Bipolar disorder is often comorbid with anxiety, which is itself associated with poorer clinical outcomes, including suicide. A better etiologic understanding of this comorbidity could inform diagnosis and treatment. The present study aims to test whether comorbid anxiety in bipolar disorder reflects shared genetic risk factors. We also sought to assess the contribution of genetic risk for anxiety to suicide attempts in bipolar disorder. Polygenic risk scores (PRS) were calculated from published genome-wide association studies of samples of controls and cases with anxiety (n = 83,566) or bipolar disorder (n = 51,710), then scored in independent target samples (total n = 3369) of individuals with bipolar disorder who reported or denied lifetime anxiety disorders or suicidal attempts in research interviews. Participants were recruited from clinical and nonclinical settings and genotyped for common genetic variants. The results show that polygenic risk for anxiety was associated with comorbid anxiety disorders and suicide attempts in bipolar disorder, while polygenic risk for bipolar disorder was not associated with any of these variables. Our findings point out that comorbid anxiety disorders in bipolar disorder reflect a dual burden of bipolar and anxiety-related genes; the latter may also contribute to suicide attempts. Clinical care that recognizes and addresses this dual burden may help improve outcomes in people living with comorbid bipolar and anxiety disorders.

双相情感障碍通常与焦虑症并存，焦虑症本身与较差的临床结果（包括自杀）有关。对这种合并症有更好的病因学理解可以为诊断和治疗提供依据。本研究旨在检验双相情感障碍的合并症焦虑症是否反映了共同的遗传危险因素。我们还试图评估遗传风险对双相情感障碍自杀未遂的影响。多基因风险评分（PRS）是根据已发表的对照组和患有焦虑症（n  = 83,566）或双相情感障碍（n  = 51,710）的病例样本的全基因组关联研究计算的，然后在独立的目标样本中评分（总n = 3369）患有双相情感障碍的个体，他们在研究访谈中报告或否认了终生焦虑症或自杀企图。从临床和非临床环境中招募参与者，并对常见的遗传变异进行基因分型。结果表明，双相情感障碍的多基因风险与合并症焦虑症和自杀未遂相关，而双相情感障碍的多基因风险与这些变量均不相关。我们的研究结果指出，双相情感障碍的合并症焦虑症反映了双相情感障碍和焦虑相关基因的双重负担。后者也可能助长自杀企图。认识到并解决这种双重负担的临床护理可能有助于改善合并双相情感障碍和焦虑症患者的预后。