Liisa Keltikangas-Järvinen

Cohort Profile: The Cardiovascular Risk in Young Finns Study

In Finland, coronary heart disease (CHD) incidence was very high in the 1960s and 1970s. In line with this high incidence, the Seven Countries Study showed that the level of serum cholesterol in Finns was also the highest among the investigated countries in the 1960s. Because several studies indicated that the atherosclerotic process starts early in life, and in accord with the World Health Organization Recommendation of 1978 which stated that studies assessing atherosclerosis precursors in children should be initiated, a program was launched in Finland in the late 1970s to study cardiovascular risk in the youth. The Cardiovascular Risk in Young Finns Study was designed as a collaborative effort between five university departments of medical schools (i.e. in Helsinki, Kuopio, Oulu, Tampere and Turku) and several other institutions in Finland. The aim was to study the levels of CHD risk factors and their determinants in children and adolescents of various ages in different parts of the country. Two pilot studies were carried out in 1978 (N1⁄4 264, age 8 years) and in 1979 (N1⁄4 634, aged 3, 12 and 17 years). The first main cross-sectional (baseline) study was performed in 1980. The baseline study included 3596 children and adolescents aged 3, 6, 9, 12, 15 and 18 years. Between 1980 and 1992, these cohorts were followed up at 3-year intervals. The latest examination of the Cardiovascular Risk in Young Finns Study was performed in 2001, when the participants were young adults, aged 24–39 years. At the time of writing, the 27-year (i.e. 27 years since the start of the study when the participants are aged 30–45 years) follow-up field studies are being conducted, and will be completed in the beginning of 2008.

Workplace bullying and the risk of cardiovascular disease and depression

Aims: To examine exposure to workplace bullying as a risk factor for cardiovascular disease and depression in employees. Methods: Logistic regression models were related to prospective data from two surveys in a cohort of 5432 hospital employees (601 men and 4831 women), aged 18–63 years. Outcomes were new reports of doctor diagnosed cardiovascular disease and depression during the two year follow up among those who were free from these diseases at baseline. Results: The prevalence of bullying was 5% in the first survey and 6% in the second survey. Two per cent reported bullying experiences in both surveys, an indication of prolonged bullying. After adjustment for sex, age, and income, the odds ratio of incident cardiovascular disease for victims of prolonged bullying compared to non-bullied employees was 2.3 (95% CI 1.2 to 4.6). A further adjustment for overweight at baseline attenuated the odds ratio to 1.6 (95% CI 0.8 to 3.5). The association between prolonged bullying and incident depression was significant, even after these adjustments (odds ratio 4.2, 95% CI 2.0 to 8.6). Conclusions: A strong association between workplace bullying and subsequent depression suggests that bullying is an aetiological factor for mental health problems. The victims of bullying also seem to be at greater risk of cardiovascular disease, but this risk may partly be attributable to overweight.

Psychosocial stress and the insulin resistance syndrome

We examined the association between psychosocial stress-related variables and insulin resistance syndrome (IRS) risk-factor clustering. In 90 middle-aged male volunteers, psychosocial stress-related variables, defined as feelings of excessive tiredness and as personality and behavioral factors reflecting a stress-inducing life-style (type A behavior, hostility, and anger), were significantly correlated with the hyperinsulinemia, hyperglycemia, dyslipidemia, hypertension, increased abdominal obesity, and increased plasminogen activator inhibitor-1 (PAI-1) antigen comprising the IRS. The correlations remained significant after adjusting for body mass index (BMI), age, educational level, smoking status, alcohol consumption, and physical activity. However, the different stress-related factors reflected different risk-factor clustering profiles. Type A behavior was associated with normotension and a normal metabolic profile (canonical r = .50, chi2(36) = 59.1, P = .008). Hostility was related to elevated systolic blood pressure (SBP) and elevated triglycerides (TGs) (canonical r = .38, chi2(14) = 23.2, P = .052), whereas feelings of excessive tiredness were related to abdominal obesity, augmented glycemic responses to glucose ingestion, dyslipidemia, and increased PAI-1 antigen (canonical r = .39, chi2(24) = 36.8, P = .046). Although hostility and feelings of excessive tiredness have partly overlapping but clearly different clinical and metabolic correlates, their combination represents a full-blown IRS. Thus, even though insulin resistance is presumably to some extent genetically determined, these results suggest that considering psychosocial stress may be beneficial in understanding IRS risk-factor clustering.

Personality and Having Children: A Two-Way Relationship

Personality has been implicated in romantic and sexual relationships, but its association with childbearing is poorly understood. The authors assessed whether 3 personality traits--sociability, emotionality, and activity--predicted the probability of having children and whether having children predicted personality change. The participants were women and men from the Cardiovascular Risk in Young Finns study (N = 1,839) who were followed for 9 years. High emotionality decreased the probability of having children, whereas high sociability and, in men, high activity increased this probability. Having children predicted increasing emotionality, particularly in participants with high baseline emotionality and two or more children. In men, having children increased sociability in those with high baseline sociability and decreased sociability in those with low baseline sociability. These findings suggest a two-way relationship between personality and having children.

Comparison of Peer, Teacher and Self-Assessments on Adolescent Direct and Indirect Aggression

This study examined the relationships between peer, teacher and self-assessments on adolescent direct and indirect aggressive behaviour taking place at school. Subjects, a total of 2002, numbered 725 early, 575 middle and 702 late adolescent girls and boys. Measures on direct aggression included bullying, fighting and arguing, and measures on indirect aggression focused on backbiting and intriguing. The results revealed that, as a rule, the correlation between the peers and the teachers was higher than the agreement between the teachers and the self, which, in turn, was higher than that between the peers and the self. Consistency was also found to be higher with direct than with indirect aggression. Regarding age differences, the teacher-peer agreement was higher for the early and middle adolescents than for the late adolescents, while the teacher-self and the peer-self consistencies showed curvilinear relationships. Examining gender-related variance revealed that the peer-teacher correlation on direct aggression was higher for boys than for girls. No gender differences were found in assessments of indirect aggression. The results suggest, firstly, that self-ratings are not well interchangeable with peer or teacher assessments, which, in turn, are in line with each other, and, secondly, that there is a higher concordance in assessing direct than indirect aggression.

Association of Chronic Stress With Plasminogen Activator Inhibitor–1 in Healthy Middle-aged Men

The effect of chronic stress on tissue-type plasminogen activator (TPA) and plasminogen activator inhibitor-1 (PAI-1) antigens was studied in 69 healthy middle-aged men. Chronic stress, defined as feelings of fatigue, lack of energy, increased irritability, and demoralization, was positively associated with plasma concentrations of PAI-1 antigen but was unrelated to TPA. The association remained unaltered after controlling for age, smoking, alcohol consumption, and physical activity but became nonsignificant after further controlling for abdominal obesity, BMI, and serum insulin and triglyceride levels. This attenuated association implies that the relationship between vital exhaustion and PAI-1 may be secondary to the effects of the metabolic variables. Thus, the present study shows that long-term stress affects the fibrinolytic system and suggests that obesity and insulin and triglyceride concentrations, which are closely correlated with the fibrinolytic parameters, may mediate the association. These findings are consistent with the hypothesis that chronic stress causes increased synthesis of PAI-1, thus promoting the risk for atherothrombotic disease by decreasing the likelihood of spontaneous fibrinolysis and increasing the likelihood of fibrin deposition.

Job strain and early atherosclerosis: The cardiovascular risk in young Finns study

Objective: The purpose of this study was to determine whether job strain and social support are associated with early atherosclerosis measured by carotid intima-media thickness (IMT) in young adults. Methods: The subjects were 478 men and 542 women (mean age 32.3) who were participating in the ongoing prospective Cardiovascular Risk in Young Finns study. Job strain was defined as a joint effect of job demands and job control. Early atherosclerosis was determined with IMT ultrasound. The associations between job strain, social support, and IMT were evaluated using multiple linear regressions. Results: In men, job strain was associated with increased IMT after adjustment for age. This association was not attenuated by additional adjustment for established risk factors of coronary heart disease. In women, job strain was not associated with IMT. No 3-way interaction of job demand, job control, and social support on IMT was found. Conclusion: These findings suggest that job strain may be related to atherosclerosis already in its early nonsymptomatic stages in men. BMI = body mass index; CHD = coronary heart disease; CRYF = Cardiovascular Risk in Young Finns; HDL = high-density lipoprotein; IMT = intima-media thickness; LDL = low-density lipoprotein; OSQ = Occupational Stress Questionnaire; PAI = physical activity index; SES = socioeconomic status.

Maturity and change in personality: Developmental trends of temperament and character in adulthood

We studied the developmental trends of temperament and character in a longitudinal population-based sample of Finnish men and women aged 20-45 years using the Temperament and Character Inventory model of personality. Personality was assessed in 1997, 2001, and 2007 (n = 2,104, 2,095, and 2,056, respectively). Mean-level changes demonstrated qualitatively distinct developmental patterns for character (self-directedness, cooperativeness, and self-transcendence) and temperament (novelty seeking, harm avoidance, reward dependence, and persistence). Character developed toward greater maturity, although self-transcendence decreased with age. However, self-transcendence was the strongest predictor of overall personality change. Cohort effects indicated lower level of self-transcendence and higher level of self-directedness and cooperativeness in younger birth cohorts. Regarding temperament, novelty seeking decreased and persistence increased slightly with age. Both high novelty seeking and high persistence predicted overall personality change. These findings suggest that temperament and character traits follow different kinds of developmental trajectories.

Sleeping problems and health behaviors as mediators between organizational justice and health.

The aim of this longitudinal cohort study was to investigate whether sleeping problems and health behaviors (smoking, alcohol consumption, and sedentary lifestyle) mediate the association between organizational justice and employee health. Health indicators were minor psychiatric morbidity, as assessed by the General Health Questionnaire (U. Werneke, D. P. Goldberg, I. Yalcin, & B. T. Ustun, 2000), and poor self-rated health status. The results of logistic regression analysis of data for 416 male and 3,357 female hospital employees working during the 1998-2000 period in 10 Finnish hospitals suggest that sleeping problems are one of the underlying factors causing the adverse health effects of low organizational justice at work. No support for a mediating role of health behaviors between low organizational justice and health problems was obtained.

Early Socioeconomic Position and Blood Pressure in Childhood and Adulthood: The Cardiovascular Risk in Young Finns Study

Studies have found an association between low socioeconomic position in childhood and high adult blood pressure. It is unclear whether this association is explained by a pathway directly linking disadvantage to elevated blood pressure in childhood and adolescence, which then tracks into adulthood. We assessed parental socioeconomic position and systolic blood pressure in 1807 children and adolescents ages 3 to 18 years at baseline. Adult systolic blood pressure was measured 21 years later at ages 24 to 39 years. There was strong tracking of blood pressure from childhood to adulthood. Lower parental socioeconomic position was associated with higher blood pressure in childhood, adolescence (P<0.01), and adulthood (P<0.0001), with the mean age- and sex-adjusted systolic pressure differences between the highest and lowest socioeconomic groups varying between 2.9 and 4.3 mm Hg. With adjustment for blood pressure in childhood and adolescence, the regression coefficient between parental socioeconomic position and adult blood pressure attenuated by 32%. A similar level of attenuation (28%) occurred with adjustment for adult body mass index (BMI). With adjustment for both preadult blood pressure and adult BMI, the association between parental socioeconomic position and adult blood pressure was attenuated by 45%. Other factors, including birth weight and BMI in childhood and adolescence, had little impact on the association between parental socioeconomic position and adult blood pressure. These data suggest that early socioeconomic disadvantage influences later blood pressure in part through an effect on blood pressure in early life, which tracks into adulthood, and in part through an effect on BMI.