The correlation between symptoms and spirometry in patients presenting with smoking-related symptoms

Background: the presence of chronic productive cough seems to be an independent risk factor for the development of chronic obstructive pulmonary disease (COPD) in current smokers. Stage 0 disease, or sub-clinical COPD, correlates with the risk of further developing COPD. Spirometry is indicated when a person presents with respiratory symptoms. The aim of this study was to investigate the correlation between spirometry and symptoms in a group of current smokers. Methods: thirty eight men and twenty women known as current smokers and presenting with respiratory symptoms were recruited. Respiratory symptoms were: dyspnea, chronic productive cough, and wheezing. A non-smokers control group was also recruited, age and sex matched. Impaired respiratory function, correlated with obstructive lung disease, as stated in current guidelines, was defined as FEV1/VC ratio <;0.70. The results were analyzed using SPSS 10 for Windows; data are reported as mean, standard deviations and standard errors. The statistical significance was given by a p value <;0.05. Results: from the total of fifty eight patients with respiratory symptoms, 55% had spirometric changes (FEV 1/VC ratio <;0.70). Lower age, female gender, higher body mass index (BMI) and smoking index were related to significant respiratory symptoms despite an FEV (1)/VC ratio of >/=0.70. The most common problem in the quality assessment was an insufficient exhalation time. There were statistically significant differences (p <; 0.05) between men and women in our group regarding the correlation between symptoms and spirometry, especially when it comes to chronic cough and dyspnea, women having more often normal spirometric results, with mild or moderate symptoms. Conclusions: Half of our group of current smokers with symptoms had their suspected diagnosis confirmed with spirometry. Our data indicate that female gender, smoking index, higher BMI and shorter exhalation time increase the risk of being diagnosed with COPD without fulfilling the spirometric criteria for the disease. On the other hand, smokers who complain of this symptom should be regarded as being at high risk for the development of COPD, and should be closely monitorized. Patients with smoking-related symptoms should be offered spirometry as they may benefit from symptom-relieving treatment.