Skin condition and its relationship to systemic inflammation in chronic obstructive pulmonary disease

Background: The systemic (extrapulmonary) effects and comorbidities of chronic obstructive pulmonary disease (COPD) contribute substantially to its burden. The supposed link between COPD and its systemic effects on distal organs could be due to the low-grade systemic inflammation. The aim of this study was to investigate whether the systemic inflammation may influence the skin condition in COPD patients. Materials and methods: Forty patients with confirmed diagnosis of COPD and a control group consisting of 30 healthy smokers and 20 healthy never-smokers were studied. Transepidermal water loss, stratum corneum hydration, skin sebum content, melanin index, erythema index, and skin temperature were measured with worldwide-acknowledged biophysical measuring methods at the volar forearm of all participants using a multifunctional skin physiology monitor. Biomarkers of systemic inflammation, including high-sensitivity C-reactive protein (hsCRP), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-alpha), were measured in serum using commercially available enzyme-linked immunosorbent assays. Results: There were significant differences between COPD patients and healthy never-smokers in skin temperature, melanin index, sebum content, and hydration level (P<0.05), but not for transepidermal water loss and erythema index. No significant difference was noted between COPD patients and smokers in any of the biophysical properties of the skin measured. The mean levels of hsCRP and IL-6 in serum were significantly higher in COPD patients and healthy smokers in comparison with healthy never-smokers. There were significant correlations between skin temperature and serum hsCRP (R=0.40; P=0.02) as well as skin temperature and serum IL-6 (R=0.49; P=0.005) in smokers. Stratum corneum hydration correlated significantly with serum TNF-alpha (R=0.37; P=0.01) in COPD patients. Conclusion: Differences noted in several skin biophysical properties and biomarkers of systemic inflammation between COPD patients, smokers, and healthy never-smokers may suggest a possible link between smoking-driven, low-grade systemic inflammation, and the overall skin condition.