Metabolic syndrome and risk of incident psoriasis: prospective data from the HUNT Study, Norway.

BACKGROUND: Metabolic syndrome has been associated with psoriasis in cross-sectional studies, but data from prospective studies are sparse. OBJECTIVES: To examine prospectively whether metabolic syndrome and its components are associated with the risk of incident psoriasis in a large population-based study using objective measurements of cardiovascular disease risk factors. METHODS: We used data from two consecutive surveys of the HUNT Study, Norway (HUNT2, 1995-1997, and HUNT3, 2006-2008). In total 34 996 women and men aged ≥ 20 years without psoriasis in HUNT2 were followed up in HUNT3, and 374 incident cases of psoriasis were identified. We used Cox regression to estimate the adjusted relative risk (RR) of incident psoriasis with its 95% confidence interval (CI). RESULTS: Metabolic syndrome was associated with an RR for psoriasis of 1·66 (95% CI 1·30-2·14). To explore the influence of adiposity on this association, we first excluded waist circumference from the definition of metabolic syndrome (adjusted RR 1·54, 95% CI 1·14-2·07) and then adjusted for body mass index (RR 1·33, 95% CI 0·97-1·81). Analyses of the separate components of metabolic syndrome showed positive associations with risk of psoriasis for waist circumference, triglycerides and high-density lipoprotein (HDL) cholesterol, but not for blood pressure or blood glucose. There was also an increased risk of psoriasis for high total cholesterol. The increased risk associated with high triglycerides, HDL cholesterol and total cholesterol was attenuated after adjusting for body mass index. CONCLUSIONS: In this large prospective study from a general population, we found that metabolic syndrome was associated with increased risk of incident psoriasis, and our results suggest that this positive association could, at least partly, be attributed to adiposity.

Parental chronic widespread pain and the association with chronic widespread pain in adult offspring: Family-linkage data from the Norwegian HUNT Study.

BACKGROUND: Individuals experiencing chronic widespread pain (CWP) have greater disability and poorer quality of life compared to those with other chronic painful conditions; although research identifying risk factors for CWP is lacking. We aimed to investigate whether parental CWP increases the risk of offspring CWP, and if offspring body mass index (BMI) and leisure time physical activity modify this association. METHODS: We included 6589 parent-offspring trios participating in the Norwegian HUNT Study in 1995-1997 and 2006-2008. Logistic regression was used to calculate adjusted odd ratios (ORs) (95% confidence intervals, CIs) as estimates of relative risk for offspring CWP. We analysed the joint effect of parental CWP and offspring BMI or leisure time physical activity on offspring risk of CWP and calculated the relative excess risk due to interaction (RERI). RESULTS: In total, 886 (13.5%) offspring developed CWP during follow-up. Having one (OR = 1.23, 95% CI, 1.05-1.44) or both parents with CWP (OR = 1.89, 95% CI, 1.50-2.38) increased the risk of offspring CWP. In analyses of joint effects, ORs were 1.84 (95% CI, 1.31-2.56) and 3.35 (95% CI, 1.94-5.77) in normal weight and obese offspring, respectively, when both parents had CWP. The estimate of RERI suggested some synergistic effect (RERI = 1.19, 95% CI, -0.68 to 3.05), although precision was low. Risk of CWP was similar in active (OR = 2.05, 95% CI, 1.56-2.70) and inactive (OR = 1.96, 95% CI, 1.31-2.91) offspring when both parents had CWP. CONCLUSION: Parental CWP increases the risk of CWP in adult offspring, particularly if both parents have CWP and offspring are obese. This highlights a familial predisposition for CWP and an important target group for preventive measures. SIGNIFICANCE: The parent-offspring transmission of CWP is stronger in obese offspring (particularly when both parents have CWP). This study is the first to investigate the interaction between modifiable lifestyle factors, familial factors and CWP.

Psoriasis and cardiovascular disease risk factors: the HUNT Study, Norway.

BACKGROUND: Studies have examined the associations between psoriasis and cardiovascular diseases and their risk factors, but the results are conflicting, especially in the general population. OBJECTIVES: To investigate the association of psoriasis, and in particular psoriasis severity, with objectively measured cardiovascular disease risk factors and cardiovascular morbidity in a large population-based cross-sectional study. METHODS: We linked data on 50 245 persons in the HUNT3 Study, Norway, with information from the National Prescription Database to obtain information on use of psoriasis medication. A total of 2894 persons reported to have psoriasis; 2643 were classified as mild; and 251 as moderate/severe psoriasis. We used linear and logistic regression to estimate adjusted associations with 95% confidence intervals (CIs) between psoriasis and cardiovascular disease risk factors and morbidity. RESULTS: We observed a positive association between psoriasis and objective measures of body mass index (BMI), waist circumference and high-sensitivity C-reactive protein, but no clear association with blood pressure and blood lipids. People with moderate/severe psoriasis had an odds ratio for being overweight of 1.94 (95% CI 1.42, 2.67), whereas the odds ratio for metabolic syndrome was 1.91 (95% CI 1.47, 2.49). Psoriasis was also positively associated with self-reported diabetes, myocardial infarction and angina pectoris. CONCLUSIONS: In this population-based study, we found that psoriasis was positively associated with measures of adiposity, as well as with a clustering of cardiovascular disease risk factors. Overall, these associations were strongest for people with moderate/severe psoriasis.

Leisure-time physical activity and disability pension: 9 years follow-up of the HUNT Study, Norway.

The objective of this study was to prospectively examine the association between leisure-time physical activity and risk of disability pension, as well as risk of disability pension because of musculoskeletal or mental disorders in a large population-based cohort. Data on participants aged 20-65 years in the Norwegian Nord-Trøndelag Health Study 1995-1997 (HUNT2) were linked to the National Insurance Database. Cox regression was used to calculate hazard ratios (HR) and 95% confidence intervals for disability pension across physical activity categories. During a follow-up of 9.3 years and 235,657 person-years, 1266 of 13,823 men (9%) and 1734 of 14,531 women (12%) received disability pension. Compared with individuals in the inactive group, those in the highly active group had a 50% lower risk of receiving disability pension (HR for men: 0.50, 0.40-0.64; women: 0.50, 0.39-0.63). After comprehensive adjustment for potential confounders, the risk remained 32-35% lower (HR for men: 0.68, 0.53-0.86; women: 0.65, 0.51-0.83). The associations were stronger for disability pension due to musculoskeletal disorders than mental disorders. In summary, we observed strong inverse associations between leisure-time physical activity and disability pension. Our findings strengthen the hypothesis that leisure-time physical activity may be important for occupational health in reducing disability pension.

Neck/upper back and low back pain in parents and their adult offspring: Family linkage data from the Norwegian HUNT Study.

BACKGROUND: Chronic pain in the neck and low back is highly prevalent. Although heritable components have been identified, knowledge about generational transmission of spinal pain between parents and their adult offspring is sparse. METHODS: This study examined the intergenerational association of spinal pain using data from 11,081 parent-offspring trios participating in the population-based HUNT Study in Norway. Logistic regression was used to calculate adjusted odds ratios (ORs) with 95% confidence intervals (CIs) for offspring spinal pain associated with parental spinal pain. RESULTS: In total, 3654 (33%) offspring reported spinal pain at participation. Maternal and paternal spinal pain was consistently associated with higher ORs for offspring spinal pain. The results suggest a slightly stronger association for parental multilevel spinal pain (i.e., both neck/upper back pain and low back pain) than for pain localized to the neck/upper back or low back. Multilevel spinal pain in both parents was associated with ORs of 2.6 (95% CI, 2.1-3.3), 2.4 (95% CI, 1.9-3.1) and 3.1 (95% CI, 2.2-4.4) for offspring neck/upper back, low back and multilevel spinal pain, respectively. CONCLUSION: Parental chronic spinal pain was consistently associated with increased occurrence of chronic spinal pain in their adult offspring, and this association was particularly strong for multilevel spinal pain.

Physical exercise, body mass index and risk of chronic arm pain: longitudinal data on an adult population in Norway.

AIM: The aim of this study was to prospectively investigate the association between leisure time physical exercise, body mass index (BMI) and risk of chronic arm pain. METHODS: The study population comprises 14,041 women and 13,674 men in the Norwegian HUNT Study without musculoskeletal pain or physical impairment at baseline in 1984-86. Chronic arm pain was assessed at follow-up in 1995-97. A generalized linear model was used to calculate adjusted relative risks (RRs). RESULTS: At follow-up, 2205 women and 1458 men reported chronic arm pain. Level of physical exercise was inversely associated with risk of chronic arm pain (P-trend, ≤0.03 for both sexes). Compared with inactive persons, women and men who exercised ≥ 2 h/week had adjusted RRs of 0.84 [95% confidence interval (CI), 0.73-0.96] and 0.74 (95% CI, 0.63-0.87), respectively. BMI was positively associated with risk of chronic arm pain (P-trend, ≤0.002 for both sexes). Compared with normal-weight persons, women and men classified as obese (BMI ≥ 30 kg/m2) had adjusted RRs of 1.26 (95% CI, 1.11-1.44) and 1.29 (95% CI, 1.07-1.57), respectively. Combined analysis showed that obese women and men who exercised ≥ 1 h/week had a RR of 1.20 (95% CI 0.97-1.48) compared with normal-weight women and men with a similar activity level, whereas the RR was 1.41 (95% CI 1.21-1.65) for obese women and men who were physically inactive. CONCLUSION: Regular physical exercise reduces risk of chronic arm pain while high BMI increases the risk. Exercise can to some extent compensate for the adverse effect of obesity on risk of chronic arm pain.

Association of size at birth with adolescent hormone levels, body size and age at menarche: relevance for breast cancer risk.

Birth size has been positively associated with age at menarche and height in adolescence and adulthood, but the relevant biological mechanisms remain unclear. Among 262 Norwegian term-born singleton girls, birth size measures (weight, length, ponderal index, head circumference and subscapular skin-fold thickness) were analysed in relation to adolescent hormone levels (oestradiol, prolactin, dehydroepiandrosterone sulphate, androstenedione and free testosterone index), age at menarche and adolescent (ages 12.7-15.5 years) and body size (height, weight, body mass index and waist-to-hip ratio) using survival analysis and general linear modelling. The results were adjusted for gestational age at birth, age and menarcheal status at measurement in adolescence and maternal age at menarche. Birth weight, birth length and head circumference were positively associated with adolescent weight and height, and small birth size was associated with earlier age at menarche. Subscapular skin-fold thickness at birth was not associated with adolescent body size, but low fold-thickness was associated with earlier age at menarche. Measures of birth size were inversely related to circulating levels of dehydroepiandrosterone sulphate in adolescence, but there was no clear association with other hormones. These results suggest that physical and sexual development in puberty and adolescence is influenced by prenatal factors, and in combination, these factors may influence health and disease later in life.

Blood pressure and renal cancer risk: the HUNT Study in Norway.

In a prospective study of 36,728 women and 35,688 men during 18 years of follow-up, compared to systolic pressure <130 mm Hg, levels of 130-149, 150-169 and >or=170 mm Hg in women were associated with relative risks of renal cell cancer of 1.7, 2.0 and 2.0, respectively (P for linear trend, 0.11). In men, there was no association with blood pressure.

The negative association between pre-eclampsia and breast cancer risk may depend on the offspring's gender.

If the negative association between pre-eclampsia and subsequent breast cancer risk differs by gender, this would strengthen the hypothesis that factors intrinsic to the particular pregnancy may explain the association. The study included 701,006 parous Norwegian women with follow-up for breast cancer through the Cancer Registry of Norway. Breast cancer risk was lower in women with pre-eclampsia/hypertension in their first pregnancy, compared to other women (relative risk, 0.86, 95% CI, 0.78-0.94), after adjustment for age at first birth, maternal birth year, length of gestation, marital status, and parity. The risk reduction was slightly greater if the woman delivered a son as opposed to a daughter (relative risks of 0.79 vs 0.94, P-value for interaction, 0.06), and if pre-eclampsia/hypertension was combined with pre-term delivery, these differences were more pronounced (relative risks, 0.62 vs 1.07, P-value for interaction 0.03). A subanalysis among 176,036 primiparous women showed a substantial risk reduction if the mother delivered a son (relative risk, 0.62, 95% CI, 0.47-0.82), but essentially null if she delivered a daughter (relative risk, 0.92, 95% CI, 0.72-1.18; P-value for interaction, 0.05). These results suggest that the effect of pre-eclampsia/hypertension may be attributed to factors associated with the particular pregnancy rather than an underlying biological trait of the mother. The stronger risk reduction related to having a son suggests a role for sex-dependent hormones in pregnancy.

Change in height, weight and body mass index: Longitudinal data from the HUNT Study in Norway.

OBJECTIVE: The aim of this study was to analyse changes in body weight and height, and the changes in the prevalence of overweight and obesity. DESIGN: Prospective population based study with 11-year follow-up. SUBJECTS: Norwegian men (n=21565) and women (n=24337) aged 20 years or more who participated in two health surveys, the first in 1984-1986 and the other in 1995-1997. MEASUREMENTS: Height and weight were measured by using standardised procedures at both surveys, and we computed body mass index (BMI) as weight in kilo divided by the squared value of height in meters. RESULTS: Participants who were younger than 50 years at the first survey showed a large increase in body weight, and men and women aged 20-29 years increased their weight with an average of 7.9 kg and 7.3 kg, respectively. Contradictory, participants who were 70 years or older had on average a weight loss. The prevalence of overweight (BMI=25.0-29.9 kg/m(2)) and obesity (BMI>/=30 kg/m(2)) increased between the surveys, especially in the youngest age groups. Overall, the proportion classified as obese increased from 6.7 to 15.5% among men and from 11.0 to 21.0% among women. Some of this increase was due to a reduction in height, which was most pronounced in the oldest age groups. CONCLUSION: During approximately 10 years, body weight increased in all age groups below 70 years, and the prevalence of overweight and obese persons was approximately 20% higher at the second survey compared with the first survey.

Serum lipids and anthropometric factors related to the prevalence of intermittent claudication.

PURPOSE: To study serum lipids, body mass index (BMI), and body shape in relation to intermittent claudication (IC) in 19,748 men and women 40-69 years of age. METHOD: All residents (1995-1997) in Nord-Trøndelag County, Norway, were invited to attend the cross sectional study and received a Norwegian translation of the WHO/Rose questionnaire on intermittent claudication and the Edinburgh claudication questionnaire. Blood lipids and anthropometric data were measured at a consecutive examination. Odds ratios (OR) were estimated for associations with IC by multiple regression analysis. RESULTS: The ratio of total cholesterol to HDL cholesterol (TC/HDL cholesterol) (P trend(men)=.023; P trend(women)<.001) and triglycerides (P trend(men)=.029; P trend(women)=.002) were positively associated with the prevalence of IC. HDL cholesterol was negatively (P trend(men)=.131; P trend(women)<.001) associated, whereas BMI (P trend(women)=.032), waist circumference (P trend(women)=.021), and hip circumference (P trend(women)=.020) were positively associated with IC in women, but not in men. Adjustment for smoking, diabetes, and systolic or diastolic blood pressure did not change the results. CONCLUSION: TC/HDL cholesterol and triglycerides were positively, and HDL cholesterol negatively associated with IC in both genders. In women, but not in men, BMI, waist and hip circumference were positively associated with IC.

Change in body mass index and its impact on blood pressure: a prospective population study.

BACKGROUND: Overweight and obesity increase the risk of elevated blood pressure, but the knowledge of the effect of weight change on blood pressure is sparse. OBJECTIVE: To investigate the association between change in body mass index (BMI) and change in diastolic blood pressure (DBP), systolic blood pressure (SBP), and hypertension status. DESIGN: Two population-based cross-sectional studies, one in 1984-86 and the other in 1995-97. SETTING: The Nord-Trondelag Health Study (HUNT). PARTICIPANTS: We included 15,971 women and 13,846 men who were 20 y or older at the first survey, without blood pressure medication at both surveys and without diabetes, cardiovascular disease or dysfunction in daily life at baseline. MEASUREMENTS: Weight, height and blood pressure were measured standardised. Change in BMI was categorised as stable (initial BMI+/-0.1 kg/m2 each follow-up year), increased or decreased, and BMI was categorised by using World Health Organisation's categorisation (underweight BMI: <18.5 kg/m2, normal weight BMI: 18.5-24.9 kg/m2, overweight BMI: 25.0-29.9 kg/m2, obesity BMI> or =30 kg/m2). RESULTS: An increase in BMI and a decrease in BMI were significantly associated with increased and decreased SBP and DBP, respectively, compared to a stable BMI in both genders and all age groups, although the strongest effect was found among those who were 50 y and older. The adjusted odds ratio for having hypertension at HUNT 2 was 1.8 (95% confidence interval (CI): 1.5, 2.2) among women and 1.6 (95% CI: 1.4,1.8) among men aged 20-49 y who increased their BMI compared to those who had stable BMI. A similar, but weaker association was found among women and men aged 50 y or more. The mean change in both SBP and DBP was higher for those who changed BMI category from first to the second survey than for those who were in the same BMI class at both surveys. CONCLUSIONS: Our result supports an independent effect of change in BMI on change in SBP and DBP in both women and men, and that people who increase their BMI are at increased risk for hypertension.

Birth size and colorectal cancer risk: a prospective population based study.

OBJECTIVE: To study whether birth size influences colorectal cancer risk in adulthood. DESIGN: A cohort of Norwegian men and women identified from midwives' birth records with long term cancer follow up through the Norwegian Cancer Registry. SETTING: St Olav's University Hospital, Trondheim, Norway. PARTICIPANTS: 16,016 women and 19 681 men born between 1920 and 1958 and alive in 1960. OUTCOME MEASURES: Incidence rate ratios (RRs) for colorectal cancer with 95% confidence intervals (CIs) and two sided p values for trend across categories of birth dimensions. RESULTS: Men whose birth length was less than 51 cm had a nearly twofold higher risk of colorectal cancer (RR 1.9 (95% CI 1.0-3.7)) compared with men who were 53 cm or more, after adjustment for birth cohort, maternal age at childbearing, length of gestation, gestational hypertension or pre-eclampsia, birth order, maternal height, and indicators of maternal socioeconomic status. The association displayed a linear trend across categories of birth length (p(trend) = 0.03). Among men, similar associations were found for birth weight and head circumference, but for women there was no association between any of these birth dimensions and risk of colorectal cancer. CONCLUSION: The results suggest that among men, but not women, being relatively short at birth is associated with increased risk of colorectal cancer in adulthood, indicating that intrauterine growth could be important for colorectal carcinogenesis.