Bipolar disorder (BD) is a chronic mental health disorder with significant morbidity and mortality. Age at onset (AAO) may be a key variable in delineating more homogeneous subgroups of BD patients. However, no known research has systematically assessed how BD age-at-onset subgroups should be defined.

中文翻译：

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双相情感障碍：三峰发病年龄分布

双相情感障碍（BD）是一种慢性精神健康障碍，具有显着的发病率和死亡率。发病年龄 (AAO) 可能是描绘更同质的 BD 患者亚组的关键变量。然而，没有已知的研究系统地评估 BD 发病年龄亚组应如何定义。