Abstract: BACKGROUND: Long-term illness and work incapacity in young adulthood has consequences for both the individual and for society. The purpose of the study was to investigate the association between adolescent health and receipt of long-term sickness and disability benefits for young adults in their twenties. MATERIAL AND METHOD: An adolescent population of 8949 school students (aged 13-21 years) assessed their own health in the Young-HUNT1 Study (1995-1997). Health was measured by means of a questionnaire enquiring about chronic somatic illnesses, somatic symptoms, symptoms of anxiety and depression, sleep disturbance, poor concentration, self-reported health and smoking, and by measuring height and weight. Information about receipt of long-term benefits was retrieved from the FD-Trygd registry for the period 1998-2008 and defined as receipt of sickness benefit (>180 days/year), medical/vocational rehabilitation benefit and disability pension in the age group 20-29 years. We investigated the relationship between adolescent health and long-term social insurance benefits with logistic regression, adjusted for sex, age, follow-up time, mother's education and family composition. Siblings with different exposure and outcome were investigated to adjust for all familial factors shared by siblings. RESULTS: Each of the health measures was associated with an increased risk of long-term benefit. For example, adolescents who reported one or more somatic illnesses or poor concentration had a 5.4 and 3.4 percentage point higher risk, respectively, of receiving long-term benefits at the age of 20-29 years than adolescents who did not report somatic illness or poor concentration. Moreover the risk increased with an increase in the number of health problems. Sibling analyses supported these associations. INTERPRETATION: Health in adolescence is an indicator of increased vulnerability in the transition to the labour market. Preventing health selection during this transition should be a priority for welfare policy.

Abstract: AIM: To compare depression in a sample of the medically hospitalized elderly with elderly people participating in a population-based health study in Norway and further to study the odds for depression, controlling for demographic and health differences between the two samples. METHOD: This cross-sectional observational study evaluated 484 medical inpatients from rural areas and 10,765 drawn from the Nord-Trondelag Health Study 3 (HUNT-3 Study) including participants from rural and urban areas. All participants were elderly (>/=65 years) with a mean (+/- standard deviation) age of 80.7 +/- 7.4 and 73.3 +/- 6.3 years, respectively. Symptoms of depression were screened by the Hospital Anxiety and Depression Scale (HAD). RESULTS: The prevalence of symptoms indicating mild, moderate or more severe depression (depression score >/=8) was about the same in both groups. In regression analyses, adjusting demographic and health differences, the odds for depression was lower for the elderly in the hospital sample than in the HUNT-3 Study. Older age, male gender, perceiving general health as poor, having impaired ability to function in daily life, previous consultation or treatment for emotional problems and anxiety (anxiety score >/=8) were associated with increased odds for depression in the elderly independent of being hospitalized or not. CONCLUSION: Surprisingly, we found the odds for depression after controlling for demographic and health variables to be lower in the hospitalized elderly individuals than in the elderly participating in the population-based health study. The health variables that were most strongly associated with an increased risk of depression were poor physical health and anxiety.

Abstract: BACKGROUND: Bias with regard to participation in epidemiological studies can have a large impact on the generalizability of results. Our aim was to investigate the direction and magnitude of potential bias by comparing health-related factors among participants and non-participants in a MRI-study based on HUNT, a large Norwegian health survey. METHODS: Of 14,033 individuals aged 50-65, who had participated in all three large public health surveys within the Norwegian county of Nord-Trondelag (HUNT 1, 2 and 3), 1,560 who lived within 45 minutes of travel from the city of Levanger were invited to a MRI study (MRI-HUNT). The sample of participants in MRI-HUNT (n = 1,006) were compared with those who were invited but did not participate (n = 554) and with those who were eligible but not invited (n = 12,473), using univariate analyses and logistic regression analyses adjusting for age and education level. RESULTS: Self-reported health did not differ between the three groups, but participants had a higher education level and were somewhat younger than the two other groups. In the adjusted multivariate analyses, obesity was consistently less prevalent among participants. Significant differences in blood pressure and cholesterol were also found. CONCLUSION: This is the first large population-based study comparing participants and non-participants in an MRI study with regard to general health. The groups were not widely different, but participants had a higher level of education, and were less likely to be obese and have hypertension, and were slightly younger than non-participants. The observed differences between participants and non-invited individuals are probably partly explained by the inclusion criterion that participants had to live within 45 minutes of transport to where the MRI examination took place. One will expect that the participants have somewhat less brain morphological changes related to cardiovascular risk factors than the general population. Such consequences underline the crucial importance of evaluation of non-participants in MRI studies.

Abstract: BACKGROUND: Endogenous estrogens prevent lipid peroxidation, which is pivotal in atherogenesis. Dyslipidemia may therefore be more dangerous for men than for women as a risk factor for acute myocardial infarction (AMI). A differential effect by sex has not been empirically established. METHODS: In a prospective population-based cohort study of 23,525 women and 20,725 men younger than 60 years of age at baseline, we followed participants for 12 years for a first AMI. By calculating the proportion of AMI among men with dyslipidemia attributable to the synergism between male sex and dyslipidemia, we assessed the degree to which dyslipidemia is more detrimental for men than for women. RESULTS: Dyslipidemia and male sex enhanced the effect of one another in relation to AMI risk. The proportion of AMI cases among men with dyslipidemia attributable to this synergism alone was 0.46 (95% confidence interval = 0.35 to 0.57) for high total serum cholesterol, 0.23 (0.05 to 0.41) for low high-density lipoprotein (HDL) cholesterol, and 0.52 (0.42 to 0.62) for high non-HDL cholesterol. In contrast, obesity and hypertension were equally detrimental for men and women in relation to AMI risk, with a corresponding attributable proportion of 0.02 (-0.21 to 0.25) and -0.01 (-0.27 to 0.24), respectively. CONCLUSIONS: Current clinical guidelines of dyslipidemia management do not distinguish between men and women in relation to primary prevention of AMI. Our results suggest that in middle age, dyslipidemia is much more detrimental for men than for women, and that preventing dyslipidemia has a greater potential to reduce the occurrence of AMI among men.

Abstract: AIMS: Norway is experiencing a rising life expectancy combined with an increasing dependency ratio – the ratio of those outside over those within the working force. To provide data relevant for future health policy we wanted to study trends in total and healthy life expectancy in a Norwegian population over three decades (1980s, 1990s and 2000s), both overall and across gender and educational groups. METHODS: Data were obtained from the HUNT Study, and the Norwegian Educational Database. We calculated total life expectancy and used the Sullivan method to calculate healthy life expectancies based on self-rated health and self-reported longstanding limiting illness. The change in health expectancies was decomposed into mortality and disability effects. RESULTS: During three consecutive decades we found an increase in life expectancy for 30-year-olds (~7 years) and expected lifetime in self-rated good health (~6 years), but time without longstanding limiting illness increased less (1.5 years). Women could expect to live longer than men, but the extra life years for females were spent in poor self-rated health and with longstanding limiting illness. Differences in total life expectancy between educational groups decreased, whereas differences in expected lifetime in self-rated good health and lifetime without longstanding limiting illness increased. CONCLUSIONS: The increase in total life expectancy was accompanied by an increasing number of years spent in good self-rated health but more years with longstanding limiting illness. This suggests increasing health care needs for people with chronic diseases, given an increasing number of elderly. Socioeconomic health inequalities remain a challenge for increasing pensioning age.