Results indicated that the total number of inpatients was less in January and February, and there was no significant difference in the number of inpatients between other months. The ratios of patients with active SLE relative to total inpatients are shown in Table 2 . The trend of relative ratios of patients with active SLE was consistent with that of the absolute number of patients with active SLE. Namely, that the relative ratios of patients with active SLE were the highest in December, January and February, and lowest in July, August and September. The relative ratio of patients with active SLE was significantly higher in winter (December, January and February) than in spring (March, April and May), summer (June, July and August) and autumn (September, October and November) (p,0.001). There was no statistical significance in relative ratios of patients with active SLE between spring, summer and autumn (p.0.05).