Contribution of smoking to socioeconomic inequalities in mortality: a study of 14 European countries, 1990-2004

BACKGROUND

Smoking contributes to socioeconomic inequalities in mortality, but the extent to which this contribution has changed over time and driven widening or narrowing inequalities in total mortality remains unknown. We studied socioeconomic inequalities in smoking-attributable mortality and their contribution to inequalities in total mortality in 1990-1994 and 2000-2004 in 14 European countries.

METHODS

We collected, harmonised and standardised population-wide data on all-cause and lung-cancer mortality by age, gender, educational and occupational level in 14 European populations in 1990-1994 and 2000-2004. Smoking-attributable mortality was indirectly estimated using the Preston-Glei-Wilmoth method.

RESULTS

In 2000-2004, smoking-attributable mortality was higher in lower socioeconomic groups in all countries among men, and in all countries except Spain, Italy and Slovenia, among women, and the contribution of smoking to socioeconomic inequalities in mortality varied between 19% and 55% among men, and between -1% and 56% among women. Since 1990-1994, absolute inequalities in smoking-attributable mortality and the contribution of smoking to inequalities in total mortality have decreased in most countries among men, but increased among women.

CONCLUSIONS

In many European countries, smoking has become less important as a determinant of socioeconomic inequalities in mortality among men, but not among women. Inequalities in smoking remain one of the most important entry points for reducing inequalities in mortality.

Lower Body vs. Upper Body Resistance Training and Arterial Stiffness in Young Men

Resistance training has been shown to increase arterial stiffness. The purpose of the present study was to examine and compare the systemic arterial stiffness responses to acute lower body (LRT) and upper body (URT) resistance training. 20 healthy young men [median age: 26 years (interquartile range 23, 32)] underwent LRT, URT and whole body resistance training (WRT). Before and immediately after, as well as 20, 40 and 60 min after each training session, we measured the cardio-ankle vascular index (CAVI) and brachial-ankle pulse wave velocity (baPWV) using VaSera VS-1500 N. We used mixed models for repeated measurements to estimate the post-exercise differences in CAVI and baPWV between the 3 resistance training modes. Immediately after exercise cessation, both CAVI and baPWV were lower for LRT compared with URT [CAVI: - 0.93 (95% confidence interval [CI] - 1.15, - 0.70); baPWV: - 2.08 m/s (95% CI - 2.48, - 1.67)]. Differences between LRT and URT gradually decreased during follow-up. Compared with WRT, LRT induced a decrease and URT an increase in arterial stiffness across all time points. In conclusion, LRT presents more favorable post-exercise arterial stiffness than URT. Our results suggest that LRT or WRT may be preferred over URT in individuals with impaired arterial stiffness.

Inverse association between circulating vitamin D and mortality--dependent on sex and cause of death?

BACKGROUND AND AIMS

In various populations, vitamin D deficiency is associated with chronic diseases and mortality. We examined the association between concentration of circulating 25-hydroxyvitamin D [25(OH)D], a marker of vitamin D status, and all-cause as well as cause-specific mortality.

METHODS AND RESULTS

The study included 3404 participants of the general adult Swiss population, who were recruited between November 1988 and June 1989 and followed-up until the end of 2008. Circulating 25(OH)D was measured by protein-bound assay. Cox proportional hazards regression was used to examine the association between 25(OH)D concentration and all-cause and cause-specific mortality adjusting for sex, age, season, diet, nationality, blood pressure, and smoking status. Per 10 ng/mL increase in 25(OH)D concentration, all-cause mortality decreased by 20% (HR = 0.83; 95% CI 0.74-0.92). 25(OH)D concentration was inversely associated with cardiovascular mortality in women (HR = 0.68, 95% CI 0.46-1.00 per 10 ng/mL increase), but not in men (HR = 0.97; 95% CI 0.77-1.23). In contrast, 25(OH)D concentration was inversely associated with cancer mortality in men (HR = 0.72, 95% CI 0.57-0.91 per 10 ng/mL increase), but not in women (HR = 1.14, 95% CI 0.93-1.39). Multivariate adjustment only slightly modified the 25(OH)D-mortality association.

CONCLUSION

25(OH)D was similarly inversely related to all-cause mortality in men and women. However, we observed opposite effects in women and men with respect to cardiovascular and cancer mortality.

[Prevalence of multimorbidity in Switzerland - definition and data sources]

Despite insufficient data, multimorbidity is in Switzerland an emerging issue on the agenda of public health and medical institutions. In this article the most current issues for and obstacles towards valid prevalence figures are discussed. Available Swiss data sources which could be used for estimating prevalence of multimorbidity are illustrated. The biggest current challenge for the international research community is to create a uniform definition of multimorbidity concerning the types and a minimal number of included chronic conditions. Furthermore, to obtain valid and internationally comparable prevalence estimates in the future, methodological approaches regarding data assessment and the development of a measurement for the burden of multimorbidity should be broadly discussed in order to come to a consensus.

Educational inequalities in tuberculosis mortality in sixteen European populations

OBJECTIVE

To describe the magnitude of socioeconomic inequalities in tuberculosis (TB) mortality by level of education in male, female, urban and rural populations in several European countries.

DESIGN

Data were obtained from the Eurothine Project, covering 16 populations between 1990 and 2003. Age- and sex-standardised mortality rates, the relative index of inequality and the slope index of inequality were used to assess educational inequalities.

RESULTS

The number of TB deaths reported was 8530, with a death rate of 3 per 100 000 per year, of which 73% were males. Educational inequalities in TB mortality were present in all European populations. Inequalities in TB mortality were greater than in total mortality. Relative and absolute inequalities were large in Eastern European and Baltic countries but relatively small in Southern European countries and in Norway, Finland and Sweden. Inequalities in mortality were observed among both men and women, and in both rural and urban populations.

CONCLUSIONS

Socio-economic inequalities in TB mortality exist in all European countries. Firm political commitment is required to reduce inequalities in the social determinants of TB incidence. Targeted public health measures are called for to improve access to treatment of vulnerable groups and thereby reduce TB mortality.

Prevalence of obesity in Switzerland 1992-2007: the impact of education, income and occupational class

Prevalence of excess weight varies substantially by socioeconomic position (SEP). SEP can be defined with different indicators. The strength of the association of SEP with excess weight differs by SEP indicator, between populations and over time. We examined the prevalence of overweight and obesity (body mass index 25-29.9 and ≥30 kg m(-2) ) in Switzerland by educational level, household income tertile and occupational class (three categories for each indicator). Self-reported data stem from four cross-sectional population surveys including 53 588 persons aged between 25 and 74 years. The overall prevalence of overweight increased between 1992 and 2007 from 37.4% to 41.4% in men and from 18.8% to 21.9% in women. Obesity prevalence increased from 7.2% to 9.7% in men and from 5.4% to 8.6% in women. Inequalities were calculated with multivariable logistic regression. Inequalities were larger in women than in men and for obesity than for overweight. However, overweight and obesity inequalities did not significantly change over time, despite overall increasing prevalence. Although all SEP indicators were independently associated with excess weight, the association was strongest with education, particularly in women. Programmes and policies aimed at preventing excess weight should target individuals with low education early in life.

Firearm suicides and availability of firearms: the Swiss experience

This study aimed to examine the association between the availability of firearms at home, and the proportion of firearm suicides in Switzerland in an ecological analysis. The data series were analysed by canton and yielded a fairly high correlation (Spearman's rho=0.60). Thus, the association holds also at a sub-national level.

Excess weight in the canton of Zurich, 1992-2009: harbinger of a trend reversal in Switzerland?

BACKGROUND/OBJECTIVE

In Switzerland, as in most developed countries, there has been a growing prevalence of excess weight in recent decades. However, within the country there may be regional variations. We investigated whether the trends in excess weight prevalence in the largest urban region differed from that in the rest of German Switzerland (GS).

METHODS

We used individual data from four nationally representative Swiss Health Surveys (1992-2007) and from one survey conducted in the Canton of Zurich (ZH) in 2009. All studies used self-reported height and weight (18-74 years, N = 41 628). Prevalence rates of excess weight (BMI > or = 25 kg/m2) were age standardised and population weighted. Odds ratios (OR: normal vs. excess weight) were obtained with weighted multivariable logistic regression.

RESULTS

The prevalence of excess weight was lower in ZH than in GS, with increasing differences over time. In GS, OR increased in men (p trend 1992-2007 <0.001) and stagnated in women. In contrast, in ZH, OR stagnated in men and decreased in women (p trend 1997-2009 = 0.005). Within ZH, compared to the capital city, OR were higher in men in the less privileged part of the Metropolitan Area (p = 0.046) and in women not living in the Zurich Metropolitan Area (p = 0.049).

CONCLUSION

In ZH, the prevalence of excess weight stagnated in men and decreased after having reached a peak in 1997 in women. This is the first study showing a decrease in Swiss adults, a population with internationally low excess weight prevalence. There is room for speculation whether ZH is a harbinger of the future situation in other regions of Switzerland and possibly other developed countries.

Underestimation of obesity prevalence in Switzerland: comparison of two methods for correction of self-report

BACKGROUND/OBJECTIVE

Studies using self-report may underestimate obesity prevalence because participants tend to overestimate their height, underestimate their weight and thus seriously underestimate their Body Mass Index (BMI). In order to find ways to adjust for this misestimation, we tested two correction methods for self-report by comparing the derived obesity prevalence rates with those based on measured height and weight.

METHODS

We used individual data from six studies based on self-reported BMI (1980-2007, n = 46589) and from five studies based on measured BMI (1977-2004, n = 20130). All studies were population-based samples and carried out in Switzerland. We limited to men and women aged 35 to 74 years. Obesity was defined as BMI > or =30 kg/m2. For correction method one, we used a lower BMI cutoff of 29.2 kg/m2 (for both sexes) for the definition of obesity; for method two, we adjusted weight and height (respecting age and sex) using equations that were derived from another population. Results were age-standardised. Differences were measured with a logistic regression model considering random effects.

RESULTS

Adjustment of height and weight (method two) substantially approximated the BMI distribution based on unadjusted self-report to the BMI distribution based on measurement. In 2002/2003, obesity prevalence obtained with method two (men and women respectively: 16.3% and 13.0%) tended to be more similar to measured obesity prevalence (16.4% and 13.9%) than obesity prevalence obtained with method one (13.8% and 11.0%).

CONCLUSION

Equation adjustment of self-reported weight and height provides an approximation of the real (measured) BMI distribution by sex and age and has advantages over the use of a universal lower cutoff level to adjust for self-report. However, to appropriately adjust for self-report, a Swiss-specific equation should be developed based on measured and self-reported heights and weights of the same individuals.

Socioeconomic inequalities in diabetes mellitus across Europe at the beginning of the 21st century

AIMS/HYPOTHESIS

The aim of this study was to determine and quantify socioeconomic position (SEP) inequalities in diabetes mellitus in different areas of Europe, at the turn of the century, for men and women.

METHODS

We analysed data from ten representative national health surveys and 13 mortality registers. For national health surveys the dependent variable was the presence of diabetes by self-report and for mortality registers it was death from diabetes. Educational level (SEP), age and sex were independent variables, and age-adjusted prevalence ratios (PRs) and risk ratios (RRs) were calculated.

RESULTS

In the overall study population, low SEP was related to a higher prevalence of diabetes, for example men who attained a level of education equivalent to lower secondary school or less had a PR of 1.6 (95% CI 1.4-1.9) compared with those who attained tertiary level education, whereas the corresponding value in women was 2.2 (95% CI 1.9-2.7). Moreover, in all countries, having a disadvantaged SEP is related to a higher rate of mortality from diabetes and a linear relationship is observed. Eastern European countries have higher relative inequalities in mortality by SEP. According to our data, the RR of dying from diabetes for women with low a SEP is 3.4 (95% CI 2.6-4.6), while in men it is 2.0 (95% CI 1.7-2.4).

CONCLUSIONS/INTERPRETATION

In Europe, educational attainment and diabetes are inversely related, in terms of both morbidity and mortality rates. This underlines the importance of targeting interventions towards low SEP groups. Access and use of healthcare services by people with diabetes also need to be improved.

Suicide after bereavement: an overlooked problem

BACKGROUND

To examine the effect of time on suicide after bereavement among widowed persons.

METHOD

The data were extracted from Swiss mortality statistics for the period 1987-2005. The time between bereavement and subsequent death, specifically by suicide, was determined by linkage of individual records of married persons. The suicide rates and the standardized mortality ratios in the first week/month/year of widowhood were calculated based on person-year calculations.

RESULTS

The annualized suicide rates in widowed persons were highest in the first week after bereavement: 941 males and 207 females per 100,000. The corresponding standardized mortality ratios were approximately 34 and 19 respectively. In the first month(s) after bereavement, the rates and the ratios decreased, first rapidly, then gradually. Except in older widows, they did not reach the baseline levels during the first year after bereavement.

CONCLUSIONS

The suicide risk of widowed persons is increased in the days, weeks and months after bereavement. Widowed persons are a clear-cut risk group under the aegis of undertakers, priests and general practitioners.

Educational differences in cancer mortality among women and men: a gender pattern that differs across Europe

We used longitudinal mortality data sets for the 1990s to compare socioeconomic inequalities in total cancer mortality between women and men aged 30–74 in 12 different European populations (Madrid, Basque region, Barcelona, Slovenia, Turin, Switzerland, France, Belgium, Denmark, Norway, Sweden, Finland) and to investigate which cancer sites explain the differences found. We measured socioeconomic status using educational level and computed relative indices of inequality (RII). We observed large variations within Europe for educational differences in total cancer mortality among men and women. Three patterns were observed: Denmark, Norway and Sweden (significant RII around 1.3–1.4 among both men and women); France, Switzerland, Belgium and Finland (significant RII around 1.7–1.8 among men and around 1.2 among women); Spanish populations, Slovenia and Turin (significant RII from 1.29 to 1.88 among men; no differences among women except in the Basque region, where RII is significantly lower than 1). Lung, upper aerodigestive tract and breast cancers explained most of the variations between gender and populations in the magnitude of inequalities in total cancer mortality. Given time trends in cancer mortality, the gap in the magnitude of socioeconomic inequalities in cancer mortality between gender and between European populations will probably decrease in the future.

Socioeconomic status and ischaemic heart disease mortality in 10 western European populations during the 1990s

OBJECTIVE

To assess the association between socioeconomic status and ischaemic heart disease (IHD) mortality in 10 western European populations during the 1990s.

DESIGN

Longitudinal study.

SETTING

10 European populations (95,009,822 person years).

METHODS

Longitudinal data on IHD mortality by educational level were obtained from registries in Finland, Norway, Denmark, England/Wales, Belgium, Switzerland, Austria, Turin (Italy), Barcelona (Spain), and Madrid (Spain). Age standardised rates and rate ratios (RRs) of IHD mortality by educational level were calculated by using Poisson regression.

RESULTS

IHD mortality was higher in those with a lower socioeconomic status than in those with a higher socioeconomic status among men aged 30-59 (RR 1.55, 95% confidence interval (CI) 1.51 to 1.60) and 60 years and over (RR 1.22, 95% CI 1.21 to 1.24), and among women aged 30-59 (RR 2.13, 95% CI 1.98 to 2.29) and 60 years and over (RR 1.36, 95% CI 1.33 to 1.38). Socioeconomic disparities in IHD mortality were larger in the Scandinavian countries and England/Wales, of moderate size in Belgium, Switzerland, and Austria, and smaller in southern European populations among men and younger women (p < 0.0001). For elderly women the north-south gradient was smaller and there was less variation between populations. No socioeconomic disparities in IHD mortality existed among elderly men in southern Europe.

CONCLUSIONS

Socioeconomic disparities in IHD mortality were larger in northern than in southern European populations during the 1990s. This partly reflects the pattern of socioeconomic disparities in cardiovascular risk factors in Europe. Population wide strategies to reduce risk factor prevalence combined with interventions targeted at the lower socioeconomic groups can contribute to reduce IHD mortality in Europe.

Education level inequalities and transportation injury mortality in the middle aged and elderly in European settings

OBJECTIVE

To study the differential distribution of transportation injury mortality by educational level in nine European settings, among people older than 30 years, during the 1990s.

METHODS

Deaths of men and women older than 30 years from transportation injuries were studied. Rate differences and rate ratios (RR) between high and low educational level rates were obtained.

RESULTS

Among men, those of low educational level had higher death rates in all settings, a pattern that was maintained in the different settings; no inequalities were found among women. Among men, in all the settings, the RR was higher in the 30-49 age group (RR 1.46, 95% CI 1.32 to 1.61) than in the age groups 50-69 and > or = 70 years, a pattern that was maintained in the different settings. For women for all the settings together, no differences were found among educational levels in the three age groups. In the different settings, only three had a high RR in the youngest age group, Finland (RR 1.33, 95% CI 1.01 to 1.74), Belgium (RR 1.38; 95% CI 1.13 to 1.67), and Austria (RR 1.49, 95% CI 0.75 to 2.96).

CONCLUSION

This study provides new evidence on the importance of socioeconomic inequalities in transportation injury mortality across Europe. This applies to men, but not to women. Greater attention should be placed on opportunities to select intervention strategies tailored to tackle socioeconomic inequalities in transportation injuries.

[Mortality from malignant melanoma: epidemiological trends in Switzerland]

The skin doesn't forget damage by sun exposure (sunburn, ultraviolet radiation). Indeed, melanoma mortality increases quite linearly with rising age. For Swiss nationals the sex ratio of mortality rates is 1.7, i.e. risks for male foreigners and Swiss females are of similar size. However, in younger Swiss men (35 to 44 years) mortality rates between 1979/83 and 1997/2001 diminished by 66% (p < 0.02). Analyses of mortality by occupational groups revealed that indoor working males like graduates and employees with commercial or technical education have an increased risk. The results support the association between melanoma risk and intermittent sun exposure, outdoor workers with chronic sunlight exposure being slightly protected. Further declines in mortality may be expected with skin cancer prevention campaigns improving sun exposure behaviour.

Socioeconomic inequalities in mortality among elderly people in 11 European populations

STUDY OBJECTIVE

To describe mortality inequalities related to education and housing tenure in 11 European populations and to describe the age pattern of relative and absolute socioeconomic inequalities in mortality in the elderly European population.

DESIGN AND METHODS

Data from mortality registries linked with population census data of 11 countries and regions of Europe were acquired for the beginning of the 1990s. Indicators of socioeconomic status were educational level and housing tenure. The study determined mortality rate ratios, relative indices of inequality (RII), and mortality rate differences. The age range was 30 to 90+ years. Analyses were performed on the pooled European data, including all populations, and on the data of populations separately. Data were included from Finland, Norway, Denmark, England and Wales, Belgium, France, Austria, Switzerland, Barcelona, Madrid, and Turin.

MAIN RESULTS

In Europe (populations pooled) relative inequalities in mortality decreased with increasing age, but persisted. Absolute educational mortality differences increased until the ages 90+. In some of the populations, relative inequalities among older women were as large as those among middle aged women. The decline of relative educational inequalities was largest in Norway (men and women) and Austria (men). Relative educational inequalities did not decrease, or hardly decreased with age in England and Wales (men), Belgium, Switzerland, Austria, and Turin (women).

CONCLUSIONS

Socioeconomic inequalities in mortality among older men and women were found to persist in each country, sometimes of similar magnitude as those among the middle aged. Mortality inequalities among older populations are an important public health problem in Europe.

Alcohol consumption and gender in the 20th century: the case of Switzerland

Given the changes of gender roles in this century it is hardly justified to assume constant proportions of alcohol consumption for males and females. The purpose of the study was to reconstruct the consumption trends of males and females in Switzerland since the beginning of the 20th century. Cirrhosis mortality and survey data were used to disaggregate by sex the per capita alcohol consumption derived from sales data. The disaggregation of the per capita alcohol consumption based on liver cirrhosis mortality suggests that the evolution of alcohol consumption in Switzerland followed a parallel course for both sexes only until the 1930s. The low consumption during World War II and the evident increase until the beginning of the '60s seem to have resulted above all from the variations in consumption of beer by men. The decrease in total alcohol consumption observed since the '70s is also most probably due only to men; there is no indication of a decreasing consumption by women. The tendency of male and female consumption patterns to become more similar should be taken into account in the prevention of alcohol misuse.

[Changes in mortality in Switzerland since 1950. II. Regional differences within Switzerland]

OBJECTIVES

To examine regional variations in all-cause mortality in Switzerland around 1990 and trends since 1950. Special emphasis is placed on unfavourable aspects that have been identified by comparisons with international trends.

DATA AND METHODS

Descriptive analysis of Swiss mortality statistics taken from individual records (1969-94) and data published by the Swiss Federal Statistical Office (1949-68).

RESULTS

Swiss citizens aged between 15 and 79 years often show mortality ratios of 1.5 and more between the best and the worst of the 106 regions of Switzerland. In subjects aged under 50 years, relative risk ranges are even larger. However, the regional mortality patterns before and after 50 rarely correspond. Generally, the relative risk difference between the best and the worst regions has not diminished since 1950, whereas the geographical patterns have completely changed. Instead of an obvious rural-urban gradient in 1950, mortality rates are now highest in the largest cities and, at least in men, are at their lowest in the wealthy suburbs. On a larger scale (division into 9 geographical units), central Switzerland has changed significantly from clearly elevated mortality rates in 1950 into a decidedly favourable position in 1990. A contrast between German and French Switzerland has existed for many decades: in the younger and middle age groups the francophone part of Switzerland has a higher mortality rate than the German-speaking part, whereas at ages over 70 French Switzerland has lower rates than German Switzerland. In some urban areas of Switzerland, the turning-point from a decreasing to an increasing trend in the mortality risks of subjects aged 15-49 years was reached around 1960, occasionally resulting in age-specific rates being higher in 1990 than in 1950. This unfavourable partial trend has spread over most, but not all, of Switzerland since 1970. Even in subjects aged 25-34 years, the age group for which Switzerland has the worst relative position on an international scale, some parts of the country do not have elevated all-cause mortality rates, whereas for men in the largest cities mortality risks are more than three times as high as in Japan. The deaths from "external" causes (mainly accidents and suicide) show marked geographical patterns within Switzerland; however, in all parts of the country, deaths from this group are much more frequent than, for example, in Italy or the Netherlands.

CONCLUSION

Geographical differences in mortality risks within Switzerland, as well as international disparities, suggest that there is a need for preventive measures in Switzerland, first and foremost concerning males aged 15-49 years and deaths from "external" causes.

[Development of mortality in Switzerland since 1950. I. International comparison and differences in sex, age and nationality]

BACKGROUND

All-cause mortality is an important criterion for assessing the health status and the living conditions of a population, thus indicating possible preventive measures.

DATA AND METHODS

Descriptive analyses of Swiss mortality records and a comparison with the WHO mortality data bank for the period since 1950.

RESULTS

Age-specific mortality trends in Switzerland are traced back to 1950 and compared with the situation in other European countries. At the beginning of the 1950s Swiss all-cause mortality rates were about the European average; now they are among the lowest worldwide. In most age classes, rates declined by more than one third between 1951/54 and 1990/94, in females even by more than 50%. This rather optimistic overall picture conceals less favourable partial trends. The decline in mortality rates in men aged 20-49 and women aged 20-34 years did not continue after 1970, and for males aged 20-44 and females aged 25-34 mortality risks have even increased in recent years. In both males and females, mortality rates from injury and poisoning (mainly accidents and suicide) exceed those of European low-incidence countries by 100%. On an international scale Swiss subjects aged between 15 and 44 years are at much higher risk, even when deaths from injury and poisoning, the most important cause of death in these ages, are excluded. When compared with their Swedish contemporaries, Swiss males aged 25-34 years have almost twice the risk of dying from a "natural" as well as from an "external" cause. As a rule, male/female sex ratios of mortality continued to increase, except in subjects aged 45-64 years.

CONCLUSION

In spite of low overall mortality risks, international age-specific rates suggest considerable potential for preventive measures in Switzerland. There is some evidence of substantial under-registration of the mortality risks of foreigners living in Switzerland. As foreigners represent a substantial part of the total population--with a maximum of 30% of men aged 25-34 years--figures for Switzerland as a whole may be biased seriously. Therefore, for mortality analyses and comparisons with international data, we suggest the study be restricted to Swiss citizens. When assessing mortality risks for foreigners in Switzerland alternative data sources and methods should be taken into account.

[Average life expectancy in Switzerland--historic and international background and thoughts on future development]

Age-specific mortality rates are a sensitive measure for the conditions of life in a population. Life tables--in Switzerland calculated approximately all ten years since 1876/80--indicate for any age and any observation period the mean life expectancy as well as the probabilities of death and survival, respectively. In the past centuries survival curves developed more and more a rectangular shape, but mortality rates didn't decrease uniformly in all age groups: until the first part of the twentieth century, increases in mean life expectancy were predominantly due to a rapid decline of infant and children's mortality; since the 1930s decreasing adults' mortality gained more importance, and not until the 1960s lower death rates in the population aged over 60 became a major component of prolonging the mean span of life. The nowadays favourable mortality situation of Switzerland within Europe started to emerge in the 1950s, predominantly due to declining mortality rates in the uppermost age groups. For the decades to come, experts predict a further substantial increase of mean life expectancy, in spite of actually rather unfavourable trends in the mortality rates of young adults. Consequently, the number of those aged over 65 and particularly those over 80 years will considerably increase till 2020, even if the scenarios of 1995 would prove to be too optimistic.

Exploration of interactions between prognostic factors of stage I malignant melanoma

While many studies have sought prognostic factors of malignant melanoma using multivariate survival models, the interaction between predictors has been much less studied. We have studied data from 1,560 patients with stage I melanoma collected at the Cancer Registry of the Canton of Zurich over the period 1980-1990 and explored interactions between predictors by identifying two separate multivariate Cox models for men and women and investigating two-way interactions between predictors in each model. Considerable differences between models for man and women were observed. In particular, in women a pronounced interaction between 'histology' and 'Clark level' was identified. Without this interaction 'histology' and 'Clark level' are not significant but when the interaction term was included both predictors become significant. Thus, omission of an interaction term may preclude the recognition of main effects ('masking'). For female patients with nodular tumours prognosis is essentially independent of Clark level. In contrast, for female patients with non-nodular tumours, prognosis was found to be strongly dependent on Clark level. In the case of Clark level 2 prognosis was extremely good: no patient was observed to die from melanoma. We conclude that it may be worth considering interaction terms. With large enough sample sizes it may be preferable to stratify patients into subgroups and to identify separate models for each stratum instead of having to cope with interactions of higher order.

[Occupation-specific indicators for strategic prevention in risk groups]

Using graphical representations to compare undistorted information it was attempted to bridge the gap between medicine and concerned risk-groups. Age-standardized mortality rates in 1979-1983 for 55 occupational groups (in 11 categories) of males aged 35 to 74 years were computed and compared to the Swiss national average; simultaneously the quantitative importance and the total mortality without accidents is shown for each occupational group: as an example the figure for lung cancer is reproduced. The elevated total mortality in the upper tertile of occupational groups is significantly explained by an increased risk of dying from circulatory or respiratory diseases, liver cirrhosis or malignancies of the lung, oropharynx, oesophagus or stomach. Foreseeable decrease of high-risk occupational groups will result in a further decline in mortality due to stomach cancer and cerebrovascular diseases in Switzerland.

Abscisic-acid-induced drought tolerance in Funaria hygrometrica Hedw

Three-week-old protonemata of Funaria hygrometrica Hedw. cultivated in Petri dishes tolerate slow drying (24 h to complete dryness) but not rapid drying (1h to complete dryness). Slowly dried mosses show, on a dry-weight basis, a sixfold increase in abscisic-acid (ABA) contents during the drying process. Rehydrated, slowly dried protonemata have the ability to tolerate subsequent rapid drying. When ABA is added to three-week-old protonemata at a concentration of 10 μM for 16 h, tolerance to rapid drying is induced. These data indicate that the induction of drought tolerance in Funaria hygrometrica is mediated by ABA. Mosses treated with ABA loose their water as fast as controls do; therefore, ABA does not act via reduced water loss. However, induction of synthesis of new proteins by ABA may form an important part of the drought tolerance because 10 μM cycloheximide inhibits the ABA-mediated tolerance to rapid drying.

Cloning and expression in Escherichia coli of opc, the gene for an unusual class 5 outer membrane protein from Neisseria meningitidis (meningococci/surface antigen)

A genomic library was constructed in a lambda gt11 vector using chromosomal DNA from a meningococcal serogroup A strain and plaques expressing the class 5C protein were recognized by screening with specific monoclonal antibodies. The opc insert was subcloned into a multicopy plasmid which induced expression of that protein in Escherichia coli as a surface-exposed major outer membrane protein. The nucleotide sequence of opc is typical of an outer membrane protein with a promoter and terminator region, a leader peptide which is cleaved during expression and a complete open reading frame. Unlike other meningococcal class 5 proteins or gonococcal P.II proteins, the sequence did not contain any pentanucleotide repeats and the sequence showed little homology to these other functionally related proteins. However, the predicted amino acid sequence of the mature protein for opc showed 27% similarity to that for a second opa gene cloned from the same meningococcal strain. This is the first report of cloning and expression of a functional meningococcal gene encoding a class 5 outer membrane protein in E. coli.

Variation in class 5 protein expression by serogroup A meningococci during a meningitis epidemic

Serogroup A meningococci were isolated from patients and healthy carriers in The Gambia between 1982 and 1988. The class 5 proteins expressed by these bacteria were identified by electrophoretic migration and by serologic tests. Three protein serologic groupings (seroclasses) called A (protein 5a), B (proteins 5b, 5d, or 5e), and C (protein 5c or 5C) were found among 331 bacterial isolates. The number of class 5 proteins expressed per isolate varied from none to four, with a median of two. The class 5 protein composition differed for certain paired isolates obtained from the nasopharynx, blood, and cerebrospinal fluid of diseased patients and for certain pairs of sequential isolates from the nasopharynx of healthy carriers; the medical relevance of this variation remains unclear, although the 5C protein was preferentially isolated from the nasopharynx and the 5a protein from diseased patients. The data show that a large proportion of healthy carriers in The Gambia were exposed to bacteria expressing each of the three seroclasses and that many people were exposed to bacteria expressing each of the three seroclasses and that many people were exposed to two or all three seroclasses during the epidemic of 1982-1983.

[Cartography as an instrument in epidemiology: methodologic considerations for the new Swiss cancer atlas]

Maps not following the syntactical rules of the graphical language entail the risk of being misunderstood. Maps aim at demonstrating spatial patterns and visualizing dividing lines. Representation of tabular values is not a principal goal. Maps should be "seen" as a whole, not be "read" element by element. Some technical aspects of cartography are discussed (distortion of information, grouping of data, adequacy and use of colour). The guidelines for the new Swiss cancer atlas are based on these general principles. A continuous-shading technique avoiding class intervals is being used. It allows the combination of maps and diagrams of different aggregations of the same data using a common shading scale. Indications of significance are integrated into all figures. Geographical maps are enriched by diagrams showing data for 9 cities, 5 language regions, for a grouping by size of community and for a socioeconomical classification of regions. The universal shading scale enables to compare the figures separately and crossways. Relationships not apparent in a traditional map might be revealed.