Paraseptal emphysema: Prevalence and distribution on CT and association with interstitial lung abnormalities

Abstract

Objective To investigate the prevalence and distribution of paraseptal emphysema on chest CT images in the Framingham Heart Study (FHS) population, and assess its impact on pulmonary function. Also pursued was the association with interstitial lung abnormalities. Materials and Methods We assessed 2633 participants in the FHS for paraseptal emphysema on chest CT. Characteristics of participants, including age, sex, smoking status, clinical symptoms, and results of pulmonary function tests, were compared between those with and without paraseptal emphysema. The association between paraseptal emphysema and interstitial lung abnormalities was investigated. Results Of the 2633 participants, 86 (3%) had pure paraseptal emphysema (defined as paraseptal emphysema with no other subtypes of emphysema other than paraseptal emphysema or a very few centrilobular emphysema involved) in at least one lung zone. The upper zone of the lungs was almost always involved. Compared to the participants without paraseptal emphysema, those with pure paraseptal emphysema were significantly older, and were more frequently male and smokers (mean 64 years, 71% male, mean 36 pack-years, p<0.001) and had significantly decreased FEV1/FVC% (p=0.002), and diffusion capacity of carbon monoxide (DLCO) (p=0.002). There was a significant association between pure paraseptal emphysema and interstitial lung abnormalities (p<0.001). Conclusions The prevalence of pure paraseptal emphysema was 3% in the FHS population, predominantly affects the upper lung zone, and contributes to decreased pulmonary function. Cigarette smoking, aging, and male gender were the factors associated with the presence of paraseptal emphysema. Significant association between paraseptal emphysema and interstitial lung abnormalities was observed.

Pulmonary cysts identified on chest CT: are they part of aging change or of clinical significance?

“…In the previous studies, it was not possible to discuss the association between age-related pulmonary cysts and emphysema because the presence of chronic lung diseases including emphysema was a part of exclusion criteria 3 4 6 17. Furthermore, some other findings also bolster the fact that pulmonary cysts are a distinct entity from emphysema: pulmonary cysts are not associated with smoking and tend to occur with the lower lobe predilection with no sex difference and no impairment of measures of spirometry, whereas emphysema predominantly occurs in the upper lobes, in male smokers 18. However, there might be possible overlaps on CT findings between these two entities because compressed lung parenchyma adjacent to emphysematous lesions may show increased density, mimicking the thin wall of pulmonary cysts, which probably represent atelectasis or interlobular septa 19.…”

Automated computed tomography quantification of fibrosis predicts prognosis in combined pulmonary fibrosis and emphysema in a real-world setting-A single-centre, retrospective study

“…In the Cox regression analysis, we considered the following factors: age, sex, and amount of cigarette smoking, which were previously reported to be associated with emphysema, interstitial lung abnormality, and disease progression by a subanalysis of the Framingham Heart Study [11,22]. The CCI [12] was also included in the regression analysis.…”

Pulmonary hypertension in combined pulmonary fibrosis and emphysema: A tale of two cities

“…In a handful of studies where emphysema subtypes were evaluated, paraseptal emphysema was associated with a worse prognosis compared with the other subtypes . Interestingly, in the Framingham Heart Study, 3% (86/2633) of the study population had pure paraseptal emphysema and these changes were predominantly located in the upper zones. Cigarette smoking, ageing and male gender were associated with the presence of paraseptal emphysema.…”