Analysis of telomere length and the relationship with neurocognitive functions in euthymic bipolar disorder: A...

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.

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 38 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.

The telomere length of euthymic patients with BD-I and BD-II was shorter than that of healthy controls (F = 8.228, P = 0.001, η² = 0.176). Telomere length was not significantly different between BD-I and BD-II. Compared to HCs, poor performance was detected in attention and vigilance in BD-I patients (F = 3.473, P = 0.036). Working memory was positively correlated with telomere length in BD-II patients (Beta = 0.5, P = 0.041, Adjusted R² = 0.2).

The current study provided evidence of shortened telomere length in euthymic BD patients, indicating that telomere shortening might be a promising biomarker of susceptibility to bipolar disorder. The telomere length predicted the working memory in BD-II patients. Further studies are needed to clarify the role of accelerated aging on cognitive functioning in a young group of patients with BD.