Physical activity in patients with sarcoidosis

Background: Little is known about physical activity in daily life in patients with sarcoidosis. Fatigue is a frequent and disabling symptom that might negatively affect physical activity levels. Methods: In patients with sarcoidosis we measured physical activity (steps per day, SPD) by accelerometry (SenseWear Armband) for one week. We assessed lung function (DLCO, FVC), exercise capacity (6-min walk-distance, 6MWD), health-related quality of life (SGRQ), generic quality of life (SF-12), and fatigue (MFI-20). Results: We investigated 57 patients with sarcoidosis (mean age 50 years, 56% male, mean DLCO 73%pred., mean FVC 91%pred., mean 6MWD 525m, mean SPD 7,490) of whom n=14 (25%) had severe fatigue. MFI-20 subscales ‘reduced activity’ and ‘physical fatigue’ were weakly associated with SPD on a bivariate level (Spearman-rho=-0.27, and -0.28; p Conclusion: While exercise capacity and quality of life measurements were robust predictors of physical activity in patients with sarcoidosis, associations of objectively measured physical activity with fatigue were surprisingly weak. In sarcoidosis, fatigue might not preclude affected patients from being physically active, although this symptom is subjectively perceived as highly disabling.