Metabolic syndrome predicts prostate cancer in a cohort of middle-aged Norwegian men followed for 27 years.

The aim of the study was to establish whether metabolic syndrome predicts the incidence of prostate cancer. The hypothesis was tested using the 27-year follow-up of the prospective cohort of 16,209 men aged 40-49 years who participated in the Oslo Study in 1972-1973. Men with established diabetes and men with cancer diagnosed before screening were excluded, leaving 15,933 for analyses. Metabolic syndrome is here composed of body mass index, nonfasting glucose, triglycerides, and blood pressure or drug-treated hypertension. Two analytical approaches were compared, namely, predefined (adjusted from National Cholesterol Education Program) and quartile values of risk factors. Age, body mass index, and sedentary versus intermediate physical activity at work were significant predictors in univariate proportional hazards regression analyses. Combinations of any two (relative risk = 1.23; p = 0.04) or any three (relative risk = 1.56; p = 0.00) factors of the metabolic syndrome using quartile values of risk factors were predictive of prostate cancer. The number of cases for four factors was too small for analyses. Predefined values of the risk factors were not found to be predictive. In conclusion, metabolic syndrome was found to predict prostate cancer during 27 years of follow-up, indicating an association between insulin resistance and the incidence of prostate cancer.

Risk factors associated with body mass index increase in men at 28 years follow-up.

BACKGROUND: Several studies have reported a general increase in body mass index (BMI). AIM: To identify factors influencing BMI changes at 28 years follow-up. DESIGN: Prospective screening study. METHODS: The cohort of the Oslo I study of 1972/73 had another screening in 2000 (Oslo II). We present data for these men, and men from Oslo I who participated in five similar studies during 1996-2001. In all, 7157 men aged 20-49 years at first screening attended two health screenings, and complete data were available for 7104. BMI change from 1972/73 to 2000 was the dependent variable in multiple regression analyses. RESULTS: The percentage with obesity (BMI > or = 30) increased overall from 2.5% to 13.5%. The overall mean (SD) BMI increased from 24.2 (2.6) kg/m2 to 26.2 (3.4) kg/m2. The increase was largest (3.9 (2.5) kg/m2) among men aged 20-24 in 1972/73 and least (1.6 (2.5) kg/m2) in those aged 45-49 years. No age trend was observed for those with BMI > or = 30.0 kg/m2 in 1972/3. On multiple regression analysis, increasing triglycerides, systolic blood pressure, age and non-fasting glucose, decreasing physical activity and not smoking were all significantly related to increasing BMI. Having stopped smoking was also related to increased BMI. Daily smoking in both 1972/73 and 2000, and daily smoking in 2000 but not in 1972/73, were inversely related to increased BMI. DISCUSSION: There was a substantial increase in BMI, with the largest increase in the younger men, except in those who were already obese at first screening. Overall, obesity increased by 11% in the study period and was associated with multiple life-style factors.

Psychosocial risk factors and mortality: a prospective study with special focus on social support, social participation, and locus of control in Norway.

STUDY OBJECTIVE: The objective is to investigate the effect on mortality of psychosocial variables, with special focus on social support, social participation, and locus of control. DESIGN: The study is designed as a prospective study with a 17 year follow up period, using univariate and multivariate proportional hazards regression analysis to estimate the predictive power of psychosocial variables, when controlling for sociodemographic and biological factors. SETTING: The study is based on a population sample randomly drawn from different neighbourhoods of Oslo in 1975/76, for the purpose of surveying health, in particular mental health, in relation to various social and psychosocial variables. The initial data were gathered by structured interviewing, whereas the data about mortality and cause of death, was gathered from the Central Bureau of Statistics. PARTICIPANTS: The initial sample included 1010 persons above the age of 18 years, with no upper age limit. The follow up with respect to mortality covered the whole sample, with the exception of a very few who had left the country. MAIN RESULTS: When controlling for socio-demographic and biological factors, low social participation, and to a lesser extent, few close relationships and external locus of control, were associated with increased mortality. CONCLUSION: The effect of social participation and locus of control may indicate that life style, and individual psychological resources, are at least as important for survival as support from others in stressful life situations.