Physical Activity and Respiratory Muscle Strength in Patients with Sarcoidosis: An Observational Study

Figures & data

Table 1 Characteristics of Patients with Sarcoidosis and Healthy Controls

Parameters	Patients (n = 57)	Controls (n = 50)	p-value
Age	43.56 (±12.3)	42.08 (±11.28)	0.517
Gender [male]	29 (50.9%)	23 (46%)	0.615
Height (cm)	170.28 (±9.11)	169.04 (±8.41)	0.570
Weight (kg)	73.09 (±14.77)	72.48 (±14.84)	0.967
BMI (kg/m^2)	25.27 (±4.99)	25.52 (±5.54)	0.800
Stage
Stage I - lymphadenopathy	19.3%	NA	NA
Stage II - lymphadenopathy  and pulmonary infiltrates	22.8%	NA	NA
Stage III - pulmonary infiltrates	33.3%	NA	NA
Stage IV - pulmonary fibrosis	24.6%	NA	NA

Notes: Data are presented as mean (±std. dev.) or absolute frequency (percentage).

Abbreviation: NA, not applicable.

Table 2 Results of Pulmonary Function Testing of Patients with Sarcoidosis and Healthy Controls

Tests	Patients (n = 57)	Controls (n = 50)	p-value
Spirometry
FVC (L)	3.57 (3.10–4.19)	4.03 (3.57–4.62)	0.002
FVC (%)	84.00 (78.00–90.00)	92.50 (89.00 −103.00)	<0.001
FEV1 (L)	2.85 (2.21–3.26)	3.21 (2.99–3.69)	<0.001
FEV1 (%)	80.00 (69.00–86.00)	94.00 (85.00–100.00)	<0.001
FEV1/FVC (L)	78.00 (74.00–82.00)	80.00 (77.00–87.00)	0.044
Lung volumes
TCL (L)	83.00 (71.00–91.00)	89.00 (85.00–97.00)	0.001
RV (L)	83.00 (74.00–92.00)	90.50 (83.00–97.00)	0.001
Maximal respiratory pressures
MIP (cmH2O)	87.51 (78.57–100.52)	90.99 (78.14–111.96)	0.002
MIP (%)	84.00 (79.00–91.00)	90.00 (83.00–97.00)	0.001
MEP (cmH2O)	95.46 (76.10–109.73)	92.12 (78.85–114.10)	0.009
MEP (%)	85.00 (79.00–89.00)	89.00 (85.00–92.00)	< 0.001
Diffusing capacity
DLCO (%)	20.43 (18.45–24.82)	26.13 (21.31–36.24)	<0.001
DLCOcorr (%)	84.00 (70.00–91.00)	92.50 (89.00–94.00)	<0.001
Physical activity
6MWD (m)	496.00 (437.00–550.00)	561.00 (531.00–586.00)	<0.001
6MWDpred (%)	93.00 (86.00–96.00)	97.50 (93.00–100.00)	<0.001

Notes: Data are presented as median (inter-quartile range).

Abbreviations: FEV1, forced expiratory volume in the first second; FVC, forced vital capacity; RV, residual volume; TLC, total lung capacity; MIP, maximal inspiratory pressure; MEP, maximal expiratory pressure; DLCO, diffusing capacity of lung for carbon monoxide; 6MWD, six-minute walking distance.

Figure 1 Respiratory muscle strength in patients with sarcoidosis and healthy controls.

Figure 2 Exercise capacity in patients with sarcoidosis and controls. Patients with sarcoidosis were grouped by stage.

Table 3 Health Status of Patients with Sarcoidosis

KSQ Scores	Patients (n = 57)
General Health	83.00 (76.00–88.00)
Lung Health	81.00 (73.00–86.00)
Medication	88.00 (81.00–92.00)
Skin Health	100.00 (96.00–100.00)
Eye Health	100.00 (97.00–100.00)

Notes: Data are presented as median (interquartile range).

Abbreviation: KSQ, King’s Sarcoidosis Questionnaire.

Figure 3 Association between exercise capacity and respiratory muscle strength in patients with sarcoidosis.