently more AAN cases were reported worldwide as AA has been an integral part of traditional herbal medicines [4]. The extent of this problem was recently documented in Taiwan where precise data on prescriptions of herbal products containing AA is available [5]. Aristolochia spp. has been used for more than 2,000 years in the practice of traditional medicine and European physicians were familiar with the use of this plant as well. After its intrinsic toxicity became known, importing Aristolochia herbs was banned in many countries, including Croatia. Nevertheless, products containing AA remain a part of traditional medicine and are sold in many countries that do not have strict control protocols. Recently we reported that AA DNA adducts were present in 95 % of patients with EN who underwent surgery for upper urothelial cancers [2] and affirmed the idea that bread contaminated with AA might be the cause of EN [6, 7]. However, the causative relationship between AA and EN again raised the question whether bread intake is the only route of ingestion or whether AA was ingested also in EN as a part of folkloric medicine. Gluhovschi et al. [8] reported that although therapeutic remedies based on AA products are used in the EN affected area in Romania, no relationship between these remedies and the development of EN or of tumors was observed. However, they used HPLC for detection of AA in plasma, which is less sensitive than the mass spectrometry we recently used in tissue samples [1, 2]. In addition, when re-analyzing their data, it does appear that AA was used more frequently in the endemic area. In our opinion, this leaves the question whether herbal tea may play a role in EN still unanswered. In our preliminary study we failed to find any evidence in the group of 1,041 Croatian farmers that herbal tea or traditional medicine use is related to EN [9]. The observed differences between

Reliability of CKD-EPI predictive equation in estimating chronic kidney disease prevalence in the Croatian endemic nephropathy area.

Introduction Chronic kidney disease (CKD) is a significant public health problem and it is not possible to precisely predict its progression to terminal renal failure. According to current guidelines, CKD stages are classified based on the estimated glomerular filtration rate (eGFR) and albuminuria. Aims of this study were to determine the reliability of predictive equation in estimation of CKD prevalence in Croatian areas with endemic nephropathy (EN), compare the results with non-endemic areas, and to determine if the prevalence of CKD stages 3-5 was increased in subjects with EN. Materials and methods A total of 1573 inhabitants of the Croatian Posavina rural area from 6 endemic and 3 non-endemic villages were enrolled. Participants were classified according to the modified criteria of the World Health Organization for EN. Estimated GFR was calculated using Chronic Kidney Disease Epidemiology Collaboration equation (CKD-EPI). Results The results showed a very high CKD prevalence in the Croatian rural area (19%). CKD prevalence was significantly higher in EN then in non EN villages with the lowest eGFR value in diseased subgroup. Conclusions eGFR correlated significantly with the diagnosis of EN. Kidney function assessment using CKD-EPI predictive equation proved to be a good marker in differentiating the study subgroups, remained as one of the diagnostic criteria for EN.

Adiponectin is Not Associated With Blood Pressure in Normotensives and Untreated Hypertensives With Normal Kidney Function

AbstractThe role of adiponectin in hypertension is still a matter of debate. Obtained conflicting results could be mostly explained with diversity of subjects included in different studies. Our aim was to analyze association of adiponectin with blood pressure (BP) in a group of normotensive and untreated hypertensive subjects.Participants (N = 257) were selected from a random sample of 2487 subjects enrolled in an observational cross-sectional study. Subjects with diabetes and chronic kidney diseases were excluded. BP was measured using Omron M6 device following ESH/ESC guidelines. Adiponectin concentration was determined by ELISA.There were no differences in adiponectin values (mg/L) between hypertensives and normotensives (median 9.75; iqr: 7.44–17.88 vs 11.35; iqr: 7.43–12.63; P = 0.17). On univariate linear regression adiponectin was not associated with systolic or diastolic BP (P > 0.05). Furthermore, multivariate analysis did not show significant contribution of log-transformed adiponectin either to systolic (&bgr; = −0.040; P = 0.43) or diastolic BP (&bgr; = 0.066; P = 0.33).In our group of normotensives and untreated hypertensives with normal kidney function adiponectin was not associated with BP even after adjustment for other risk factors. Our results and conclusions should not be extrapolated to subjects with other characteristics.

NEGATIVE TREND IN ASSOCIATION OF UROMODULIN WITH BLOOD PRESSURE IN PREHYPERTENSIVES AND UNTREATED HYPERTENSIVES WITH NORMAL KIDNEY FUNCTION

Objective: Uromodulin and minor G allele UMOD gene rs13333226 have been associated with blood pressure (BP), hypertension (HT) and better renal function. Our aim was to analyze the association of uromodulin and the frequency of G allele with BP and kidney function in untreated subjects with a normal glomerular filtration rate (GFR). Design and method: From 894 participants of the ENAH follow up, a cohort group of 559 untreated subjects (men 55.8 %, cohort group mean age 38.6) with an eGFR > 60 ml/min/1.73m2 (CKD Epi equation) were enrolled into the study. Subjects were divided in three subgroups: optimal BP (OBP; N = 107), prehypertension (PHT; N = 145) and HT (N = 307). UMOD genotyping rs12917707polymorphism was performed by RT-PCR with the fluorescence-based TaqMan system, while urinary uromodulin levels were measured by Enzyme Linked Immunosorbent Assay (ELISA). Results: We failed to find difference in uromodulin levels among BP categories. However, a negative association of uromodulin with systolic BP (NS) and diastolic BP (r = 0.20; p = 0,069) was observed in the entire group. No association between uromodulin and eGFR was noted. Uromodulin was found to be lower in women than men. The frequency of A and G alleles was 83.2% and 16.8%, respectively. No difference in the frequency of G allele was found among the BP categories. A trend of higher uromodulin was observed in homozygous for the G allele. No significant trend was observed between uromodulin and eGFR in the entire group. Conclusions: There is trend of negative association of uromodulin with BP in middle-aged untreated subjects with normal kidney function. We did not find an association of uromodulin with eGFR. A trend of a higher uromodulin urine concentration was observed in subjects with the G allele of UMOD rs13333226.

POSITIVE TRENDS IN AWARENESS OF HARMFUL EFFETCS OF HIGH SALT INTAKE - 10 YEARS CROATIAN ACTION ON SALT AND HEALTH (CRASH). DATA FROM 2008 AND 2017 WORLD HYPERTENSION DAYS

Objective: The aim of this study was to evaluate changes in general population attitude and awareness on harmful effects of high salt consumption ten years after Croatian national action on salt and health (CRASH) was launched. Design and method: Data on salt awareness were collected in individuals (aged 18 years or older) participating in the 2008 and 2017 World Hypertension Day in Croatia. In 2017 blood pressure (BP) was measured at 26 sites in 5 cities in Croatia from 10 AM to 2 PM in hospital open points, central squares and pharmacies. BP was measured by physicians, trained nurses, pharmacist or medical students. Along with BP measurements, a short questionnaire on hypertension awareness, salt intake and smartphone use was completed at the time of the interview. This action was organized and supported by the Croatian Society of Hypertension. Results: A total of 2175 subjects, 873 (40.1%) men, 1211 (59.9%) women were examined. Awareness that increased salt intake is harmful and associated with high BP significantly increased from 2008 to 2017 (65.3% vs.95.8%);in 2017 women are more aware (91.8% vs.87.3%;p = 0.013). Comparing to 2008, in 2017, population is much more informed about harmful effects of exaggerated salt intake from physicians (48.9% vs.89.1%). In 2017 more subjects are aware that they are eating too salty than they were in 2008 (27% vs.36.1%), and more men than women thinks they are eating too salty (36.1% vs.29.8%,p = 0.02). Comparing data from 2008 and 2017 the same proportion of women believes that they would be able to reduce salt intake if suggested (86.5% vs.85.8%), but significantly more men in 2017 compared to 2008 declared that they could follow recommendations for reducing salt intake (62% vs.83.9%). Although significantly more subjects in 2017 than in 2008 are aware that bread and bakery products are the main sources of salt intake (9.5% vs.20.9%), the majority (52%) still believes that smoked meat, salami etc. is the main pathway of salt ingestion. Conclusions: Significant improvements in awareness of harmful effects of high salt consumption were noticed in Croatia.

FIXED DOSE COMBINATION THERAPY IS ASSOCIATED WITH BETTER BLOOD PRESSURE CONTROL AND LOWER ALBUMINURIA IN REAL-LIFE COHORT DURING 7 YEARS OF FOLLOW UP. ENAH – CROATIAN RURAL STUDY

Objective: The aim of this study was to analyze differences in blood pressure (BP) control and albuminuria between subjects treated with fixed dose combination (FCD) and those treated with free components in real-life during the 7 years follow up period. Design and method: Out of 1134 subjects (door-to-door enrollment, participation rate 80%) data on 236 (54 men; 182 women; mena age 63.2 years) treated hypertensives (HT) were analyzed at the end of 7 years of follow-up. At enter 136 of them were already treated HT (group A) and 100 were new-diagnosed HT (group B) who had started with antihypertensive therapy from that moment. Local GP were allowed to tailor antihypertensive therapy during the follow up period. At basal and at the end of follow up BP was measured by physicians who were project collaborators (ESH/ESC guidelines; OmronM6); salt intake (spot urine - Kawasaki equation), eGFR (CKD-Epi) and albumin-to-creatinin ration (ACR mg/g;first morning urine sample) were analyzed in central lab. Pregnant women, terminal ill, bed-ridden patients, those with severe disability, mentally ill or suffering from dementia or at least one limb amputated/immobilized were exclided. Results: At the end of follow up BP controll was achieved in 31.6% and 38% of HT (group A and B, respectively). In both groups, there there were no significnat differences in salt intake, BMI, smoking and the number of used drugs between controlled and uncontrolled subjects (p < 0.05). However, in group A significant increase in FDC prescription was observed ih the controlled vs.uncontrolled subjects (22% vs. 5.5%). BP control was associated with lower ACR in group A (14.9 vs.76.3; p < 0.01) and group B (9.1 vs.24.9; p < 0.05). Conclusions: In this real-life cohort after 7 years of follow-up BP controll was ahived with more drugs but only if used as FDC what was associated with better organoprotection i.e.lower ACR. Overall poor BP control and organoprotection could be improved using more FDC.

[PP.30.29] PREHYPERTENSION AND SINGLE NUCLEOTIDE POLYMORPHISM RS13333226 OF THE UROMODULIN (UMOD) GENE

Objective: Single nucleotide polymorphism of UMOD gene rs13333226 and its G minor allele were found to be associated with lower blood pressure (BP) values. The aim in this study was to analyze the relationship of this polymorphism with prehypertension (PHT) in general population and here we are reporting preliminary cross-sectional results. Design and method: Out of 3056 subjects enrolled in ENAH study, 496 were eligible for further analysis. Exclusion criteria were treatment with antihypertensive drugs, diabetes, pregnancy, eGFR<60 ml/min, cardiovascular or cerebrovascular incident, chronic terminal diseases, dementia, immobility and missing data. BP and heart rate were measured using Omron 6 device following the ESH guidelines. PHT was defined following the JNC 7 guidelines as a BP >=120/80 and <140/90 mmHg, and normotension (NT) as a BP <120/80 mmHg. Clinical and laboratory data were obtained by routine methods and polymorphism was obtained with TaqMan® real time PCR method. Results: Prevalence of genotypes and G minor allele in overall population were A/A 68.5% (N = 340), A/G 29.6% (N = 147), G/G 1,8% (N = 9) and G minor allele 16% (N = 165). Distribution of all genotypes and G minor allele did not differ significantly between groups of participants with PHT and NT. Logistic regression showed that none of the observed genotypes were predictors for PHT. Common risk factors such as gender, age and body mass index affect systolic BP and the estimated glomerular filtration in all genotypes equally. Conclusions: We failed to find neither an association of uromodulin gene (SNP rs13333226) with BP in normotensive subjects nor this SNP was predictor of prehypertension. In this ongoing study we will enlarge the sample what might enable us to detect small changes in BP phenotype, and in follow up period will analyze predictive value of this polymorphisms for development of sustained hypertension.

[PP.30.14] SALT CONSUMPTION IN CROATIAN CONTINENTAL RURAL POPULATION: ENAH STUDY

Objective: Results from our previous survey confirmed that salt consumption (24 h mapping) in Croatia is above 11 g/day. Salt intake was higher in rural than in urban area. Croatian national campaign started in 2008 and our aim was to analyze trends in salt consumption in rural area in the past period. Design and method: Out of 3056 subjects enrolled in ENAH study, 2259 (868m, 1391w) were eligible for further analysis. All inhabitants older than 18 years of age from this rural area were invited to participate and were examined on a door-to-door basis. Pregnant women, patients with terminal illness who were bed-ridden, patients with severe disability or those who have had at least one limb amputated or immobilized and mentally ill or suffering from dementia were considered ineligible. Participation rate was >70%. Salt intake (g/day) was estimated from the first morning spot urine using Intersalt equation. Blood pressure (BP) was measured using Omron 6 device following the ESH guidelines. Villagers were examined in 2008, 2010 and 2015 and trends in salt intake and association with BP were analyzed. There were no differences in age and gender between survey years. Results: In 2008, 2010, 2015 salt intake in the whole group was 10.5(8.7–12.2); 10.2(8.4–12.1); 10.9 (9.5–12.2), respectively; in men 10.4(8.8–12.2); 10.1(8.5–12.1);10.9 (9.3–12.3), respectively; in women 10.6 (8.6–12.3); 10.4(8.4–12.1); 10.9 (9.6–12.1), respectively. We failed to observe trend in decreasing salt intake, without gender difference. Significant correlation between salt intake and systolic and diastolic BP was found in the whole group (r = 0.32; r = 0.18, respectively, both p < 0.001), in men(r = 0.29; r = 0.134, respectively, both p = 0.01) and in women (r = 0.35; r = 0.21, respectively, both p < 0.001). Conclusions: We are fully aware of many drawbacks related to the spot urine sampling. However, using the same method and the same equation in the same population we believe that we can consider our results reliable to estimate the trend of salt consumption in rural area. Significant correlation with BP was observed which confirms prior results. Despite of the Croatian National Program launched 10 years ago, salt consumption in rural area is very high and remains unchanged and further efforts in this field are needed.