Objective: To construct a complex indicator, the Health Index, for the determination of the general health profile of the population and to assess the time trends of the latter in the male population of Tallinn, the capital of Estonia.
Design: Three epidemiological studies of cardiovascular diseases (CVD) risk factor involving independent random samples of the male population of Tallinn aged 30-59 y were carried out in 1981/82 (survey I), in 1984/85 (survey II) and in 1992/94 (survey III), the total number of participants was 5019. The screening procedure included standard epidemiological methods. The cohorts of the surveys I and II were followed up for 11 y on average; 457 deaths of cases were registered during that period. For the assessment of the general health profile of the population the Health Index was constructed on the basis of mortality follow-up data of the above mentioned two cohorts by means of the survival analysis methods using SAS (Statistical Analysis System). 20 variables were tested, 11 of them were selected as statistically significant for the prediction of total mortality: systolic blood pressure, heart rate, coronary heart disease (CHD) status (P < 0.0001), total cholesterol (TC), TC2, body mass index (BMI), BMI2, education, smoking, alcohol consumption (P < 0.01), marital status (P < 0.05). The predictive ability of the Health Index for CHD, CVD and total mortality was confirmed by analysing the age-adjusted relative risks according to the deciles of the Health Index.
Results: The Health Index was used to determine the general health profile of the male population of Tallinn aged 30-59 y at surveys I, II and III and for the assessment of its time trends between the three surveys (1981/82-1992/94). We have established an improvement of the health profile in the studied population from survey I to survey II and a further improvement for those aged over 40 y from the surveys II and III.
Conclusion: The Health Index should be regarded as a valuable tool for the assessment of health trends in the population. The mortality decline expected in this study was confirmed by observed mortality trends in the Estonian male population.