Serum Creatinine/Cystatin C Ratio Associated with Cross-Sectional Area of Erector Spinae Muscles and Pulmonary Function in Patients with Chronic Obstructive Pulmonary Disease

Abstract

Purpose Muscle atrophy is a major clinical feature of chronic obstructive pulmonary disease (COPD) and is considered a predictor of mortality in COPD patients. Recently, the cross-sectional area (CSA) of the erector spinae muscles measured by chest computed tomography (CT) scans (ESM CSA ) has been reported as a clinical parameter reflecting disease severity and future prognosis in patients with COPD. In addition, the serum creatinine (Cr)/cystatin C (CysC) ratio has been considered a quantitative marker of residual muscle mass, because serum Cr levels are affected by muscle mass, and correction by CysC counteracts the effect of renal function on serum Cr levels. The purpose of this study was to assess whether the serum Cr level corrected by serum CysC can be used as a predictive marker of pulmonary function and disease severity in patients with COPD. Patients and Methods A total of 99 patients without COPD and 201 patients with COPD, with a smoking history of more than 10 pack-years were enrolled in this study, and serum Cr and CysC levels were measured. On chest high-resolution CT images, %low attenuation area (LAA%) (≤960 Hounsfield units (HU)) and ESM CSA at the Th 12 level were identified. Results There was a significant correlation between the ESM CSA and the Cr/CysC ratio. The Cr/CysC ratio was significantly associated with forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1) values, especially in former smokers. Conclusion The serum Cr/CysC ratio could be a convenient substitute for the measurement of muscle atrophy and pulmonary function testing in patients with COPD.

Role of CD4+ T and CD8+ T Lymphocytes-Mediated Cellular Immunity in Pathogenesis of Chronic Obstructive Pulmonary Disease

“…Oxidative stress in lung tissue and accumulation of excess protease are both important factors that cause pulmonary inflammatory response and damage in COPD patients [ 25 ]. CysC is a major extracellular cathepsin inhibitor, which has been confirmed as an inflammatory marker of acute exacerbation [ 26 ]. CysC is absorbed and metabolized by renal tubules after glomerular filtration, and the kidney is the only organ to remove CysC.…”

Serum Derivatives of Reactive Oxygen Metabolites are Associated with Severity of Chronic Obstructive Pulmonary Disease and Affected by a p53 Gene Polymorphism

“…As expected, LAA% was significantly higher in association with impairment of pulmonary function. BMI, ESM CSA , and Cr/CysC ratio, which is an indicator of sarcopenia in COPD patients, 28–30 were decreased in patients with severe COPD compared with smoker controls. HsCRP levels were significantly increased in patients with severe COPD compared with smoker controls and patients with moderate and mild COPD ( Table 1 ).…”

“…LAA% was measured as previously reported. 25 , 27 , 28 Briefly, high-resolution computed tomography (CT) scans were acquired using a 128-multidetector CT scanner (Somatom Definition FLASH; Siemens Medical Solutions, Erlangen, Germany) with a slice thickness of 2 mm. LAA% was calculated using a threshold of −960 Hounsfield units (HU) to assess emphysematous changes and total lung volume using the computer software LungVision TM , version 2.1 (Cybernet Systems Co., Ltd., Tokyo, Japan).…”

“…The CSA of ESMs (ESM CSA ) was measured based on our previous study. 28 Briefly, ESM CSA was measured on a single-slice, axial chest CT image at the level of the lower margin of the 12th thoracic vertebra using ImageJ software (National Institutes of Health, Bethesda, MD, USA). The left and right ESMs were manually selected, the areas of both ESMs were selected, and the CSAs of both ESMs were calculated.…”

Correlation Between Bioelectrical Impedance Analysis and Chest CT-Measured Erector Spinae Muscle Area: A Cross-Sectional Study

“…First, we did not compare BIA to all skeletal muscles at the level of T12, which is also used as a measure of muscle mass. However, the ESA was selected because it is easily measurable ( 22 ) and is required for locomotion ( 37 ) and previous studies have demonstrated its application ( 9 , 38 , 39 ). Second, data were collected retrospectively, with the variables regarding the muscle strength or physical performance being unavailable.…”