The Tampere adult population cardiovascular risk study (TAMRISK) is a prospective, longitudinal population based health survey study in Tampere, a city in southern Finland with a population of 210 000 [10, 11].
The Tampere city health care centre has provided regular PHEs, for screening and counselling, for the adult population of the city since 1980. All 40- and 50-year-old inhabitants have been invited to participate in these health surveys. During some periods, also 35- and 45-year-olds have been invited to participate. The PHE consisted of one 60-minute session with a public health nurse at the centre's health examination unit. In the session, the questionnaire information and screening tests were reviewed. Counseling was given on topics selected by the participant and also on findings of the screening tests.
Information is available for some participants for 15 years of consecutive 5-year follow-ups concerning risk factors for cardiovascular diseases, including family history, blood pressure, lipid values, smoking, waist circumference, diabetes exercise and eating habits. Also data on diseases has been recorded. Presently, invitations for the survey are sent to all subjects from Tampere that are 40 or 50 years old that year.
All subjects who had a self-reported diagnosis of hypertension and/or diabetes (made by a physician, n = 681) were chosen from a PHE 50-year-old cohort (n = 6000). Those subjects who also had information on 35-, 40-, and 45- year PHE formed the study group (n = 339). The control group included subjects from the same 50-year-old cohort who were apparently healthy, and had the same follow-up information. Controls were chosen for every subject in the study group by matching them according to sex (n = 604). Baseline clinical examinations had taken place during the calendar year when the subject caught the age of 35 in 1988–91. At the age of 40 the same subjects were invited to health examination again if they still lived in Tampere. This happened in 1993–96. The third follow up took place in 1998–2001 at the age of 45. The last follow up was in years 2003–06 at the age of 50. The follow-up time was 15 years. The Ethics Committees of the Tampere University Hospital and the City of Tampere approved the study. Written informed consent for participation in the study was obtained from all participants.
The basic evaluation in 1988–91 included an interview by a public health nurse. The interview was conducted using a structured questionnaire about health and health-related behavior, including questions about current and previous diseases. Information on current and previous diseases was based on self-report of diagnosis by a physician, including history of MI and diabetes. The questionnaire also assessed symptoms and ailments experienced within the past six months. These included questions of health in general and mental health. Questions of health-related behavior included current and past smoking. The frequency of physical exercise comprised both leisure and commute related activity. Quantitative estimation of the alcohol intake was carried out by using three structured questions to determine the amount and frequency of drinking. The total mean consumption of all alcoholic drinks was used, expressed as grams of pure ethanol per week. Physical examination included a single blood pressure (BP) measurement (mm of mercury) using a calibrated mercury sphygmomanometer. Serum total cholesterol (mmoles/liter) was measured by enzymatic techniques. Height (cm) and weight (kg) were recorded from which the body mass index was calculated.
The description of data was made by means and standard deviations for continuous variables and by proportions for categorical variables. The descriptions were constructed separately to the study group and controls. The differences in dichotomous variables were compared with Fisher's exact test, in other categorical variables with Chi-square test and in continuous variables with t-test, or Mann Whitney U test if the distribution was skewed. The analysis of variance for repeated measures was used to assess the differences in changes of body mass index and blood pressure between the study group and the control group during the follow up time. Normality of the distributions of the dependent variables were tested using Kolmogorov-Smirnov test, and logarithmic transformation was applied if the distribution of the variable was skewed. The changes were calculated in relation to the baseline measurement at the age of 40, 45 and 50. The model included the main effects of group factor and time, and their interaction. The baseline measurement of dependent variable was included in the model as a covariate. The risk level in the analyses was set equal to p-value of 0.05. Analyses were made using SPSS for Windows (version 16.0) program.