Telomere Attrition as a Potential Biomarker of Accelerated Aging in Severe Affective Disorders. A Comparative Study.

Abstract

Background: Severe affective disorders are associated with increased risk of somatic disease, cognitive decline, and premature death. A proposed model of accelerated aging suggests that pathophysiological mechanisms may be intrinsic to the disease itself. Telomere length (TL) attrition is one proposed biomarker of such processes. Evidence suggest that affective illness may be related to accelerated aging represented by shorter TL compared to age-matched controls. Aims: To explore if the occurrence and progression of affective disorders are related to shorter TL in a naturalistic sample of patients compared to age-matched healthy controls. Methods: This cross-sectional study compared TL in blood samples from relatively young patients with DSM-IV severe affective disorders (n = 248) and healthy controls (n = 401). Analyses were performed to investigate whether TL was related to illness duration or number of lifetime affective episodes in the total patient sample. Additional comparisons were made between diagnostic sub-groups of bipolar disorder I (n = 159), bipolar disorder II (n = 67), and major depressive disorder (n = 22). Results: Shorter TL was observed in patients compared to controls (d = 0.18, p = 0.02). Duration of affective illness was negatively associated with TL (b* = -0.18, p = 0.046). No other findings were significant. However, these associations did not remain significant after stringent correction for multiple testing. Conclusions: Trend level variations of TL were potentially due to the young age of participants. Still, the present findings suggest that increased telomere attrition may be linked to both the occurrence and duration of affective disorder in patients relative to healthy controls.