Secular trends in cardiovascular risk factors: an age-period cohort analysis of 698,954 health examinations in 181,350 Austrian men and women.

OBJECTIVES: It is well established that morbidity and mortality patterns in cardiovascular diseases vary strongly over time, yet the determinants of such trends remain poorly understood. To assess the potential contribution of secular or cross-generation patterns, we evaluated birth cohort-related trends across the 20th century of risk factors in a large database of Austrian men and women. SUBJECTS AND SETTING: Trends in risk factors were investigated for 181,350 adults aged 20-79 years born between 1905 and 1975 undergoing 698,954 health examinations between 1985 and 2005 as participants of the Vorarlberg Health Monitoring and Promotion Programme. RESULTS: There was clear evidence of cohort-related shifts in all risk factors. Total serum cholesterol and triglyceride declined markedly, particularly in the youngest cohorts, as did systolic and diastolic blood pressure in both men and women. By contrast, fasting glucose showed a strong rising tendency in both sexes and at all ages, most markedly in young males. Average glucose levels were between 4 and 15 mg dL(-1) higher in individuals at the same age born 20 years later. In males, body weight expressed in kg m(-2) (body mass index) was increasing as well; however, in women, patterns were most marked at the 90th percentile. CONCLUSION: These findings provide strong evidence of population wide secular shifts and suggest that in addition to period influences, most probably through treatment intervention and lifestyle change, determinants across the life-course are programming shifts from childhood onwards.

The "Americanisation" of migrants: evidence for the contribution of ethnicity, social deprivation, lifestyle and life-course processes to the mid-20th century Coronary Heart Disease epidemic in the US.

We investigated the contribution of the large-scale immigration of White Europeans into the US between 1850 and 1930 to the timing and extent of the epidemic pattern of heart disease between 1900 and 1980. The analyses are based on data collected through the United States Federal Census from 1850 to the present. The hardcopy historical record confirms that census reports themselves and related monographs were concerned from 1850 with excessive mortality from heart disease of immigrants, particularly of Northern European origin and initially at least, their first-generation native-born children. Our analysis of the electronic database indicates a strong relationship between the percentage of US population foreign born and native born of foreign parentage and age adjusted mortality from heart disease. We identified a lag of 50 years giving the maximum linear correlation coefficient for men (r(2) = 0.92), and for women a shorter lag of 38 years and an earlier decline in Coronary Heart Disease (CHD) rates (r(2) = 0.96). Both the rise and fall of the CHD epidemic over an 80-year period correspond closely to the rise and fall of the foreign population in previous years. For the foreign born only, age adjusted negative binomial general estimated equation (GEE) models calculate the relative risk of dying of heart disease per 10% increase in proportion foreign born. There is an independent influence for men until 1930 and for women throughout the period from 1910 onwards. We conclude there is an impact of immigration on the pattern of the epidemic, mediated through a combination of factors, such as accumulated life-course susceptibility, deprived socio-economic conditions upon arrival, and the enthusiastic uptake of behaviours related to the classic risk factors of smoking, high saturated fat and salt diet. Our analysis provides a more contextualised understanding of the scale and timing of the epidemic of CHD in the US.