[Peculiarities of sarcopenia in occupational chronic obstructive pulmonary disease in conditions of exposure of industrial aerosols containing nanoparticles].

BACKGROUND

The influence of nanoparticles of industrial aerosols on phenotypes of occupational chronic obstructive pulmonary disease (COPD) is not studied enough. In this connection the system signs and symptoms of the disease including sarcopenia is of a great interest for investigation, because there associations with quality of life and lifespan.

AIM: To establish the features of sarcopenia in patients with COPD due to aerosols containing nanoparticles.

MATERIALS AND

METHODS

A prospective observational study was performed. Previously, chemical and hygienic investigation of nanoparticles in the workplaces air on the machine building enterprise was done. The groups under investigation were occupational COPD patients, who were employed at the workplaces that has been investigated and contacting with aerosols containing metal (n = 48) or silica (n = 55) nanoparticles. Groups were matched by sex, age, COPD duration. Study procedures were Sarcopenia Fast questionnaire, ultrasound measurement of quadriceps femoris, bioelectrical impedance analysis, hand grip strength by dynamometry, sit-to-stand test, short physical performance battery, pulmonary function tests, serum molecular markers measured by enzyme-linked immunosorbent assay or by kinetic method, serum fibrinogen by Klauss method. COPD was diagnosed when postbronchodilator forced expiratory volume in one second divided by forced vital capacity was less than 0.7. Sarcopenia was diagnosed by EWGSOP2 criteria (European Working Group on Sarcopenia in Older People). Statistical analysis included descriptive methods and liner regression.

RESULTS

Sarcopenia rate was 26 (47.2%) in COPD due to aerosols containing silica nanoparticles, 17 (35.4%) in COPD due to aerosols containing metal nanoparticles and 15 (30.0%) in control group; p = 0.015. The differences of sarcopenia severity between COPD due to different environmental conditions were seen - Ме (Q2-Q3). COPD due to aerosols containing silica nanoparticles was characterized by minimal values of quadriceps cross-sectional area: 4.9 (4.0-5.5) sm2 compared with 9.4 (8.4-9.9) sm2 in COPD due to aerosols containing metal nanoparticles patients and with 9,0 (7.8; 9.2) sm2 in control group respectivel; р = 0.010, quadriceps thickness, appendicular fat-free mass index: 7.1 (5.5-7.4), 7.5 (6.2-8.3) and 8.2 (6.8-9.1) kg/m2; р = 0.009, sit-to-stand test 15.8 (13.2-16.7), 12.1 (10.5-13.0) and 11.5 (9.4-13.8) s; р = 0.009, by elevated muscle echogenicity. COPD due to aerosols containing metal nanoparticles patients had the mid values. After 12 months these relationships were preserved. The associations of silica nanoparticles with quadriceps cross-sectional area (В = -0.95; р = 0.009), echogenicity (В = 1.02; р = 0.001), appendicular fat-free mass index (В = -1.05; р = 0.001) and sit-to-stand test (В = 0.91; р = 0.011) were explored.

CONCLUSION

Occuational COPD is characterized by sarcopenia rate, less values of muscle quantity and quality, especially pronounced in COPD due to aerosols containing silica nanoparticles.