Lifetime depressive and somatic symptoms as preclinical markers of late-onset depression

Background Several risk factors of depression, i.e., female gender and life-stress, have been identified. Few studies have focussed on symptoms as preclinical markers of depression. In these studies current symptoms like dysphoria, tiredness and increased appetite predicted later depression. Even though of possible interest for treatment, no study focussed on lifetime symptoms as preclinical markers of depression. Consequently, we examined lifetime depressive and somatic symptoms with respect to later development of late-onset depression. Methods 664 non-depressed elderly subjects without lifetime diagnoses of depression at the initial examination were selected for a prospective follow-up study (mean follow-up +/- SD: 5.02 +/- 2.44 years). 51 subjects (mean age +/- SD: 66.6 +/- 11.3) developing late-onset depression (defined as depression starting after age 60) were compared to those remaining non-depressed (mean age +/- SD: 59.1 +/- 16.0) during follow-up using the CIDI. To determine the influence of lifetime symptoms on the development of depression, chisquare statistics and multivariate logistic regression analyses were performed. Results The following symptoms being present over a period longer than two weeks were individual preclinical markers of late-onset depression: dysphoria, increased appetite, insomnia, lack of energy, morning depth, lack of joy and interest, inferiority feeling, lack of self-confidence, poor concentration, indecisiveness, thinking about death, wish to die and joint pain. The most important symptoms elevating the risk of late-onset depression in a multivariate model were lack of joy and interest, poor concentration, increased appetite, lack of energy and joint pain. Conclusions Different symptoms can be used individually and in combination to predict later depression. This might allow early treatment.