Background:COPD and asthma are obstructive lung diseases associated with increased mortality. Previous studies found higher advanced glycation end products (AGEs) levels in lung, plasma and skin of COPD patients.

Aims and objectives:To investigate whether AGEs level is associated with COPD or asthma prevalence and how smoking might involve in it.

Methods:In 2577 participants of the Rotterdam Study (613 prevalent COPD, 215 prevalent asthma), AGEs were measured by skin autofluorescence (SAF) using the AGE Reader^TM. FEV₁ and diffusing capacity of the lung (D_LCOc and D_LCOc /alveolar volume [V_A]) were measured and adjusted by hemoglobin. The associations of SAF with COPD and asthma prevalence, GOLD stage, lung function were analyzed cross-sectionally in logistic/linear regression models adjusted by potential covariates, followed by interaction and stratified analyses for COPD and smoking.

Results:SAF was associated with COPD prevalence (OR=1.299 [95% CI 1.060-1.591]) but the association was not significant after adjusting for smoking status (OR=1.106 [0.897-1.363]). SAF was associated with FEV1%predicted, D_LCOc (?=-3.384 & ?= -0.212); GOLD stage (OR=4.073, stage 3&4 versus 1).The association between SAF and FEV₁%predicted was much stronger in COPD participants (?=-6.362) than in non-COPD participants (?=-1.712). This association was also confined to former smokers(?=-4.567). No significant result for asthma was found.   

Conclusions:Associations between SAF, lung function and COPD were strongly influenced by smoking status. The effect of SAF on lung function was more prominent in COPD patients. Further research into interrelations and causality between SAF, smoking and COPD are needed.