Last reviewed 01/2018
There is a striking association with smoking but a causal relationship has yet to be demonstrated. Current belief is that the disease is caused by an immunologic process initiated in response to smoking and other factors.
Socio-economic group may be important since many patients come from poor backgrounds with inadequate hygiene and a history of chronic fungal infection. Genetic factors are suggested by the fact that blacks are rarely affected whereas the disease is common in Asia. Autonomic overactivity is suggested by the association with severe peripheral vasospasm and hyperhidrosis. Familial predisposition has also been reported.