Analysis of telomere length and the relationship with neurocognitive functions in euthymic bipolar disorder: a cross-sectional pilot study

Abstract

Abstract Background: Telomere shortening has been considered a potential biological marker related to disease susceptibility and aging in psychiatric disorders. However, the relationship between telomere length and bipolar disorder (BD-I and BD-II) is uncertain. Moreover, whether telomere shortening is an independent factor of cognitive impairment in BD patients is still inconclusive. Methods: We explore telomere length and cognitive function in patients with bipolar disorder and the relationship between them. We enrolled three groups (35 patients with euthymic BD-I, 18 with euthymic BD-II, and 37 healthy controls). Telomere length was measured by fluorescent quantitative polymerase chain reaction (q-PCR), and cognitive function was evaluated by the MATRICS Consensus Cognitive Battery (MCCB). SPSS 24.0 was used for statistical analysis. Results: The telomere length of euthymic patients with BD-I and BD-II was shorter than that of healthy controls. Telomere length was not significantly different between BD-I and BD-II. Patients with BD-I and BD-II showed poor cognitive function compared to healthy controls. In the three groups, no correlation was detected with telomere length orcognitive function. The duration of illness (DI) was negatively correlated with reasoning and problem solving in BD-I. Nevertheless, the duration of untreated illness (DUI) showed a negative correlation with visual learning performance. Conclusions: This study provides preliminary evidence that shortenedtelomere length is a potential biomarker for BD-I and BD-II. However, the cognitive deficit in BD has no correlation with shortened telomere length.