National trends in inpatient endometriosis admissions: Patients, procedures and outcomes, 2006−2015

Introduction
Despite guidance towards minimally invasive, outpatient procedures for endometriosis, many patients nonetheless receive inpatient care. Our objective was to assess trends in patient and hospital characteristics, surgical complications and hospital charges for women with an endometriosis-related inpatient admission in the United States.
Methods
We conducted a pooled cross-sectional analysis of Healthcare Cost and Utilization Project Nationwide Inpatient Sample data. Visits were stratified into three time-period-defined cohorts (2006–2007, 2010–2011, and 2014 through the first three quarters of 2015). Visits were included if the patient was aged 18–49 years and the primary diagnosis code was for endometriosis (International Classification of Diseases, 9th Revision code 617.xx). We evaluated counts of inpatient admissions and rates of patient and hospital characteristics.
Results
The number of inpatient admissions with a primary diagnosis code for endometriosis decreased by 72.8% from 2006 to 2015. At the same time, among those admitted for inpatient care for endometriosis, the proportions who had Medicaid insurance and multiple documented comorbidities increased. From 2006 to 2015, mean total hospital charges increased by 75% to $39,662 in 2015 US dollars, although average length of stay increased by <1 day.
Conclusions
The number of inpatient admissions with a primary diagnosis of endometriosis decreased over the past decade, while surgical complications and associated hospital charges increased. The share of patients with multiple comorbidities increased and an increasing proportion of inpatient endometriosis admissions were covered by Medicaid and occurred at urban teaching hospitals. These findings suggest a demographic shift in patients receiving inpatient care for endometriosis towards more complex, vulnerable patients.

引言
尽管目前针对子宫内膜异位症（Endometriosis）已有微创门诊手术的诊疗指南，但仍有众多患者需接受住院治疗。本研究旨在评估美国因子宫内膜异位症相关指征住院的女性患者的人群与医院特征、手术并发症及住院费用的变化趋势。

方法
本研究针对医疗成本与利用项目（Healthcare Cost and Utilization Project, HCUP）的全国住院患者样本（Nationwide Inpatient Sample, NIS）数据开展合并横断面分析。将就诊病例按时间周期划分为3个队列（2006–2007年、2010–2011年，以及2014年至2015年前三季度）。纳入标准为患者年龄18~49岁，且主要诊断编码为子宫内膜异位症（国际疾病分类第9版[ICD-9]编码617.xx）。本研究对住院收治人次以及患者与医院特征的占比进行了评估。

结果
2006年至2015年间，以子宫内膜异位症为主要诊断的住院收治人次下降了72.8%。与此同时，在因子宫内膜异位症接受住院治疗的患者中，拥有医疗补助计划（Medicaid）保险以及存在明确记录的多种合并症的患者占比均有所上升。2006年至2015年，平均总住院费用以2015年美元计价增长了75%，达到39662美元，尽管平均住院时长仅增加了不足1天。

结论
过去十年间，以子宫内膜异位症为主要诊断的住院收治人次呈下降趋势，而手术并发症发生率及相关住院费用则有所上升。合并多种病症的患者占比不断提升，同时由医疗补助计划保险覆盖以及在城市教学医院收治的子宫内膜异位症住院患者比例持续升高。上述研究结果表明，因子宫内膜异位症接受住院治疗的患者群体在人口学特征上出现变化，逐渐转向病情更复杂、属于弱势的患者群体。