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M Saez

Publications and source records attributed to M Saez.

31 records · Page 2Linked to original sources
PubMed1996

Atopy and nonspecific bronchial responsiveness. A population-based assessment. Spanish Group of the European Community Respiratory Health Survey.

The relative importance of specific immunoresponse in explaining nonspecific bronchial responsiveness (BR) has scarcely been examined. We provide quantitative estimates of the proportion of BR attributable to specific atopy to different common aeroallergens. We used data from a cross-sectional study on a random sample of the general population 20 to 44 yr of age from five Spanish areas. There were 1,816 participants who performed a methacholine challenge and had atopy assessed. BR was defined as a 20% or more fall in FEV1. Atopy was assessed by measuring serum-specific IgE or skin tests to cat, Dermatophagoides pteronyssinus, Cladosporium, Alternaria, timothy grass, olive, birch, Parietaria, or ragweed. The strongest associations between BR and specific IgE response were against timothy grass (prevalence rate ratio = 1.78; 95% confidence interval 1.2 to 2.6), Dermatophagoides pteronyssinus = 1.64 (1.2 to 2.2), and olive = 2.36 (1.5 to 3.7), all after adjustment by age, sex, area of residence, smoking, and a positive response to any of the other eight allergens measured. The population attributable risk of BR for a positive response to any of the nine allergens measured was 20.96% (10.2 to 43.2%) when adjusting for area of residence, age, sex, and smoking. Nonspecific bronchial responsiveness in the general population was found to be related to atopy against single specific allergens, but the population risk attributable to atopy may be lower than previously suggested.

Adult↗
PubMed1995

Relationship between weather temperature and mortality: a time series analysis approach in Barcelona.

BACKGROUND: Many studies have reported that heatwaves increase mortality. However, it is not certain whether less pronounced rises in temperature also increase it. Such information might be important for predicting the impact of potential weather changes on mortality. We have assessed the relationship between daily mortality and moderate increases in weather temperature in Barcelona, Spain, following a time series approach. METHODS: The study included the period from 1 January 1985 to 30 December 1989. For all the population resident in Barcelona, Spain, we considered the following daily data: total mortality, mortality of those > 65 years, and cardiovascular and respiratory mortality. The meterological variables were: minimum temperature, maximum temperature, dew point temperature and relative humidity. Several transfer function (ARIMA) models were estimated for the entire period and for both winters and summers separately. RESULTS: We found that unusual periods of at least three consecutive days of increased weather temperature increased mortality, independently of the V-shaped relationship also found. The occurrence of an unusual period increased total daily mortality by 2% on average (1.7% on summers) and by 2.6% in those over 65 (2% on summers). Cardiovascular mortality rose by 4.6% (4.2% on summers) and respiratory mortality by 21.6% (13.2% on summers). However, only those unusual periods with an excess temperature and humidity were associated with mortality increases. CONCLUSIONS: The unusual periods observed in the present study cannot be classified as heatwaves because the weather temperature never reached high values and most of them occurred during the winter. The association of unusual periods with mortality was stronger during winters than in summers, maybe because unusual winter periods showed a temperature deviation from the average twice that in summer or because humidity during unusual winter periods was higher than in summer.

Aged↗
PubMed1993

Health care expenditure and income in Europe.

In this work we have tried to analyse the variations in health care expenditure in all the countries of the European Community except Greece and Portugal. We have wanted to provide additional evidence on the empirical relationship between expenditure on health care and income. Our analysis, starting from the approach of Fuchs and Baumol, has been an extension of the traditional studies on health care international comparisons, in at least three directions: we have not imposed any restrictions on the price effects, we have analysed dynamic models instead of the cross-sectional analysis and we have used proper deflators. We have deflated health care expenditure in each country by means of its sectoral price index and by the purchasing parity power of its currency, to allow international comparisons. In the former case we express health care in terms of 'expenditure', in the latter we express health care in terms of 'weighted quantity'. Income elasticities, in the short and in the long-run, have been estimated using econometric methods that allow us to obtain simultaneously equilibrium long-run relationships, if any, and adjustment processes in the short-run. We have found cointegrating relationships and we have estimated consistent estimators of the elasticities. The estimated income elasticities are greater than one in all the models analysed.

Bias↗
PubMed1991

Effects of urban air pollution on emergency room admissions for chronic obstructive pulmonary disease.

The authors assessed the relation between sulfur dioxide and other air pollutants (black smoke, carbon monoxide, nitrogen dioxide, and ozone) and daily emergency room admissions for chronic obstructive pulmonary disease in Barcelona, Spain, during 1985-1986. Barcelona is a Mediterranean city of 1.7 million inhabitants that has air pollution levels lower than standard values. A weak but statistically significant association between emergency room admissions and levels of sulfur dioxide, black smoke, and carbon monoxide was observed. Daily emergency room admissions for chronic obstructive pulmonary disease increased by 0.02 and 0.01 for each microgram of sulfur dioxide and black smoke per cubic meter, respectively, and 0.11 for each milligram of carbon monoxide per cubic meter, after adjusting for meteorologic and temporal variables. Similar estimations were obtained after controlling for the autocorrelation effect by means of time series analysis. In addition, when the data were stratified by season, the effects remained in summer. This strengthened the conclusion that the relation observed in winter, spring, and throughout the study period was indeed real. After truncating the data according to sulfur dioxide or black smoke levels, the authors still found effects for these pollutants at levels below the air quality guideline of 100 micrograms/m3 established by the World Health Organization. The consistency of these results with other recent toxicologic and epidemiologic observations suggest that current air pollution standards do not totally protect public health with a margin of safety in specific places.

Air Pollutants↗
PubMed1991

Repeat pregnancy associated with cardiac pacemaker.

Two pregnancies in a patient with a fixed-rate pacemaker are reported. The first pregnancy was uneventful. The second had no maternal complications either. A moderate tachysystolia was detected during the second period. The newborn was delivered with forceps applied under spinal anesthesia. Newborn infant evolution presented no hazards, but umbilical cord analysis revealed a severe acidosis, in spite of a normal scalp analysis 45 min earlier. Epidural anesthesia is recommended for such patients.

Acidosis↗
PubMedDate not supplied

Shared 'features' in prices: income and price elasticities for health care expenditures.

The evidence found in most studies suggests a strong positive relationship between health care expenditure and gross domestic product. However, this evidence weakens with respect to the actual value of the income elasticity. There are two possible sources of these discrepancies, the use of arbitrary deflators and specification errors. We find that health PPP cannot be taken as a 'universal' price index. The problem is that its components do not move together. Nevertheless, we derive a 'universal' health price index from a dynamic system in which its components share both short and long run co-movements. The omission of relevant explanatory variables seems to be the main cause of the discrepancies. We confirm that there exists a strong positive relationship between per capita health care expenditure and per capita GDP. However we estimate a long run income elasticity at or around unity, although it is greater than unity for the countries with lower per capita income (Spain and Ireland). The results for income elasticity are the same regardless of whether health care expenditure is converted using the GDP PPP or the 'universal' health price index. The importance of non-income variables is also confirmed, in particular the relative price of health care. We find that relative price has a strong rationing effect on the quantity of health demanded and has no effect on the expenditures.

Data Interpretation, Statistical↗
PubMedDate not supplied

[Estimate of daily cases of influenza from the cases notified to the Reportable Disease System: usefulness in time series studies].

In time series analyses assessing the relationship between risk factors and respiratory diseases or mortality, influenza incidence is a potential cofounder and, therefore, must be controlled. Available influenza data come from weekly compulsory notifiable disease (EDO system). Furthermore, its graphical distribution, suggests that information may be underestimated in holiday periods. We have applied a procedure for estimate daily influenza series from the weekly cases, using less, a non-parametric local fit. Findings show that smoothing could avoid stepping and sudden peaks in the original series.

Humans↗
PubMedDate not supplied

[Time series methods in epidemiological studies on air pollution].

The time series methods in the epidemiological studies on air pollution are reviewed, illustrated by means of an autoregressive Poisson regression which was employed in the APHEA and EMECAM Projects. A listing is provided of the variations in the daily number of deaths of people over age 70 (all causes, CIE-9:001-799) in Barcelona, 1991-1995, with the average variations in the daily smog pollution levels. A Poisson regression is used insofar as the dependent random variable presumably follows such a probability distribution. As variable possibly leading to confusion, the impact of weather variables (daily temperature and relative humidity averages), seasonal, tendency-related behaviours and day of the year on the death rate are taken into account (all estimated on a determinist basis), in addition to any other variable which behaves in a way that it can be related to the dependent variable (i.e. flu epidemics). The relationship between the death rate and the confusing-causing variables is modelled on a non-linear basis, and the foreseeable lag times are also taken into account (i.e. by using explicative variable time lags). However, due to control not being perfect, it has been decided to opt for estimating an autoregressive Poisson model (adding in some different explicative variables time giving rise to a lag in the death rate) offsetting the residual autocorrelation. The main advantage of the method of analysis described above is that of making it possible to control confusing variables from a determinist standpoint with a software to which all of the groups taking part in this Project had access. This also affords the possibility of using this method in a set, standardized manner, facilitating the comparison of results and making an objective point analysis possible.

Age Factors↗