Multimorbidity is common in patients with COPD, and different comorbidity clusters can be identified. Low-grade systemic inflammation is mostly comparable among comorbidity clusters. Increasing knowledge on the interactions between comorbidities increases the understanding of their development and contributes to strategies for prevention or improved treatment.

In recent years, vitamin D has been received increased attention due to the resurgence of vitamin D deficiency and rickets in developed countries and the identification of extraskeletal effects of vitamin D, suggesting unexpected benefits of vitamin D in health and disease, beyond bone health. The possibility of extraskeletal effects of vitamin D was first noted with the discovery of the vitamin D receptor (VDR) in tissues and cells that are not involved in maintaining mineral homeostasis and bone health, including skin, placenta, pancreas, breast, prostate and colon cancer cells, and activated T cells. However, the biological significance of the expression of the VDR in different tissues is not fully understood, and the role of vitamin D in extraskeletal health has been a matter of debate. This report summarizes recent research on the roles for vitamin D in cancer, immunity and autoimmune diseases, cardiovascular and respiratory health, pregnancy, obesity, erythropoiesis, diabetes, muscle function, and aging.

The aim of the present study was to profile a multidimensional response to pulmonary rehabilitation in patients with chronic obstructive pulmonary disease (COPD).Dyspnoea, exercise performance, health status, mood status and problematic activities of daily life were assessed before and after a 40-session pulmonary rehabilitation programme in 2068 patients with COPD (mean forced expiratory volume in 1 s of 49% predicted). Patients were ordered by their overall similarity concerning their multidimensional response profile, which comprises the overall response on MRC dyspnoea grade, 6MWD, cycle endurance time, Canadian Occupational Performance Measure performance and satisfaction scores, Hospital Anxiety and Depression Scale anxiety and depression, and St George's Respiratory Questionnaire total score, using a novel non-parametric regression technique.Patients were clustered into four groups with distinct multidimensional response profiles: n=378 (18.3%; "very good responder"), n=742 (35.9%; "good responder"), n=731 (35.4%; "moderate responder"), and n=217 (10.5%; "poor responder"). Patients in the "very good responder" cluster had higher symptoms of dyspnoea, number of hospitalisations <12 months, worse exercise performance, worse performance and satisfaction scores for problematic activities of daily life, more symptoms of anxiety and depression, worse health status, and a higher proportion of patients following an inpatient PR programme compared to the other three clusters.A multidimensional response outcome needs to be considered to study the efficacy of pulmonary rehabilitation services in patients with COPD, as responses to regular outcomes are differential within patients with COPD. @ERSpublications Efficacy of pulmonary rehabilitation in patients with COPD needs to be assessed using a multidimensional response http://ow.ly/RsfYK

BackgroundEvidence regarding the efficacy of nutritional supplementation to enhance exercise training responses in COPD patients with low muscle mass is limited.The objective was to study if nutritional supplementation targeting muscle derangements enhances outcome of exercise training in COPD patients with low muscle mass.MethodsEighty‐one COPD patients with low muscle mass, admitted to out‐patient pulmonary rehabilitation, randomly received oral nutritional supplementation, enriched with leucine, vitamin D, and omega‐3 fatty acids (NUTRITION) or PLACEBO as adjunct to 4 months supervised high intensity exercise training.ResultsThe study population (51% males, aged 43–80) showed moderate airflow limitation, low diffusion capacity, normal protein intake, low plasma vitamin D, and docosahexaenoic acid. Intention‐to‐treat analysis revealed significant differences after 4 months favouring NUTRITION for body mass (mean difference ± SEM) (+15 ± 06 kg, P = 001), plasma vitamin D (+24%, P = 0004), eicosapentaenoic acid (+91%,P < 0001), docosahexaenoic acid (+31%, P < 0001), and steps/day (+24%, P = 0048). After 4 months, both groups improved skeletal muscle mass (+04 ± 01 kg, P < 0001), quadriceps muscle strength (+123 ± 23 Nm,P < 0001), and cycle endurance time (+1914 ± 343 s, P < 0001). Inspiratory muscle strength only improved in NUTRITION (+05 ± 01 kPa, P = 0001) and steps/day declined in PLACEBO (−18%,P = 0005).ConclusionsHigh intensity exercise training is effective in improving lower limb muscle strength and exercise performance in COPD patients with low muscle mass and moderate airflow obstruction. Specific nutritional supplementation had additional effects on nutritional status, inspiratory muscle strength, and physical activity compared with placebo.

Clear evidence for an association between systemic inflammation and increased arterial stiffness in patients with chronic obstructive pulmonary disease (COPD) is lacking. Moreover, the effects of pulmonary rehabilitation on arterial stiffness are not well studied.We aimed to 1) confirm increased arterial stiffness in COPD; 2) evaluate its correlates including systemic inflammation; and 3) study whether or not it is influenced by pulmonary rehabilitation.Aortic pulse-wave velocity (APWV) was determined in 168 healthy volunteers, and APWV and inflammatory markers were determined in 162 COPD patients during baseline evaluation of a pulmonary rehabilitation programme. A complete post-pulmonary rehabilitation dataset was collected in 129 patients.It was found that APWV was increased in COPD patients when compared with controls, blood pressure and age predicted baseline APWV, and systemic inflammatory markers were not independently related to APWV. Although baseline APWV was predictive for the change in APWV after pulmonary rehabilitation (r5 -0.77), on average APWV did not change (10.7¡2.7 versus 10.9¡2.5 m?s -1 ; p50.339). Arterial stiffness in COPD is not related to systemic inflammation and does not respond to state-of-theart pulmonary rehabilitation. These results emphasise the complexity of cardiovascular risk and its management in COPD. @ERSpublications Arterial stiffness in COPD is not related to systemic inflammation and does not respond to pulmonary rehabilitation