TITLE:
Pulmonary rehabilitation outcome of exercise-induced oxygen desaturation in systemic sclerosis with interstitial lung disease
AUTHORS:
Fujiko Someya, Naoki Mugii
KEYWORDS:
Systemic Sclerosis; Interstitial Lung Disease; Training; Oxygen Saturation; Exercise Capacity
JOURNAL NAME:
Health,
Vol.5 No.6B,
June
17,
2013
ABSTRACT: While exercise capacity in systemic
sclerosis with interstitial lung disease could be improved by exercise training,
the training outcome of exercise-induced
oxygen desaturation has not been examined. The aim of this study was to
investigate the effect of pulmonary rehabilitation on exercise-induced oxygen
desaturation during the six-minute walk test and to detect the factors affecting
outcome retrospectively. Patients showing impaired exercise capacity (≤80% of
predicted) and/or exercise-induced oxygen desaturation (≤-4% in SpO2) at the end of the six-minute walk
test underwent routine walking exercise. Sixteen patients with stable systemic
sclerosis completed exercise training for 55 days on average. The mean
six-minute walk distance improved from 467 m to 502 m (P = 0.0012). The improvement in distance was negatively related to
baseline distance (R2 = 0.28, P = 0.037), but was not related to
parameters from pulmonary function tests and echocardiograms. Oxygen saturation
was normal at rest, but was decreased in fifteen patients at the end of the
test. Exercise-induced oxygen desaturation was positively related to the diffusion
capacity of the lungs for carbon monoxide at baseline (R2 = 0.33, P =
0.026); however, it was not related to any cardiopulmonary parameters after
intervention. Seven of sixteen patients ameliorated exercise-induced oxygen
desaturation or showed no oxygen desaturation after exercise training, while
others deteriorated. No cardiopulmonary parameters affected the training
outcome of exercise-induced oxygen desaturation. Exercise train ing was
beneficial in improving exercise tolerance, but training effects and mechanisms
on exercise-induced oxygen desaturation still need more studies to be explained.