Background In patients with SLE, subjective parameters are very important as they have a great impact on the quality of life. Among them, fatigue is the most prevalent symptom in SLE, as it occurs in more than 90% of patients (1). Likewise, approximately 50% of patients consider fatigue the most disabling symptom of the disease (2). Despite its high prevalence and impact on quality of life, fatigue has not been extensively studied in patients with SLE.
Objectives To determine the prevalence of fatigue in our cohort as well as the factors with which it is associated, its relationship with demographic variables, vitamin D levels, treatments, SLE symptoms and disease activity.
Methods A cross-sectional study was carried out including female patients with SLE (ACR 1997 criteria) who regularly attended the Parc de Salut Mar-IMAS in Barcelona between January 2012 and May 2014. We collected sociodemographic data, vitamin D supplementation, the VAS fatigue, pharmacological treatment, main serological markers of SLE, and plasma levels of 25-hydroxy vitamin D. The association between fatigue and the different variables was evaluated by the Spearman's rho correlation coefficient for the continuous and the Mann-Whitney U test for the categorical variables.
Results One hundred and two consecutive female patients were included. The fatigue variable was evaluated through a fatigue VAS with a mean score of 52.84 (range 0–100), a median of 59.00 and a standard deviation of 29.86. A statistically significant relationship was found between fatigue and age, MHAQ, SLICC and photosensitivity in the entirety of the 102 patients. As for the relationship between fatigue and vitamin D insufficiency (25-OH vit. D≤30 levels), the sample was divided into patients receiving vitamin D supplementation (N=60) and without supplementation (N=40), finding a significant relationship between fatigue and vitamin D insufficiency in the group without supplementation.
Conclusions Fatigue is highly prevalent among female patients with SLE. A statistically significant association was found between the presence of fatigue, on the one hand, and age, MHAQ, SLICC, photosensitivity, and vitamin D insufficiency in the group of patients without supplementation on the other. It is necessary to carry out further studies with a larger sample and with validated fatigue measurement scales to confirm our findings.
Zonana-Nacach, A., Roseman, J. M., McGwin, G., Friedman, A. W., Baethge, B. A., Reveille, J. D., et al., and the LUMINA Study Group. Systemic lupus erythematosus in three ethnic groups. VI. Factors associated with fatigue within 5 years of criteria diagnosis. Lupus 2000; 9: 101–9.
Krupp, L. B., LaRocca, N. G., Muir-Nash, J., Steinberg, A. D. The fatigue severity scale: application to patients with multiple sclerosis and systemic lupus erythematosus. Arch. Neurol. 1989; 46: 1121–3.
Disclosure of Interest None declared