{'fraction_non_alphanumeric': 0.040584415584415584, 'fraction_numerical': 0.023809523809523808, 'mean_word_length': 5.465034965034965, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Prevalence and Factors Associated with Headache in Patients with Systemic Lupus Erythematosus

Headache is common in systemic lupus erythematosus with reported prevalence as high as 70%. The aims of this study were: to estimate the prevalence and types of headache in a sample of patients with systemic lupus erythematosus comparing it with rheumatoid arthritis, to determine clinical and serological associations. Eighty-one systemic lupus erythematosus and 29 rheumatoid arthritis consecutive patients seen in our outpatient clinic were interviewed. Headache was evaluated using the diagnostic criteria proposed by the International Headache Society. Additional evaluations were carried out in the 81 systemic lupus erythematosus patients including depression, disease activity, lupus damage, function disability, quality of life, and severity degree using a validated scales. We analysed the following autoantibodies: anti-double stranded DNA, anti-nucleosomes, anti-histones, anti-ribosomal P, anti-cardiolipin antibodies, anti-β2-glycoprotein-I (GPI), and antinuclear antibodies. Forty-one per cent of systemic lupus erythematosus and 17% of rheumatoid arthritis patients suffered from headache (P = 0.02). No significant difference for any primary headache type between the two groups was found. Frequency of headache types in systemic lupus erythematosus patients was: migraine 24%, tensional-type headache 11%, and mixed headache 5%. In systemic lupus erythematosus patients the risk factors associated with headaches were Raynaud's phenomenon (OR 3.6; 95% CI 1.3-9.5; P = 0.009) and β2GPI antibody positivity (OR 4.5; 95% CI 1.2-16.2; p = 0.016). We conclude that headache is more common in systemic lupus erythematosus than in rheumatoid arthritis patients and was independently associated with Raynaud's phenomenon and β2GP-I antibodies.