Peripheral Muscle Strength and Pulmonary Function Negatively Impact Functional Capacity in Patients With Post-Tuberculosis Lung Disease: A Cross-Sectional Study.

BACKGROUND AND PURPOSE: Tuberculosis primarily affects the lungs, and many patients experience sequelae, including loss of lung function and a decline in health-related quality of life (HRQoL), despite bacteriological cure. Although post-tuberculosis lung disease (PTLD) is a growing concern worldwide due to poor physical functioning, little is known about peripheral muscle dysfunction. Therefore, the objective of this study was to evaluate patient performance during the Glittre Activities of Daily Living Test (TGlittre) and assess its association with muscle function, lung function, and HRQoL.

METHODS

This cross-sectional study included 47 patients with PTLD who underwent the TGlittre. We also assessed patients for respiratory muscle strength, handgrip strength (HGS), quadriceps muscle strength (QMS), and HRQoL using the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36).

RESULTS

HGS and QMS were reduced in 34% and 25.5% of participants, respectively. Spirometry showed an obstructive pattern, a restrictive pattern, and a normal pattern in 46.8%, 31.9% and 21.3% of participants, respectively, while 42.6% of them had reduced diffusion capacity of lung for carbon monoxide (DLCO). The median TGlittre time was 4.43 (3.48-4.96) minutes, about 15% longer than the expected time to complete it. There was a significant correlation between TGlittre time and DLCO (rs = -0.532, p < 0.0002), maximum inspiratory pressure (rs = -0.407, p = 0.005), maximum expiratory pressure (rs = -0.382, p = 0.008), HGS (rs = -0.327, p = 0.024), QMS (rs = -0.314, p = 0.031), and various SF-36 domains. In the regression analysis, DLCO, QMS, and HGS explained 39% of the variability in TGlittre time.

DISCUSSION: PTLD significantly impacts functional capacity, as determined by TGlittre. These patients have muscle dysfunction, deteriorated HRQoL, and impaired lung function. Impaired lung diffusion and reduced peripheral muscle strength (PMS) are independently associated with lower functional capacity. Therefore, rehabilitative strategies are crucial for improving care for this group of patients. This is the first study using the TGlittre to explore PMS in PTLD.

TRIAL REGISTRATION: The protocol was registered on ClinicalTrials.gov with the identifier NCT06127641.