Biomedical subjects

Adolfo Figueiras

Publications and source records attributed to Adolfo Figueiras.

22 records · Page 2Linked to original sources

PubMed2002

Intake of vitamin C and zinc and risk of common cold: a cohort study.

To examine whether intake of vitamin C and zinc is associated with a decrease in the risk of a common cold, we analyzed data from a cohort study carried out in a population of 4,272 faculty and staff from five Spanish universities. Participants were 21-65 years of age, were full-time workers at those universities, and did not have antecedents of asthma or chronic obstructive pulmonary disease. Daily intake of vitamin C and zinc was assessed at baseline by means of a food frequency questionnaire of which the validity and reproducibility were determined in a sample of the population. Subjects were traced for 1 year to detect episodes of common cold, the diagnosis of which was based on symptoms and was validated by additional clinical signs. We detected 1,667 cases of common cold in 79,240 person-weeks of follow-up. Intake of vitamin C and zinc was not related to the occurrence of common cold. Compared with the first quartile of intake, women in the fourth quartile of vitamin C intake showed an adjusted incidence rate ratio of 1.0 (95% CI = 0.7-1.3), and for zinc intake this figure was 1.1 (95% CI = 0.8-1.5). The incidence rate ratios for men in the fourth quartile were 1.1 (95% CI = 0.8-1.4) for vitamin C and 1.3 (95% CI = 0.9-1.8) for zinc.

Adult↗

PubMed2002

A population-based case-control study on fruit and vegetable intake and lung cancer: a paradox effect?

A population-based case-control study was carried out in Northwest Spain to analyze the effect of fruit and vegetable intake on the appearance of lung cancer. A non-significant protective association was found for overall consumption of leafy green and other vegetables, with consumption once a day or more vs. less than once a week yielding odds ratios of 0.63 [95% confidence interval (CI) = 0.24-1.63] for leafy green vegetables and 0.64 (95% CI = 0.30-1.36) for other vegetables. A significant protective association was found for potato consumption. No protective associations were recorded for fruit, whether overall or singly; instead, fruit consumption once a day or more vs. less than once a week registered a risk of 2.16 (95% CI = 1.02-4.58). Although the possibility that this effect may be due to a phenomenon of reverse causation cannot be ruled out, these results could support other reports and hypotheses which indicate that the protective effect of fruit might not be as pronounced as generally thought.

Aged↗

PubMed2002

A combined analysis of the short-term effects of photochemical air pollutants on mortality within the EMECAM project.

In recent years, some epidemiologic studies have attributed adverse effects of air pollutants on health not only to particles and sulfur dioxide but also to photochemical air pollutants (nitrogen dioxide and ozone). The effects are usually small, leading to some inconsistencies in the results of the studies. Furthermore, the different methodologic approaches of the studies used has made it difficult to derive generic conclusions. We provide here a quantitative summary of the short-term effects of photochemical air pollutants on mortality in seven Spanish cities involved in the EMECAM project, using generalized additive models from analyses of single and multiple pollutants. Nitrogen dioxide and ozone data were provided by seven EMECAM cities (Barcelona, Gijón, Huelva, Madrid, Oviedo, Seville, and Valencia). Mortality indicators included daily total mortality from all causes excluding external causes, daily cardiovascular mortality, and daily respiratory mortality. Individual estimates, obtained from city-specific generalized additive Poisson autoregressive models, were combined by means of fixed effects models and, if significant heterogeneity among local estimates was found, also by random effects models. Significant positive associations were found between daily mortality (all causes and cardiovascular) and NO(2), once the rest of air pollutants were taken into account. A 10 microg/m(3) increase in the 24-hr average 1-day NO(2)level was associated with an increase in the daily number of deaths of 0.43% [95% confidence interval (CI), -0.003-0.86%] for all causes excluding external. In the case of significant relationships, relative risks for cause-specific mortality were nearly twice as much as that for total mortality for all the photochemical pollutants. Ozone was independently related only to cardiovascular daily mortality. No independent statistically significant relationship between photochemical air pollutants and respiratory mortality was found. The results in this study suggest that, given the present levels of photochemical pollutants, people living in Spanish cities are exposed to health risks derived from air pollution.

Adolescent↗

PubMedDate not supplied

[Statistical processing of non-response in transversal epidemiological studies].

In epidemiological surveys, non-response constitutes a great limitation due to the loss of validity and statistical power it represents, whether such a loss occurs due to partial participation (the individual fails to answer certain variables) or due to total lack of participation (the individual does not answer any variable). This paper reviews the scientific literature on the different methods to process statistic data when non-response has occurred in non-longitudinal studies, so as to counteract their effect in such studies. Most statistical methods focus on dealing with partial participation (missing data). These methods, of which there is a great variety, can be classified into two large groups: imputation and complete data. For accurate selection of the study method, it is necessary to study the data matrix beforehand, observing the missing data generation mechanism, as well as the proportion they represent of the total data.

Cross-Sectional Studies↗