Clubbed fingers – where the tips become bulbous and nails curve downward – can be a subtle sign of underlying disease. They can be associated with low oxygen levels in the blood over time.
While heart disease is one possible cause, particularly congenital heart defects or infective endocarditis, clubbing is more commonly linked to lung conditions such as bronchiectasis, pulmonary fibrosis or lung cancer.
Clubbed fingers can occasionally be normal for some people – it can run in families and cause no health issues at all.
That said, clubbing is more often associated with serious conditions like heart or lung disease, so it’s important not to assume it’s harmless without a medical assessment.
This article is an answer to the question (asked by James Clarke, via email) 'What do clubbed fingers mean?'
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