Showing papers in "International Journal of Epidemiology in 1989"

Food-Based Validation of a Dietary Questionnaire: The Effects of Week-to-Week Variation in Food Consumption

Abstract: The reproducibility and validity of responses for 55 specific foods and beverages on a self-administered food frequency questionnaire were evaluated. One hundred and seventy three women from the Nurses' Health Study completed the questionnaire twice approximately 12 months apart and also recorded their food consumption for seven consecutive days, four times during the one-year interval. For the 55 foods, the mean of correlation coefficients between frequencies of intake for first versus second questionnaire was 0.57 (range = 0.24 for fruit punch to 0.93 for beer). The mean of correlation coefficients between the dietary records and first questionnaire was 0.44 (range = 0.09 for yellow squash to 0.83 for beer and tea) and between the dietary records and the second questionnaire was 0.52 (range = 0.08 for spinach to 0.90 for tea). Ratios of within- to between-person variance for the 55 foods were computed using the mean four one-week dietary records for each person as replicate measurements. For most foods this ratio was greater than 1.0 (geometric mean of ratios = 1.88), ranging from 0.25 (skimmed milk) to 14.76 (spinach). Correlation coefficients comparing questionnaire and dietary record for the 55 foods were corrected for the within-person variation (mean corrected value = 0.55 for dietary record versus first questionnaire and 0.66 versus the second). Mean daily amounts of each food calculated by the questionnaire and by the dietary record were also compared; the observed differences suggested that responses to the questionnaire tended to over-represent socially desirable foods. This analysis documents the validity and reproducibility of the questionnaire for measuring specific foods and beverages, as well as the large within-person variation for food intake measured by dietary records. Differences in the degree of validity for specific foods revealed in this type of analysis can be useful in improving questionnaire design and in interpreting findings from epidemiological studies that use the instrument.

The Prevalence of Hearing Impairment and Reported Hearing Disability among Adults in Great Britain

Abstract: Estimates for the prevalence of self-reported hearing disability and measured hearing impairment as a function of age in the adult population of Great Britain (GB) are reported from two 2-stage surveys. The main study was conducted in Cardiff, Glasgow, Nottingham and Southampton, with rigorous audiological assessment at the second stage. A supplementary study used a sample representative of GB with simplified domiciliary audiological assessments. In the main study, neither stage showed any gross bias arising from the particular cities chosen; the estimates from the first stage are free of bias arising from non-response. The estimates from the second stage are relatively free of bias arising from non-attendance. For the present purposes, defining a 'significant' level of hearing impairment as at least 25 dBHL averaged over the frequencies 0.5, 1, 2, 4 kHz, 16% of the adult population (17-80 years) have a bilateral, and about one in four a unilateral or bilateral, hearing impairment. About 10% of the adult population (aged 17+) report bilateral hearing difficulty in a quiet environment.

Ecological Bias, Confounding, and Effect Modification

Abstract: Ecological bias is sometimes attributed to confounding by the group variable (ie the variable used to define the ecological groups), or to risk factors associated with the group variable. We show that the group variable need not be a confounder (in the strict epidemiological sense) for ecological bias to occur: effect modification can lead to profound ecological bias, whether or not the group variable or the effect modifier are independent risk factors. Furthermore, an extraneous risk factor need not be associated with the study variable at the individual level in order to produce ecological bias. Thus the conditions for the production of ecological bias by a covariate are much broader than the conditions for the production of individual-level confounding by a covariate. We also show that standardization or ecological control of variables responsible for ecological bias are generally insufficient to remove such bias.

WHO MONICA Project: risk factors.

Abstract: The WHO MONICA Project was designed to measure trends and determinants in cardiovascular disease mortality and coronary heart disease and cerebrovascular disease morbidity, and to assess the extent to which these trends are related to changes in known risk factors in 39 collaborative centres in 26 countries. Results of the baseline population surveys are presented. Use of standardized methods allows cross-sectional comparisons to be made of data from the 39 collaborating centres. The proportion of smokers varied between 34-62% among men and 3-52% among women. The median systolic blood pressure (SBP) values varied from 121 mmHg to 145 mmHg in men and from 117 mmHg to 143 mmHg in women. Median diastolic blood pressure (DBP) values varied from 74 mmHg to 91 mmHg in men and from 72 mmHg to 89 mmHg in women. The prevalence of actual hypertension, defined as SBP and/or DBP greater than 159/94 mmHg, or on antihypertensive medication, varied between 8.4% and 45.3% in men and between 12.6% and 40.5% in women. Median serum total cholesterol values varied from 4.1 mmol/l to 6.4 mmol/l in men and from 4.2 mmol/l to 6.4 mmol/l in women. The results show that there is a large variability in the risk-factor patterns among the MONICA populations. They also indicate that populations with low levels of risk factors are in the minority.

Parental Height: Childhood Environment and Subsequent Adult Height in a National Birth Cohort

Abstract: Low parental social class was associated with shorter adult stature in offspring in a national birth cohort. Since short adult stature is a risk factor for serious illness, particularly heart disease, origins of the observed class differences were sought in the childhood environment and in combined genetic and environmental factors represented by midparent height and birthweight. In addition to social class the childhood environmental factors of birth order, number of surviving younger siblings, overcrowding and mother's education were found to be significant and independent predictors of adult height, even after adjusting for parental heights and birthweight, and had therefore a long-term intragenerational effect. Both midparent height and birthweight constitute a combination of environmental and genetic influences, and therefore to some extent are an intergenerational effect. Improvements in environmental factors are thus likely to reduce social variation in adult height for both intra and intergenerational reasons.

What Symptoms Predict the Bronchial Response to Histamine? Evaluation in a Community Survey of The Bronchial Symptoms Questionnaire (1984) of The International Union Against Tuberculosis and Lung Disease

Abstract: A questionnaire developed by the International Union against Tuberculosis and Lung Disease (IUATLD) to assess bronchial symptoms has been tested for its ability to predict the bronchial response to histamine in adults aged 18-64 years living in two areas of southern England. A number of questions were found to be independently associated with increased reactivity in the first randomly selected half of the subjects. These symptoms included wheeze, waking at night with shortness of breath, tightness in the chest or shortness of breath when exposed to animals, dust or feathers and the non-specific symptom of persistent problems with breathing. A predictive score based on these symptoms was more sensitive and only slightly less specific than the question on wheeze alone in predicting the response to histamine in the second half of the subjects. Questions about asthma though more specific were considerably less sensitive than either. Symptoms did not differentiate between reactivity associated with positive skin tests and that associated with smoking.

A Meta-Analysis of Acupuncture for Chronic Pain

Abstract: Results of 14 randomized controlled trials of acupuncture for chronic pain were pooled in a meta-analysis and analysed in three subgroups according to site of pain; and in two subgroups each according to type to trial, type of treatment, type of control, 'blindness' of participating agents, trial size, and type of journal in which results were published. While few individual trials had statistically significant results, pooled results of many subgroups attained statistical significance in favour of acupuncture. Various potential sources of bias, including problems with blindness, precluded a conclusive finding although most results apparently favoured acupuncture.

International Mortality from Heart Disease: Rates and Trends

Abstract: Mortality trends are described for heart disease, its main subgroup coronary heart disease (CHD), and total mortality for men and women 45-64 years of age from 1950 to 1985 in 27 countries. In contrast to the epidemic rise in mortality from CHD prior to the 1960s, the death rate is declining in most industrialized countries except in Eastern Europe where trends remain upward. Mortality from CHD was upwards in 18 countries in the 1970s and in only four countries in the 1980s. Peaks for CHD occurred earlier in women than men. With some exceptions, declines were greater for higher than lower rate countries. In many countries, CHD declines are accompanied by a corresponding downward change in total mortality, which suggests that the declines are real. Although in several countries there is substantial mortality from heart diseases other than CHD, generally there is good correspondence in trends between them over the 35-year period. There is also a trend toward less intercountry variability in death rates and proportionate mortality for CHD. But the North-South high-to-low gradient in Europe continues in 1985, and there remains at least a fourfold difference for men and an eightfold difference for women between the highest and lowest CHD rates. The male/female ratios of the rates, while narrowing in many countries, vary from 3:1 to 6:1 among the 27 countries.

Ethnicity and Other Characteristics Predictive of Coronary Heart Disease in a Developing Community: Principal Results of the St James Survey, Trinidad

Abstract: A ten-year community survey was undertaken to investigate the high coronary heart disease (CHD) incidence among people of Indian (South Asian) descent in Trinidad, West Indies. Of 2491 individuals aged 35-69 years, 2215 (89%) were examined and 2069 (83%) found to be clinically free of CHD at baseline. After exclusion of 71 of minority ethnic groups, 786 African, 598 Indian, 147 European and 467 adults of Mixed descent were followed for CHD morbidity and mortality. In both sexes, adults of Indian origin had higher prevalence rates of diabetes mellitus, a low concentration of high-density lipoprotein (HDL) cholesterol, and recent abstinence from alcohol than other ethnic groups. Indian men also had larger skinfold thicknesses than other men. In participants free of CHD at entry, the age-adjusted relative risk of a cardiac event believed due to CHD was at least twice as high in Indian men and women as in other ethnic groups. In men, blood pressure, diabetes mellitus and low-density lipoprotein (LDL) cholesterol concentration were positively and independently related to risk of CHD, whereas alcohol consumption and HDL cholesterol concentration were inversely associated with risk after allowing for age and ethnic group. The ethnic contrasts in CHD persisted when these characteristics were taken into account. In the smaller sample of women, only ethnic group was predictive of CHD as defined. The failure of point estimates of risk to explain the high CHD incidence in Indians calls for focus on age of onset of risk and examination of other potential risk factors such as insulin concentration.

Using the WHO (Rose) Angina Questionnaire in Cardiovascular Epidemiology

Abstract: During 1978-80, 7735 men aged 40-59 took part in a screening examination which included an administered version of the WHO (Rose) questionnaire on chest pain. Those men who had 'possible' angina were as likely to have an ischaemic electrocardiogram at rest as those with 'definite' angina. Furthermore, the heart attack rate over 7.5 years was similar in men with 'definite' and 'possible' angina and did not diminish with length of follow-up. Five years after the initial screening 98% of the surviving men replied to a postal questionnaire which included a self-administered version of the chest pain questionnaire. Age-specific prevalence rates of angina based on the administered questionnaire at screening and on the self-administered postal version five years later, were similar. Men who had angina ('definite' or 'possible') on both occasions had the highest prevalence rate of ischaemic electrocardiograms, men who were positive on only one occasion had intermediate rates and those who were negative on both occasions had the lowest rates. We conclude that in cardiovascular studies of middle-aged men which use the WHO (Rose) questionnaire for the purposes of determining prevalence or assessing risk of a heart attack, angina should include both 'possible' and 'definite' angina.

Gallstone Growth, Size, and Risk of Gallbladder Cancer: An Interracial Study

Abstract: To investigate gallstone size, growth, and the relation between stone size and gallbladder cancer we have used cholecystectomy reports from 1676 female subjects (169 Whites, 531 Blacks, and 976 Native American Indians). Although the prevalence of gallstones differs markedly in these groups it appears that the estimated growth rate of gallstones in younger subjects, 2.0 mm per year (95% confidence interval: 1.7-2.3 mm) is homogeneous for all three groups. In both Indian and non-Indian populations the proportion of small stones diminished and the proportion of large stones increased over time. We found a strong relationship between gallstone size and gallbladder cancer. Large stones (greater than or equal to 3 cm) were found in 40% of patients with gallbladder cancer but in only 12% of all subjects of similar age. The relative risk for gallbladder cancer in subjects with stones greater than or equal to 3 cm was 9.2 compared with subjects with stones less than 1 cm. (95% confidence interval: 2.3-37). We estimate that one-third of all gallbladder cancers in subjects with calculi will be associated with large (greater than or equal to 3 cm) stones. We believe that stone size might be used to determine the risk of gallbladder cancer in patients with gallstones.

WHO MONICA Project: objectives and design.

Abstract: The WHO MONICA Project is a multicentre international collaborative project coordinated by the World Health Organization. Its objective is to measure trends in cardiovascular mortality and morbidity and to assess the extent to which these trends are related to changes in risk factor levels and/or medical care, measured at the same time in defined communities in different countries. Thirty-nine collaborating centres from 26 countries of Europe, North America, and the Western Pacific collaborate in this project, using a standardized protocol and covering a population of approximately 10 million men and women aged 35-64. The WHO MONICA Project is directed by the Council of Principal Investigators and a Steering Committee, and it is managed by a Management Centre, Data Centre, Quality Control Centres (for event registration, ECG coding and lipid determinations) and Reference Centres (for optional studies). The MONICA methodology is increasingly used as a measurement tool for cardiovascular and non-communicable diseases prevention and control programmes by centres within and outside the project.

Risk Factors for Sudden Infant Death Syndrome in the US Collaborative Perinatal Project

Abstract: Risk factors for sudden infant death syndrome (SIDS) were studied among infants born to the nearly 56,000 women enrolled in the US Collaborative Perinatal Project from 1959 through 1966. The 193 SIDS cases identified in the cohort were compared with 1930 controls randomly selected from infants who survived the first year of life. The previously documented excess risk associated with black race disappeared after adjusting for maternal education and family income. Maternal smoking, maternal anaemia during pregnancy, and lack of early prenatal care were all positively associated with SIDS. After adjustment for gestational age, infants with low weight and length at birth were still at increased SIDS risk, suggesting that intrauterine growth retardation may be a risk factor. Neurological abnormalities diagnosed before death were associated with SIDS, but much of the association was removed by adjusting for birthweight. The negative association of breastfeeding with SIDS was much reduced upon adjustment by maternal education and birthweight. These findings may have important implications in our understanding of the epidemiology of SIDS.

Prediagnostic Serum Selenium in a Case-Control Study of Thyroid Cancer

Abstract: Sera from 43 persons who developed thyroid cancer on an average 4.8 years after blood sampling were compared with sera from controls. Three controls per case matched for sex, age, place of residence and year of blood sampling, with regard to serum selenium and serum copper. Cases were significantly lower in serum selenium than controls, and the estimated odds ratio of thyroid cancer increased from 1 for levels greater than or equal to 1.65 mumol/l, to 6.1 for levels 1.26-1.64 mumol/l, to 7.7 for levels less than or equal to 1.25 mumol/l. When time from blood sampling to diagnosis of the case was considered, it could be shown that the protective effect of high serum selenium concentrations was restricted to the last (less than 7) years prior to the diagnosis of thyroid cancer. The serum selenium concentration of cases tended to decrease relative to controls the shorter time was from blood sampling to the diagnosis. There was no difference between cases and controls with regard to serum copper.

Comparison of a Food Frequency Questionnaire with a Diet Record

Abstract: The associations between levels of nutrients derived from a 24-hour diet record and a food frequency questionnaire were assessed in a sample of 433 men and women. The food frequency questionnaire was administered three years after the completion of the diet record. Spearman correlations were all statistically significant; they varied from 0.36 for energy to 0.15 for vitamin A. Comparison of distributions into fifths showed few people grossly misclassified. A model was developed to assess the correlations which would be expected under various conditions of within and between subject variance for each nutrient, errors in measurements and drift in intake over time. The best possible correlation that could be obtained using the within and between subject variations in intake previously published, and with no measurement error or drift over time, was 0.60 for energy and 0.34 for vitamin A. Using a realistic measure of measurement error (standard deviation on log scale of 0.12 for diet record method, 0.06 for drift over time and 0.18 for food frequency method) the correlations obtained in the modelling were very similar to that observed. This study shows that it may be appropriate to use a food frequency questionnaire instead of a diet record to estimate intakes in population based epidemiological studies.

Serum Fatty Acids and Fish Intake in Rural Japanese, Urban Japanese, Japanese American and Caucasian American Men

Abstract: To examine the relationship of fish intake with serum fatty acids cross-culturally, we surveyed a total of 136 men aged 34 to 55 years in four different populations: rural Japanese (RJ), urban Japanese (UJ), Japanese Americans (JA), and Caucasian Americans (CA). Mean levels of estimated total fish intake per day were 124.9 g in RJ, 70.8 g in UJ, 45.7 g in JA, and 32.3 g in CA. The percentage of total serum fatty acids contributed by omega-3 polyunsaturated fatty acids in these populations was 11.8% in RJ, 9.0% in UJ, 3.4% in JA and 2.5% in CA. Means of omega-3 fatty acids and intake of fish were correlated at the population level; this relationship was strongest when intake of dark-meat fish was considered (n = 4, r = 0.979, p = 0.02). Within each population, except for UJ, individual omega-3 fatty acid levels and dark-meat fish intake were significantly associated (p less than 0.05). A 20 g increase in dark-meat fish consumption was associated with an estimated relative increase in omega-3 fatty acid content of serum by 0.76% in RJ, 0.75% in UJ, 0.64% in JA, and 0.22% in CA. The association between fish intake and serum omega-3 fatty acids at the individual level was not explained by other coronary risk factors. Mortality from coronary heart disease is much lower in Japan than in the US. Population differences in fish intake and serum omega-3 fatty acid levels may contribute to the population difference in the risk of coronary heart disease.

Socioeconomic Indicators, Tobacco and Alcohol in the Aetiology of Digestive Tract Neoplasms

Abstract: The relationship between education, social class, smoking habits, alcohol consumption and the risk of digestive tract neoplasms was analysed in a case-control study of 50 cases of cancer of the mouth or pharynx, 209 of the oesophagus, 397 of the stomach, 455 of the colon, 295 of the rectum, 151 of the liver, 214 of the pancreas, and a total of 1944 control subjects admitted for acute, non-neoplastic or digestive tract disorders. Cancers of the mouth or pharynx, oesophagus and stomach were inversely and strongly related to education, with risk estimates ranging between 0.2 and 0.4 for the highest education categories. Significant, but weaker inverse relations were evident for rectal and liver cancer, too, whereas the risk of colon cancer was elevated among more educated individuals. There was no relationship between education and pancreatic cancer. The pattern of risk was largely comparable when the head of the household's occupation was used as indicator of social class. There were strong direct associations between cigarette (as well as pipe or cigar) smoking and cancers of the mouth or pharynx and oesophagus, and a moderate one with pancreatic cancer, but none of the other sites considered was related to smoking habits. Cancers of the mouth or pharynx and oesophagus were independently and strongly related to alcohol consumption, too, while the associations between alcohol and liver or pancreatic cancer were moderate and not significant. Cancers of the stomach, colon and rectum were unrelated to measures of alcohol consumption.

Mothers' Personal and Domestic Hygiene and Diarrhoea Incidence in Young Children in Rural Bangladesh

Abstract: This study examines the effect of maternal personal and domestic hygiene on the incidence of diarrhoea in children aged 6-23 months from rural areas around Teknaf, Bangladesh. The intervention area received augmented water supply through handpumps and health education while the control area received no project inputs. From July 1980 to June 1983, diarrhoea incidence was recorded weekly while mothers' personal and domestic hygiene was observed yearly. Annual incidence of diarrhoea in 314 children from the intervention area and 309 children from the control area was analysed in relation to maternal personal and domestic hygiene, controlling for education and occupation of household head and household size. Results show that, in both areas, use of handpump water for drinking and washing, removal of child's faeces from the yard, and maternal handwashing before handling food and after defaecation of self and child, observed together, decreased yearly diarrhoea incidence in children by more than 40% compared to children living in households where none or only one of these practices was observed.

Trends in CHD Mortality, Morbidity and Risk Factor Levels from 1960 to 1986: The Minnesota Heart Survey

Abstract: The Minnesota Heart Survey (MHS) assessed population trends in coronary heart disease (CHD) mortality, morbidity and risk factor levels in the Twin Cities metropolitan area to explain the decline in CHD deaths. Age-adjusted CHD mortality rates declined in Twin Cities residents aged 30 to 74 from 1968 to 1986 by 52% in men and 58% in women. Much of the decline in CHD mortality was attributable to decreased out-of-hospital deaths. Attack rates based on hospitalized definite myocardial infarction (MI) did not change from 1970 to 1985, and hospital case-fatality rates declined consistently from 1970 to 1985 (from 21% to 11% in men, from 27% to 17% in women). Dramatic increases were noted in the percentage of patients undergoing cardiac procedures (coronary artery bypass, angioplasty, and thrombolytic agents). Trends in CHD rates were associated with improved population levels of risk factors. Average serum total cholesterol levels decreased by 8 mg/dl and 11 mg/dl between 1973 and 1987 in men and women, respectively. Cigarette smoking prevalence declined from approximately 40% to 30%. Average systolic blood pressure apparently declined about 1 mm Hg and diastolic blood pressure by 2 mm Hg from 1973 to 1987. Body mass index (wt/ht2) increased by 1 unit in men and 1.7 units in women from 1973 to 1987. These data suggest that a combination of primary prevention and improved medical care of acute CHD contributed to the decline in CHD mortality.

Risk Factors for Deaths due to Respiratory Infections among Brazilian Infants

Abstract: In a population based case-control study, 127 Brazilian infants who died due to a respiratory infection were compared with 254 neighbourhood controls. The main risk factors associated with mortality were low socioeconomic status (including low levels of parental education) and--after adjustment for socioeconomic status--lack of breastfeeding, lack of supplementation with non-milk foods, crowding, the number of under-fives in the family, lack of a flush toilet, low birthweight, low weight-for-age and having a young mother. In a multivariate analysis, the variables found to be most closely associated with mortality were breastfeeding, education of the father, the number of under-fives, family income and birthweight. Having a low weight-for-age was also strongly associated with mortality but the retrospective nature of the study makes this finding difficult to interpret.

Case-Control Studies of Cancer in New Zealand Electrical Workers

Abstract: A series of reports, including a New Zealand case-control study, have suggested that electrical workers are at increased risk of leukaemia. We report here a further series of case-control studies based on the New Zealand Cancer Registry. These involved 19,904 male patients registered with cancer for the period 1980-1984 who were aged 20 years or more at time of registration. For each cancer site, the registrations for other sites formed the control group. Three main findings emerged. First, there is an elevated leukaemia risk in New Zealand electrical workers (odds ratio (OR) = 1.62, 95% confidence interval (Cl) 1.04-2.52), but little evidence of increased risks for other cancer sites. Second, contrary to other published studies, the increased risk was primarily for chronic leukaemia (OR = 2.12) rather than acute leukaemia (OR = 1.25), and for lymphatic leukaemia (OR = 1.73) rather than myeloid leukaemia (OR = 1.22). Third, the increased risk was strongest for certain categories of electrical work including radio and television repairers (OR = 7.86, 95% CI 2.20-28.09), electricians (OR = 1.68, 95% Cl = 0.75-3.79), linemen (OR = 2.35, 95% Cl 0.97-5.70) and power station operators (OR = 3.89, 95% Cl 1.00-15.22).

Pattern of Poisoning in Rural Sri Lanka

Abstract: An epidemiology study of poisoning was done in a geographically defined area in rural Sri Lanka, a developing agricultural country The incidence of poisoning was 75 per 100,000 population and the death rate was very high (22 per 100,000 population) Both were highest in the age group 15-34 and there were significant ethnic differences in the incidence of poisoning Agrochemicals were responsible for 59% of all poisonings Paraquat was the commonest poisoning agent with a high fatality rate of 68% Use of highly toxic agents may have resulted in deaths where there was no intention to commit suicide Strict legislation regarding the sale, distribution and storage of agrochemicals could result in the reduction of mortality and perhaps the incidence of poisoning, in developing agricultural countries

Analysis of the Household Distribution of Trachoma in a Gambian Village Using a Monte Carlo Simulation Procedure

Abstract: Studies on the household distribution of trachoma have reached conflicting conclusions. This paper describes a cross-sectional survey of endemic trachoma in a Gambian village. Cases of active trachoma were mapped, and the compound and household distribution of the disease analysed by a Monte Carlo simulation procedure which takes into account differences in the size and age distribution within individual households. Significant clustering of active trachoma cases both by village compound (p less than 0.0001) and bedroom (less than 0.05) were detected supporting the concept that intra-familial transmission of trachoma is important. There was no evidence of spatial clustering of rooms with higher than expected prevalence of trachoma. Clustering of disease in space or time provides important evidence of infectious aetiology and route of transmission. The methods discussed here are generally applicable in the study of other infectious diseases.

Cancer Risks in New Zealand Farmers

Abstract: Previous New Zealand case-control studies have found increased risk for leukaemia, non-Hodgkin's lymphoma (NHL) and multiple myeloma in farmers. We report here a further series of New Zealand Cancer Registry based case-control studies of farming and site-specific cancer risks. These involved 19,904 males aged 20 years or more who were registered with cancer between 1980 and 1984. For each cancer site, the registrations for other sites formed the control group. Farmers had elevated risks for malignant melanoma (Odds Ratio [OR] = 1.25, 95% confidence interval [Cl] 1.05-1.50), and for cancer of the lip (OR = 2.43, 95% Cl 1.81-3.27), rectum (OR = 1.19, 95% Cl 1.03-1.38), bone (OR = 1.95, 95% Cl 1.00-3.80), prostate (OR = 1.26, 95% Cl 1.13-1.41) and brain (OR = 1.34, 95% Cl 1.04-1.74). Decreased risks were observed for cancer of the larynx (OR = 0.66, 95% Cl 0.45-0.96), lung (OR = 0.70, 95% Cl 0.63-0.77) and testis (OR = 0.58, 95% Cl 0.39-0.88). Livestock farmers had a relatively high risk for brain cancer, while the risk for cancer of the lip was highest among dairy farmers. Farmers also had increased risks for cancer of the lymphatic and haematopoietic system (International Classification of Disease 9th edn (ICD) 200-208) (OR = 1.24, 95% Cl 1.08-1.42), leukaemia (OR = 1.24, 95% Cl 0.99-1.55) and non-Hodgkin's lymphoma (NHL) (OR = 1.24, 95% Cl 0.99-1.56), as described previously.

WHO MONICA Project: assessing CHD mortality and morbidity.

Abstract: In the WHO MONICA Project mortality and morbidity from acute myocardial infarction is being monitored in 39 Collaborating Centres in 26 countries for a period of 10 years. The myocardial infarction registration procedures have been standardized and suspect coronary events are classified into diagnostic categories according to common criteria. This paper presents ischaemic heart disease mortality figures, based on routine statistics for the study populations and discusses cross-sectional comparability of morbidity data from event registration. Because of differences in availability of data used for diagnostic classification of events (such as autopsy data) the proportions of different diagnostic categories vary from centre to centre. There are, therefore, problems in cross-sectional comparison of morbidity data between the centres. The primary target of event registration in the project is to monitor morbidity changes within centres during the ten-year period. This goal should not be affected by the problems described in this paper.

Incidence of childhood cancer in Denmark 1943-1984.

Abstract: A population-based study was carried out on 5790 tumours in children (aged 0-14 years) diagnosed in the period 1943-1984 in Denmark. Cases were identified from the files of the high-quality National Cancer Registry in which codes for tumours were based solely on topography until the end of 1977. To achieve a uniform data set following the outlines of the International Classification of Diseases for Oncology (ICD-O) coding system used by the Cancer Registry today, all cases of childhood cancer diagnosed prior to 1978 were re-evaluated, and an ICD-O code was applied. Tumours were aggregated into diagnostic groups suitable for analysis and presentation using an internationally agreed scheme, which was designed by the Manchester Children's Tumour Registry and modified recently by the International Agency for Research on Cancer. The average incidence rates for all histological types of childhood cancer combined were 137 per million boys and 111 per million girls, which are close to those reported from the USA but higher than most of the overall figures reported from Europe. The proportions of specific tumours were similar to those observed in other industrialized countries. The well known excess of cancer cases among boys compared to girls was due mainly to the occurrence of 90% more lymphomas, 30% more leukaemias and 15% more tumours of the central nervous system (CNS) among boys. Although significant increases were seen in the subgroups of CNS neoplasms and neuroblastomas (both sexes) and of lymphomas (boys only), no overall increase in childhood cancer was observed during the 42-year period of registration. While the increase in the incidence of CNS tumours was explained at least partly by better cancer surveillance, no interpretation can be offered for the increases seen for neuroblastomas and lymphomas. Our descriptive data suggest that environmental exposures do not play any significant role in the aetiology of the majority of childhood cancers.

Alcohol Dose, Frequency and Age at First Exposure in Relation to the Risk of Breast Cancer

Abstract: Habitual alcohol consumption, in terms of dose and frequency, average daily intake, as well as drinking alcohol at age 25 were compared between 120 incident breast cancer cases and 164 population controls in The Netherlands. Dietary and lifestyle factors, past and present alcohol consumption were established in 1985-1987 in home interviews. In premenopausal women a protective effect of low alcohol consumption (1-4 g/day) as compared to non-drinkers was suggested. The multivariate adjusted odds ratio (OR) comparing women drinking greater than or equal to 30 g with women drinking 1 to 4 g alcohol daily was 8.5 (95% confidence interval: (Cl) = 1.1-65.1). The OR for a dose of alcohol of greater than or equal to 15 g versus 1-14 g was 4.0 (Cl = 1.0-15.6) and for drinking more versus less than three times a week the OR was 2.8 (Cl = 0.8-9.8). In post-menopausal women no association was observed between recent drinking habits and breast cancer risk. In these women, however, the adjusted OR for drinking alcohol before the age of 25 was 2.4 (Cl = 1.0-5.6). Although causal inference is hampered by the cultural aspects of drinking habits, the results suggest that moderate drinking does not increase risk. Drinking more than 30 g daily or a high dose may enhance risk in premenopausal women. Furthermore, an early start to drinking alcohol may increase the relative risk for breast cancer even beyond menopause.

Trends in CHD in the United States

Abstract: Coronary heart disease (CHD) death rates increased in the United States until the mid 1960s then declined. Declines were greater for acute myocardial infarction (AMI), for younger age groups, for the white population, and for higher socioeconomic groups. Trends in incidence are uncertain but in-hospital fatality rates have decreased. There have been major advances in diagnosis, prevention and treatment of CHD, and numbers of internists and cardiologists, emergency medical services, and coronary care units have increased. New potent medical and surgical treatments for acute and chronic CHD have been introduced. Reductions in risk factors include decreases in cigarette smoking especially among men, falls in mean systolic blood pressure, rises in the proportion of hypertensive adults who are treated and controlled, and reductions in plasma cholesterol. Consumption of whole milk, butter, and eggs decreased whereas use of low fat milk, cooking oils, poultry, fish, vegetables, and fruits increased. However, the prevalence of obesity has increased. CHD is still the leading cause of death, and its prevalence is expected to rise as the population increases at older ages and treatment prolongs survival of patients with CHD.

Short-Term Effects of Sulphur Dioxide Pollution on Mortality in Two French Cities

Abstract: To assess the short-term effects of sulphur dioxide (SO2) atmospheric pollution on mortality a study was conducted in two large French cities, using daily measures of pollution and mortality. A statistically significant association between daily SO2 pollution and respiratory deaths up to 10 days later was shown in both cities for both male and female populations together in the age group 65 years and over. No coherent results were found between SO2 pollution and cardiovascular deaths, or between suspended particulates and either respiratory or cardiovascular deaths. Particular emphasis was put on the use of correct statistical procedures using time series analysis and on the comparison of the part played by SO2 or suspended particulates on mortality.

Socioeconomic Status in Childhood Asthma

Abstract: This study examines the relationship between socioeconomic status (SES) and asthma prevalence and the use of asthma medication. One thousand and fifty European children aged eight and nine years were studied by parent completed questionnaire and histamine inhalation challenge. After controlling for sex of the child and for smokers in the house there were significantly higher lifetime (P = 0.029) and current (P = 0.046) prevalence rates of wheeze in children in low SES groups. There was no relationship between SES and asthma diagnosis, bronchial hyperresponsiveness (BHR: PD20 less than 7.8 mumol), or any combination of BHR with symptoms or diagnosis. The use of bronchodilators and asthma prophylactic drugs was less frequent in the low SES groups of children with wheeze in the last 12 months both with concurrent BHR or irrespective of BHR than in those in high SES groups.