Scientific Concept of the National Cohort (status ... - Nationale Kohorte

A.2 Scientific background and rationale for study elements
food list (to assess habitual nonconsumers), and the use of nutritional biomarkers, also
including new markers that will emerge, e.g., from studies using metabolomics techniques.
Assessment of diet:
Examinations and questionnaires (at baseline and during reassessment)
Level 1: Repeated simple 24-h diet recalls (web-based application)
Food list
Collection of biomaterials for nutritional biomarker analysis
Level 2: Exact 24-h diet recall (by telephone)
A.2.4.3 Smoking and alcohol consumption
Alcohol is an important risk determinant for cancer and other chronic diseases which has
previously been studied in great depth and with a relatively high accuracy in many studies
267 . An assessment of alcohol intake will be undertaken to account for these known effects,
in analyses addressing the relationships of disease risks with other risk factors.
Smoking is a well-established risk factor 268 , for which no major new findings (relationships
with chronic disease risk) are expected; lifetime smoking history and current smoking habits,
however, must be accurately assessed as major possible confounders in analyses of
relationships with other risk factors or as a possible variable to explain associations, e.g.,
with socioeconomic health disparities.
Assessment of alcohol consumption and smoking behavior:
Examinations and questionnaires (at baseline and during reassessment)
Level 1: Questionnaire
A.2.4.4 Psychosocial factors
Adverse psychosocial factors, such as work-related stress, social isolation, lack of social
support, and negative life events, have been shown to be associated with an increased risk
for CVD 269-271 , diabetes 272-274 , obesity 275 , and depression 276, 277 . Personality traits, on the other
hand, have been shown to be associated with adverse health behavior 278-282 . Several potential
causal mechanisms underlying the adverse health effect of psychosocial factors have
been suggested, involving the hypothalamic-pituitary-adrenal axis, hypertension and blood
pressure reactivity to stress, heart rate variability, endothelial and vascular function, inflammation
and immunity, platelets and coagulation factors, fibrinogen, lipids, and the metabolic
syndrome 270, 283-286 . With regard to cancer, it has been hypothesized that psychosocial factors
may influence incidence directly through altering immune and endocrine functions or
indirectly through health related behaviors, although evidence for a direct causal association
of psychosocial factors with cancer is still scarce 287-289 .
Personality: Five factors of human personality, called the “Big Five”, constitute the most
widely fundamental human personality factors studied, and include “extraversion”, “agreeableness”,
“conscientiousness”, “neuroticism”, and “openness”, although there is considerable
variation to both the exact labeling and meaning given to each of these five dimensions
290 . It has been shown that the “Big Five” factors are relatively stable across human
life cycles, starting in young adulthood 291 . They are at least in part heritable 292, 293 , have
been identified in very different cultures 294 , and probably implied an adaptive value over
the course of human phylogenesis 295 . Research on these five factors of human personality
has highlighted the importance of personality to predict health-relevant behaviors. For
example, extraversion has been linked to smoking, alcohol consumption, and risky sexual
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A.2