Increased neutrophil/lymphoctye ratio in patients with bipolar disorder: a preliminary study

In this study, it has been aimed to investigate whether neutrophil-lymphocyte ratio (NLR) was higher in non-obese patients with bipolar disorder (BD) than in a healthy control group matched for age, sex, and body mass index, and also to determine if there was an interaction between NLR and severity of the bipolar disorder.

In this retrospective study, 103 non-obese patients with BD and 126 healthy control subjects were analyzed for complete blood count. The Young Mania Rating Scale (YMRS) was used to determine the severity of the disorder.

The NLR was higher in female patients than in female comparison subjects (3.2±2.2; versus 1.7±0.4) (p<0.001). Also, compared with the healthy male subjects, the male patients had significantly higher neutrophil/lymphocyte ratio (3.3±2.4; versus 2.0±0.7) (p<0.001). In the patients with bipolar disorder, NLR did not significantly correlate with severity (as measured with the YMRS) (r=0.052; p=0.204) and duration of the disorder (r=0.045; p=0.301).

Results of this study revealed that patients with bipolar disorder have statistically significant elevated NRL than healthy compares. According to this finding, elevated levels of NLR may be involved in inflammatory pathophysiology of bipolar disorder. Further studies are needed for a better understanding of the mechanism between elevation of NRL in patients with bipolar disorder.