PLoS ONE (Jan 2017)
Risk of gestational hypertension-preeclampsia in women with preceding endometriosis: A nationwide population-based study.
Abstract
To investigate the association between preceding endometriosis and gestational hypertension-preeclampsia (GH-PE).In this nationwide population-based longitudinal study, data from 1998-2012 Taiwan National Health Insurance Research Database were used. We used ICD9-CM codes 617.X and 642.X respectively for the diagnoses of endometriosis and GH-PE, which were further confirmed by examining medical records of surgeries, blood pressure and urine protein to ensure the accuracy of the diagnoses. The study excluded women diagnosed with endometriosis at 45 years of age, chronic hypertension, and GH-PE prior to endometriosis. Each pregnant woman with a prior diagnosis of endometriosis was matched to 4 pregnant women without endometriosis by age. Logistic regression analysis was used to calculate odds ratios (ORs) for the risk of GH-PE with adjustment for age, occupation, urbanization, economic status and comorbidities.Among 6,300 women with a prior endometriosis diagnosis who were retrieved from a population of 1,000,000 residents, 2,578 (40.92%) had subsequent pregnancies that were eligible for further analysis and were compared with 10,312 pregnant women without previous endometriosis. GH-PE occurred more in women with prior endometriosis as compared to those without endometriosis (3.88% vs. 1.63%, p<0.0001). Further analysis revealed prior endometriosis was associated with GH-PE (adjusted OR = 2.27; 95% CI:1.76-2.93). For danazol-treated and non-danazol-treated subgroups, the incidences of GH-PE were 3.13% (15/480) and 4.05% (85/2,098), respectively. Although the risk for subsequent GH-PE was lower (adjusted OR = 1.49; 95% CI:0.86-2.56) after receiving danazol treatment than average (adjusted OR = 2.27; 95% CI:1.76-2.93) for women with preceding endometriosis, the reduction of risk was not statistically remarkable for danazol-treated (adjusted OR = 1.49) vs. non-danazol-treated (adjusted OR = 2.48) subgroups (p heterogeneity = 0.12).Preceding endometriosis is an independent and significant risk factor for the occurrence of GH-PE.