Lower Prevalence of Osteoporosis in Patients with COPD Taking Anti-Inflammatory Compounds for the Treatment of Diabetes: Results from COSYCONET

Midregional Proatrial Natriuretic Peptide (MRproANP) is associated with vertebral fractures and low bone density in patients with chronic obstructive pulmonary disease (COPD)

BACKGROUND

Patients with COPD are often affected by loss of bone mineral density (BMD) and osteoporotic fractures. Natriuretic peptides (NP) are known as cardiac markers, but have also been linked to fragility-associated fractures in the elderly. As their functions include regulation of fluid and mineral balance, they also might affect bone metabolism, particularly in systemic disorders such as COPD.

RESEARCH QUESTION

We investigated the association between NP serum levels, vertebral fractures and BMD assessed by chest computed tomography (CT) in patients with COPD.

METHODS

Participants of the COSYCONET cohort with CT scans were included. Mean vertebral bone density on CT (BMD-CT) as a risk factor for osteoporosis was assessed at the level of TH12 (AI-Rad Companion), and vertebral compression fractures were visually quantified by two readers. Their relationship with N-terminal pro-B-type natriuretic peptide (NT-proBNP), Mid-regional pro-atrial natriuretic peptide (MRproANP) and Midregional pro-adrenomedullin (MRproADM) was determined using group comparisons and multivariable analyses.

RESULTS

Among 418 participants (58% male, median age 64 years, FEV1 59.6% predicted), vertebral fractures in TH12 were found in 76 patients (18.1%). Compared to patients without fractures, these had elevated serum levels (p ≤ 0.005) of MRproANP and MRproADM. Using optimal cut-off values in multiple logistic regression analyses, MRproANP levels ≥ 65 nmol/l (OR 2.34; p = 0.011) and age (p = 0.009) were the only significant predictors of fractures after adjustment for sex, BMI, smoking status, FEV1% predicted, SGRQ Activity score, daily physical activity, oral corticosteroids, the diagnosis of cardiac disease, and renal impairment. Correspondingly, MRproANP (p < 0.001), age (p = 0.055), SGRQ Activity score (p = 0.061) and active smoking (p = 0.025) were associated with TH12 vertebral density.

INTERPRETATION

MRproANP was a marker for osteoporotic vertebral fractures in our COPD patients from the COSYCONET cohort. Its association with reduced vertebral BMD on CT and its known modulating effects on fluid and ion balance are suggestive of direct effects on bone mineralization.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01245933, Date of registration: 18 November 2010.

Expiratory Venous Volume and Arterial Tortuosity are Associated with Disease Severity and Mortality Risk in Patients with COPD: Results from COSYCONET

Purpose

The aim of this study was to evaluate the association between computed tomography (CT) quantitative pulmonary vessel morphology and lung function, disease severity, and mortality risk in patients with chronic obstructive pulmonary disease (COPD).

Patients and Methods

Participants of the prospective nationwide COSYCONET cohort study with paired inspiratory-expiratory CT were included. Fully automatic software, developed in-house, segmented arterial and venous pulmonary vessels and quantified volume and tortuosity on inspiratory and expiratory scans. The association between vessel volume normalised to lung volume and tortuosity versus lung function (forced expiratory volume in 1 sec [FEV1]), air trapping (residual volume to total lung capacity ratio [RV/TLC]), transfer factor for carbon monoxide (TLCO), disease severity in terms of Global Initiative for Chronic Obstructive Lung Disease (GOLD) group D, and mortality were analysed by linear, logistic or Cox proportional hazard regression.

Results

Complete data were available from 138 patients (39% female, mean age 65 years). FEV1, RV/TLC and TLCO, all as % predicted, were significantly (p < 0.05 each) associated with expiratory vessel characteristics, predominantly venous volume and arterial tortuosity. Associations with inspiratory vessel characteristics were absent or negligible. The patterns were similar for relationships between GOLD D and mortality with vessel characteristics. Expiratory venous volume was an independent predictor of mortality, in addition to FEV1.

Conclusion

By using automated software in patients with COPD, clinically relevant information on pulmonary vasculature can be extracted from expiratory CT scans (although not inspiratory scans); in particular, expiratory pulmonary venous volume predicted mortality.

Trial Registration

NCT01245933.

COPD and multimorbidity: recognising and addressing a syndemic occurrence

Most patients with chronic obstructive pulmonary disease (COPD) have at least one additional, clinically relevant chronic disease. Those with the most severe airflow obstruction will die from respiratory failure, but most patients with COPD die from non-respiratory disorders, particularly cardiovascular diseases and cancer. As many chronic diseases have shared risk factors (eg, ageing, smoking, pollution, inactivity, and poverty), we argue that a shift from the current paradigm in which COPD is considered as a single disease with comorbidities, to one in which COPD is considered as part of a multimorbid state-with co-occurring diseases potentially sharing pathobiological mechanisms-is needed to advance disease prevention, diagnosis, and management. The term syndemics is used to describe the co-occurrence of diseases with shared mechanisms and risk factors, a novel concept that we propose helps to explain the clustering of certain morbidities in patients diagnosed with COPD. A syndemics approach to understanding COPD could have important clinical implications, in which the complex disease presentations in these patients are addressed through proactive diagnosis, assessment of severity, and integrated management of the COPD multimorbid state, with a patient-centred rather than a single-disease approach.

Jörres R, Behr J, Welte T. The Diagnosis and Treatment of COPD and Its Comorbidities

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is the third most common cause of death around the world. The affected patients suffer not only from impaired lung function, but also from a wide variety of comorbidities. Their cardiac comorbidities, in particular, lead to increased mortality.

METHODS

This review is based on pertinent publications retrieved by a selective search in PubMed, including guidelines from Germany and abroad.

RESULTS

The usual diagnostic criteria for COPD are a post-bronchodilator FEV1/FVC quotient below the fixed threshold of 0.7, or, preferably, below the lower limit of normal (LLN) according to the GLI reference values for the avoidance of over- and underdiagnosis. The overall prognosis is markedly affected by comorbidities of the lung itself and those that involve other organs; in particular, many persons with COPD die of heart disease. The potential presence of heart disease must be borne in mind in the evaluation of patients with COPD, as lung disease can impair the detection of heart disease.

CONCLUSION

As patients with COPD are often multimorbid, the early diagnosis and adequate treatment not only of their lung disease, but also of their extrapulmonary comorbidities are very important. Well-established diagnostic instruments and well-tested treatments are available and are described in detail in the guidelines concerning the comorbidities. Preliminary observations suggest that more attention should be paid to the potential positive effects of treating comorbidities on the lung disease itself, and vice versa.

[What have we learned from the German COPD cohort COSYCONET and where do we go from here?]

COSYCONET 1 is the only German COPD cohort which is large enough to be internationally comparable. The recruitment, which started in 2010 and ended in December 2013, comprised 2741 patients with the diagnosis of COPD who were subsequently investigated in regular follow-up visits. All visits included a comprehensive functional and clinical characterisation. On the basis of this detailed data set, it was possible to address a large number of clinical questions. These questions ranged from the prescription of medication, the detailed analysis of comorbidities, in particular cardiovascular disease, and biomarker assessment to radiological and health-economic aspects. Currently, more than 60 publications of COSYCONET data are internationally available. The present overview provides a description of all the results that were obtained, focussing on the relationship between different clinical and functional aspects as well as their potential practical consequences. In addition, information on the follow-up study COSYCONET 2 is given.

Mechanisms Linking COPD to Type 1 and 2 Diabetes Mellitus: Is There a Relationship between Diabetes and COPD?

Chronic obstructive pulmonary disease (COPD) patients frequently suffer from multiple comorbidities, resulting in poor outcomes for these patients. Diabetes is observed at a higher frequency in COPD patients than in the general population. Both type 1 and 2 diabetes mellitus are associated with pulmonary complications, and similar therapeutic strategies are proposed to treat these conditions. Epidemiological studies and disease models have increased our knowledge of these clinical associations. Several recent genome-wide association studies have identified positive genetic correlations between lung function and obesity, possibly due to alterations in genes linked to cell proliferation; embryo, skeletal, and tissue development; and regulation of gene expression. These studies suggest that genetic predisposition, in addition to weight gain, can influence lung function. Cigarette smoke exposure can also influence the differential methylation of CpG sites in genes linked to diabetes and COPD, and smoke-related single nucleotide polymorphisms are associated with resting heart rate and coronary artery disease. Despite the vast literature on clinical disease association, little direct mechanistic evidence is currently available demonstrating that either disease influences the progression of the other, but common pharmacological approaches could slow the progression of these diseases. Here, we review the clinical and scientific literature to discuss whether mechanisms beyond preexisting conditions, lifestyle, and weight gain contribute to the development of COPD associated with diabetes. Specifically, we outline environmental and genetic confounders linked with these diseases.

Metformin treatment is associated with an increase in bone mineral density in type 2 diabetes mellitus patients in China: a retrospective single center study

AIMS

- To investigate the association between metformin and bone mineral density (BMD) in a large cohort of Chinese patients with type 2 diabetes mellitus (T2DM).

METHODS

- A total of 11,458 T2DM patients aged ≥ 40 years were included. Information on demographic, anthropometric and clinical characteristics was collected from medical records. BMD at lumbar spine (LS), femoral neck (FN), and total hip(TH) was assessed by dual-energy X-ray absorptiometry.

RESULTS

- Overall prevalence of osteopenia and osteoporosis was 37.4% and 10.3%, and was lower in patients on metformin (34.6% vs 38.3% and 7.1% vs 11.3%, both P < 0.001). Patients who had a lower BMI, older age, and lower estimated glomerular filtration rate (eGFR), had more osteoporosis, lower BMD (osteoporosis or osteopenia), and a lower T-score at LS, FN and TH. Metformin use and male sex was associated with a higher BMD. Metformin treatment was also independently associated with higher T-score at LS, FN and TH (β values of 0.120, 0.082 and 0.108; all P < 0.001), and lower odds ratio of osteoporosis (OR = 0.779, 95%CI: 0.648-0.937, P = 0.008) or low BMD (OR = 0.834, 95%CI: 0.752 - 0.925, P = 0.001). However, when analyzed by sex, this association of a lower odds ratio for osteoporosis with metformin was only significant in women (OR= 0.775, 95% CI: 0.633-0.948; P = 0.013).

CONCLUSIONS

- Metformin treatment was associated with a higher T-score and a lower odds ratio of osteopenia and osteoporosis, especially in the female population, independent of age, BMI, and eGFR.