Abstract: Spouses tend to have similar lifestyles. We explored the degree to which spouse similarity in alcohol use, smoking, and physical exercise is caused by non-random mating or convergence. We used data collected for the Nord-Trondelag Health Study from 1984 to 1986 and prospective registry information about when and with whom people entered marriage/cohabitation between 1970 and 2000. Our sample included 19,599 married/cohabitating couples and 1,551 future couples that were to marry/cohabitate in the 14-16 years following data collection. All couples were grouped according to the duration between data collection and entering into marriage/cohabitation. Age-adjusted polychoric spouse correlations were used as the dependent variables in non-linear segmented regression analysis; the independent variable was time. The results indicate that spouse concordance in lifestyle is due to both non-random mating and convergence. Non-random mating appeared to be strongest for smoking. Convergence in alcohol use and smoking was evident during the period prior to marriage/cohabitation, whereas convergence in exercise was evident throughout life. Reduced spouse similarity in smoking with relationship duration may reflect secular trends.

Abstract: Few studies have investigated the association between serum 25-hydroxyvitamin D (25[OH]D), vitamin D supplement and asthma control among adults. We aimed to examine whether low levels of serum 25(OH)D or not taking vitamin D supplement were associated with an increased risk of poorly controlled asthma among Norwegian adults with asthma. We used a definition of asthma control adapted from the Global Initiative for Asthma. We first examined cross-sectional associations between serum 25(OH)D (n=806) or vitamin D supplement (n=1179) and poorly controlled asthma. Next, among those with well controlled asthma at baseline, we examined prospective associations between serum 25(OH)D (n=147) or vitamin D supplement (n=208) and poorly controlled asthma at follow-up, approximately 11 years later. We estimated risk ratios (RR) and 95% confidence intervals (CI) with Poisson regression. The adjusted RR for poorly controlled asthma was 1.00 (95% CI, 0.89-1.13) for adults with serum 25(OH)D<50nmol/L in cross-sectional and 1.50 (95% CI, 0.46-4.95) in prospective analyses. The adjusted RR for poorly controlled asthma was 1.17 (95% CI 1.00-1.37) for non-users of vitamin D supplement in cross-sectional and 1.66 (95% CI 0.49-5.67) in prospective analyses. Our study did not show strong evidence that among adults with asthma, having a low serum 25(OH)D or being a non-user of vitamin D supplement was associated with an increased risk of poorly controlled asthma. Some point estimates indicated an increased risk, however our estimates were generally imprecise and further evidence is needed.

Abstract: PURPOSE: The underlying goal of the study was to examine gender-specific effects of leisure-time physical activity on the development of symptoms of anxiety. METHODS: The second wave of a prospective cohort survey (HUNT 2) was conducted during 1995-1997 in the county of Nord-Trondelag, Norway, with a follow-up in 2006-2008 (HUNT 3). The sample consisted of 12,796 women and 11,195 men with an age range of 19-85 years. A binomial model with a log-link function and generalized linear model analysis with gamma distribution was used to assess the association between physical activity and anxiety symptoms (Hospital Anxiety and Depression Scale anxiety subscale, HADS-A). RESULTS: A total of 1,211 (9.5 %) women and 650 (5.8 %) men developed HADS-defined anxiety (>/=8 on the HADS-A scale). Men who scored in the middle tertile of the calculated physical activity index developed significantly fewer cases of HADS-defined anxiety compared with men in the lowest tertile (p

Abstract: BACKGROUND: School and work participation in adolescence and young adulthood are important for future health and socioeconomic status. The authors studied the association between self-rated health in adolescents, high school dropout and long-term receipt of medical and non-medical social insurance benefits in young adulthood. METHODS: Self-rated health in adolescence was assessed in 8795 adolescents participating in the Norwegian Young-HUNT Study (1995-1997). Linkages to the National Education Database and the National Insurance Administration allowed identification of school dropout and receipt of long-term medical and non-medical benefits during a 10-year follow-up (1998-2007). The data were explored by descriptive statistics and by multinomial logistic regression. RESULTS: A total of 17% was registered as being high school dropouts at age 24. The predicted 5-year risk of receiving benefits between ages 24-28 was 21% (95% CI 20% to 23%). High school dropouts had a 5-year risk of receiving benefits of 44% (95% CI 41 to 48) compared with 16% (95% CI 15 to 17) in those who completed high school (adjusted for self-rated health, parental education and sex). There was a 27% school dropout rate in adolescents who reported poor health compared with 16% in those who reported good health. The predicted 5-year risk of receiving any long-term social insurance benefits in adolescents who reported poor health was 33% (95% CI 30 to 37) compared with 20% (95% CI 19 to 21) in those who reported good health. CONCLUSION: The strong association between poor self-rated health in adolescence, high school dropout and reduced work integration needs attention and suggests preventive measures on an individual as well as on a societal level.

Abstract: PURPOSE: To study if physical activity within the recommended level over time was associated with risk of developing depression after the first myocardial infarction in older adults. METHODS: Men (n = 143) and women (n = 46) who had reached the age of 60 years in 2006-2008 who participated in the Nord-Trondelag Health Study (HUNT1, 1984-1986; HUNT2, 1995-1997; HUNT3, 2006-2008) without any mental illness or cardiovascular disease at baseline in HUNT2 and who experienced their first myocardial infarction before HUNT3 were included. Based on the patterns of physical activity from HUNT1 to HUNT2, the sample was divided into 4 groups: persistently inactive, from active to inactive, from inactive to active, and persistently active. The primary outcome, post-myocardial infarction depression symptoms, was measured with the Hospital, Anxiety and Depression Scale in HUNT3. RESULTS: In HUNT3, 11% of participants had depression. After multivariable adjustment, those who were persistently active had significantly lower odds of being depressed (odds ratio 0.28; 95% confidence interval, 0.08-0.98) compared with those who were persistently inactive. Additionally, a significant test for trend (P = .033) of lowering odds of depression was observed across all 4 categories of physical activity patterns at baseline. CONCLUSIONS: In this small sample of initially healthy adults, we observed a long-term protective effect of regular physical activity on the development of depression following myocardial infarction.

Abstract: Background: Circulating concentrations of B vitamins and factors related to one-carbon metabolism have been found to be strongly inversely associated with lung cancer risk in the European Prospective Investigation into Cancer and Nutrition (EPIC) study. The extent to which these associations are present in other study populations is unknown. Methods: Within 20 prospective cohorts from the National Cancer Institute Cohort Consortium, a nested case-control study was designed including 5364 incident lung cancer case patients and 5364 control subjects who were individually matched to case patients by age, sex, cohort, and smoking status. Centralized biochemical analyses were performed to measure circulating concentrations of vitamin B6, folate, and methionine, as well as cotinine as an indicator of recent tobacco exposure. The association between these biomarkers and lung cancer risk was evaluated using conditional logistic regression models. Results: Participants with higher circulating concentrations of vitamin B6 and folate had a modestly decreased risk of lung cancer risk overall, the odds ratios when comparing the top and bottom fourths (OR 4vs1 ) being 0.88 (95% confidence interval [CI] = 0.78 to 1.00) and 0.86 (95% CI = 0.74 to 0.99), respectively. We found stronger associations among men (vitamin B6: OR 4vs1 = 0.74, 95% CI = 0.62 to 0.89; folate: OR 4vs1 = 0.75, 95% CI = 0.61 to 0.93) and ever smokers (vitamin B6: OR 4vs1 = 0.78, 95% CI = 0.67 to 0.91; folate: OR 4vs1 = 0.87, 95% CI = 0.73 to 1.03). We further noted that the association of folate was restricted to Europe/Australia and Asia, whereas no clear association was observed for the United States. Circulating concentrations of methionine were not associated with lung cancer risk overall or in important subgroups. Conclusions: Although confounding by tobacco exposure or reverse causation cannot be ruled out, these study results are compatible with a small decrease in lung cancer risk in ever smokers who avoid low concentrations of circulating folate and vitamin B6.

Abstract: In previous studies on prescription patterns of opioids, accurate data on pain are missing, and previous epidemiological studies of pain lack accurate data on opioid use. The present linkage study, which investigates the relationship between pain and opioid use, is based on accurate individual data from the complete national Norwegian prescription database and the Nord-Trondelag health study 3, which includes about 46,000 people. Baseline data were collected in 2006 to 2008, and the cohort was followed up for 3 years. Of 14,477 people who reported chronic nonmalignant pain, 85% did not use opioids at all, 3% used opioids persistently, and 12% used opioids occasionally. Even in the group reporting severe or very severe chronic pain, the number not using opioids (2680) was far higher than the number who used opioids persistently (304). However, three quarters of people using opioids persistently reported strong or very strong pain in spite of the medication. Risk factors for the people with chronic pain who were not persistent opioid users at baseline to use opioids persistently 3 years later were occasional use of opioids, prescription of >100 defined daily doses per year of benzodiazepines, physical inactivity, reports of strong pain intensity, and prescription of drugs from 8 or more Anatomical Therapeutic Chemical groups. The study showed that most people having chronic nonmalignant pain are not using opioids, even if the pain is strong or very strong. However, the vast majority of patients with persistent opioid use report strong or very strong pain in spite of opioid treatment.

Abstract: BACKGROUND: Current evidence concerning sedentary behaviour and mortality risk has used single time point assessments of sitting. Little is known about how changes in sitting levels over time affect subsequent mortality risk. AIM: To examine the associations between patterns of sitting time assessed at two time points 11 years apart and risk of all-cause and cardio-metabolic disease mortality. METHODS: Participants were 25,651 adults aged > =20 years old from the Nord-Trondelag Health Study with self-reported total sitting time in 1995-1997 (HUNT2) and 2006-2008 (HUNT3). Four categories characterised patterns of sitting: (1) low at HUNT2/ low at HUNT3, 'consistently low sitting'; (2) low at HUNT2/high at HUNT3, 'increased sitting'; (3) high at HUNT2/low at HUNT3, 'reduced sitting'; and (4) high at HUNT2 /high at HUNT3, 'consistently high sitting'. Associations of sitting pattern with all-cause and cardio-metabolic disease mortality were analysed using Cox regression adjusted for confounders. RESULTS: Mean follow-up was 6.2 years (158880 person-years); 1212 participants died. Compared to 'consistently low sitting', adjusted hazard ratios for all-cause mortality were 1.51 (95% CI: 1.28-2.78), 1.03 (95% CI: 0.88-1.20), and 1.26 (95% CI: 1.06-1.51) for 'increased sitting', 'reduced sitting' and 'consistently high sitting' respectively. CONCLUSIONS: Examining patterns of sitting over time augments single time-point analyses of risk exposures associated with high sitting time. Whilst sitting habits can be stable over a long period, life events (e.g., changing jobs, retiring or illness) may influence sitting trajectories and therefore sitting-attributable risk. Reducing sitting may yield mortality risks comparable to a stable low-sitting pattern.

Abstract: BACKGROUND: Young people's alcohol consumption is related to their parents' alcohol consumption, but little focus has been placed on whether there is a connection with parental intoxication. The purpose of the study was to investigate whether the experience of seeing their parents intoxicated is associated with young people's alcohol consumption and experimenting with drugs in their teens. MATERIAL AND METHOD: The study is prospective and based on data from 2,399 teenagers who took part in the Ung-HUNT 1 study in 1995-1997 and the Ung-HUNT 2 study in 2000-2001. Self-reported questionnaire data and analysis by means of logistic regression, stratified by gender, were used. RESULTS: Having been drunk > 10 times was associated with having seen their parents intoxicated among boys (OR 3.7; 95% CI 2.7-5.1 and girls (OR 2.0; 1.5-2.6). Drinking alcohol weekly or more frequently was associated with parental intoxication among boys (OR 2.2; 1.6-3.0), but not girls unless they had seen their parents drunk many times (OR 2.4; 1.1-5.2). Experimenting with drugs was associated with parental intoxication among both boys (OR 2.6; 1.7-3.9) and girls (OR 1.6; 1.1-2.2). INTERPRETATION: Repeated intoxication, frequent alcohol consumption and experimenting with drugs by teenagers were associated with seeing their parents intoxicated. There are other explanatory factors for which the study was unable to control, and interpretation of the results should take this into account.

Abstract: STUDY DESIGN: A population-based, prospective cohort study. OBJECTIVE: To determine whether overweight, obesity, or more generally an elevated body mass index (BMI) increase the probability of experiencing chronic low back pain (LBP) after an 11-year period, both among participants with and without LBP at baseline. SUMMARY OF BACKGROUND DATA: Chronic LBP is a common disabling disorder in modern society. Cross-sectional studies suggest an association between an elevated BMI and LBP, but it is not clear whether this is a causal relationship. METHODS: Data were obtained from the community-based HUNT 2 (1995-1997) and HUNT 3 (2006-2008) studies of an entire Norwegian county. Participants were 8733 men and 10,149 women, aged 30 to 69 years, who did not have chronic LBP at baseline, and 2669 men and 3899 women with LBP at baseline. After 11 years, both groups indicated whether they currently had chronic LBP, defined as pain persisting for at least 3 months continuously during the last year. RESULTS: A significant positive association was found between BMI and risk of LBP among persons without LBP at baseline. The odds ratio for BMI 30 or more versus BMI less than 25 was 1.34 (95% confidence interval [CI], 1.08-1.67) for men and 1.22 (95% CI, 1.03-1.46) for women, in analyses adjusted for age, education, work status, physical activity at work and in leisure time, smoking, blood pressure, and serum lipid levels. A significant positive association was also established between BMI and recurrence of LBP among women. LBP status at baseline had negligible influence on subsequent change in BMI. CONCLUSION: High values of BMI may predispose to chronic LBP 11 years later, both in individuals with and without LBP. The association between BMI and LBP is not explained by an effect of LBP on later change in BMI.

Abstract: AIMS/HYPOTHESIS: Excessive weight is a risk factor for type 2 diabetes, but its role in the promotion of autoimmune diabetes is not clear. We investigated the risk of latent autoimmune diabetes in adults (LADA) in relation to overweight/obesity in two large population-based studies. METHODS: Analyses were based on incident cases of LADA (n = 425) and type 2 diabetes (n = 1420), and 1704 randomly selected control participants from a Swedish case-control study and prospective data from the Norwegian HUNT Study including 147 people with LADA and 1,012,957 person-years of follow-up (1984-2008). We present adjusted ORs and HRs with 95% CI. RESULTS: In the Swedish data, obesity was associated with an increased risk of LADA (OR 2.93, 95% CI 2.17, 3.97), which was even stronger for type 2 diabetes (OR 18.88, 95% CI 14.29, 24.94). The association was stronger in LADA with low GAD antibody (GADA; <median) (OR 4.25; 95% CI 2.76, 6.52) but present also in LADA with high GADA (OR 2.14; 95% CI 1.42, 3.24). In the Swedish data, obese vs normal weight LADA patients had lower GADA levels, better beta cell function, and were more likely to have low-risk HLA-genotypes. The combination of overweight and family history of diabetes (FHD) conferred an OR of 4.57 (95% CI 3.27, 6.39) for LADA and 24.51 (95% CI 17.82, 33.71) for type 2 diabetes. Prospective data from HUNT indicated even stronger associations; HR for LADA was 6.07 (95% CI 3.76, 9.78) for obesity and 7.45 (95% CI 4.02, 13.82) for overweight and FHD. CONCLUSIONS/INTERPRETATION: Overweight/obesity is associated with increased risk of LADA, particularly when in combination with FHD. These findings support the hypothesis that, even in the presence of autoimmunity, factors linked to insulin resistance, such as excessive weight, could promote onset of diabetes.

Abstract: BACKGROUND: Studies have shown an independent association between poor self-rated health (SRH) and increased mortality. Few studies, however, have investigated any possible impact on SRH of diagnostic labelling. OBJECTIVE: To test whether SRH differed in persons with known and unknown hypothyroidism, diabetes mellitus (DM) or hypertension, opposed to persons without these conditions, after 11-year follow-up. METHODS: Prospective population-based cohort study in North-Trondelag County, Norway, HUNT2 (1995-97) to HUNT3 (2006-08). All inhabitants aged 20 years and older were invited. The response rate was 69.5% in HUNT2 and 54.1% in HUNT3. In total, 34144 persons aged 20-70 years were included in the study population. The outcome was poor SRH. RESULTS: Persons with known disease had an increased odds ratio (OR) to report poor SRH at follow-up; figures ranging from 1.11 (0.68-1.79) to 2.52 (1.46-4.34) (men with hypothyroidism kept out owing to too few numbers). However, in persons not reporting, but having laboratory results indicating these diseases (unknown disease), no corresponding associations with SRH were found. Contrary, the OR for poor SRH in women with unknown hypothyroidism and unknown hypertension was 0.64 (0.38-1.06) and 0.89 (0.79-1.01), respectively. CONCLUSIONS: Awareness opposed to ignorance of hypothyroidism, DM and hypertension seemed to be associated with poor perceived health, suggesting that diagnostic labelling could have a negative effect on SRH. This relationship needs to be tested more thoroughly in future research but should be kept in mind regarding the benefits of early diagnosing of diseases.