A chronic disease or long-term medical condition; an ailment someone has had for a long time.
彼は持病の喘息で運動を控えている。
He refrains from exercising because of his chronic asthma.
持病がある場合は旅行前に医師に相談したほうがいい。
If you have a chronic condition, you should consult a doctor before traveling.
その薬は持病の症状を和らげるために処方された。
That medicine was prescribed to alleviate symptoms of the chronic illness.
Figuratively, an intractable habit or longstanding tendency (e.g., 'his chronic lateness'); a bad habit that persists.
彼の遅刻は持病のようで、何度注意しても直らない。
His lateness is like a chronic condition; no matter how often you warn him, it doesn't change.
甘いもの好きは私の持病だ。
My love of sweets is my bad habit that's hard to break.
仕事中の集中力の欠如が持病になっていると本人が言った。
He said that lack of concentration at work has become a chronic problem for him.