Leukocyte telomere length and late-life depression

Depressive disorders have been associated with increased risk for aging-related diseases, possibly as a consequence of accelerated cellular aging. Cellular aging, indexed by telomere length (TL) shortening, has been linked to depression in adults younger than 60 years; however, it remains unclear whether this is the case in late-life depression (age >60 years). The objective of this study was to assess differences in TL between persons with current late-life depression and never-depressed comparisons and to examine the association between characteristics of late-life depression and TL.

In this cross-sectional study using the Netherlands Study of Depression in Older Persons, 355 persons with current late-life depression and 128 never-depressed comparisons, aged 60-93 years (mean age [SD]: 70.5 [7.4] years, 65% women), were recruited through primary care and mental healthcare. Late-life depression was established using a Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition-based structured psychiatric interview. Leukocyte TL, expressed in base pairs (bp), was determined in fasting blood samples by performing quantitative polymerase chain reaction.

Mean TL did not differ between depressed persons (bp [SD]: 5,035 [431]) and never-depressed (bp [SD]: 5,057 [729]) comparisons. Further, TL was not associated with severity, duration, and age at onset of depression; comorbid anxiety disorders; anxiety symptoms; apathy severity; antidepressant use; benzodiazepine use; cognitive functioning; and childhood trauma.

Late-life depression was not associated with increased cellular aging. This absent association, which contradicts observations in younger adults, may be due to the potential larger heterogenic nature of late-life depression and lifetime cumulative exposure to other TL-damaging factors, possibly overruling effects of late-life depression.