Background: Common features among patients with more advanced chronic obstructive pulmonary disease (COPD) are systemic inflammation and a loss of both muscle mass and normal muscle composition. In the present study, we investigated COPD subjects to better understand how thigh muscle fat infiltration (MFI) and energy metabolism relate to each other and to clinical features of COPD with emphasis on systemic inflammation. Methods: Thirty-two Caucasians with stable COPD were investigated using questionnaires, lung function tests, blood analysis and magnetic resonance imaging (MRI) for analysis of body- and thigh muscle composition. Bioenergetics in the resting thigh muscle, expressed as the PCr/Pi ratio, were analysed using ³¹phosphorus magnetic resonance spectroscopy (³¹P-MRS). Results: Based on the combination of the MFI adjusted for sex (MFI_a) and the thigh fat-tissue free muscle volume, expressed as the deviation from the expected muscle volume of a matched virtual control group (FFMV_vcg), all COPD subjects displayed abnormally composed thigh muscles. Clinical features of increased COPD severity, including a decrease of blood oxygenation (r = − 0.44, p < 0.05) and FEV₁/FVC ratio, reflecting airway obstruction (r = − 0.53, p < 0.01) and an increase of COPD symptoms (r = 0.37, p < 0.05) and breathing frequency at rest (r = 0.41, p < 0.05), were all associated with a raise of the PCr/Pi ratio in the thigh muscle. Increased MFI_a of the thigh muscle correlated positively with markers of systemic inflammation (white blood cell count, r = 0.41, p < 0.05; fibrinogen, r = 0.44, p < 0.05), and negatively with weekly physical activity (r = − 0.40, p < 0.05) and the PCr/Pi ratio in the resting thigh muscle (r = − 0.41, p < 0.05). Conclusion: The present study implies a link between systemic inflammation, excessive MFI and a loss of bioenergetics in subjects with stable COPD.

Background: Chronic obstructive pulmonary disease (COPD) is associated with systemic inflammation and frequent exacerbations, leading to disease progression and increased morbidity. Vitamin D deficiency has been suggested to contribute to COPD inflammation and exacerbations. Aim: This study investigated the association between serum 25-hydroxyvitamin D (25(OH)D) levels, systemic inflammation, and exacerbation frequency among patients with COPD GOLD group E. Methods: A cross-sectional study was conducted on 111 patients with stable COPD. Patients were divided into two groups based on their serum 25(OH)D levels (<50 nmol/L vs. ≥50 nmol/L). Data on exacerbation frequency for the past year, inflammatory markers, spirometric lung function parameters, and symptom burden were collected. Results: Patients with low serum 25(OH)D (<50 nmol/L) had a significantly higher CAT score and level of serum high-sensitivity (hs)-CRP and exhibited significantly more exacerbations compared to those with higher 25(OH)D levels (p < 0.001, p < 0.001, and p < 0.0001, respectively). Furthermore, lower vitamin D levels were associated with higher CAT scores (Pearson’s correlation coefficient, r = −0.30, p < 0.01) and higher serum hs-CRP levels (Spearman’s rank correlation coefficient, r = −0.25, p < 0.01), as well as a higher number of exacerbations (Pearson’s correlation coefficient, r = −0.74, p < 0.0001). Conclusions: Low vitamin D levels are significantly associated with greater symptom burden, elevated hs-CRP, and increased exacerbation frequency, indicating a strong relationship between vitamin D deficiency, systemic inflammation, and disease burden in patients with COPD belonging to GOLD group E. However, due to the cross-sectional design, no causal relationship can be inferred and prospective interventional studies are required to determine whether treating vitamin D deficiency improves clinical outcomes.

Background: Chronic obstructive pulmonary disease (COPD) is associated with systemic inflammation and frequent exacerbations, thus, leading to disease progression and increased morbidity. Vitamin D deficiency has been suggested to be a contributing factor to COPD inflammation and exacerbations. Aim: To investigate the association between serum 25-hydroxyvitamin D [25(OH)D] levels, systemic inflammation and exacerbation frequency among patients with COPD GOLD group E. Methods: A cross-sectional study was conducted on 111 patients with stable COPD. Patients were divided into two groups based on their serum 25(OH)D levels (<50 nmol/L vs. ≥50 nmol/L). Data on exacerbation frequency the past year, inflammatory markers, dynamic lung volumes and symptom burden were collected. Results: Patients with low serum 25(OH)D (<50 nmol/L) had significantly higher CAT-score and level of serum-high sensitivity (hs)-CRP and exhibited significantly more exacerbations compared to those with higher levels (p < 0.001, p < 0.001 and p < 0.0001, respectively). Furthermore, lower vitamin D levels were associated with higher CAT scores (r = -0.30; p < 0.01) and level of serum hs-CRP (r = -0.25; p < 0.01) and significantly more exacerbations (r = -0.74; p < 0.0001). Conclusion: Low vitamin D levels are significantly associated with greater symptom burden, elevated hs-CRP and increased exacerbation frequency in COPD patients group E. These findings suggest that monitoring and treating vitamin D deficiency may be beneficial in COPD patients with frequent exacerbations.

BackgroundChronic obstructive pulmonary disease (COPD) is a progressive disorder with phenotypic heterogeneity, which includes nonreversible airflow limitation, chronic airway inflammation and syst ...