title: Presentation of SLE in UK primary care using the Clinical Practice Research Datalink.
abstract: OBJECTIVE
  To describe the presenting symptoms of SLE in primary care using the Clinical Practice Research Database (CPRD) and to calculate the time from symptom presentation to SLE diagnosis.
  
  
  METHODS
  Incident cases of SLE were identified from the CPRD between 2000 and 2012. Presenting symptoms were identified from the medical records of cases in the 5 years before diagnosis and grouped using the British Isles Lupus Activity Group (BILAG) symptom domains. The time from the accumulation of one, two and three BILAG domains to SLE diagnosis was investigated, stratified by age at diagnosis (<30, 30-49 and ≥50 years).
  
  
  RESULTS
  We identified 1426 incident cases (170 males and 1256 females) of SLE. The most frequently recorded symptoms and signs prior to diagnosis were musculoskeletal, mucocutaneous and neurological. The median time from first musculoskeletal symptom to SLE diagnosis was 26.4 months (IQR 9.3-43.6). There was a significant difference in the time to diagnosis (log rank p<0.01) when stratified by age and disease severity at baseline, with younger patients <30 years and those with severe disease having the shortest times and patients aged ≥50 years and those with mild disease having the longest (6.4 years (IQR 5.8-6.8)).
  
  
  CONCLUSIONS
  The time from symptom onset to SLE diagnosis is long, especially in older patients. SLE should be considered in patients presenting with flaring or chronic musculoskeletal, mucocutaneous and neurological symptoms.
authors.affiliation: Department of Pharmacy & Pharmacology , University of Bath , Bath , UK.
authors.forename: Alison L
authors.initials: AL
authors.lastname: Nightingale
authors.affiliation: Worldwide Epidemiology, GlaxoSmithKline R&D, Stockley Park , London , UK.
authors.forename: Julie E
authors.initials: JE
authors.lastname: Davidson
authors.affiliation: U.S. Health Outcomes, GlaxoSmithKline, Research Triangle Park , North Carolina , USA.
authors.forename: Charles T
authors.initials: CT
authors.lastname: Molta
authors.affiliation: U.S. Medical Affairs, GlaxoSmithKline , Philadelphia, Pennsylvania , USA.
authors.forename: Hong J
authors.initials: HJ
authors.lastname: Kan
authors.affiliation: Department of Pharmacy & Pharmacology, University of Bath, Bath, UK; Royal National Hospital for Rheumatic Diseases, Bath, UK.
authors.forename: Neil J
authors.initials: NJ
authors.lastname: McHugh
keywords: Clinical Practice Research Datalink; Diagnostic Delay; Epidemiology; Primary Care; Systemic Lupus Erythematosus