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

A.2
A.2. Scientific background and rationale for study elements
significantly to cognitive impairment and subsequently to the development of dementia, and
that active engagement in mental, physical, and social activities may postpone the decline in
function and the onset of dementia by providing cognitive reserve90 . Vascular brain changes
are thought to reduce cerebral perfusion and hypoperfusion and have been found to cause
oxidative stress, neurodegeneration, and cognitive decline91 . Mild cognitive impairment is defined
as an intermediate state between normal cognitive function and dementia and is further
described in Sect. A.2.3.4.
Assessment of major cognitive impairement and dementia:
Examinations and questionnaires (at baseline and during reassessment)
Level 1: Questionnaires
Neuropsychological test battery
MRI program: Brain MRI
Active follow-up (and medical verification of self-reports):
Self-reports, proxy reports, or reports by the participant’s general physician of physician-diagnosed
Alzheimer’s disease, or dementia
Depression and anxiety: Mood and anxiety disorders represent the most frequent mental
illnesses in Germany. They generally develop more often in women than in men. During
lifetime, about one of four women and one in ten men are affected at least once by depression.
Major depression is known to have a high comorbidity with CVD 92, 93 , metabolic syndrome,
and diabetes 94-96 and atopic, neurologic, and infectious diseases, where it is judged
to be likely that depression is not only a frequent consequence of a somatic disease, but
can also be an important, independent risk factor. The pathophysiology of major depression
is complex and not well understood. Previous studies suggested that systemic, low-grade
inflammation may play a role in the onset and course of disease 97 . These studies showed
that major depression is accompanied by biochemical and immune changes, suggesting the
presence of either an acute or a chronic inflammatory process 98-101 . Important determinants
of the inflammatory process are the release of cytokines and alterations in iron metabolism,
characterized by decreased serum iron and transferrin levels associated with normal or increased
ferritin levels 102, 103 . With regard to anxiety disorders, the 12-month prevalence is as
high as 14.5% 104 , and anxiety is the most common comorbidity for depression, accounting for
about 19% of all occurring comorbidities among mental disorders. Marital status (living alone,
being divorced, or widowed) and unemployment seem to be risk factors for anxiety disorders
in both genders. Current research in anxiety disorders is also exploring the neurobiology and
genetic basis for these conditions, especially of panic attacks.
Assessment of depression and anxiety:
Examinations and questionnaires (at baseline and during reassessment)
Level 1: Questionnaires (incl. depression and anxiety scores)
Active follow-up:
Self-report of physician-diagnosed depression or anxiety disorders
headache: Primary headache disorders, including migraine and tension-type headache,
affect millions of people worldwide 105 . The burden of headache has consequences for the
individual and for society due to a reduced quality of life, absenteeism and lower performance
at work, and increased disease-related costs 106 . Although acute and prophylactic
treatments are available, many frequent headache sufferers either do not seek treatment
or do not respond satisfactorily to these treatment strategies 107 . Behavior-dependent, socalled
lifestyle factors have been of interest in studies that have previously investigated the
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