Blood pressure in Spain: distribution, awareness, control, and benefits of a reduction in average pressure.

Distribution of blood pressure (as per US Joint National Committee VI classification and staging criteria) plus awareness, treatment, and control of hypertension were studied in a representative Spanish population sample of 2021 persons (age range, 35 to 64 years). Pressure was determined in accordance with World Health Organization guidelines. A total of 45.1% of subjects were hypertensive (>/=140/>/=90 mm Hg or undergoing drug therapy); 12% had isolated systolic hypertension, and 8.7% had isolated diastolic hypertension. Pulse pressure was 48.7 mm Hg. Heart rate was 81.4 bpm in untreated hypertensives and 78.9 bpm in normotensives (P<0.05). A substantial proportion of the community burden of blood pressure was attributable to stage 1 (28.3% of subjects), the most frequent category of hypertension, and to the high-normal blood pressure group (17% of subjects). A percentage breakdown showed that among hypertensives, 44.5% were aware of their condition; of these, 71.9% were undergoing drug therapy, and of those being treated, only 15.5% were controlled (5% of hypertensives). Not only are these figures consistent with the fact that Spain has a higher cerebrovascular mortality than other countries such as the United States, but they represent a great potential for improvement, particularly among those groups registering relatively worse data (younger men, rural residents, and unskilled professionals). A decrease of only 1 to 4 mm Hg in average blood pressure could reduce the prevalence of hypertension in Spain by 12.4% to 15.4%.

Adult men born in spring have lower blood pressure.

OBJECTIVE: To determine whether there is a relationship between season of birth and adult blood pressure, as a possible early determinant of later blood pressure. DESIGN: We studied 572 men, aged 45-64 years, whose blood pressure was measured in standardized manner as part of a nation-wide survey in Spain. To analyse the seasonal variation in blood pressure, a linear regression was performed, adjusting for age, height, body mass index, occupation and rural or urban residence. RESULTS: We found seasonal variation in mean systolic blood pressure, with maxima in adults born in autumn and winter, and minima in those born in spring and summer. The greatest difference in systolic blood pressure occurred between adults born in spring (134.1 mmHg) and those born in autumn (140.3 mmHg). After adjustment, the difference in means between spring and autumn was 5.9 mmHg (95% confidence interval 0.7 to 11.1 mmHg, P = 0.03). CONCLUSIONS: This study demonstrated differences in systolic blood pressures of adult men according to the season of their birth. Although this relationship is compatible with several hypotheses, the difference found between spring and autumn, partially independent of some other factors, might indicate that the extent of early exposure to sunlight is implicated in determining later blood pressure. This needs further investigation.

Lower consumption of wine and fish as a possible explanation for higher ischaemic heart disease mortality in Spain's Mediterranean region.

BACKGROUND: There is an apparent paradox in the geographical distribution of ischaemic heart disease (IHD) mortality in Spain. The Mediterranean regions, those with the lowest consumption of total and saturated fats, register the highest mortality due to IHD. This paper seeks to explain this paradox by examining the provincial distribution of IHD mortality in Spain and their known risk factors, dietetic and non-dietetic. METHODS: The study was based on data aggregated by province. Mortality data were taken from official vital statistics, while data on diet and other lifestyle habits were obtained from representative, large-scale, sample-based population surveys. Correlation and multiple regression analyses were run on standardized IHD mortality ratios for the period 1983-1987 and potential dietetic and non-dietetic determinants in 1989-1981. RESULTS: Intake of total lipids, saturated and polyunsaturated fatty acids, fish and wine were lower in Spain's southern and eastern provinces. Consumption of wine, fish, chicken, dairy products, vegetables and blond cigarettes, as well as unemployment, explained 53% of the variation in IHD mortality. Consumption of fish and wine alone exhibited a statistically significant relationship (P < 0.05) with IHD mortality. Moderate consumption of wine was negatively associated with IHD mortality, whereas heavy consumption patterns revealed a positive association. CONCLUSIONS: Based on correlation analyses of ecological data, lower consumption of wine and fish may explain the apparent paradox of higher IHD mortality in the presence of a lower intake of saturated fats in Spain's Mediterranean regions.

The growth of micro-organisms in intravenous fluids.

The growth of four micro-organisms in 12 different intravenous fluids at room temperature was studied. Gram-negative organisms grew better than Gram-positive, and lipid solutions were most favourable to microbial growth. Microbial growth was inhibited in solutions with osmolalities over 500 mosmol/l; Staphylococcus epidermidis was inhibited by inocula with Gram-negative bacilli, while the growth of Gram-negative bacilli generally was not affected. Candida albicans was inhibited by Gram-negative bacilli in lipid and 5% dextrose solutions.

Association between the occurrence of antibodies to simian vacuolating virus 40 and bladder cancer in male smokers.

An association between the occurrence of antibodies to simian vacuolating virus 40 and bladder cancer in male smokers was found in a case-control study conducted in 200 male patients with bladder cancer and 400 control men. The risk of bladder cancer increases with the years of cigarette smoking.

Risk factors of bladder cancer in Spain.

A case-control study was performed on 406 (353 males and 53 females) bladder cancer patients and 406 controls matched in age, sex and date of admission to the hospital. The questionnaire included questions about socio-economic status, residence, personal and familial histories of diseases, professional occupations, and habits such as cigarette smoking and consumption of coffee, artificial sweeteners, alcoholic and nonalcoholic beverages, and water. Up to three different exposures to occupational risks were taken into account. Data were studied by a discriminant analysis technique. The results suggest a multifactorial etiology for this disease. The factors increasing the risk of bladder cancer, listed in order of importance, were: total number of cigarettes smoked, history of urologic disease, second exposure to an occupational risk, use of artificially sweetened beverages, low consumption of water, family history of cancer, third occupational exposure to a risk, use of artificial sweeteners, and years of coffee drinking.

[Geographic variation in hospitalizations and mortality related to congestive heart failure in Spain, 1980-1993]. / Variación geográfica en las hospitalizaciones y en la mortalidad por insuficiencia cardíaca congestiva en España, 1980-1993.

BACKGROUND AND OBJECTIVES: Geographical differences in hospitalizations and mortality for heart failure serve to estimate the potential for reducing the associated hospital and demographic burden on the population. Accordingly, the objective of this paper is to analyze the geographic variation in heart failure hospitalizations and mortality in Spain during the period of 1980-1993, and to examine their potential determinants. METHODS: Data on the primary diagnosis of heart failure were taken from the National Hospital Morbidity Survey and National Vital Statistics. Information on determinants of heart failure were obtained from large-scale nationally representative surveys conducted by the National Statistics Office. RESULTS: The period of 1980-1993 witnessed a decrease in geographical differences in heart failure hospitalizations and mortality. Theoretically, however, heart failure hospitalizations and mortality among persons aged > or = 45 years could still be further reduced by 60% and 30% respectively. In the period of 1989-1993 heart failure hospitalizations were correlated (p < 0.05) with ischaemic heart disease hospitalizations and the number of beds/1,000 inhabitants. Heart failure mortality showed a statistically significant correlation (p < 0.05) with ischaemic heart disease mortality, illiteracy and unemployed status. CONCLUSIONS: There is a great potential for a reduction in the hospital and demographic burden of heart failure in Spain. Control of ischaemic heart disease and a reduction in the geographical differences in socio-economic status would probably contribute to lessening the healthcare burden of heart failure in Spain.

Bladder cancer and asbestos in Spain.

The relationship between bladder cancer and occupational exposure to asbestos was investigated between 1978 and 1982 at La Paz Hospital in Madrid in a case-control study conducted among 353 male patients and 53 women with a diagnosis of urothelium carcinoma, and among an equal number of controls matched in age (decade of life), sex and date of admission to the hospital. The results showed that bladder cancer is associated with occupational exposure to asbestos.

How much benefit could be obtained from cardiovascular disease intervention programs?

To estimate the potential benefits of cardiovascular disease intervention programs in Spain, we have computed cardiovascular population mortality fractions and deaths attributable to the main risk factors by using relative risks from international studies and Spanish prevalence and mortality data (subjects of both sexes, aged 25-64). As many as 71% of the cardiovascular deaths studied in men and 44% in women might be delayed every year in Spain if it were possible to eliminate the current exposure of the population to smoking, obesity, sedentariness, hypertension and hypercholesterolemia. With the eradication of tobacco exposure 31% of coronary deaths and 16% of stroke deaths in men (7% in both cases for women) might be avoided. Similar actions on sedentariness, hypertension and hypercholesterolemia might delay 17% and 29%, 13% and 13%, and 9% and 11% of deaths, respectively, in males (figures generally somewhat higher in females). These figures would be moderately lower if reductions in the prevalence of these factors are considered realistically. These results may encourage the implementation of strategies against cardiovascular diseases in countries with risk factor prevalence similar to that of Spain.

[Eat less fat to prevent ischemic cardiopathy. The potential impact of population and individual strategies for controlling cholesterolemia in Spain]. / Comer menos grasa para prevenir la cardiopatía isquémica. Impacto potencial de las estrategias poblacional e individual de control de la colesterolemia en España.

BACKGROUND: The aim of the application of population and individual strategies for the control of cholesterolemia recommended by several commissions of experts in Spain is to obtain marked decreases in mortality by ischemic heart disease. This study is the first to estimate the potential benefits obtained by the application of both strategies in males from 35 to 64 years of age in Spain. METHODS: Upon fixing the population dietetic aims for the ingestion of fats and cholesterol, the foreseen decrease in mean serum cholesterol was estimated by predictive equations. For individuals at risk, more ambitious objectives were made in regard to decrease in cholesterolemia. The consequent reduction of coronary death risk was obtained for each strategy comparing the foreseen coronary risks by logistic functions for previous serum cholesterol values and those posterior to the health intervention. RESULTS: The population decrease of saturated fat to 7-10% of total calories of the diet and of the consumption of cholesterol to 300 mg/day would produce a reduction of serum cholesterol of between 6.5 and 21.4 mg/dl (0.2-0.6 mmol/l) which would represent nearly 200 mg/dl (5.2 mmol/l). This would then produce a decrease in coronary deaths of 5.5 to 17.1%. This population strategy must reach 934 to 2,857 people per death avoided. With the individual strategy, the reduction of 55 mg/dl (1.4 mmol/l) in mean cholesterolemia of subjects with more than 250 mg/dl (mean 7.1 mmol/l) or of 36 mg/dl (0.9 mmol/l) in those with more than 200 mg/dl (mean 6.2 mmol/l) would produce a decrease of population coronary death between 3.3 and 12.5% in the first group, and 5.2 to 20% in the second requiring 237 or 454 subjects in each group, respectively per death avoided. The joint application of both strategies would reduce the risk from 8.4 to 24.5%. This would delay the appearance of 570 to 1,640 coronary deaths each year. CONCLUSIONS: The population strategy for cholesterolemia control provides greater health benefits, within a short term, than those of individual strategy although it must be applied to more subjects per unit of benefit. The joint application of both strategies may produce a modest but appreciable reduction, within a medium term, of coronary death in Spain.

[Cardiovascular mortality in Spain and its autonomous communities (1975-1992)]. / Mortalidad cardiovascular en España y sus comunidades autónomas (1975-1992).

BACKGROUND: Given the great relevancy of the cardiovascular diseases, were analyzed the cardiovascular mortality in the Spanish autonomous communities and its trend during the period 1975-1992, to identify communities with a high death risk by these diseases and to as certain the underlying factors. MATERIAL AND METHODS: The mortality rates standardized by age are calculated for the diseases of the circulatory system (DCS), ischaemic heart disease (IHD) and cerebrovascular disease (CVD). The mortality trend has been quantified through the percentual change annual means, using a log-lineal model. RESULTS: The Communities of Valencia, Extremadura, Andalusia and Murcia show the highest cardiovascular diseases mortality rates while the Communities of Madrid, Navarra, Castilla and Leon and Aragon present the most decreases. In all the communities a decrease of the mortality by DCS has occurred, that ranges from a percentual decrease annual means higher than 3% in Navarre (-3.7%) and Madrid (-3.4%) to values that they do not reach to the 2% of decrease in Murcia (-1.8%) and Balearic Islands (-1.9%). In males as well as in females, the mortality by IHD and CVD falls in all the communities in the period 1975-1992, though the decrease is much greater for CVD. CONCLUSIONS: This study demonstrates a consistent fall of the cardiovascular mortality in all the Spanish autonomous communities and some considerable differences in the level and in the trends of the magnitude mortality among these communities during all the studied period.

[Estimation of surgical wound infection rates using a post-hospital surveillance program]. / Estimación de las tasas de infección de herida quirúrgica mediante un programa de vigilancia tras el alta hospitalaria.

BACKGROUND: The decrease in the time spent in hospital of patients who have undergone surgery lessens wound observation time, and thus could underestimate the true rates of surgical wound infection (SWI). The aim of this study was to assess the use of a programme to detect SWI, by carrying out a control 30 days after patients have been discharged from hospital. PATIENTS AND METHODS: A study of a prospective cohort of 2,015 patients who were operated in 6 surgical services at a general hospital, was carried out to detect the incidence of SWI. The control at one month after discharge from hospital was done through a telephone survey using a specific questionnaire. RESULTS: SWI incidence was observed in 134 patients (6.7%), 38% of which were detected on the month after discharge from hospital. In the postoperatory control the major SWI rates were detected in the clean procedures and in the clean-contaminated procedures with 46% and 37%, respectively. The telephone interview enabled contact with 72.3% of the patients intervened. CONCLUSIONS: The post-discharge control of patients who have undergone surgery enabled the detection of more than a third of SWI cases. The telephone interview system has been effective in our study as a postdischarge method of the localization of patients.

[Hypertension-related mortality and arterial pressure in Spain]. / Mortalidad relacionada con la hipertensión y la presión arterial en España.

BACKGROUND: Given the high figures of cardiovascular disease and hypertension in Spain, and the continuity of cardiovascular and total mortality risks at any level of blood pressure, mortality related to hypertension and blood pressure is estimated. SUBJECTS AND METHODS: Blood pressure distribution from a representative sample of the 35 to 64 years old Spanish population and the relative risks for death coming from valid and reasonably generalizable international studies (MRFIT, Framingham and Chicago Project) were used. The proportions and absolute numbers of cardiovascular and total deaths related to blood pressure and hypertension (categories of the US Joint National Committee VI [JNC VI]) have been calculated in middle-aged men and women. RESULTS: As many as 42% of the coronary deaths, 46.4% of the stroke deaths and 25.5% of the total deaths are related to hypertension (> or = 140/90 mmHg), most of them in stages 1 and 2. It follows high-normal plus normal blood pressure group (8.3, 10.2 and 6.2% of these deaths, respectively). All together, 17,266 total deaths and 4,502 cardiovascular deaths related to blood pressure took place annually, three-quarters of them in males. Over the last ones, 65.5% are coronary and 34.5% cerebrovascular, prevailing the first ones in both sexes. Eight out of 10 deaths, cardiovascular or total, related to blood pressure are concentrated in the hypertension categories, and two out of 10 in the high-normal or normal blood pressure groups. CONCLUSIONS: One out of 3 total deaths and one out of 2 cardiovascular deaths are related to blood pressure. One out of 4 total deaths and one out of 2.5 cardiovascular deaths are related to hypertension. A substantial part of these deaths come from stages 1 and 2 hypertension and from high-normal and normal blood pressure group.

[Wine consumption and ischemic heart disease mortality in Spain]. / El consumo de vino y la mortalidad por cardiopatía isquémica en España.

BACKGROUND: To identify the determinants of the geographic distribution of ischaemic heart disease (IHD) mortality in Spain. POPULATION AND METHODS: Ecological study at the provincial level. Data are obtained from the 1976-1980 vital statistics, the 1964-1965 Household Budget Survey and the 1970 Population Census. RESULTS: Consumption of wine, chicken, fish, and vegetables, as well as illiteracy, explain 47% of IHD mortality. Consumption of wine alone exhibits a statistically significant relationship (p < 0.05) with IHD mortality. Moderate consumption of wine is negatively associated with IHD mortality, whereas higher consumption reveals a positive association. CONCLUSION: Results are consistent with those from an earlier study in Spain for the 1983-1987 period.

[The decline in moderate alcohol consumption has been associated with a decrease in heavy drinkers in Spain in the 1987-1993 period]. / La disminución del consumo moderado de alcohol se ha asociado a un descenso de los bebedores excesivos en España en el período 1987-1993.

BACKGROUND: To examine whether the decline in alcohol consumption among moderate drinkers, which has occurred in Spain in the period 1987-1993, has been associated with changes in the proportion of heavy drinkers and abstainers. SUBJECTS AND METHODS: The units of analysis have been the 17 administrative regions of Spain. Alcohol consumption data have been taken from the 1987 and 1993 National Health Interview Surveys. RESULTS: A decrease of 10 g/week in mean alcohol consumption among male moderate drinkers has been associated with a decrease of 1.2% (95% CI: 0.7-1.7%) in the proportion of heavy drinkers. The association was also observed among women, those over and below 45 years of age, and was stronger for wine than for other alcoholic beverages. CONCLUSION: The decrease in moderate consumption of alcohol has probably had a beneficial effect on the health of the Spanish population.

[Environmental factors during early life and socioeconomic status in the present: which is more important for cardiovascular mortality in Spain?]. / Factores ambientales en la vida temprana y nivel socioeconómico en la actualidad: cuál es más importante para la mortalidad cardiovascular en España?

BACKGROUND: To examine whether provincial mortality from ischaemic heart disease and cerebrovascular disease in Spain in 1991-1995 is associated with infant mortality in 1930-1934, independently of illiteracy (an estimator of socioeconomic status) in 1991. MATERIAL AND METHODS: Population-correlation study. RESULTS: Infant mortality is correlated with mortality from ischaemic heart disease (r = 0.38; p < 0.01) and cerebrovascular disease (r = 0.41; p < 0.01). When adjusting for illiteracy rate in 1991, the correlation of infant mortality with ischaemic heart disease mortality is r = 0.01 (p = 0.93), and with cerebrovascular disease mortality is r = 0.25 (p = 0.08). CONCLUSIONS: Ischaemic heart disease and cerebrovascular disease mortality are moderately associated with infant mortality during the 1930s. This association might be explained by present socioeconomic status.

[Smoking and subjective health in Spain]. / Consumo de tabaco y salud subjetiva en España.

BACKGROUND: To examine the relationship between smoking and subjective health in Spain. MATERIAL AND METHOD: Datacome from the 1993 National Health Survey. Analyses were performed with logistic regression, adjusting for the main confounding factors. RESULTS: Among those less than 25 years, there is a dose-response relationship (p = 0.0001)between cigarette consumption and suboptimal health (fair, pooror very poor health). CONCLUSIONS: Smoking controlactivities should inform on the worse subjective health of youngsmokers, for whom other effects of tobacco smoking are less relevant because they appear to happen in the distant future.

[The contribution of tobacco and other life-style habits to mortality from lung cancer in Spain from 1940 to 1988]. / La contribución del tabaco y de otros hábitos de vida a la mortalidad por cáncer de pulmón en España de 1940 a 1988.

Because the causal relationship between tobacco smoking and lung cancer has been clearly established, we have set out to measure its magnitude among the Spanish population in the time period 1940-1988 using observational methods. To do so, we have carried a time series study of ecological data. Information on lung cancer mortality, tobacco smoking and other potential predictors of lung cancer has been elaborated from official statistics. Data analysis has been performed by graphical methods and multiple linear regression techniques. Lung cancer mortality, tobacco smoking, total lipid intake and the Spanish wealth, as measured by national per caput income and gross domestic product, have increased very importantly over the study period. After controlling for the effect of lipids and alcohol intake, for every gram/per caput/day of increase in tobacco smoking in the period 1940-1988, there has been a 19% increase in lung cancer mortality with a 15 year lag. We conclude that tobacco smoking has fueled the lung cancer epidemic in Spain during the study period. This finding provides additional arguments for the implementation of tobacco control programmes in our country.

[Age-period-cohort analysis of mortality caused by ischemic cardiopathy in Spain 1965-1985]. / Análisis edad-período-cohorte de la mortalidad por cardiopatía isquémica en España 1965-1985.

With the objective of studying the temporal evolution of ischaemic cardiopathy (IC), or coronary heart disease mortality, in Spain, we carried out a cohort analysis with conventional graphic techniques and modern statistical methods. This permits better understanding and quantification of the age-period-cohort effects and identification of the potential factors operating upon them. To this end, loglineal (Poisson regression) models were constructed of the IC mortality rates for both sexes, using the GLIM package, in which the regression coefficients are the natural Relative Risk (RR) logarithms of the various age groups (35-74 years), period of death (1970-1985) and birth cohort (1985-1960) with respect to the reference group mortality, controlled by the effect of other groups. In respect of the results, the maximum RR value corresponds to decrease year 1975, and falls progressively to 1985, though at all times remaining above the 1970 value. The effect of 1985, though less than 1980, does not present significant differences from the latter. Nevertheless, no clear cohort effect was found. As a probable explanation for the pattern observed, this would suggest recent changes in life style and in medical attention. There is a discussion of the consistency of the models selected with the graphical results and with present knowledge of the natural history of IC and with the evolution of its determining factors, together with validation of the models. In summary, the IC mortality patterns observed show an increase up to the mid-seventies, and stabilization from that date onwards, in all age and sex groups, which is consistent with an age-period effect.

[Popper and the problem of induction in epidemiology]. / Popper y el problema de la inducción en epidemiología.

In this article we are discussing a few of the contributions by the Austro-British philosopher Karl R. Popper, one of our most influential contemporary thinkers, whose epistemological and socio-political theories have also penetrated the sphere of epidemiology. We are focusing mainly on the so-called problem of induction. We sustain, in line with Popper, that the scientific method does not use inductive reasoning, but rather hypothetical-deductive reasoning. Although the movement from the data evaluating a hypothesis to a conclusion on the latter goes from the specific to the general, that is, in an inductive direction, the induction does not exist as a reasoning process or inference. That is, there is no method that enables us to infer or to verify hypotheses or theories (we cannot explore all of the possible situations to see whether the theory stands up), or even to render them very probable. Besides, scientists look for highly informative theories, not highly probable ones. What we actually do is to propose a hypothesis as a tentative solution to a problem, to confront the prediction deduced from the hypothesis with actual experience, and evaluate whether the hypothesis is rejected or not by the facts. As theories cannot be verified, we can only accept them if they withstand an attempt to reject them. Consequently, the test of a theory consists of criticism or a serious attempt at falsification, that is, the elimination of error within a theory, in order to reject it if it is false. The objective is, thus, the search for true theories. For this purpose, the scientific method uses a systematic set of methodological (not logical) rules, that is, decisions. These methodological rules or principles can be summed up in two: [symbol: see text]be inventive and critical!, that is, propose bold hypotheses and subject them to severe tests of experience. Logic plays its role mainly by allowing us to deduce from a hypothesis the predictions to be confronted with the facts or evidence. This is applicable both to statistical inference as well as to causal inference. We argue that the criteria of causality used in epidemiology are none other than rules of the method designed for the same purpose: they are concerned with eliminating or reducing errors (chance, bias...) on testing a causal hypothesis. Consequently, the so-called ausal inference, the step from evidence to causal theory, is not a logical inductive or probabilistic process but rather a decision based on the evaluation of a causal hypothesis thanks to methodological rules such as the criteria of causality. We believe that the interest of the debate between the Popperian and the inductivist epidemiologists is not merely a matter of words, as, if we are aware that we do not operate inductively, that we cannot establish firmly hypotheses, not even affirm them probabilistically, we will presumably adopt a humbler attitude and look more for the errors in our theories than for their facile examples of confirmation.