Risk of gestational hypertension-preeclampsia in women with preceding endometriosis: A nationwide population-based study

PLoS One. 2017 Jul 17;12(7):e0181261. doi: 10.1371/journal.pone.0181261. eCollection 2017.

Abstract

Objective: To investigate the association between preceding endometriosis and gestational hypertension-preeclampsia (GH-PE).

Methods: 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 < 15 or > 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.

Results: 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).

Conclusions: Preceding endometriosis is an independent and significant risk factor for the occurrence of GH-PE.

MeSH terms

  • Adolescent
  • Adult
  • Age Factors
  • Comorbidity
  • Databases, Factual
  • Endometriosis / complications
  • Endometriosis / epidemiology*
  • Female
  • Humans
  • Logistic Models
  • Longitudinal Studies
  • Middle Aged
  • National Health Programs
  • Odds Ratio
  • Pre-Eclampsia / epidemiology*
  • Pre-Eclampsia / etiology
  • Pregnancy
  • Risk Factors
  • Socioeconomic Factors
  • Taiwan
  • Time Factors
  • Urban Population
  • Young Adult

Grants and funding

This work is supported by a grant of the Ministry of Science and Technology, Taiwan (http://www.most.gov.tw/mp.aspx?mp=7) "Multidisciplinary health cloud research program: technology development and application of big health data" for ML Pan, and a grant of Taipei Tzu-Chi Hospital, Taiwan (https://www.tzuchi.com.tw/tzuchi_en/About_TP_Center/Default.htm) (TCRD-TPE-105-18) for KH Chen. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.