Baseline Characteristics,risk Factors And Prognosis Of Pulmonary Arterial Hypertension In Patients With Lupus Nephritis

Objective: To determine the prevalence,baseline characteristics,risk factors and prognosis of pulmonary arterial hypertension(PAH)in patients with lupus nephritis(LN).Methods: From January 2007 to March 2017,387 patients diagnosed with LN in the first affiliated Hospital of Sun Yat-sen University were analyzed retrospectively.Resting transthoracic echocardiography was used to estimate the pulmonary artery systolic pressure(PASP),and PAH was defined as PASP ? 35 mmHg.Calculating the prevalence of LN with PAH.The clinical baseline characteristics and laboratory tests were compared between the two groups,and a logistic regression model was established to screen for risk factors of LN with PAH.Patient outcomes(renal result events and all-cause mortality)were recorded during the follow-up.The endpoint of the renal outcome was defined as doubling of baseline serum creatinine(D-SCr),progression to end-stage renal disease(ESRD)or all-cause death.The survival curve was plotted using the Kaplan-Meier method,and the influence of PAH on the outcomes were analyzed by Cox regression model.Results : PAH was prevalent in 100(25.63%)of the 387 patients studied.Compared to patients without PAH,those with PAH had higher pleuritic rate(p=0.003),mean arterial pressure(MAP)(p=0.001),blood urea nitrogen(BUN)(p<0.001),SCr levels(p=0.001),c-reactive protein(CRP)(p=0.005),frequency of anti-double-stranded DNA antibodies(p=0.006),activity index(AI)score(p=0.014),and chronic kidney disease(CKD)stage(p=0.015;CKD 1: 27.00% versus 41.11%,p=0.012;CKD 4: 22.00% versus 11.15%,p=0.007).However,PAH was associated with lower acute rash frequency(p=0.049),hemoglobin levels(p<0.001),C3 levels(p=0.019),C4 levels(p=0.048),and eGFR values(p=0.001).The independent riskfactors for PAH were MAP(OR,1.024;95% CI: 1.006-1.043;p=0.011)and anti-dsDNA antibodies(OR,4.169;95% CI: 1.195-14.544;p=0.025).Hemoglobin(OR,0.984;95% CI: 0.970-0.999;p=0.031)was a protective factor for patients with LN combined with PAH.Over the median follow-up of 49 months,75 patients(19.38%)reached the renal outcomes,and 34(45.33%)of them died.The cause of death was excluded(18.67%),the most common cause of death was infection(14.67%),followed by cardiovascular events(6.67%).Kaplan-meier survival analysis showed that the incidence of renal outcome events(p=0.007)and total death rate(p=0.031)were significantly higher among patients with PAH.Multivariate Cox regression analysis revealed that the CI score(HR,1.177;95%CI:1.011-1.370;p=0.036)was a risk factor,and eGFR(HR,0.983;95% CI: 0.973-0.993;p=0.001)was a protective factor for renal outcome in patients with LN.Baseline age(HR,1.051;95% CI: 1.023-1.080;p<0.001)and MAP(HR,1.043;95% CI: 1.013-1.075;p=0.005)were important risks affecting all-cause mortality in patients with LN factor.Female sex(HR,1.043;95% CI: 1.013-1.075;p=0.005)and(HR,0.254;95% CI:0.075-0.866;p=0.029)were protective factors affecting all-cause mortality in patients with LN.However,PAH was not an independent risk factor of either composite outcome or mortality.Conclusions: This study found that patients with LN have a high prevalence of PAH and a poor prognosis.And it was further confirmed that the most common cause of death in patients with LN is infection,followed by cardiovascular events,regardless of whether they are associated with PAH.The CI score is a risk factor and eGFR is a protective factor for renal prognosis of LN.Baseline age and MAP are the risk factors,and female sex,HDL are protective factors for all-cause mortality in patients with LN-associated PAH.