Epidemiology of hypertensive disorders in pregnancy: prevalence, risk factors, predictors and prognosis.

Hypertensive disorders in pregnancy (HDP) represent some of the most important problems faced by public health because HDP is a major cause of maternal and prenatal morbidity and mortality. Several epidemiological studies have been performed to determine the prevalence and risk factors of HDP as well as its subtypes. The prevalences of HDP, gestational hypertension and preeclampsia are 5.2-8.2%, 1.8-4.4% and 0.2-9.2%, respectively. Body mass index, anemia and lower education appear to be modifiable risk factors for HDP. Maternal age, primiparous, multiple pregnancy, HDP in previous pregnancy, gestational diabetes mellitus, preexisting hypertension, preexisting type 2 diabetes mellitus, preexisting urinary tract infection and a family history of hypertension, type 2 diabetes mellitus and preeclampsia appear to be nonmodifiable risk factors. Genetic variants including a single-nucleotide polymorphism in the angiotensinogen gene have also been reported to be nonmodifiable risk factors. Epidemiological studies have recently examined the associations between a history of HDP and its subtypes and future risks of other diseases. These studies have reported associations between a history of HDP and a risk of coronary heart disease, heart failure, dysrhythmia, stroke, hypertension, diabetes mellitus, end-stage renal dysfunction and cardiomyopathy. HDP is not associated with the future incidence of total cancer. In conclusion, HDP is not a rare complication of pregnancy and the influence of HDP remains for an extended duration. Physicians should consider the effects of HDP when treating chronic diseases in women.