Complex relationships between inflammatory manifestations/type 1 and type 2 symptoms in systemic lupus erythematosus: A narrative literature review

Abstract

Objective: Recent studies have highlighted that systemic lupus erythematosus (SLE) is characterized by different types of symptoms: type 1 symptoms related to inflammation and disease activity and type 2 symptoms such as fatigue, anxiety-depression, and pain. Our aim was to investigate the relation between type 1 and type 2 symptoms, and their impact on health-related quality of life (HRQoL) in SLE. Methods: A literature review was conducted about disease activity/type1 and type 2 symptoms. Articles in English published after 2000 were located on Medline via Pubmed. The articles chosen evaluated at least one type 2 symptom or HRQoL using a validated scale in adult patients. Results: Overall, 182 articles were analyzed and 115 were retained including 21 randomized, controlled trials and corresponding to 36 831 patients. We found that in SLE, inflammatory activity/type 1 symptoms were mostly uncorrelated with type 2 symptoms and/or HRQoL. Several studies even showing an inverse relationship. No or weak correlation was observed in 85, 3% (92, 6%), 76, 7% (74, 4%) and 37, 5% (73, 1%) of studies (patients) for fatigue, anxiety-depression, and pain, respectively. For HRQoL, no or weak correlation was observed in 77, 5% of studies (88% of patients). Conclusion: Type 2 symptoms are poorly correlated with inflammatory activity/type 1 symptoms in SLE. Possible explanations and implications for clinical care and therapeutic evaluation are discussed.