The risk factors that predict chronic hypertension after delivery in women with a history of hypertensive disorders of pregnancy

Hypertensive disorders of pregnancy (HDP) is one of the most important lethal complications in pregnant mothers. It is also associated with the subsequent development of chronic hypertension. The objective of this study was to identify the clinical risk factors of postpartum chronic hypertension in women diagnosed with HDP. Six hundred patients as HDP, who diagnosed and followed-up at least 6month after delivery,were included in the study.We divided the included subjects in 2 groups based on the development of postpartum chronic hypertension: presenting with the chronic hypertension, ''case group'' (n=41) and without chronic hypertension, ''control group'' (n=559). Clinical and demographic factors were evaluated. By multiple regression analysis, early onset hypertension with end-organ dysfunction, smoking, higher prepregnancy body mass index (BMI), and comorbidities, systemic lupus erythematosus (SLE) or antiphospholipid syndrome (APLS), were associated with progression to chronic hypertension in the postpartum period. The value of area under the curves (AUC) for the 5 models, that generated to combine the significant factors, increased from 0.645 to 0.831, which indicated improved prediction of progression to the chronic hypertension. Additional multivariate analysis revealed significant specific risk factors. This retrospective single hospital-based study demonstrated that the clinical risk factors, that is early onset hypertension with end-organ dysfunction, smoking, and higher prepregnancy BMI, were significant independent predictors of chronic hypertension in women after delivery. Identification of risk factors allowed us to narrow the subject field formonitoring and managing high blood pressure in the postpartum period.