Physical capacity in women with primary Sjögren's syndrome: a controlled study

To examine physical capacity (aerobic capacity, joint mobility, muscle function, and standing balance) in women with primary Sjögren's syndrome (primary SS) and to examine the correlation of aerobic capacity with fatigue, functional disability, and mental aspects (anxiety and depression).

Fifty-one women who fulfilled the European Community criteria for primary SS and who had anti-SSA/SSB antibodies or a positive lip biopsy were compared with 51 age-matched controls. Physical capacity, fatigue, functional disability, anxiety, and depression were investigated by means of questionnaires and clinical examinations.

The women with primary SS had significantly decreased aerobic capacity (VO(2max) = 28.7 versus 32.4 ml/kg/minute; P = 0.013), shoulder mobility (58 versus 59 scale points; P = 0.003), grip strength (214 versus 259 N; P = 0.000), isokinetic strength of the knee flexors (51 versus 56 Nm; P = 0.049), endurance of the knee flexors (620 versus 712 J; P = 0.008), and standing balance (25 versus 28 seconds; P = 0.006) when compared with the reference group. For the primary SS patients, greater effort was needed to carry out the test of aerobic capacity, and they experienced more pain during the shoulder mobility test. Aerobic capacity correlated with the fatigue experienced (r = -0.33, P = 0.022) but not with functional disability or mental aspects.

The results indicate that women with primary SS have decreased physical capacity, which may be related to the experience of fatigue.