Background: The heterogeneity of late-life depression hampers diagnosis and treatment. Data-driven methods have identified several subtypes of depression in older persons, but the longitudinal... Show moreBackground: The heterogeneity of late-life depression hampers diagnosis and treatment. Data-driven methods have identified several subtypes of depression in older persons, but the longitudinal stability of these subtypes remains unknown.Methods: In total 111 older persons with a major depressive disorder both at baseline and 2-year follow-up from the Netherlands Study of Depression in Older persons (NESDO) were included. Latent class analysis was performed to identify subtypes of depression at baseline and at 2-year follow-up, and latent transition analysis was used to examine the stability of these subtypes over time. Transition rates between subtypes and characteristics of groups were examined.Results: Two subtypes were identified in both baseline (TO) and follow-up data (T1), including a 'melancholic' subtype (prevalence 80.2% (T0) and 62.2% (T1)), and an 'atypical' subtype (prevalence 19.8% (T0) and 37.8% (T1)). The melancholic subtype was characterized by decreased appetite and weight and had a stability of 0.86. The atypical subtype was characterized by increased appetite and weight and had a stability of 0.93, although the discriminating power of different symptoms had decreased at Tl. Mean age and education differed significantly between stable and transitioning subgroups, other characteristics did not differ between subgroups.Limitations: Limited sample size might have hampered the analyses.Conclusions: Subtypes of late-life depression are relatively stable, but symptoms of depression (like weight loss) seem to blur with symptoms of (patho)physiological aging. This underlines the clinical relevance of depression subtyping, but also the importance of further research into subtypes and the influence of aging. Show less
In this thesis the heterogeneity of late-life depression is being examined. The first part of the thesis focuses on data-driven analyses as a way of identifying subtypes of late-life depression.... Show moreIn this thesis the heterogeneity of late-life depression is being examined. The first part of the thesis focuses on data-driven analyses as a way of identifying subtypes of late-life depression. Through latent class analysis, we have identified three subtypes: a severe melancholic subtype, an atypical subtype, and a moderately severe subtype. These subtypes had different sociodemographic and clinical characteristics, but no specific biological disturbances could be addressed to the different subtypes. This is probably because of the tangle of (patho)physiological processes in aging itself, muddling the results. The stability of these subtypes over a two-year follow-up was however high, strengthening the clinical relevance of found subtypes.The second part of this thesis examines psychomotor disturbances in melancholic depression as a possible predicting symptom of response in electroconvulsive therapy. We have found that psychomotor disturbances predict to a certain amount the response to electroconvulsive therapy, but this effect was overruled by the predictive value of psychotic symptoms in depression. Finally, we have examined the speed of response of different depressive symptoms on electroconvulsive therapy in older depressed persons, and have found that all ten symptoms show response in two weeks, underlining the safety and efficacy of electroconvulsive therapy in older persons. Show less
