Objective: To assess the health status and fatigue in sicca patients with or without Sjögren's syndrome (SS) and to test whether the immune-inflammatory activity or the extent of the disease predict fatigue in SS.
Methods: The Medical Outcomes Study Short-Form General Health Survey (MOS SF-36) was used in 1 degree SS (n = 90), 2 degrees SS (n = 24), non-SS patients with sicca symptoms (n = 15) and healthy population controls (n = 126). Laboratory values and clinical findings were used to predict fatigue in SS.
Results: 74% of the SS and 80% of the non-SS sicca patients felt themselves tired. Vitality score values were 40.2 +/- 20.3 in 1 degree SS, 42.1 +/- 20.6 in 2 degrees SS and 29.0 +/- 15.8 in non-SS. The health profiles were similar in 1 degree and 2 degrees SS, worse (p < 0.001) than in normal controls, but in most aspects better than in non-SS sicca patients. In SS neither hemoglobin, ESR nor CRP predicted fatigue. Surprisingly, high serum IgG (p < 0.05), antinuclear antibodies (ANA) (p < 0.01) and SS-A antibodies (p < 0.05) values correlated positively with vitality. The number of disease manifestations correlated negatively with vitality (p < 0.004). The total number of disease manifestations, and ANA and/or SS-A autoantibodies were the best predictors of fatigue, but explained it only to 17-57%.
Conclusion: Patients with fatigue and perceived ill health but without fibromyalgia had sicca symptoms and low basal tear and salivary secretion rates, indicating that cortical events can lead to a SS-like sicca syndrome. Even in SS fatigue is only in part explained by clinical disease manifestations and laboratory tests assessing inflammation and autoimmunity. Fatigue in both SS and non-SS sicca syndrome more likely correlates to other features, such as neuroendocrine aspects of the disease.