Psychosocial factors, health behaviors and risk of cancer incidence: Testing interaction and effect modification in an individual participant data meta-analysis.

Depression, anxiety and other psychosocial factors are hypothesized to be involved in cancer development. We examined whether psychosocial factors interact with or modify the effects of health behaviors, such as smoking and alcohol use, in relation to cancer incidence. Two-stage individual participant data meta-analyses were performed based on 22 cohorts of the PSYchosocial factors and CAncer (PSY-CA) study. We examined nine psychosocial factors (depression diagnosis, depression symptoms, anxiety diagnosis, anxiety symptoms, perceived social support, loss events, general distress, neuroticism, relationship status), seven health behaviors/behavior-related factors (smoking, alcohol use, physical activity, body mass index, sedentary behavior, sleep quality, sleep duration) and seven cancer outcomes (overall cancer, smoking-related, alcohol-related, breast, lung, prostate, colorectal). Effects of the psychosocial factor, health behavior and their product term on cancer incidence were estimated using Cox regression. We pooled cohort-specific estimates using multivariate random-effects meta-analyses. Additive and multiplicative interaction/effect modification was examined. This study involved 437,827 participants, 36,961 incident cancer diagnoses, and 4,749,481 person years of follow-up. Out of 744 combinations of psychosocial factors, health behaviors, and cancer outcomes, we found no evidence of interaction. Effect modification was found for some combinations, but there were no clear patterns for any particular factors or outcomes involved. In this first large study to systematically examine potential interaction and effect modification, we found no evidence for psychosocial factors to interact with or modify health behaviors in relation to cancer incidence. The behavioral risk profile for cancer incidence is similar in people with and without psychosocial stress.

Estimating Additive Interaction in Two-Stage Individual Participant Data Meta-Analysis.

Individual participant data (IPD) meta-analysis provides important opportunities to study interaction and effect modification for which individual studies often lack power. While previous meta-analyses have commonly focused on multiplicative interaction, additive interaction holds greater relevance for public health and may in certain contexts better reflect biological interaction. Methodological literature on interaction in IPD meta-analysis does not cover additive interaction for models including binary or time-to-event outcomes. We aimed to describe how the Relative Excess Risk due to Interaction (RERI) and other measures of additive interaction or effect modification can be validly estimated within two-stage IPD meta-analysis. First, we explain why direct pooling of study-level RERI estimates may lead to invalid results. Next, we propose a three-step procedure to estimate additive interaction: 1) estimate effects of both exposures and their product term on the outcome within each individual study; 2) pool study-specific estimates using multivariate meta-analysis; 3) estimate an overall RERI and 95% confidence interval based on the pooled effect estimates. We illustrate this procedure by investigating interaction between depression and smoking and risk of smoking-related cancers using data from the PSYchosocial factors and Cancer (PSY-CA) consortium. We discuss implications of this procedure, including the application in meta-analysis based on published data.

The mediating role of health behaviors in the association between depression, anxiety and cancer incidence: an individual participant data meta-analysis.

BACKGROUND: Although behavioral mechanisms in the association among depression, anxiety, and cancer are plausible, few studies have empirically studied mediation by health behaviors. We aimed to examine the mediating role of several health behaviors in the associations among depression, anxiety, and the incidence of various cancer types (overall, breast, prostate, lung, colorectal, smoking-related, and alcohol-related cancers). METHODS: Two-stage individual participant data meta-analyses were performed based on 18 cohorts within the Psychosocial Factors and Cancer Incidence consortium that had a measure of depression or anxiety (N = 319 613, cancer incidence = 25 803). Health behaviors included smoking, physical inactivity, alcohol use, body mass index (BMI), sedentary behavior, and sleep duration and quality. In stage one, path-specific regression estimates were obtained in each cohort. In stage two, cohort-specific estimates were pooled using random-effects multivariate meta-analysis, and natural indirect effects (i.e. mediating effects) were calculated as hazard ratios (HRs). RESULTS: Smoking (HRs range 1.04-1.10) and physical inactivity (HRs range 1.01-1.02) significantly mediated the associations among depression, anxiety, and lung cancer. Smoking was also a mediator for smoking-related cancers (HRs range 1.03-1.06). There was mediation by health behaviors, especially smoking, physical inactivity, alcohol use, and a higher BMI, in the associations among depression, anxiety, and overall cancer or other types of cancer, but effects were small (HRs generally below 1.01). CONCLUSIONS: Smoking constitutes a mediating pathway linking depression and anxiety to lung cancer and smoking-related cancers. Our findings underline the importance of smoking cessation interventions for persons with depression or anxiety.

Trends in Norwegian adolescents' substance use between 2014 and 2022: socioeconomic and gender differences.

BACKGROUND: Substance use is a global health concern and early onset among adolescents increases health risks. We explore national overall trends in prevalence and trends in socioeconomic inequalities in past year alcohol intoxication, cannabis use, and use of other illicit drugs among Norwegian adolescents (ages ∼ 15-19 years of age) between 2014 and 2022. METHOD: The present study builds on data from a nationwide repeated cross-sectional survey collected in 2014-2016 (T1), 2017-2019 (T2), 2021 (T3) and 2022 (T4). In total 415,560 adolescents (50.3% girls) completed the questionnaire during the study period. Trends in socioeconomic inequalities were assessed using the Slope Index of Inequality (SII) and the Relative Index of Inequality (RII). RESULTS: While the prevalence of alcohol intoxication remained fairly stable, the prevalence of cannabis and other illicit drug use increased between 2014 and 2022 among upper secondary school boys (13.3-17.6%, and 2.0-5.2%, respectively) and girls (8.8-12.8%, and 1.1-2.7%, respectively). Similar trends were observed among 10th-grade adolescents. Boys were more likely than girls to use cannabis or other illicit drugs, but the gender gap in cannabis use narrowed during the study period. Among upper secondary girls, use of cannabis and other illicit drugs was higher among those from less affluent backgrounds, with absolute and relative inequalities in cannabis use increasing between 2014 and 2022. Small inequalities in cannabis use and decreasing relative inequalities in the use of other illicit drug were observed among upper secondary boys. CONCLUSIONS: The increasing use of cannabis and other illicit drugs among Norwegian adolescents is concerning. Future studies should explore the underlying causes of this rise and explore the complex factors influencing adolescent substance use behaviours. A comprehensive understanding of these factors is essential for developing targeted and effective interventions.

School completion and progression to higher education in adolescents with social anxiety: a linkage between Young-HUNT3 and national educational data (2008-2019), Norway.

BACKGROUND: Social anxiety disorder (SAD) most commonly develops in adolescence-a period of life that includes a transition to upper secondary school. The aim of this study is to investigate the extent to which social anxiety in adolescence is associated with the completion of upper secondary school and progression to higher education. METHODS: This longitudinal study includes 8,192 adolescents aged 13-19 years who participated in the Norwegian Young-HUNT 3 population-based study. Social anxiety is measured employing (1) diagnostic interview screening questions (interview) and (2) a self-reported symptom index (questionnaire). Notably, we define the cohorts based on these two methods. Using national educational data (2008-2019), we follow educational attainment among the cohorts until they turn 25 years of age. RESULTS: We found that adolescents who screened positive (SP) for SAD had a predicted probability of upper secondary school completion at 21 years of age that was 14% points lower than those who screened negative (SN). Further, differences remained when looking at completion rates at age 25 years. Moreover, predicted probabilities for completion were inversely associated with increasing levels of self-reported social anxiety symptoms. Similarly, the proportion of the completers of an academic program in the SP group that were enrolled in higher education by 25 years of age, were lower than for the SN group (87 vs. 92%). CONCLUSION: Social anxiety in adolescence, both self-reported symptoms and diagnostic screening, has long-term negative impact on upper secondary school completion and to some extent enrollment to higher education.

Trends in socioeconomic inequalities in self-rated health and mental distress during four decades in a Norwegian population: a HUNT Study.

BACKGROUND: Socioeconomic inequalities constitute an important focus area for public health, and it has long been established that higher educational level and longer lifespan are correlated. Little is known about decennial time trends in poor self-rated health and mental distress. METHODS: This study linked decennial cross-sectional survey data on self-rated health and mental distress from the Trøndelag Health Study (HUNT) from 1984 to 2019 with educational registry data using personal identification numbers. Survey participation ranged from 50 807 to 77 212. Slope index of inequality (SII) and relative index of inequality (RII) were calculated using generalized linear models in Stata. Analyses were stratified by sex and age, using the age categories of 30-59 years and 60-80 years. RESULTS: Absolute inequalities in self-rated health and mental distress between educational groups have stayed relatively stable throughout all rounds of HUNT. Relative inequalities in self-rated health and mental distress have generally increased, and both men and women with the lowest education level were more likely to experience poor self-rated health and mental distress relative to those with the highest education level. RII in self-rated health increased over time for both sexes and both age groups. RII for mental distress increased in both sexes and both age groups, except for men and women aged 60-80. DISCUSSION: This study shows that relative inequalities in self-rated and mental health in the Norwegian population are still persistent and have increased. Further knowledge about groups with a disadvantageous health situation should have implications for health care resource allocation.

Depression, anxiety, and the risk of cancer: An individual participant data meta-analysis.

BACKGROUND: Depression and anxiety have long been hypothesized to be related to an increased cancer risk. Despite the great amount of research that has been conducted, findings are inconclusive. To provide a stronger basis for addressing the associations between depression, anxiety, and the incidence of various cancer types (overall, breast, lung, prostate, colorectal, alcohol-related, and smoking-related cancers), individual participant data (IPD) meta-analyses were performed within the Psychosocial Factors and Cancer Incidence (PSY-CA) consortium. METHODS: The PSY-CA consortium includes data from 18 cohorts with measures of depression or anxiety (up to N = 319,613; cancer incidences, 25,803; person-years of follow-up, 3,254,714). Both symptoms and a diagnosis of depression and anxiety were examined as predictors of future cancer risk. Two-stage IPD meta-analyses were run, first by using Cox regression models in each cohort (stage 1), and then by aggregating the results in random-effects meta-analyses (stage 2). RESULTS: No associations were found between depression or anxiety and overall, breast, prostate, colorectal, and alcohol-related cancers. Depression and anxiety (symptoms and diagnoses) were associated with the incidence of lung cancer and smoking-related cancers (hazard ratios [HRs], 1.06-1.60). However, these associations were substantially attenuated when additionally adjusting for known risk factors including smoking, alcohol use, and body mass index (HRs, 1.04-1.23). CONCLUSIONS: Depression and anxiety are not related to increased risk for most cancer outcomes, except for lung and smoking-related cancers. This study shows that key covariates are likely to explain the relationship between depression, anxiety, and lung and smoking-related cancers. PREREGISTRATION NUMBER: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=157677.

Trends in social inequality and how mental wellbeing vary and covary among Norwegian adolescents and their families: the Young-HUNT Study.

BACKGROUND: The study had two aims: first, to investigate trends in socioeconomic inequalities in psychological distress and loneliness among Norwegian adolescents, and second, to study variation and covariation of psychological distress and loneliness within adolescents and between siblings within families. METHODS: Multivariate mixed models were used to investigate trends in socioeconomic inequality in psychological distress and loneliness using three separate cohorts of Norwegian adolescents from the Young-HUNT study conducted in 1995-1997 (Young-HUNT1, n = 8980), 2006-2008 (Young-HUNT3, n = 8199) and 2017-2019 (Young-HUNT4, n = 8066). Register data on parental education level was used as a marker of socioeconomic position (SEP), and a unique family number was used to identify adolescents belonging to the same family. A three-level multivariate mixed model was created, consisting of the outcomes at level 1, adolescents at level 2 and families at level 3. RESULTS: No statistically significant difference in scores on loneliness and psychological distress was observed between low and high parental education level in Young-HUNT1, whereas in Young-HUNT4, low parental education level was associated with a higher score on both psychological distress (ß = 0.09; 95% confidence interval (CI), 0.03-0.14) and loneliness (ß = 0.12; 95% CI 0.07-0.17). Analyses of covariation between psychological distress and loneliness showed that they were correlated within adolescents and strongly correlated within families across all timepoints. CONCLUSIONS: Increasing socioeconomic inequalities in psychological distress and loneliness among Norwegian adolescents is worrisome. Further, the family seems to be an important arena for potential prevention of psychological distress and loneliness among adolescents, regardless of parental education level.

National health registries - a 'goldmine' for studying non-communicable disease occurrence in Norway - the NCDNOR project.

To estimate occurrence of non-communicable diseases (NCDs) over the life-course in the Norwegian population, national health registries are a vital source of information since they fully represent the entire non-institutionalised population. However, as they are mainly established for administrative purposes, more knowledge about how NCDs are recorded in the registries is needed. To establish this, we begin by counting the number of individuals registered annually with one or more NCDs in any of the registries. The study population includes all inhabitants who lived in Norway from 2004 to 2020 (N~6.4m). The NCD outcomes are diabetes, cardiovascular diseases, chronic obstructive lung diseases, cancer and mental disorders/substance use disorders. Further, we included hip fractures in our NCD concept. The data sources used to identify individuals with NCDs, including detailed information on diagnoses in primary and secondary health care and dispensings of prescription drugs, are the Cancer Registry of Norway, The Norwegian Patient Registry, The Norwegian Control and Payment of Health Reimbursement database, and The Norwegian Prescription Database. The number of individuals registered annually with an NCD diagnosis and/or a dispensed NCD drug increased over the study period. Changes over time may reflect changes in disease incidence and prevalence, but also changes in disease-specific guidelines, reimbursement schemes and access to and use of health services. Data from more than one health registry to identify individuals with NCDs are needed since the registries reflect different levels of health care services and therefore may reflect disease severity.

Trends in the use of home care services among Norwegians 70+ and projections towards 2050: The HUNT study 1995-2017.

BACKGROUND: Life expectancy (LE) is increasing worldwide, while there is lack of information on how this affects older individuals' use of formal home care services. AIM: We aimed to decompose LE into years with and without home care services and estimate projected number of users towards 2050 in Norway for people 70 years or older. METHODS: This study is based on a sample of 25,536 participants aged 70 years and older in the Trøndelag Health Study (HUNT) survey 2 (1995-1997), 3 (2006-2008), or 4 (2017-2019) linked with national data on mortality. Prevalence of home care services was standardised to the Norwegian population by age and sex. The Sullivan method was used to estimate expected years with and without home help services and nursing services for the years 1995, 2006 and 2016. Data from HUNT4 and Statistics Norway were used to estimate projected use of these services between 2020 and 2050. RESULTS: During 1995-2017, the use of home help services decreased from 22.6% to 6.2% (p < 0.001), and from 6.4% to 5.5% (p = 0.004) for home nursing services. Adjusted for age and sex, the use of home help services decreased significantly over time (p < 0.001), while home nursing services were stable (p = 0.69). LE at age 70 increased from 11.9 to 15.3 years in men (p < 0.05) during 1995-2017, and from 14.7 to 17.1 in women (p < 0.05). In the same period, the expected years receiving home help decreased from 2.6 to 1.1 in men (p < 0.05), and from 4.4 to 2.1 in women (p < 0.05). The expected years receiving home nursing increased from 0.6 to 0.9 in men (p < 0.05), and from 1.3 to 1.7 in women (p < 0.05). Projected numbers of people 70+ in Norway in need of either of these services were estimated to rise from 64,000 in 2020 to 160,000 in 2050. CONCLUSION: While overall life expectancy increased, the expected years receiving home help have decreased and home nursing slightly increased among the Norwegian population aged 70 years and older during 1995-2017. However, the substantial increase in the projected number of older adults using home care services in the future is an alert for the current health care planners.

HUNT for better public health.

AIMS: The Trøndelag Health Study (HUNT) has collected population data through comprehensive decennial surveys over the last four decades and has so far collected data from 240,000 participants. The participants are identified with the unique Norwegian birth number, which enables them to be followed throughout different life stages, from survey to survey, and to endpoint measures in Norwegian national health registers without attrition bias. METHODS: The study design of HUNT offers several advantages: it provides an overview of the public health development in the population over decades, the data can be used in health services research, clinical epidemiology, studies of causation, trajectories, and consequences of diseases, and to study gene × environment interactions. RESULTS: HUNT data have shown major shifts in public health trends, such as decreasing mean blood pressure and resting heart rate among adults, increasing prevalence of obesity, geographical and socioeconomic inequalities in health, increasing mental health distress among adolescents and young adults with an opposite development among the elderly. Data from HUNT have been used in several major international research projects, where data harmonization with several other population cohorts internationally has been done. HUNT has placed great emphasis on safeguarding research ethics, privacy, and data security. The Norwegian authorities established national regulations for the surveys from the time General Data Protection Regulation was introduced in 2018. CONCLUSIONS: Researchers can apply for HUNT data access from HUNT Research Centre provided they have obtained project approval from the Regional Committee for Medical and Health Research Ethics. Researchers not affiliated to a Norwegian research institution must collaborate with and apply through a Norwegian principal investigator. Information on the application and conditions for data access is available at www.ntnu.edu/hunt/data.

Trends in Disability-Free Life Expectancy (DFLE) from 1995 to 2017 in the older Norwegian population by sex and education: The HUNT Study.

AIM: Understanding whether increasing Life Expectancy (LE) translates to improved health and function among older adults is essential, but results are inconclusive. We aimed to estimate trends in Disability-Free Life Expectancy (DFLE) in the older Norwegian population by sex and education from 1995 to 2017. METHOD: National life table data were combined with cross-sectional data on functional ability for 70+ year-olds from the population-based Trøndelag Health Surveys 2-4 (1995-1997, 2006-2008 and 2017-2019) (n=24,733). Self-reported functional ability was assessed on a graded scale by a combination of Instrumental Activities of Daily Living (IADL) such as paying bills, going out or shopping (mild disability) and Personal Activities of Daily Living (PADL) such as washing, dressing or eating (severe disability). LE, DFLE, Mild-Disability LE and Severe-Disability LE at age 70 were estimated by the Sullivan method. RESULTS: From 1995 to 2017 DFLE at age 70 increased from 8.4 to 13.0 years in women, and from 8.0 to 12.1 years in men. DFLE increased in the basic and high educational groups, but more so in the high educational group among men. Educational inequalities in years spent with disability however, remained low. CONCLUSIONS: From the mid-1990s and over the past three decades both LE and DFLE at 70 years increased in the older Norwegian population, for both men and women, and across basic and high educational levels. Educational inequalities in DFLE increased, especially in men, but years spent with disability were similar across the three decades.

Developmental Course and Risk Factors of Physical Aggression in Late Adolescence.

This study examined risk factors of physical aggression during transition from early to late adolescence using a two-wave longitudinal study. Specifically, we examined if risk factors in early adolescence predict physically aggressive behavior starting in late adolescence and why some adolescents desist physical aggressive behavior while others do not. The study sample consisted of 2289 Norwegian adolescents (1235 girls) who participated in the Young-HUNT1 study (mean age 14.5) and the follow-up study 4 years later, Young-HUNT2 study (mean age 18.4). One in six young adolescents reported engaging in physical fights. Moreover, physical aggression in early adolescence was significantly associated with male gender, attention problems, academic problems, being bullied, drinking alcohol, and smoking. Male gender and heavy drinking during early adolescence increased the risk for newly emerging aggressive behavior in late adolescence, whereas heavy drinking during early adolescence was a predictor for persistent versus desisting aggressive behavior in late adolescence.

Genetic associations with temporal shifts in obesity and severe obesity during the obesity epidemic in Norway: A longitudinal population-based cohort (the HUNT Study).

BACKGROUND: Obesity has tripled worldwide since 1975 as environments are becoming more obesogenic. Our study investigates how changes in population weight and obesity over time are associated with genetic predisposition in the context of an obesogenic environment over 6 decades and examines the robustness of the findings using sibling design. METHODS AND FINDINGS: A total of 67,110 individuals aged 13-80 years in the Nord-Trøndelag region of Norway participated with repeated standardized body mass index (BMI) measurements from 1966 to 2019 and were genotyped in a longitudinal population-based health study, the Trøndelag Health Study (the HUNT Study). Genotyping required survival to and participation in the HUNT Study in the 1990s or 2000s. Linear mixed models with observations nested within individuals were used to model the association between a genome-wide polygenic score (GPS) for BMI and BMI, while generalized estimating equations were used for obesity (BMI ≥ 30 kg/m2) and severe obesity (BMI ≥ 35 kg/m2). The increase in the average BMI and prevalence of obesity was steeper among the genetically predisposed. Among 35-year-old men, the prevalence of obesity for the least predisposed tenth increased from 0.9% (95% confidence interval [CI] 0.6% to 1.2%) to 6.5% (95% CI 5.0% to 8.0%), while the most predisposed tenth increased from 14.2% (95% CI 12.6% to 15.7%) to 39.6% (95% CI 36.1% to 43.0%). Equivalently for women of the same age, the prevalence of obesity for the least predisposed tenth increased from 1.1% (95% CI 0.7% to1.5%) to 7.6% (95% CI 6.0% to 9.2%), while the most predisposed tenth increased from 15.4% (95% CI 13.7% to 17.2%) to 42.0% (95% CI 38.7% to 45.4%). Thus, for 35-year-old men and women, respectively, the absolute change in the prevalence of obesity from 1966 to 2019 was 19.8 percentage points (95% CI 16.2 to 23.5, p < 0.0001) and 20.0 percentage points (95% CI 16.4 to 23.7, p < 0.0001) greater for the most predisposed tenth compared with the least predisposed tenth, defined using the GPS for BMI. The corresponding absolute changes in the prevalence of severe obesity for men and women, respectively, were 8.5 percentage points (95% CI 6.3 to 10.7, p < 0.0001) and 12.6 percentage points (95% CI 9.6 to 15.6, p < 0.0001) greater for the most predisposed tenth. The greater increase in BMI in genetically predisposed individuals over time was apparent after adjustment for family-level confounding using a sibling design. Key limitations include a slightly lower survival to date of genetic testing for the older cohorts and that we apply a contemporary genetic score to past time periods. Future research should validate our findings using a polygenic risk score constructed from historical data. CONCLUSIONS: In the context of increasingly obesogenic changes in our environment over 6 decades, our findings reveal a growing inequality in the risk for obesity and severe obesity across GPS tenths. Our results suggest that while obesity is a partially heritable trait, it is still modifiable by environmental factors. While it may be possible to identify those most susceptible to environmental change, who thus have the most to gain from preventive measures, efforts to reverse the obesogenic environment will benefit the whole population and help resolve the obesity epidemic.

Associations between complex multimorbidity, activities of daily living and mortality among older Norwegians. A prospective cohort study: the HUNT Study, Norway.

BACKGROUND: With increasing age, having multiple chronic conditions is the norm. It is of importance to study how co-existence of diseases affects functioning and mortality among older persons. Complex multimorbidity may be defined as three or more conditions affecting at least three different organ systems. The aim of this study was to investigate how complex multimorbidity affects activities of daily living and mortality amongst older Norwegians. METHODS: Participants were 60-69-year-olds at baseline in the Nord-Trøndelag Health Study 1995-1997 (HUNT2) n = 9058. Multinomial logistic regression models were used to investigate the association between complex multimorbidity in HUNT2, basic and instrumental activities of daily living in HUNT3 (2006-2008) and mortality during follow-up (n = 5819/5836). Risk ratios (RR) and risk differences (RD) in percentage points (pp) with 95% confidence intervals (CI) were reported. RESULTS: 47.8% of 60-69-year-olds met the criteria of complex multimorbidity at baseline (HUNT2). Having complex multimorbidity was strongly associated with the need for assistance in IADL in HUNT3 11 years later (RR = 1.80 (1.58-2.04) and RD = 8.7 (6.8-10.5) pp) and moderately associated with mortality during the follow-up time (RR = 1.22 (1.12-1.33) and RD = 5.1 (2.9-7.3) pp). Complex multimorbidity was to a lesser extent associated with basic activities of daily living 11 years later (RR = 1.24 (0.85-1.83) and RD = 0.4 (- 0.3-1.1) pp). CONCLUSIONS: This is the first study to show an association between complex multimorbidity and activities of daily living. Complex multimorbidity should receive more attention in order to prevent future disability amongst older persons.

Prevalence, clustering and combined effects of lifestyle behaviours and their association with health after retirement age in a prospective cohort study, the Nord-Trøndelag Health Study, Norway.

BACKGROUND: Lifestyle behaviours are potential risk factors for disease and mortality, but less is known about the association with health in retirement age. The aim of this paper was to study the prevalence, clustering and combined effects of lifestyle behaviours and their association with health outcomes in the first decade after retirement in a Norwegian cohort. METHODS: Participants were 55-64-year-olds at baseline in the Nord-Trøndelag Health Survey 2 (HUNT2, 1995-97) who also participated in HUNT3 (2006-08). Logistic regression analyses were used to investigate the association of daily smoking, physical inactivity, risky alcohol consumption, disturbed sleep duration, excessive sitting time and low social participation before retirement with self-rated health (n = 4022), life satisfaction (n = 5134), anxiety (n = 4461) and depression (n = 5083) after retirement, 11 years later. RESULTS: Low social participation and physical inactivity were the most prevalent lifestyle behaviours (41.1 and 40.6%). Risky alcohol consumption and disturbed sleep were the lifestyle behaviours most strongly associated with poor self-rated health, poor life satisfaction and anxiety after retirement (OR's = 1.39-1.92). Physical inactivity was additionally associated with depression (OR = 1.44 (1.12-1.85)). Physical inactivity had the largest population attributable fractions for reducing poor self-rated health and depression (14.9 and 8.8%). An increasing number of lifestyle risk behaviours incrementally increased the risk for the adverse health outcomes. CONCLUSIONS: Risky alcohol consumption and disturbed sleep duration were most strongly associated with poor health outcomes after retirement age. On a population level, increased physical activity before retirement had the largest potential for reducing adverse health outcomes after retirement age.

The diffusion of innovative diabetes technologies as a fundamental cause of social inequalities in health. The Nord-Trøndelag Health Study, Norway.

This study investigates patterns of adoption and diffusion of innovative health technologies by socioeconomic status (SES) in order to assess the extent to which these technologies may be a fundamental cause of health-related inequalities. Quantitative analyses examined SES-based inequalities in the adoption and diffusion of diabetes technologies. Diabetes data from three panels of the Nord-Trøndelag Health Study (HUNT), Norway, were combined with income and education data. Cross-sectional and longitudinal regression analyses were used to examine relevant inequalities. Cross-sectional analyses suggest often present SES-based gradients in the adoption of diabetes technologies, favouring high-SES groups. Statistically significant differences (p ≤ 0.05) were most often present when technologies were new. In a cohort followed from 1984 to 1997, high SES individuals were more likely to adopt insulin injection technologies but, due to modest sample sizes, these inequalities were not statistically significant after adjusting for age, gender, and duration of illness. Moreover, compared to low SES individuals, high SES individuals are more active users of diabetes technologies. Results suggest that SES-based variations in access and use of innovative health technologies could act as a mechanism through which inequalities are reproduced. This study provides a discussion of mechanisms and a methodological foundation for further investigation.

Decennial trends and inequalities in healthy life expectancy: The HUNT Study, Norway.

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.

Multiple lifestyle behaviours and mortality, findings from a large population-based Norwegian cohort study - The HUNT Study.

BACKGROUND: Lifestyle risk behaviours are responsible for a large proportion of disease burden and premature mortality worldwide. Risk behaviours tend to cluster in populations. We developed a new lifestyle risk index by including emerging risk factors (sleep, sitting time, and social participation) and examine unique risk combinations and their associations with all-cause and cardio-metabolic mortality. METHODS: Data are from a large population-based cohort study in a Norway, the Nord-Trøndelag Health Study (HUNT), with an average follow-up time of 14.1 years. Baseline data from 1995-97 were linked to the Norwegian Causes of Death Registry. The analytic sample comprised 36 911 adults aged 20-69 years. Cox regression models were first fitted for seven risk factors (poor diet, excessive alcohol consumption, current smoking, physical inactivity, excessive sitting, too much/too little sleep, and poor social participation) separately and then adjusted for socio-demographic covariates. Based on these results, a lifestyle risk index was developed. Finally, we explored common combinations of the risk factors in relation to all-cause and cardio-metabolic mortality outcomes. RESULTS: All single risk factors, except for diet, were significantly associated with both mortality outcomes, and were therefore selected to form a lifestyle risk index. Risk of mortality increased as the index score increased. The hazard ratio for all-cause mortality increased from 1.37 (1.15-1.62) to 6.15 (3.56-10.63) as the number of index risk factors increased from one to six respectively. Among the most common risk factor combinations the association with mortality was particularly strong when smoking and/or social participation were included. CONCLUSIONS: This study adds to previous research on multiple risk behaviours by incorporating emerging risk factors. Findings regarding social participation and prolonged sitting suggest new components of healthy lifestyles and potential new directions for population health interventions.

Blood pressure changes during 22-year of follow-up in large general population - the HUNT Study, Norway.

BACKGROUND: While hypertension still is a major health problem worldwide, some studies have indicated that the blood pressure level has decreased in some populations. This population based cohort study aims at analysing blood pressure changes in a large Norwegian population over a 22 year period. METHODS: Data is acquired from three comprehensive health surveys of the HUNT Study conducted from 1984-86 to 2006-08. All citizens of Nord-Trøndelag County, Norway, >20 years were invited: 74,549 individuals participated in 1984-86; 64,523 in 1995-97; and 43,905 in 2006-08. RESULTS: Both systolic and diastolic blood pressure levels decreased substantially from mid 1980s to mid 2000s, with the most pronounced decrease from 1995-97 to 2006-08 (from 136.0/78.9 to 128.3/70.9 mmHg in women and from 140.1/82.1 to 133.7/76.5 mmHg in men). Although the use of blood pressure lowering medication increased, there was a considerable decrease even in those who reported never use of medication (mean decrease 6.8/7.2 mmHg in women and 6.3/5.3 mmHg in men), and the decrease was most pronounced in the elderly (mean decrease 16.1/12.4 mmHg in women and 14.7/10.4 mmHg in men aged 80+). Mean heart rate, total cholesterol and daily smoking decreased, self-reported hard physical activity increased, while body weight and the prevalence of diabetes increased during the same period. CONCLUSIONS: The BP decrease might seem paradoxically, as body weight and prevalence of diabetes increased during the same period. Salt consumption might have decreased, but no salt data is available. The parallel decrease in mean heart rate might indicate reduction in the white-coat phenomenon, or increased use of beta blockers or calcium channel blockers for other diagnosis than hypertension. Additionally, the data could support the "healthy obese" hypothesis, i.e., that subgroups in the population can sustain obesity without serious health consequences.