Abstracts from the XIIth Scientific Meeting of the Argentine Society of Arterial Hypertension

Epidemiologic Survillance of Cardiovascular Disease Mollar G, Cavalieri L, Galarza C, Waisman G, Beratarrechea A, Petrlik E, Langlois E, Soriano F, Marchetti M, and Gonzalez B de Quirós F Programas Médicos de Plan de Salud del Hospital Italiano de Buenos Aires

To enhance efficacy of health care, surveillance activities are required, especially with chronic prevalent diseases. Epidemiologic surveillance allows US to quantify and qualify health problems, settle priorities, identify high risk groups, manage and monitor health care systems, detect frequency changes in events, and assess performance of prevention and disease management programs. We have developed a surveillance system that identifies and reports daily on patients having cardiovascular disease (CVD) who are uncontrolled.

Objective: To evaluate the accomplishment of blood pressure (BP) measurement in people with CVD belonging to a health care system included in an epidemiological surveillance list.

Design: Cohort study between 1/1/2004 and 9/1/2004.

Methods: Patients 60 years old or older identified by surveillance system during the first term of 2004, were followed up. Patients were identified as having CVD through electronic medical record using international classification for primary attention (ICPA).

Patients are reported by the software system when presenting any of the following criteria: no blood pressure record during the past 6 months, blood pressure above 140/90 in the last record, and if diabetic A1C above 7.5%.

The connection with the appointment system allowed us to detect previously the patient’s attendance and, 15 min before his or her medical appointment, send the patient to be examined by the executors of a chronic disease program, according to the JNC VII guidelines.

The BP measurement is a common intervention to most chronic diseases because it increases cardiovascular risk, hence it is considered a process indicator of the surveillance system.

Results: Of the 24,411 patients having CVD, 5506 (26%) were listed during the first term, mean age was 74 years and 65% were female. By the end of 2004, 4660 (85%) patients had blood pressure recorded with an average values of 136.76 mmHg for systolic and 77.51 for diastolic blood pressure. Blood pressure was assessed three times in average.

Conclusion: Surveillance system allowed identifying of and intervening in a high proportion of patients.

Blood Hypertension, Overweight, And Obesity in Schoolchildren From Corrientes City Poletti OH, Pizzorno JA, Alvarez VS, Enacán RE, and Barrios L. Department of Obstetrics and Gynecology and Department of Critical Care Medicine, Llano Hospital, Corrientes

Previously We have investigated obesity, overweight, and blood pressure (BP) to establish arterial hypertension prevalence, together with obesity, diabetes mellitus, and hypercholesterolemia (LDL cholesterol), are strong predictors of arteriosclerosis and morbimortality for cardiovascular accidents in adulthood.

Objective: To detect hypertension, overweight and obesity in schoolchildren.

Materials and Methods: The population sample consisted of 10- to 15-year-old children and adolescents of both sexes attending 6^th, 7^th, 8^th, and 9^th forms in 10 schools from Corrientes City center, subjects were randomly selected.

Blood pressure was measured from the subjects’ right arms while seated, and after 15 min of rest. A mercury manometer was used, and measures were expressed in mmHg. In those cases in which high values of BP were found, three measures with 5-min intervals were taken, and the mean was obtained.

The body mass index (BMI) was calculated according to the formula: BMI = weigth / height². The standards of task force on high blood pressure in children were used; the 95 percentile of blood pressure according to height, sex and age was taken as threshold.

Statistical Methodology: The mean, standard deviation, and linear correlation were calculated for continuous numerical variables. Percentages, and Chi2 test were used to compare proportions.

Results: So far samples from 999 schoolchildren of both sexes attending four state and private schools have been studied: 536 females (54%) and 461 males (46%). Mean age: 12.1 ± 1.5 years. Nutritional status: 78.5% of the population had normal BMI, 16.6% presented overweight, and 4.9 % obesity. Blood pressure: mean SBP-113.3 ± 11.6mmHg, DBP-73.9 ± 9.0 mmHg, MBP-87.0 ± 9.3 mmHg. Arterial hypertension was detected in 18.9% (20.1% female and 17.5% male) (p: 0.16).

The regression analysis test revealed positive correlation between BMI and MBP (R: 0.32, r²: 0.1, p: 0.0001), BMI and DBP (R: 0.26, r²: 0.07, p:0.001), and BMI and SBP (R: 0.37, r²: 0.14, p: 0.0001).

Discussion: The results revealed the presence of high hypertension prevalence in the schoolchildren under study. Positive correlation among MBP, DBP, and SBP with BMI was found, indicating a higher degree of hypertension in the obese and overweight groups than in the normal BMI group.

The high degree of hypertension detected is important. The relationship between hypertension, overweight, and obesity shows the necessity to carry out programs to detect, control, and follow-up high blood pressure in schoolchildren. It is also necessary to design proper strategies to promote programs of nutritional education at schools, aimed at producing changes in healthy eating habits and physical activity.

Effect of Different Na⁺/h⁺ Exchanger Inhibitors On Lv Mass And Lv Systolic Function: Echocardiographic analysis in spontaneously hypertensive rats Tufare AL, Escudero EM, Ennis IL, Garciarena CD, Carranza VB, and Pinilla OA. Centro de Investigaciones Cardiovasculares. Fac. de Ciencias Médicas, UNLP

The inhibition of Na⁺/H⁺ exchanger (NHE-1) reduces the hypertrophy on the hearts of spontaneously hypertensive rats (SHR). Even though the reduction of left ventricular hypertrophy (LVH) is one of the principal goals in the clinical management of hypertension, LVH is thought to develop as an adaptive response by which LV wall stress is moderated and LV systolic function is supported. However, the majority of basic studies, and also several clinical observations, indicated a depressed inotropic state in LVH. The aim of this study was to analyze by echocardiogram, the action of two NHE-1 inhibitors (HOE 642 and BIIB 723) on LV mass and LV systolic function. We studied 16 SHR, 8 treated with HOE 642 30 mg/kg/day, 8 with 30 mg/kg/day of BIIB 723 during 30 days and 4 SHR as controls during 30 days. Results are expressed as mean values ± SEM. The parameters examined did not evidence changes during that period in the controls rats.

Even though the HOE 642 determined a slight decrease in blood pressure (C: 184 ± 1.7 mmHg; HOE 642 30d:176.2 ± 2.6 mmHg – p < 0.01) not detected with BIIB 723, both drugs provoked an increase of peak systolic stress (C:166 ± 29 kdynas/cm²; HOE 642 30d: 204 ± 34 kdynas/cm² – p < 0.04; C: 164 ± 26 kdynas/cm2; BIIB 723 30d: 234 ± 29.3 kdynas/cm2 – p < 0.02). Treatment with HOE 642 and BIIB723 reduced significantly LV mass (C: 612 ± 50 mg; HOE 642 30d:452 ± 37 mg – p < 0.01. C: 544 ± 16 mg; BIIB 723 30:d 374 ± 25 mg – p < 0.01) in similar proportion (HOE 642: 26%.BIIB 723: 31% – n.s). Endocardial fractional shortening did not change after HOE 642 (C: 62.3 ± 2.75% – HOE 642 30d:65.5 ± 2.4% – ns) or BIIB723 (C:62.2 ± 2.39% – BIIB723 30d: 67.2 ± 1.62% – ns) administration. Midwall ventricular shortening increased after 30 days of treatment with HOE 642 and BIIB (C:25.5 ± 1.7%; HOE 642 30d: 27.9 ± 2.4% – p < 0.01. C: 22.2 ± 0.63% – BIIB723 30d: 30 ± 1.78% – p < 0.04)

These evidences allow us to conclude that both inhibitors determined similar reduction of LVM with improvement in the LV systolic function, probably for the increase of inotropism, previously compromised during the development of the hypertrophy.

Stationary and Dynamic Hemoreologic Studies on Hypertensive Patients Filippini F,³ Foresto P,^{1, 2} Riquelme B,^{1, 2} D’Arrigo M,^{1, 2} Racca L,⁴ Barberena L,³ Gallo R,³ Valverde J^{1, 2 1}Laboratorio de Inmunohematología y Area Física. Fac. de Cs. Bioquímicas y Farmacéuticas. ²Grupo de Optica Aplicada a la Biología, IFIR (CONICET-UNR) ³Clínica Médica. Facultad de Cs. Médicas. UNR. Rosario ⁴Area Estadística.

Several research teams have developed studies about hemoreologic abnormalities, focusing on the vascular tree analysis or their blood component as a fluid. The reologic properties at the cellular level remain a mystery, so far. The red blood cell shows particular reologic properties due to its composition and membrane structure. The cellular membrane has three levels: 1. cytoskeleton; 2. lipid layer, 3 and glucocalix. Even though each one has particularities, a change in any of leads, to the membrane’s reologic alteration. Membrane’s characteristic viscoelastic behavior is produced by cooperation of the cytoskeleton (elastic component) and the lipid layer (viscosity component), displaying an interaction between the cellular membrane levels. The parameters that qualify the cell membrane while on its stationary stage are deformability index (ID), elastic module (μ), superficial viscosity of membrane (η_m) and time of characteristic delay (tc).

The cellular reaction to the oscillation frequency is known as complex or dynamic viscosity. This reaction is produced in a transitory and pulsating regimen, modeling physiological blood circulation in a periodic regimen similar to the one that is produced with a cardiac pulse. The pulsation frequency has its own parameters: dynamic elasticity, G’; dynamic lost, G’’; viscous component of dynamic viscosity, η. Both stationary and dynamic parameters may be determined by laser difractometry. Summing up, the erythrocyte membrane is a complex structure, with high levels of specialization, and both factors can be proved by analyzing the reologic behavior. The slightest injury in any of the components will produce higher levels of fragility and will affect characteristic parameters, modifying both cell deformability and blood fluid circulation.

The aim of this investigation is the analysis of the erythrocyte membrane’s dynamic and stationary parameters in hypertensive patients, compared with normotensive subjects. For this purpose, the investigation required EDTA anticoagulated blood from 13 hypertensive patients (HTA) and 20 healthy individuals (HI). Hemoreologic parameters where determined by laser difractometry in stationary and in dynamic conditions similar to a 60 cycles per min cardiac rhythm. These parameters allow the investigation of erythrocyte behavior during circulation, evaluating reaction and recovery capacity in different fluid conditions. The results are expressed as ξ ± SD. The Mann Whitney test was employed to compare two independent samples.

Results: DI: 0.69 ± 0.03 (HTA), 0.64 ± 0.04 (HI) NS; μ (10⁻⁶ N/m): 8.1 ± 1.2 (HTA), 5.3 ± 1.8 (HI) p < 0.05; η_m (10⁻⁷ N.s/m): 3.6 ± 0.3 (HTA), 3.8 ± 1.0 (HI) NS; t_c (10⁻¹s): 0.44 ± 0.10 (HTA), 0.77 ± 0.18 (HI) p < 0.05; G’: 7.3 ± 0.9 (HTA), 4.75 ± 1.5 (HI) p < 0.05; G”: 3.52 ± 0.40 (HTA), 2.0 ± 0.6 (HI) p < 0.05; η’: 0.56 ± 0.06 (HTA), 0.31 ± 0.09 (HI) p < 0.05.

Results show an alteration of reological parameters of erythrocyte membrane in hypertensive patients compared with healthy subjects.

Conclusion: This study offers important information related to membrane properties in tension conditions similar to those produced during circulation. Recent investigation in this field has confirmed the importance of different blood aspects, such as intercellular interaction (adhesion, aggregation, and aglutination); circulating cell interaction with vascular walls (circulatory and microcirculatory reopaties), hematic and membrane pathology, and gas and metabolic transportation. Diagnose in clinical medicine can be supported and amplified by hemoreological analysis.

Early Clinical Identification of Patient With Risk of Preeclampsia-eclampsia Rivero M, Feu C, Perna E, and Pizzorno J Department of Obstetrics and Gynecology and Department of Critical Care Medicine, Llano Hospital, Corrientes

SUMMARY

Objective: To evaluate prevalence and risk factors of preeclampsia/eclampsia (PE) and to analyze the prognostic usefulness of clinical variables to identify pregnant women at risk.

Methods: Retrospective analysis of database from 11,026 consecutive childbirths, attended from November 1998 to June 2004. Preeclampsia was diagnosed in the presence of both blood pressure ≥140–90 (2 occasions) and proteinuria, eclampsia was defined by the appearance of convulsions. A prediction score was elaborated using the odds ratio of the variables significantly associated with PE in the multiple logistic regression analysis. The area under ROC curve was used to determine the cut-off and utility of the score.

Results: PE was identified in 329 (3%) patients. The variables significantly associated with PE were: first pregnancy (OR = 3.1, p < 0.0001), maternal age ≥35 years (OR = 1.7, p = 0.002), previous arterial hypertension (OR = 3.3, p < 0.0001), multiple pregnancy (OR = 4, p < 0.0001), obesity, (OR = 2.6, p < 0.0001), and time interval between deliveries ≥3 years (OR = 1.6, p = 0.003). The prediction score showed an area under the ROC curve for diagnosis of PE of 0.68. A cut-off of 2.1 showed a sensitivity and specificity of 68 and 60%, whereas for 3.7 they were 29 and 92%, respectively. For each unit of increment of the score, the risk of PE was of 2.5 (IC 95% = 2.2 – 2.9, p < 0.0001).

According to the score, the population was classified in low risk (≤2.1, 59%), intermediate risk (2.2–3.6, 32%), and high risk (≥3.7, 9%), with an incidence of PE of 1.6, 3.5 and 9.4% (p < 0.0001)

Conclusion: The PE was found in 3% childbirths. The risk factors were found in the medical history (age, hypertension, weight, height, parity) and current pregnancy (multiple pregnancy). The use of a score based on these approaches allows us to identify pregnant women at risk of PE.

Biomechanical Differences in Large, Medium, and Small Systemic and Pulmonary Arteries Bia D, Zocalo Y, Cabrera-Fischer EI, Pessana F, and Armentano R Favaloro University, Buenos Aires

Background: Atheroesclerotic diseases show different incidences in the arterial tree. These differences could be due to viscoelastic properties of the arterial wall. Pulse pressure (P), determined by the beating activity of cardiac function, is not always dampened by the arterial wall. This buffer function is determined by the elasticity-viscosity relationship of the arterial wall.

Purpose: To characterize elastic (E), viscous (V), and arterial wall protective capacity (PC) of systemic and pulmonary arteries.

Methods: Systemic (A1: ascending aorta; A2, A3, A4: upper thoracic, lower descending and abdominal aorta; CC: common carotid artery) and pulmonary artery segments (P1: pulmonary trunk; P2: left pulmonary trunk branch), were obtained from 9 Corriedale sheep. All were in vitro studied through a circulating loop that mimics the physiological state. P and diameter (D) values were obtained using pressure micromanometer (Konigsberg) and a pair of ultrasonic crystals, respectively. The elastic (E, mmHg/mm) and the viscous (V, mmHg s/mm) indexes were calculated from the P-D relationship using a Kelvin-Voigt model, obtaining by iteration the minimal hysteresis area value that preserves the clockwise direction. Pulse Pressure was calculated by the following formula: PC = V/E², 10⁻⁴ mm·s/mmHg.

Results:

Table

Conclusion: Both nin systemic and pulmonary arteries, E and V increase and PC decreases from heart to periphery. Curiously PC shows lowest values in systemic circulation where atherosclerotic disease is frequently observed. Besides, the highest values of PC in systemic arteries were observed in medium and small vessels, where the diagnosis of atherosclerosis diseases is frequently performed. Consequently, atherosclerotic disease could be due, at least partially, to viscoelastic arterial wall properties differences.

Arterial Hypertension, Multifactorial Herence, and Primary Prevention Soldano OR, Bassan ND, Vinuesa MA, Bruera GM, and Sciarresi EA Rosario School of Medicine, Universidad Abierta Interamericana, Rosario.

Almost 95% of the hypertensive patients undergo an essential arterial hypertension whose polygenic herence is still studied. When this genetic background interacts with environmental factors related with food intake, physical activity, stress, and drug consumption, subjects genetically predisposed may develop the aforesaid disease.

In this context, this experience was based on the detection of the referred genetic background in private medical school students as well as in their relatives. It was subsequently complemented by an appropriate training of the students for primary prevention.

A total of 157 students studying human genetics analyzed their own arterial pressure pedigree comprising also their first- and second-degree relatives. Fully 31 students (20%) showed no familiar antecedents of arterial hypertension whereas 68 students (43%) revealed antecedents of this disease in their first-degree relatives. This percentage reached 80% when both degrees were considered.

Taking into account these results, an instructive module was designed for supporting promotive and preventive actions on their relatives.

To sum up, knowing the arterial pressure pedigree and applying the proposed instructive module, general physicians and specialists may contribute to diminishing the risk of appearance of arterial hypertension in predisposed subjects by acting on the cited environmental factors.

Arterial Blood Pressure and Intrinsic Heart Rate: Involvement of Cardiac Nitric Oxide Pathway and Thyroid Gland. Fellet A,¹ Arza P,¹ Arreche N,¹ Bustamante J,² Arranz C,¹ Boveris A,² and Balaszczuk AM^1.1 Cátedra de Fisiología, ²Laboratorio de Radicales Libres, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Iquimefa-Conicet

Acute administration of N^G-nitro-L-arginine methyl ester (L-NAME, 7.5 mg/kg) increased mean arterial pressure and heart rate (18%) in autonomic blocked anesthetized rats. This positive chronotropic effect was partially blocked by thyroidectomy, whereas the effect on blood pressure was not affected. After 150 min of autonomic blockade there was a 61% decrease, from 54 to 21 nmol NO/ming heart, in the total Nitric oxide (NO) production by heart nitric oxide synthases (NOS). The activities of mtNOS and sarcoplasmic reticulum eNOS were 74% and 52% decreased, respectively. Mitochondria isolated from whole heart, well coupled and able to carry out oxidative phosphorylation with high respiratory control and ADP:O ratios, showed decreased mtNOS functional activity (55–60 %) and protein expression (62 %), along with the decreased mtNOS biochemical activity from 0.53 to 0.14 nmol NO/min.mg protein. Right atrium histochemical NOS (NADPH-diaphorase) was 55 % decreased after heart denervation.

The referred changes were partially or almost totally prevented by thyroidectomy performed simultaneously to autonomic blockade. Western blot analysis indicates a mtNOS rapid turnover (t1/2 = 120 min) with a protein expression downregulated by thyroidectomy and with a degradation process downregulated by autonomic nervous system.

The observations suggest that NO-mediated pathways and thyroid gland contribute to the intrinsic pacemaker heart activity. This effect is likely through regulation of NO steady state levels in the right atrium and in the whole heart.

Effect of omapatrilat on Behavior ond Cerebral Structure of the Normal Aged Rat Basso N, Paglia N, Pietrelli A, Inserra F, and Terragno N Laboratorio de Fisiopatología Cardiovascular, Departamento de Patología, 2a Cátedra de Farmacología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires.

Former experiments have shown that chronic inhibition of angiotensin II (AngII) impairs the cognitive decline due to aging in the normal rat. This study has analyzed the effect of omapatrilat (OMA), a pharmacological agent that combines inhibition of the angiotensin-converting enzyme, and of the neutral endopeptidase involved in the metabolism of the atrial natriuretic peptide, on the reference (RM) and working memory (WM), the motor activity (MA), and the emotionality (E) in the aged normal rat. The histological structure of the CA1 area of the hippocampus also was determined.

Methods: Wistar male rats at weaning (n = 30) were divided in two groups: C (n = 14) received 0.1 % Na H CO3 solution to drink; OMA (n = 16) 30 mg/kg/day during 6 months and 20 mg/kg/day in the mentioned solution, thereafter, to drink. At 18 months of age they were trained in an eight-arm maze made of clear acrylic. Training was performed daily during 40 days by the same operator. The criterion for the acquisition of spatial memory was one single error in 5 consecutive days. In other groups of 18-months-old rats C or OMA the histological analysis, number of neurons, astrocites, and capillaries was performed. Tissues were stained with H&E and immunostaining was achieved with an avidin-biotin peroxidase modified technique, using the following antibodies: Von Willebrand FVIII factor for capillaries and protein S100 for astrocites.

Results: (x ± SEM) indicate that treated animals made less mistakes in WM (C: 2.86 ± 0.16 vs OMA: 2.32 ± 0.15*); need less time (C: 193.9 ± 7.3 vs OMA: 161.0 ± 6,6* seconds) to complete their task; and showed less emotionality (C: 1.00 ± 0.06 vs OMA: 0.40 ± 0.01 defecation pellets). Histological results showed the neuroprotective effect in the CA1 area of the hippocampus with a larger number of neurons per 500 μ: C: 49 ± 3 vs OMA: 95 ± 6* and of astrocites per field: C: 8.1 ± 0.7 vs OMA: 12.7 ± 0.8* (*p < 0,05).

Conclusion: The protective effect of this new agent on behavior alterations due to aging in the normal rat has been confirmed, and the evidences indicate that it is related to preservation of the neural structure that regulates its function.

Angiotensin II and Life Expectancy in the Normal Rat Cini R, Paglia N, Terragno N, and Basso N Laboratorio de Fisiopatología Cardiovascular, Departamento de Patología, 2a Cátedra de Farmacología, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires

Previous results have demonstrated that chronic inhibition of angiotensin II (AngII) with either enalapril (E) or losartan (L) reduced the cardiovascular, renal, cerebral, and hepatic damage due to aging in the normal rat. In this study the survival of these animals was analyzed.

Methods: Wistar male rats (n = 88) were used. One set (G1; n = 56) was separated at weaning and divided in three groups: Control (C) (n = 24) drank water; E1 (n = 16) received 10 mg/kg/day, and L1 (n = 16) received 30 mg/kg/day in the drinking water, beginning at 30 days of life. The remaining 32 (G2) were treated in the same way (E2; L2) but beginning at 12 months of life. At 2 years (730 days) the survival rate was: C: 58%; E1: 88%; L1: 94%; E2: 63%; L2: 69%.

Results: All the animals of group C died spontaneously before 27 months of age. In G1 treated animals, 11 rats of each group were alive at this age and died between 28 and 37 months. In G2, 6 rats of each group were alive at 27 months and died between 27 and 31 months. The young animal phenotype was better conserved in E animals, intermediate in L, and much deteriorated in C. Subcutaneous tumors were detected in 13 of the 24 C rats, in 1 of the 16 L1, in 6 of the 16 L2, and in none of the E treated. Results of survival days expressed as x ± S.E.M. were C: 735.1 ± 13.1; E1: 891.6 ± 36.8*; L1: 877.4 ± 34.0*; E2: 777.6 ± 29.7#; L2: 769.8 ± 26.3#; (*p < 0,0002 vs C; # p < 0,006 vs E1 o L1). The statistical analysis of the survival curves showed that the differences between the groups were significant (p < 0,0001) The study was performed using the Kaplan Meier test and applying the post hoc Scheffé test. The results confirm previous observations on the organs functional and morphologic damage.

Conclusion: Chronic inhibition of AngII increases life expectancy in the normal rat; the protective effect is larger when the treatment is begun at weaning and is probably mediated through the AT1 receptors of the polypeptide.

Effect of Education on Blood Pressure Control in the Elderly: A Randomized Controlled Trial Díaz Seone D, Galarza C, Figar S, Petrlik E, Hornstein L, Rodriguez L, Waisman G, Rada M, Soriano ER, and Gonzalez B. de Quirós F Hospital Italiano de Buenos Aires

It is not clear which educational strategy is most effective to help patients change their lifestyles. We compared the efficacy of two different educational models on reducing blood pressure (BP).

Methods: Randomized controlled trial in ambulatory hypertensive patients, older than 65 years. Four workshops aimed at developing self-management and patient empowerment (PEM) was compared with the same number of workshops based on compliance-based model (CM). Differences in reductions in systolic blood pressure at 3 months compared with basal records between groups (net reduction) measured by 24-h ambulatory monitoring.

Results: 30 patients received PEM and 30 CM. Both groups were statistically similar as to age (67 vs 70 years), sex (57% vs 30%), SBP (157 vs 156 mmHg) and DBP (88 vs 88 mmHg), proportion of diabetes (23% vs 31%) and basal natriuresis (116 vs 121 meq/day). SBP fell in both groups over the study period. At 3 months the PEM group showed a significant reduction of 8.45 mmHg (95% CI 1.7–15.0), while CM had 2.60 mmHg (95% CI –3.09 to 8.29), with a net reduction of –5.85 (95% CI –14.40 to 2.70). Mean net nighttime SBP reduction was –12.40 (95% CI –22.40 to –2.40).

The relative odds ratio for BP control for the PEM group after adjustment for age, sex, diabetes, basal blood pressure, and changes in pharmacological treatment was 3.70 (95% CI 1.05–13.10).

Conclusion: Self-management education model was significantly more effective in blood pressure reduction and increased blood pressure control in elderly patients.

Bread and Cheese: Regular Consumption in Patients from the Italian Consulate in Argentina Cavalieri L, Mollar G, Galarza C, Rada M, Janson J, Petrlik E, Figar S, and Langlois E, Marchetti M. Programas Médicos de Plan de Salud del Hospital Italiano de Buenos Aires

It has been well demonstrated that the hyposodic diet in elderly people is effective to control hypertension. We think that elderly hypertensive and low economic and social status patients find it difficult to detect “hidden” salt in food.

Objective: To know the intake frequency and the knowledge about salt content and healthy food in elderly hypertensives.

Methods: A total of 60 hypertensive patients, older than 65 years old, without psychiatric disorders, members of our HMO were evaluated. The intake frequency of bakery products, cheese, bread, and healthy food during the previous week was evaluated through a self-administered questionnaire in which answers were expressed in Likert ordinal scale. The survey took place before a workshop for hypertensive patients as part of our Anti hypertensive Intervention Program. The study design was Cross-sectional.

Results: The mean age was 65.43 years (SD 17.48), and mean education level was 6.3 years (SD 3.1). The proportion of diabetes was 28%, and 43% were women. The SBP was 156.8 mm Hg (SD 14) and the DBP was 87.7 mm Hg (SD 9).

Among 60 patients recruited, 55 (91.65 %) consumed bread during the previous week, and 69% of those had high frequency intake; 51 patients (80%) consumed cheese. Bread was recognized as having high content of salt by 80%, Mar del Plata cheese by 85%, Port salut cheese by 35%, croissants 63,3%, cookies by 11% and crackers by 35%.

Fully 85% of patients recognize food rich in sodium by its flavor. Only 10% of patients look at labels in the products they buy. Only 3 patients were aware of the maximum sodium content acceptable for a hyposodic diet.

Discussion: These patients recognize bread and cheese as high level sodium food. However, their intake is frequent. These patients recognize salty food through flavor, and very few patients read labels on packages. Their intake of salt is high particularly through sweet tasting meals. Knowing patients social and economic status, and their dietary sodium consumption, we can find better strategies to educate hypertensive patients about hyposodic diet.

Conclusion: Although the patients have knowledge about high level sodium food, the intake frequency of bakery products and cheese is high. Also, healthy food intake is very poor.

Elderly Hypertensive Patients under a Disease Management Program for Hypertension: a Follow-up Study Díaz Seoane D, Galarza C, Waisman G, Figar S, Langlois E, Marchetti M, and Gonzalez B de Quirós F Programas Médicos de Plan de Salud del Hospital Italiano de Buenos Aires

Even when effective treatment is available for hypertensive patients, control levels are below those expected and desired. To tackle this problem Plan de Salud del Hospital Italiano de Buenos Aires launched, in August 2000, a disease management program oriented to hypertensive patients. With the aim of assessing follow up parameters of patients included in the program, we designed the present prospective cohort study.

Methods: First, 5488 patients were recruited in the program during 2000. Follow-up was undertaken until death, cardiovascular event, disaffiliation, or end of the study in December 2004. Main outcome measures were: risk of dying, risk of being admitted to our hospital, mean difference in blood pressure at the recruitment vs. last available, and proportion of well-controlled patients (BP < 140/90). Our data source was electronic medical records.

Intervention was participation and commitment of advanced medical students who measured and recorded vital signs in EMR periodically since the recruitment and gave patients advice on healthy lifestyle. They invited them to participate in educational workshops. Rates are expressed per 1000 person-years and their 95% Confidence interval (CI).

Results: Mean age 75 (SD 5.5), 67% females, mean follow-up 43 months. Admission rate 84 (81–88), cardiovascular event rate 13 (95% CI 11.3–14.5) stroke rate 5.3 (95% CI 4.4–6.5), and overall mortality rate 23 (95% CI 21–25). Baseline blood pressure was 135.9/74 mmHg and final BP was 136.7/76 mmHg. Proportion of well-controlled patients was 59% at baseline; it was 54% at last visit, being 34% for those who were controlled at baseline and 46% for those who were uncontrolled at baseline (p < 0.01).

Discussion: It is well known that blood pressure naturally increases with age. In our cohort mean increase in age was 4 years while SBP and DBP increased 0.75 and 2 mmHg respectively. Losses to follow-up of only 13% is acceptable and are unlikely to bias result. However, 23.5% of patients did not have blood pressure recorded during 2004 (due to death, inability to contact them, or others). This fact makes it difficult to generalize results on final blood pressure control to the whole cohort. Achievement of control was higher in those initially uncontrolled. This might be because the program emphasized intervention on uncontrolled patients.

Conclusion: Elderly hypertensive patients present high mortality and admission rates after 4 years of follow-up, without wide changes in blood pressure.

Measurement of Soluble Cd44 in Arterial Hypertensive Patients D’Arrigo M,² Filippini F², Lebensohn N¹, Barberena L², Gallo R², Valverde J, and Foresto P^{1 1}Departamento Bioquímica Clínica, Laboratorio de Inmunohematología, Fac. de Cs. Bioquímicas y Farmacéuticas, IFIR (CONICET-UNR). ²Clínica Médica, Facultad de Cs, Médicas, UNR, Rosario

CD44 is a broadly distributed cell surface glycoprotein implicated in multiple physiologic cellular functions including cell-cell adhesion and involved in immune stimulation and signaling between cells. It is commonly referred to as CD44 and has been shown to be a major cell surface receptor for hyaluronate.

Objective: To develop a simple technique for the study of soluble erythrocyte hyaluronate (CD44) receptor expression in serum from healthy adult subjects and arterial hypertensive patients.

Methods: The interaction between red blood cells (RBC), (CD44) receptor, and its ligand (hyaluronate) is studied by inhibition agglutination test. Samples of anticoagulated blood from healthy adult subjects (n = 13) and arterial hypertensive patients (n = 20) were used.

Several dilutions of serum in phosphate saline buffer pH 7.4 were confronted with an equal volume of hyaluronate in optimal concentration (1/256) and incubated 15 min at 4 °C. A 2% bromelinized erythrocyte suspension was used as a revealing system. The RBC were added and incubated at 4 °C for 24 h. The evaluation was made, observing specific aggregation of the cells. To estimate the grading reactions we have used a numeric parameter: sensibility parameter (α).

Results: Expressed through the sensibility parameter, that involves titer and score. α is defined by mathematical expression: α = Σ S_i, D⁻¹_i, 10⁻ (Di = 1, 2, 3, …), where S_i represent the score and D_i⁻¹ is the inverse of dilution.

The results are expressed as ξ ± SD. The Mann Whitney test was used to compare two independent samples. The healthy subjects RBC showed α = 1.07 ± 0.35, whereas in the hypertensive patients the parameter was α = 1.33 ± 0.25. Our results showed significant differences between both groups.

Conclusion: We present a simple technique to estimate the soluble hyaluronate (CD44) receptor, which could be a useful tool to study the alterations of the receptor’s expression in RBCs.

Apolipoprotein E (Apoe): Allelic Frequency in a Pediatric Population D’Arrigo M,¹ Lioi S,¹ Pituelli N,¹ Corbera M,¹ Turco M,¹ Beloscar J,² Gastaldi L,² and Rosillo I^{1 1}Area Química Analítica, Depto de Bioquímica Clínica, Fac.de Cs. Bioq. y Farm, UNR ²Carrera de Cardiología, Facultad de Ciencias Médicas, UNR

Cardiovascular disease (CVD) is a frequent atherosclerosis complication with high morbidity and mortality incidence. ApoE is a polymorphic glycoprotein playing a critical role in cholesterol homeostasis and lipoprotein rich in triglycerides. Several studies have demonstrated a relationship between apoE alleles and atherosclerosis development, ischemic coronary disease, and stroke. Since there is an association with lipid levels there are different studies dealing with the relationship between apoE genotype and cardiovascular disease. The association between ε4 and coronary disease has been widely discussed. The presence of apoE polymorphism is considered a CVD risk factor, determined either through lipid plasma concentration or through mechanisms not completely understood, but probably related to atherosclerosis and therefore present from the early stages of life. Former facts added to positive family history of coronary disease provides this genotype with an important predictive and preventive capacity in CVD.

Objective: The apoE genotyping is of the utmost importance, and since there are no local statistical studies on the apoE allele frequency, we carried out the study of the apoE genotype frequency—predictor of coronary disease—in a pediatric population. This genetic study could provide a piece of information to identify individuals, relatives and populations with increased CVD risk. Participants: children, both sexes, aged 6–14 years, were randomly recruited pondering a sample (n = 56) of the population under study to estimate e2, e3, and e4 allele frequency. The sample size was statistically calculated to obtain a representative estimation of the whole population considering a 95% confidence interval (CI).

Methods: DNA extraction with DNA Purification Kit Wizard Genomic was performed on blood samples with EDTA as anticoagulant. Genotyping was determined by PCR amplification of a DNA fragment coding for part of apoE gene that includes mutations defining the genotype. The allele identification was performed on agarose gel electrophoresis. The Ethical Committee of Facultad de Bioquímica, UNR, approved the present work and the parent or tutor participant signed of informed consent.

Results: The allelic frequencies in the population were e3: 0.786 (95% CI 0.679–0.893); e4: 0.178 (95% CI, 0.078–0.278) and e2: 0.036 (95% CI, 0.000–0.084). Hypothesis test admitting normal distribution was performed to assess comparison of the sample allelic frequency with the international reference values. No significant differences were observed in apoE alleles among different populations. In the local population, e3 allele frequency is significantly higher than e2 and e4, which is coincident with the international literature.The characteristics of our population enabled us to examine the apoE allelic frequency at an age in which the environmental factors or adult lifestyle, such as tobacco, alcohol, etc. are absent, thus minimizing the number and weight of risk factors.

Conclusion: The identification of the genetic load at early age might encourage children to adopt behavior patterns (food habits, physical activity, etc) contributing to prevent and control its impact and the occurrence of other CVD risk factors.