title: [Influence of seasons on risk of flare-up of systemic lupus: retrospective study of 66 patients].
abstract: OBJECTIVE
  To establish the possible connection between visceral, arthro-cutaneous and biological spreading of systemic lupus (SL) and hours of sunlight.
  
  
  METHODS
  Retrospective study of 66 SL patients, consisting of 52 visceral and 14 arthro-cutaneous cases taking into account the chronological pattern of each new aggravation, based on 480 clinical records.
  
  
  RESULTS
  Increased frequency in visceral aggravation was observed in the post-summer period (August-January) (n = 57), as compared with the pre-summer period (February-July) (n = 25) (RR = 1.75, P = 0.006). This post-summer visceral aggravation was correlated with cutaneous affection (RR = 4.18) and absence of previous corticotherapy (RR = 3.97). Visceral and arthro-cutaneous aggravations taken together revealed a more disturbed immune balance pattern in the post-summer period (anti-dsDNA: 30 versus 25.1 IU/L [P = 0.07]; C3: 0.83 vs 0.921 IU/L [P = 0.05]; C4: 0.146 vs 0.183 [P = 0.05]), providing evidence of greater severity. Moderate thrombopenia (50-120 10(9)/L) accompanying visceral SL with antiphospholipids (n = 33) was more frequent during the post-summer period, even in the absence of aggravation (P = 0.03). The quarterly distribution of visceral aggravations was correlated with average hours of sunlight in the preceding quarter (P = 0.01).
  
  
  CONCLUSIONS
  There is a post-summer increase in the frequency and severity of visceral SL spreading correlated to cutaneous exacerbation and sunlight.
authors.affiliation: Service de médecine interne, hôpital Robert-Debré, Reims, France.
authors.forename: J
authors.initials: J
authors.lastname: Léone
authors.forename: J L
authors.initials: JL
authors.lastname: Pennaforte
authors.forename: V
authors.initials: V
authors.lastname: Delhinger
authors.forename: J
authors.initials: J
authors.lastname: Detour
authors.forename: K
authors.initials: K
authors.lastname: Lefondre
authors.forename: J P
authors.initials: JP
authors.lastname: Eschard
authors.forename: J C
authors.initials: JC
authors.lastname: Etienne
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000276:immunology / Q000503:physiopathology* / Q000517:prevention & control; D008297:Male; D010787:Photosensitivity Disorders / Q000517:prevention & control; D012189:Retrospective Studies; D012307:Risk Factors; D012621:Seasons; D013472:Sunlight
vernacular_title: Influence de la saison sur le risque de poussée systémique du lupus: étude rétrospective de 66 patients.