I smoked for 42 years and have been diagnosed with COPD with a FEV1 of 67%. I know COPD does damage that cannot be reversed but reading the affects of quitting smoking improved lung function of up to 30% within 9 months is one of the benefits. While I would not expect to see imnprovements of 30% because of the existing damage but one would think there should be improvement and just wondered if that would be reflected in the FEV1, and what type of improvement is generally expected.
Thank you.