Abstract
Background We have previously reported that early exposure to tobacco smoke significantly increases the prevalence of chronic obstructive pulmonary disease (COPD). As a follow-up, we hypothesized that COPD arising from early exposure to tobacco smoke may increase intima media thickness (IMT), which correlates with an increased prevalence of smoke-related vascular comorbidities such as cardiovascular and cerebrovascular diseases.
Methods This prospective, observational study of a consecutive cohort of COPD patients was carried out between 2009 and 2013. Potential subjects were identified from the Erimo town clinic and were divided into three groups: Group (1) had a history of COPD and early exposure to tobacco smoke; Group (2) had a history of COPD and non-early exposure to tobacco smoke; and Group (3) included subjects without COPD. The IMT of members of all 3 groups was measured by ultrasonography using the longitudinal axis of the common carotid arteries. Early smoke exposure was defined as habitual smoking starting before age 20.
Results A total of 152 subjects (mean age 72 ± 10 years) were enrolled in the study after providing their informed consent. Groups 1, 2, and 3 consisted of 41 subjects (mean age 68 ± 9), 80 subjects (mean age 71 ± 11), and 31 subjects (mean age 69 ± 10), respectively. The maximum IMT value in Groups 1, 2, and 3 was 1.62 ± 0.35 mm, 1.46 ± 0.43 mm, and 1.32 ± 0.26 mm, respectively. Groups with a history of COPD tended to have higher maximum IMT values that the group without COPD. Furthermore, Group 1 had the highest IMT value.
Conclusion In subjects with COPD, early smoke exposure promoted atherosclerotic changes, which may have increased the likelihood of smoke-related vascular comorbidities such as cardiovascular and cerebrovascular diseases. Further studies are needed to elucidate the precise magnitude of the increased risk of these comorbidities associated with COPD and early smoke exposure.
