Determinants of left ventricular diastolic dysfunction in hypertensive patients / Factores Asociados a la Disfunción Diastólica del Ventrículo Izquierdo en Pacientes con Hipertensión Arterial

Introduction: The progression of hypertensive heart disease leads to the left ventricular diastolic dysfunction (LVDD), which is associated with increased cardiovascular morbidity and mortality. The purpose of this analysis is to explore the determinants for LVDD in patients with hypertension. Methods: This is a secondary analysis of data of Impedance Cardiography in the Evaluation of Left Ventricular Diastolic Dysfunction in Patients with Arterial Hypertension (IMPEDDANS) Study. Mann-Whitney and Chi-square tests were used for univariable analysis. Multiple logistic regression was used to model for LVDD occurrence and discriminative capacity of the model assessed by the value of the area under the curve given by the receiver-operating characteristic curve. Results: Older age (65 vs. 58 years, p < 0.001), longer duration of hypertension (160 vs. 48 months, p < 0.001), uncontrolled hypertension (59.8 vs. 15.9%, p < 0.001), tobacco smoking (17.8 vs. 3.8%, p = 0.016), higher systolic blood pressure (133 vs. 124 mmHg, p = 0.001) and slower heart rate (62 vs. 66 bpm, p = 0.023) were associated with LVDD. Multivariate model identified uncontrolled hypertension (AdjOR 36.90; 95% CI 7.94-171.58; p < 0.001), smoking (AdjOR 6.66; 95% CI 1.63-27.26; p = 0.008), eccentric hypertrophy (AdjOR 3.59; 95% CI 0.89-14.39; p = 0.072), duration of hypertension (AdjOR 1.03; 95% CI 1.02-1.05; p < 0.001) and concentric remodeling (AdjOR 0.19; 95% CI 0.04-0.93; p = 0.041) as the more determinant for occurrence of LVDD. The discriminative capacity of the model was AUC = 0.95 (95% CI 0.91-0.98). Conclusion: The occurrence of LVDD in hypertensive patients was strongly associated to long-lasting, uncontrolled hypertension, tobacco smoking, concentric remodeling and eccentric hypertrophy

Introducción: La progresión de la enfermedad cardiaca hipertensiva produce disfunción diastólica del ventrículo izquierdo (DDVI) y aumento de morbilidad y mortalidad. El objetivo de este estudio es evaluar los factores que se asocian a la DDVI en pacientes con hipertensión arterial. Métodos: Se trata de un análisis secundario del estudio IMPEDDANS. Se utilizaron las pruebas de la U de Mann-Whitney y la Chi-cuadrado para el análisis univariado, y posteriormente se realizó un análisis de regresión logística multivariado. La capacidad discriminativa del modelo fue evaluada por el valor del área bajo la curva (ABC) dada por la curva característica de funcionamiento del receptor. Resultados: Los pacientes con DDVI eran mayores (65 vs. 58 años; p < 0,001), tenían historia previa de hipertensión arterial más larga (160 vs. 48 meses; p < 0,001), presentaban frecuentemente hipertensión arterial no controlada (59,8 vs. 15,9%; p < 0,001), fumaban más (17,8 vs 3,8%; p = 0,016), presentaban presión arterial sistólica más alta (133 vs. 124 mmHg; p = 0,001) y frecuencia cardiaca más lenta (62 vs. 66 pm; p = 0,023). En el modelo multivariado se objetivó hipertensión no controlada (OR 36,90; IC 95% 7,94-171,58; p < 0,001), hábito tabáquico (OR 6,66; IC 95% 1,63-27,26; p = 0,008), hipertrofia excéntrica (OR 3,59; IC 95% 0,89-14,39; p = 0,072), la duración de la hipertensión (OR 1,03; IC 95% 1,02-1,05; p < 0,001) y remodelado concéntrico (OR 0,19; IC 95% 0,04-0,93; p = 0,041) eran factores asociados a la DDVI. La capacidad discriminativa del modelo se correspondió con un ABC = 0,95 (IC 95% 0,91-0,98). Conclusión: El desarrollo de la DDVI en pacientes con hipertensión arterial se asoció a la duración de la hipertensión, la hipertensión no controlada, el hábito tabáquico, el remodelado concéntrico y la hipertrofia excéntrica

Determinants of left ventricular diastolic dysfunction in hypertensive patients.

INTRODUCTION: The progression of hypertensive heart disease leads to the left ventricular diastolic dysfunction (LVDD), which is associated with increased cardiovascular morbidity and mortality. The purpose of this analysis is to explore the determinants for LVDD in patients with hypertension. METHODS: This is a secondary analysis of data of Impedance Cardiography in the Evaluation of Left Ventricular Diastolic Dysfunction in Patients with Arterial Hypertension (IMPEDDANS) Study. Mann-Whitney and Chi-square tests were used for univariable analysis. Multiple logistic regression was used to model for LVDD occurrence and discriminative capacity of the model assessed by the value of the area under the curve given by the receiver-operating characteristic curve. RESULTS: Older age (65 vs. 58 years, p<0.001), longer duration of hypertension (160 vs. 48 months, p<0.001), uncontrolled hypertension (59.8 vs. 15.9%, p<0.001), tobacco smoking (17.8 vs. 3.8%, p=0.016), higher systolic blood pressure (133 vs. 124mmHg, p=0.001) and slower heart rate (62 vs. 66bpm, p=0.023) were associated with LVDD. Multivariate model identified uncontrolled hypertension (AdjOR 36.90; 95% CI 7.94-171.58; p<0.001), smoking (AdjOR 6.66; 95% CI 1.63-27.26; p=0.008), eccentric hypertrophy (AdjOR 3.59; 95% CI 0.89-14.39; p=0.072), duration of hypertension (AdjOR 1.03; 95% CI 1.02-1.05; p<0.001) and concentric remodeling (AdjOR 0.19; 95% CI 0.04-0.93; p=0.041) as the more determinant for occurrence of LVDD. The discriminative capacity of the model was AUC=0.95 (95% CI 0.91-0.98). CONCLUSION: The occurrence of LVDD in hypertensive patients was strongly associated to long-lasting, uncontrolled hypertension, tobacco smoking, concentric remodeling and eccentric hypertrophy.

The effect of long-chain polyunsaturated fatty acids intake during pregnancy on adiposity of healthy full-term offspring at birth.

OBJECTIVE: The adjusted effect of long-chain polyunsaturated fatty acid (LCPUFA) intake during pregnancy on adiposity at birth of healthy full-term appropriate-for-gestational age neonates was evaluated. STUDY DESIGN: In a cross-sectional convenience sample of 100 mother and infant dyads, LCPUFA intake during pregnancy was assessed by food frequency questionnaire with nutrient intake calculated using Food Processor Plus. Linear regression models for neonatal body composition measurements, assessed by air displacement plethysmography and anthropometry, were adjusted for maternal LCPUFA intakes, energy and macronutrient intakes, prepregnancy body mass index and gestational weight gain. RESULT: Positive associations between maternal docosahexaenoic acid intake and ponderal index in male offspring (ß=0.165; 95% confidence interval (CI): 0.031-0.299; P=0.017), and between n-6:n-3 LCPUFA ratio intake and fat mass (ß=0.021; 95% CI: 0.002-0.041; P=0.034) and percentage of fat mass (ß=0.636; 95% CI: 0.125-1.147; P=0.016) in female offspring were found. CONCLUSION: Using a reliable validated method to assess body composition, adjusted positive associations between maternal docosahexaenoic acid intake and birth size in male offspring and between n-6:n-3 LCPUFA ratio intake and adiposity in female offspring were found, suggesting that maternal LCPUFA intake strongly influences fetal body composition.

Resting energy expenditure, macronutrient utilization, and body composition in term infants after corrective surgery of major congenital anomalies: A case-study.

INTRODUCTION: Knowledge on the metabolic changes and nutritional needs during the postsurgical anabolic phase in infants is scarce. This analysis explores the associations of resting energy expenditure (REE) and macronutrient utilization with body composition of full-term infants, during catch-up growth after corrective surgery of major congenital anomalies. METHODS: A cohort of full-term appropriate for-gestational-age neonates subjected to corrective surgery of major congenital anomalies were recruited after gaining weight for at least one week. REE and macronutrient utilization, measured by respiratory quotient (RQ), were assessed by indirect calorimetry using the Deltatrac II Metabolic Monitor ®. Body composition, expressed as fat-free mass (FFM), fat mass (FM) and adiposity defined as percentage of FM (% FM), was measured by air displacement plethysmography using the Pea Pod ®. RESULTS: Four infants were included at 3 to 5 postnatal weeks. Recommended energy and macronutrient intakes for healthy term infants were provided. Through the study, the median (min-max) REE (Kcal/Kg FFM/d) was 70.8 (60.6-96.1) and RQ was 0.99 (0.72-1.20). Steady increases in both body weight and FFM were associated with initial decrease in FM and adiposity followed by their increase. Low RQ preceded decrease in adiposity. CONCLUSION: The marked adiposity depletion, not expected during steady weight gain in the postsurgical period, prompts us to report this finding. The subsequent adiposity catch-up was associated with relatively high REE and RQ, suggesting preferential oxidation of carbohydrates and preservation of lipids for fat storage.

Early high calcium and phosphorus intake by parenteral nutrition prevents short-term bone strength decline in preterm infants.

BACKGROUND AND AIM: Very premature newborns have an increased risk of low bone mass and metabolic bone disease. Most longitudinal studies report a significant decline in bone strength in the first weeks after birth. The aim of the study was to evaluate whether higher early calcium (Ca) and phosphorus (P) intake delivered by parenteral nutrition (PN) can prevent bone strength decline in preterm infants, within the first weeks after birth. PATIENTS AND METHODS: This was a randomized controlled trial of consecutively admitted neonates born with ≤ 33 weeks of gestational age, assigned to receive either Ca 45 mg · kg⁻¹ · day⁻¹ (low dose [LD]) or Ca 75 mg · kg⁻¹ · day⁻¹ (high dose [HD]) by PN. P was added to the PN solutions at a fixed Ca:P ratio (mg) of 1.7:1. Bone strength was assessed by the speed of sound (SOS) using the quantitative ultrasound method. Measurements were performed weekly from birth until discharge. Low bone strength (SOS < 10th centile of reference values) was the main outcome. RESULTS: Eighty-six infants were enrolled, 40 assigned to LD group and 46 to HD group. Mean (standard error) gestational age was 29.6 weeks (2.1) and birth weight was 1262 g (0.356). In the HD group, the SOS values never fell below those recorded at birth and, up to the sixth week of life, low bone strength was significantly less frequent as compared with that in the LD group, in spite of progressive reduction in parenteral mineral intake and/or establishment of full enteral feeding. CONCLUSIONS: Early assigned parenteral intake of Ca 75 mg · kg⁻¹ · day⁻¹ and P 44 mg · kg⁻¹ · day⁻¹ significantly contributed to preventing short-term bone strength decline in preterm infants.

Upper arm anthropometry is not a valid predictor of regional body composition in preterm infants.

BACKGROUND: Upper arm anthropometry has been used in the nutritional assessment of small infants, but it has not yet been validated as a predictor of regional body composition in this population. OBJECTIVE: Validation of measured and derived upper arm anthropometry as a predictor of arm fat and fat-free compartments in preterm infants. METHODS: Upper arm anthropometry, including the upper arm cross-sectional areas, was compared individually or in combination with other anthropometric measurements, with the cross-sectional arm areas measured by magnetic resonance imaging, in a cohort of consecutive preterm appropriate-for-gestational-age neonates, just before discharge. RESULTS: Thirty infants born with (mean +/- SD) a gestational age of 30.7 +/- 1.9 weeks and birth weight of 1,380 +/- 325 g, were assessed at 35.4 +/- 1.1 weeks of corrected gestational age, weighing 1,785 +/- 93 g. None of the anthropometric measurements are reliable predictors (r(2) < 0.56) of the measurements obtained by magnetic resonance imaging, individually or in combination with other anthropometric measurements. CONCLUSION: Both measured anthropometry and derived upper arm anthropometry are inaccurate predictors of regional body composition in preterm appropriate-for-gestational-age infants.

Osmolality of elemental and semi-elemental formulas supplemented with nonprotein energy supplements.

BACKGROUND: Elemental and semi-elemental formulas are used to feed infants with short bowel syndrome, who may not be able to tolerate feeds of more than 310 mOsm kg(-1). The present study aimed to measure the osmolality of elemental and semi-elemental formulas at different concentrations, with and without the addition of nonprotein energy supplements. METHODS: The osmolality of one elemental and three semi-elemental formulas was measured by the freezing point depression method at concentrations of 10, 12, 14 and 16 g per 100 mL, with and without 10% or 20% of additional calories, in the form of glucose polymers and medium chain triglycerides. Inter-analysis and intra-analysis coefficients of variation of the measurements were less than 3.9%. RESULTS: The mean osmolalities of formulas reconstituted up to 12 g per 100 mL did not exceed 305.3 mOsm kg(-1), even with added energy supplements. The mean osmolalities of formulas at 14 and 16 g per 100 mL, with or without added energy supplements varied between 205.8 and 421.6 mOsm kg(-1). CONCLUSIONS: A comprehensive list of elemental and semi-elemental formulas at different concentrations, enriched or not with calories, is made available. This will enable professionals to customize feeds with the optimum composition, without exceeding the osmolality suggested for infants with short bowel syndrome.

Osmolality of preterm formulas supplemented with nonprotein energy supplements.

BACKGROUND: Addition of energy supplements to preterm formulas is an optional strategy to increase the energy intake in infants requiring fluid restriction, in conditions like bronchopulmonary dysplasia. This strategy may lead to an undesirable increase in osmolality of feeds, the maximum recommended safe limit being 400 mOsm/kg. The aim of the study was to measure the changes in osmolality of several commercialized preterm formulas after addition of glucose polymers and medium-chain triglycerides. METHODS: Osmolality was measured by the freezing point depression method. Six powdered formulas with concentrations of 14 g/100 ml and 16 g/100 ml, and five ready-to-feed liquid formulas were analyzed. All formulas, were supplemented with 10% (low supplementation) or 20% (high supplementation) of additional calories, respectively, in the form of glucose polymers and medium chain triglycerides, maintaining a 1:1 glucose:lipid calorie ratio. Inter-analysis and intra-analysis coefficients of variation of the measurements were always < 3.9%. RESULTS: The mean osmolality (mOsm/kg) of the non-supplemented formulas varied between 268.5 and 315.3 mOsm/kg, increasing by 3-5% in low supplemented formulas, and by 6-10% in high supplemented formulas. None of the formulas analyzed exceeded 352.8 mOsm/kg. CONCLUSION: The supplementation of preterm formulas with nonprotein energy supplements with up to 20% additional calories did not exceed the maximum recommended osmolality for neonatal feedings.

Beyond counting cases: public health impacts of national Paediatric Surveillance Units.

Paediatric Surveillance Units (PSUs) have been established in 14 countries and facilitate national, prospective, active surveillance for a range of conditions, with monthly reporting by child health specialists. The International Network of Paediatric Surveillance Units (INoPSU) was established in 1998 and facilitates international collaboration among member PSUs and allows for sharing of resources, simultaneous data collection and hence comparison of data from different geographical regions. The impact of data collected by PSUs, both individually and collectively as members of INoPSU, on public health outcomes, clinical care and research is described.

Use of palivizumab to control an outbreak of syncytial respiratory virus in a neonatal intensive care unit.

To evaluate the safety and effectiveness of a humanized respiratory syncytial virus (RSV) monoclonal antibody (palivizumab) to control an outbreak of RSV in a neonatal intensive care unit (NICU), we retrospectively analysed two RSV outbreaks. Between 11 November 1998 and 18 March 1999, two separate RSV outbreaks occurred in a large (26 beds) NICU. All procedures for preventing nosocomial spread of RSV (including the use of palivizumab in the second outbreak) were retrospectively analysed. The cumulative incidence (CI), secondary attack rate (SAR) and risk ratio of infection were determined before and after the use of palivizumab for all patients and for those with gestational age below and above 32 weeks in the NICU during the second outbreak. Standard infection control measures were effective in the first outbreak (three cases). In the second outbreak, after three index cases, five additional infants were newly RSV-infected within one month. Three infants had RSV pneumonia and required mechanical ventilation; one infant died. Standard infection control procedures were initiated from the beginning of this outbreak. Palivizumab was given to all infants in the NICU after the fifth case was identified. CI was 2.4% in the first 15 days and 10.5% in the second, and SAR was 2.9 per thousand in the first 15 days and 14.1 per thousand in the second, both dropping to zero after the administration of palivizumab. The risk ratio of infection was 4.65 times higher in infants under 32 weeks gestational age. After the use of palivizumab, there were no additional identified cases. In addition to careful infection control procedures, the use of palivizumab might have contributed to arresting the outbreak of RSV infection in the NICU, suggesting that it could be an additional resource in the control of severe nosocomial RSV outbreaks.

A simple equation to estimate the osmolarity of neonatal parenteral nutrition solutions.

UNLABELLED: A predictive equation of osmolarity that correlates closely with the measured osmolality was determined. Taking into account that an osmometer is not available in most clinical settings, the proposed equation appears to provide a quick and simple osmolarity calculation of neonatal parenteral nutrition solutions. OBJECTIVE: We measured the osmolalities of neonatal parenteral nutrition (PN) solutions to determine if these values may be predicted by a simple equation for calculation of their osmolarity values. METHODS: The osmolalities of 101 consecutive different final PN admixtures, prepared for 36 neonates, were measured by the freezing point depression method. The respective intra-assay and interassay coefficients of variation were always <2.1%. Linear multivariate regression analysis was used to determine a predictive equation of osmolarity that correlates closely with the value of measured osmolality. RESULTS: The mean (SD) osmolality of the final PN admixtures was 749.7 (165.4) mOsm/kg. The best-fitted equation, with a coefficient of discrimination R2 = .95 (R2 = .90 for samples between 500 and 1000 mOsm/L) is osmolarity (mOsm/L) = (nitrogen x 0.8) + (glucose x 1.235) + (sodium x 2.25) + (phosphorus x 5.43)-50, with the concentration of components in mmol/L. Adapting the equation in our daily practice, using g/L for glucose and amino acids, mg/L for phosphorus, and mEq/L for sodium, the equation is osmolarity (mOsm/L) = (amino acid x 8) + (glucose x 7) + (sodium x 2) + (phosphorus x 0.2) - 50, with a similar R2. CONCLUSIONS: Taking into account that an osmometer is not available in most clinical settings, the proposed equation appears to provide a quick and simple osmolarity calculation of neonatal PN solutions, thus allowing more accurate decisions to be taken regarding the choice of route and rate of administration of PN solutions.

Osmolality of solutions, emulsions and drugs that may have a high osmolality: aspects of their use in neonatal care.

OBJECTIVE: Administration of some hypertonic substances to neonates has been associated with a variety of adverse effects. This study was conducted to determine the osmolality of intravenous drugs and solutions used in neonates receiving intensive care. METHODS: Osmolality was measured by freezing point depression. Vasoactive drugs, diuretics, anticonvulsants, antimicrobials, and glucose and electrolyte solutions were some of the substances analyzed. RESULTS: The osmolalities of 90 substances were measured; the respective intra-assay and interassay coefficients of variation were always less than 5%. A few drugs were found to be extremely hypertonic (> 8000 mOsm/kg), and most of them contain propylene glycol as vehicle (e.g. digoxin, phenytoin, diazepam and phenobarbital). Other drugs, at the same concentration, evidenced a significant discrepancy of osmolality depending on the trademark. CONCLUSIONS: The finding of some extremely hypertonic drugs highlights the need for further investigation in order to study their potential adverse effects in neonates, as well as to evaluate any advantage in diluting, infusing slowly or even avoiding such substances. Given the fact that there exists a discrepancy in osmolalities in some drugs at the same concentration depending on the trademark, the more isotonic solutions should be the preferred choice for intravenous administration.

[Prevalence of iron deficiency in early infancy]. / Prevalência da ferropénia na primeira infância.

In order to determine the prevalence of iron deficiency among 6-to-24 month-old children in the Cascais county, a cross-sectional study with systematic opportunist sampling of all 6-to-24-month-old children seen for routine immunization or well-child health care at the Public Health Centers in the Cascais county, during the Spring of 1994. All children were submitted to a short nutritional and clinical inquiry. Blood samples to evaluate anemia and iron deficiency were obtained from eligible children after parental consent. Of the 183 children who visited the health centers during the enrollment period, 125 were eligible for blood sampling. Adequate blood samples were obtained from 120; 38 (31.7%) fulfilled the eligibility criteria for the therapeutical trial (polymaltose-ferric hydroxide, 5 mg/kg/day, for 4 weeks). Twenty-six completed the trial and 13 (50%) had a positive response. The prevalence of iron deficiency estimated for this population sample was 15.8% (CI95% = 8.8-22.3), twice the prevalence of iron deficient anemia, presenting only as mild anemia. Nevertheless, for a total population of 3,500 6-24 month old children in the Cascais area, a 15% prevalence means over 500 iron-deficient children (estimated range between 300 and 800) of which 250 are likely to suffer anemia (150-400) and may be at risk of developing a permanent intellectual deficit. The size of the problem as sampled in the Cascais area does not justify recommending the screening of all young children; instead it points to the need to pay special attention to nutritional education in well-child health care visits, and to allow the early detection and treatment of infants with iron deficiency or at risk of becoming iron deficient.

[Acute meningoencephalitis caused by non-poliomyelitic enterovirus]. / Meningoencefalites agudas por enterovírus não poliomielíticos.

Enterovirus are ubiquitous pathogenic agents, whose only hosts are human. Their protean clinical presentation does not allow an etiological diagnosis grounded only on clinical basis. Despite their known neurotropism, a symptomatic infection of the central nervous system is not the rule. Nevertheless, with the ecological changes induced by the viral vaccines introduced during the last decades and the frequency of infection by these agents, especially among children, non-poliomyelitic enterovirus assume a major role as a cause of viral meningitis and encephalitis in the paediatric age. The epidemiological and clinical context should rule the request of serologic tests to achieve a final diagnosis.