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Biomedical subjects

L Prieto

Publications and source records attributed to L Prieto.

At least 55 records · Page 3Linked to original sources
PubMed2000

Airway responsiveness to acetaldehyde in patients with asthma: relationship to methacholine responsiveness and peak expiratory flow variation.

BACKGROUND: Although airway hyperresponsiveness to inhaled acetaldehyde has been documented in Japanese patients with asthma, the response to this bronchoconstrictor agent has never been studied in Caucasians. OBJECTIVES: The objectives of the study were to determine differences in airway responsiveness to acetaldehyde between asthmatic and healthy subjects, and to examine the relationship between acetaldehyde responsiveness and the variability of peak expiratory flow (PEF). METHODS: The response to methacholine and acetaldehyde challenges was measured in 81 non-smoking adults (61 asthmatics and 20 normal controls). Subjects recorded PEF morning and evening for 14 days. The response to both bronchoconstrictor agents was measured by the PC20 (provocative concentration required to produce a 20% fall in FEV1). PEF variation was expressed as amplitude percentage mean, and as low percentage best (lowest PEF expressed as a percentage of the best PEF recorded). RESULTS: The two types of challenge yielded a similarly high level of sensitivity (100% for methacholine and 92% for acetaldehyde) and specificity (90 and 100%, respectively) to distinguish between asthma and controls. Asthmatic subjects were on average 265-fold less sensitive to acetaldehyde than to methacholine. PC20 acetaldehyde correlated weakly but significantly with both indices of PEF variation (amplitude percentage mean: rho = - 0.36, P = 0. 004; low percentage best: rho = 0.42, P = 0.001). CONCLUSIONS: These results indicate that airway hyperresponsiveness to acetaldehyde is a sensitive and specific indicator for separating asthmatic and normal subjects. Airway responsiveness to methacholine or acetaldehyde and PEF variation are not reflecting the same pathophysiological process in the airways.

Acetaldehyde↗
PubMed2000

Exploring health preferences in sociodemographic and health related groups through the paired comparison of the items of the Nottingham health profile.

BACKGROUND: Preference weighted measures of health related quality of life are necessary for cost effectiveness calculations involving quality of life adjustment. There are conflicting data about the influence of factors such as sociodemographic and health related variables on health preferences. STUDY OBJECTIVE: The relative values attached to the items of the Spanish version of the Nottingham Health Profile (NHP) were assessed to make comparisons across social and health subgroups. DESIGN AND PARTICIPANTS: Preference values were obtained in sets of 250 to 253 persons (total n=1258) using the method of paired comparisons after all possible pairs of NHP items had been presented to respondents for judgement of severity. chi(2) Tests and Spearman's correlations among item ranks were calculated. MAIN RESULTS: Findings show that preferences elicited with the method of paired comparisons are consistent and independent of the sample from which they are obtained (mean correlation coefficients across subgroups range from 0.87 to 0.96). Conclusion-The evaluation of health did not seem to be related to sociodemographic variables (gender, age, social class) or to the health status of the respondents, suggesting that health preferences are stable across different populations.

Adult↗
PubMed2000

Usefulness of thyroxine and free thyroxine filter paper measurements in neonatal screening for congenital hypothyroidism of preterm babies.

INTRODUCTION: Low thyroxine (T4) with normal thyroid stimulating hormone (TSH) is a well known condition in preterm (PT) infants. The establishment of T4 and freeT4 (FT4) values in filter paper dried blood spots in PT could provide useful information in the neonatal period. OBJECTIVE: To study T4 and FT4 levels in dried blood filter paper samples of PT and full term (FT) babies. METHODS: We measured T4 by fluoroimmunoassay (FIA) DELFIA and TSH by IFMA DELFIA (Wallac Inc Turku, Finland) in 193 PT (26 to 37 weeks of gestational age (GA)) in samples from the first and second week of life and in 153 FT babies in the first week of life. In 131 PT and 31 FT we determined FT4 in filter paper blood spots using FIA (Alonso Fernandez J). Infants were grouped according to GA. RESULTS: There was a significant difference in T4 between PT and FT (p < 0.001). The lowest T4 levels were at 26 to 29 weeks GA. T4 values were lower in the second week. FT4 in PT up to 35 weeks GA, during the first week, was significantly different with FT infants (G1 to G3 p < 0.01, G4 p < 0.05). FT4 values in the first and second weeks of life did not vary. CONCLUSIONS: T4 values were significantly lower in PT than in FT neonates, increasing with GA. PT infants had low T4 with normal FT4 values. This could suggest a decreased thyroxine binding globulin (TBG) or decreased protein binding and/or an adaptative mechanism that would not require therapeutical intervention.

Congenital Hypothyroidism↗
PubMed2000

[Development of the ECOS-16 clinical questionnaire for the assessment of the quality of life in patients with osteoporosis].

BACKGROUND: The use of currently validated instruments to measure the health-related quality of life (HRQoL) of patients with osteoporosis in daily clinical practice is not feasible due to the length of time needed to be administered. The objective of the present study was to develop a new, short questionnaire for women with vertebral fractures due to osteoporosis. PATIENTS AND METHODS: The administration of two disease-specific questionnaires (OQLQ and QUALEFFO) and the generic SF-36 questionnaire to 338 women with vertebral fracture due to osteoporosis allowed the development of a new questionnaire in 5 stages: i) search for a common structure in both questionnaires; ii) independent reduction of items in the OQLQ and QUALEFFO using Rasch analysis; iii) aggregation of remaining items in both questionnaires into distinct dimensions; iv) quantitative reduction of redundant items in aggregated dimensions; v) qualitative item reduction in aggregated scales. RESULTS: The methodology of the study allowed the development of a 16 item questionnaire (ECOS-16), with 4 items taken from the OQLQ and 12 from the QUALEFFO. The items are grouped into 4 categories: physical functioning (5 items), illness-related fears (2 items), psychosocial functioning (4 items), and pain (5 items). CONCLUSIONS: The ECOS-16 will be a promising alternative, once it is validated, to generic questionnaires and to the specific questionnaires from which its content was extracted, particularly for patients with osteoporotic vertebral fracture in daily clinical practice.

Aged↗
PubMed1999

Relationship between induced sputum cell counts and fluid-phase eosinophil cationic protein and clinical or physiologic profiles in mild asthma.

BACKGROUND: Sputum analysis is the only non-invasive method to examine airway inflammatory processes in subjects with asthma. The aim of this study was to investigate the relationship between cell counts and fluid phase levels in induced sputum in subjects with mild asthma, and the severity of asthma as assessed by clinical, physiologic and blood measurements. METHODS: Forty patients with mild asthma, aged 17 to 49 years were studied (good sputum sample only from 31). On the first day, spirometry and methacholine challenges were performed. After 2 to 4 days, venous blood for absolute eosinophil count and eosinophil cationic protein (ECP) measurement was obtained and sputum was induced by inhalation of hypertonic saline. For the next 15 days subjects recorded their peak expiratory flow (PEF), symptom scores, and beta2-agonist requirements twice daily. Differential counts of leukocytes were done on cytospin preparations of homogenized sputum and the supernatant was examined for eosinophil cationic protein (ECP). RESULTS: Sputum eosinophil counts and not neutrophil, epithelial cells, macrophages, or lymphocytes, were inversely correlated to FEV1/FVC % (r = -.57, P = .0008) and to PC20-methacholine (r = -.40, P = .024). No statistical relationship was obtained between eosinophil counts and either symptom scores, bronchodilator requirements, or daily PEF variability. Sputum ECP values were correlated to FEV1/FVC% (r = -.41, P = .026) but not to PC20 (r = -.32, P = .08) or clinical scores or PEF variation. A trend to significance was appreciated between peripheral blood and sputum eosinophil counts (r = .34, P = .067) and no relationship was found between sputum and serum ECP values (r = .10, P = .38). CONCLUSIONS: Although sputum markers give some information about disordered lung function and physiologic changes in the airways, they are not the only factors concerned in the clinical expression of mild asthma.

Adolescent↗
PubMed1999

The QoL-AGHDA: an instrument for the assessment of quality of life in adults with growth hormone deficiency.

Several studies have shown that growth hormone deficiency in adults leads to poor well-being and other clinical consequences, and that these improve when the hormone is replaced. However, the studies employed generic measures of health status that miss important aspects of the patients' experience and that have inadequate reliability and responsiveness. This paper describes the European development and testing of the Quality of Life-Assessment of Growth Hormone Deficiency in Adults (QoL-AGHDA), a condition-specific quality of life measure for use in clinical trials and for the routine monitoring of patients. The instrument was produced in five languages; English, Swedish, Italian, German and Spanish. Each language version is shown to have good reliability, internal consistency and construct validity. The QoL-AGHDA is currently included in an international database monitoring the long-term efficacy and safety of growth hormone replacement therapy and in clinical trials in a number of countries.

Adult↗
PubMed1999

A new measure for assessing the health-related quality of life of patients with vertigo, dizziness or imbalance: the VDI questionnaire.

Vertigo, dizziness and imbalance are frequent symptoms among patients in clinical practice. We present the development of a new multipurpose measure specific to patients with these symptoms: the VDI questionnaire. Items of the VDI questionnaire were generated through an international panel of clinicians, in-depth interviews with 25 patients and an extensive literature search. Items were reduced by qualitative and quantitative methods. Psychometric properties were tested in 130 patients recruited in primary care general practices, neurologists and ENT out-patient clinics. Patients were clinically evaluated and administered several specific and generic health status instruments: the Balance Scale, the SF-12 Health Survey and the General Health Questionnaire 12 items. The VDI symptoms and the VDI health related quality of life (HRQoL) scales were administered during the visit and some weeks after. Correlation and confirmatory factor analysis were used. Reliability of the VDI was high (0.92 for VDI HRQoL scale and 0.86 for VDI symptoms). VDI scores were more correlated with Balance Scale scores than with mental health indicators. All factor loadings were significantly different from zero and confirmed the expected relations. In the second administration, VDI scores showed a deterioration among those reporting a worsening in their symptoms and an improvement among those reporting feeling better. The data presented suggest that the VDI questionnaire is a reliable, valid and responsive instrument for patients with vertigo, dizziness or imbalance. The VDI questionnaire could be a useful complement of the clinical evaluation of these patients at both group and individual level.

Activities of Daily Living↗
PubMed1999

Maximal response plateau to methacholine as a reliable index for reducing inhaled budesonide in moderate asthma.

Although some studies suggest that asthma deteriorates after reducing inhaled steroids, results of long-term studies indicate that this might not be true for all patients. The aim of this study was to determine the utility of the detection of a plateau on the concentration-response curves to inhaled methacholine as a marker for safely reducing the dose of inhaled budesonide in asthmatic patients who are well-controlled with a moderately high dose of this inhaled steroid. A total of 46 patients with moderate asthma, well-controlled for at least 6 months by treatment with 800 microg budesonide daily, were included in the study. Subjects were treated for a 2-week run-in period with their usual dose of budesonide. At the end of the run-in, all subjects were challenged with methacholine (0.095-200 mg x mL(-1)). Plateau responses, median effective concentration values, slopes and provocative concentration of methacholine causing a 20% fall in forced expiratory volume in one second (FEV1) values were measured. For the subsequent 12 weeks, patients were treated in an open design with budesonide at a reduced dose (200 microg once daily), and were asked to record their peak expiratory flow (PEF) in the morning and in the evening. In addition, asthma symptoms and use of rescue terbutaline were recorded in diaries. Plateaus were present in 24 patients, whereas 22 subjects showed concentration-response curves without evidence of a plateau. Ten patients in the nonplateau group deteriorated after reducing inhaled budesonide, compared to one patient in the plateau group (p = 0.002). In the nonplateau group, FEV1 decreased from a baseline value of 3.28+/-0.19 L to 2.94+/-0.20 L at week 12 (p<0.0001). Likewise, morning PEF decreased from 419+/-19 L x min(-1) at baseline to 394+/-19 L x min(-1) at week 12 (p = 0.02). By contrast, these variables remained unchanged in the plateau group. In conclusion, in asthmatic patients, well-controlled with a moderately high dose of budesonide, the detection of a plateau on the concentration-response curve to inhaled methacholine may be used as a marker for safely reducing the corticosteroid dose.

Administration, Inhalation↗
PubMed1998

[Population reference values of the Spanish version of the Health Questionnaire SF-36].

BACKGROUND: Perceived health status measurements reference values an important information source for health services research. Population-based norms have been proposed to increase their interpretability. In this paper, we have obtained the norms of the Spanish version of the SF-36 Health Survey and have compared them with US norms the questionnaire. MATERIAL AND METHODS: Data were obtained in the home interview survey on drug consumption (February 1996). This is a cross-sectional study of a multi-stage, stratified random sample of non-institutionalized individuals 15 and older residents in Spain. The final sample included 9,984 individuals, but the analysis is based on those individuals 18 or older (n = 9,151). Personal home interviews were carried out. Information included: the SF-36, legal and illegal drugs consumption, and socio-demographic data, among others. Central trend and dispersion statistics were estimated for each of the SF-36 dimension scores according to gender and age group. Cronbach's alpha coefficients were calculated to estimate the reliability of scores. RESULTS: For most SF-36 dimensions, scores were higher (better) among men and among younger age groups (p < 0.01). There was a monotonic score gradient by age which was more intense for physical function and bodily pain. All Cronbach's alpha coefficients were higher than 0.7 (ranging from 0.78 to 0.96). Spanish norms were very similar to those obtained in the US. CONCLUSIONS: Results presented should be considered the population-based norms of the Spanish version of the SF-36 Health Survey and may be useful for interpreting the questionnaire scores. These norms, which are very similar to the original US questionnaire both in absolute values and in the gender and age group distribution patterns, should be carefully used. Considerations for use discussed in the paper should be taken into account.

Adolescent↗
PubMed1998

Epidemiological analysis of outcomes of pregnancy in gestational diabetic mothers.

The association between maternal diabetes mellitus and congenital defects has been well documented. However, few data exist on the potential teratogenic effect of gestational diabetes (GD). We analyzed 19,577 consecutive infants with malformations of unknown cause and compared the offspring of mothers with GD with those of nondiabetic mothers. The children with each of 20 types of selected anomalies among the two groups were used to calculate the odds ratio (OR). Because we used as a reference group for each congenital defect the rest of malformed infants, the value of the OR gives us the specificity between the association of GD and each congenital defect. Our analysis strongly supports the suggestion that GD is a significant risk for holoprosencephaly, upper/lower spine/rib, and renal and urinary system anomalies. GD is a heterogeneous disorder, which includes previously unrecognized and newly diagnosed nongestational diabetes mellitus (DM). Thus, it is possible that the teratogenic effect is related to latent DM. However, because it is not possible at this time to differentiate between these situations, pregnancies complicated by GD should be considered at risk for congenital anomalies. Prenatal ultrasound examination should be aimed particularly at the detection of abnormalities of the central nervous system, the renal and urinary system, and the spine/rib developmental field.

Diabetes, Gestational↗
PubMed1998

Prenatal exposure to sex hormones: a case-control study.

The adverse effect of therapeutic use of sex hormones during pregnancy inducing pseudohermaphroditism in female offspring has been well known since the early 1950s. Consequently there has been great concern about the potential effects on the offspring of women who use these agents during gestation. Some studies have reported an association, particularly of oral contraceptives used during pregnancy, with specific types of congenital defects, while this was not observed in other studies. Here we present the results of a large case-control study on the effect of prenatal exposure to each type of sex hormone. Cases were those malformed infants of unknown cause, that is, excluding syndromes and those cases with defects that have dominant or recessive inheritance, and those due to recognized teratogens. The controls were selected from the same population as the cases and are representative of those who, had they developed malformations, would have been selected as cases. The results, after controlling potential cofounder factors with different logistic regression analyses, do not support the hypothesis that prenatal exposure to sex hormones increases the risk of genital and nongenital malformations.

Abnormalities, Drug-Induced↗