Background:Systemic lupus erythematosus(SLE)is a chronic autoimmune multiorgan disease of unknown etiology.Antiphospholipid Syndrome(APS)is an autoimmune disorder characterised by the presence of antiphospholipid antibodies and a state of hypercoagulability with increased tendency to thrombotic events and obstetric morbidity.The polyautoimmuntity of APS and SLE is a reflection of complex disease traits.However,there have not been many studies addressing this issue,especially its implications in relation to optimal treatment.Objective:We aim to compare the clinical manifestations in SLE patients with and without APS for an early disease diagnosis.Methods:Medline and Embase databases have been searched for studies comparing SLE patients with and without APS and clinical manifestations were considered as the endpoints.A fixed effect model has been used where a small heterogeneity was observed.Odd Ratio(OR)with 95%confidence interval(CI)was used to express the pooled effect on dichotomous variables and the pooled analyses were performed with RevMan 5·3.Results:This meta-analysis included eleven studies consisting of a total of 1990 SLE patients(330 patients with APS and 1660 without APS).Cardiovascular manifestations,obstetric morbidities and venous thrombosis were significantly higher in SLE patients with APS with OR:2.56,95%CI:1.37 – 4.76; P = 0.003; OR:14.30,95%CI:7.98 – 25.63; P < 0.00001 and OR:13.62,95%CI:6.96 – 26.63; P < 0.00001 respectively.Conclusion:Coexistence of APS with SLE gives rise to a higher rate of thromboembolic events and obstetric morbities and adversely impacts the cardiovascular manifestations.