Anxiety disorders and depression in older adults = Angststoornissen en depressie bij ouderen.

Anxiety and depression are complex disorders caused by both genetic factors and non-genetic factors. However, their etiology is unknown. Study of the epidemiology of anxiety and depression, i.e. study of the occurrence and the determinants of both disorders, helps unravel their etiology. The aim of this thesis (described in Chapter 1) was to help unravel the etiology of anxiety and depression. In particular, comorbidity, health care use, cortisol, atherosclerosis and genetic factors were studied in relation to anxiety and, or depression. The studies in this thesis were based on data from the Rotterdam Study, a prospective population-based cohort study of older adults ongoing since 1990 in Rotterdam, the Netherlands. Every four years participants undergo an extensive home interview and a physical examination at a research center. Cross-sectional data for anxiety disorders and longitudinal data for depression were available for this thesis