Real-World Evaluation of Direct and Indirect Economic Burden Among Endometriosis Patients in the United States

This retrospective study estimated the incremental direct and indirect costs associated with endometriosis among commercially insured patients in the USA and showed that the direct healthcare costs for endometriosis patients measured both 12 months prior to and after endometriosis diagnosis were significantly higher than those in matched controls. Additionally, costs due to work loss through absenteeism, STD, and LTD were also higher in patients with endometriosis. To our knowledge, this is the first major study that compared both direct and indirect healthcare costs between patients with and without endometriosis.

Analogous to the findings of previous studies [9, 13, 14] this study showed that endometriosis patients incurred significantly higher healthcare costs compared to controls. The incremental costs per patient in the first year post-diagnosis (over $10,000 with multivariable adjustment) are substantial compared to estimates for other common gynecological ailments such as uterine fibroids ($6873 in 2014 US$ [18]) or menorrhagia ($2878 in 2014 US$ [19]). Notably, over 60% of the total annual healthcare costs for endometriosis patients were accrued within 3 months of the index date, thereby adding to the existing body of literature which has reported highest healthcare resource utilization and costs in the first year after endometriosis diagnosis [20‐22].

Indirect costs associated with endometriosis are substantial as well, with average incremental indirect costs estimated at US $2132 per patient (adjusted estimate) in the 12 months following the index diagnosis. A point to notice here is that claims data can only capture indirect losses due to the absenteeism component; data on presenteeism (reduced productivity due to illness while on the job) was not available. Estimates from a study of European Union countries suggest that indirect costs due to presenteeism can substantially exceed the costs of absenteeism, by a factor of 2: €6298 due to presenteeism vs. €3280 due to absenteeism [14]. A study of 10 countries across multiple continents estimated that endometriosis resulted in the equivalent work loss of 6.4 h/week due to presenteeism and 4.4 h/week due to absenteeism [23] and provided indirect cost estimates for the USA of about $3200/year for absenteeism due to endometriosis symptoms and about $14,800 for presenteeism (values converted into 2014 US$). Instead of using records of absence and disability claims, that study based indirect cost estimates on responses by patients to versions of the Work Productivity and Activity Impairment (WPAI:GH) and Short-Form–36 version 2 (SF36v2), and estimated the work loss in terms of lost wages without adjustments for reduced pay for short- and long-term disability.

A previous study characterized the healthcare costs and utilization of endometriosis patients [22]. Although the prior study followed costs and utilization patterns over a longer period of time (up to 5 years for a small percentage of patients), the current analysis expands upon this previous work in several ways: by reporting endometriosis-related costs separately, examining trends within the first year post-diagnosis, and by providing multivariate models to provide cost estimates adjusted for variations in baseline covariates. It also contains a somewhat broader sample of patients, including women up to 49 years of age (as opposed to 45 years in Fuldeore et al.’s analysis [22]). Importantly, this study provides an update in an evolving field of treatment, and confirms changes in approaches to gynecological treatment.

A recent analysis shows that hysterectomies and oophorectomies (as treatments across all indications and not just endometriosis) have shown modest decreases in prevalence since the year 2000 with a dramatic shift towards outpatient instead of inpatient procedures [21]. In an analysis spanning the years 2000–2010, Fuldeore et al. [22] reported that 40% of endometriosis patients received an inpatient admission in their first year. In contrast, in the current analysis spanning the years 2010–2014 only 29% received an inpatient admission. These numbers include admissions for all reasons, not just endometriosis, but because surgical treatment is very common within the first year of diagnosis [9, 21], this is very likely related to a drop in inpatient treatment for endometriosis.

Despite changes in the treatment landscape, surgery remains a mainstay of endometriosis therapy in our analysis, with 38% of the patients undergoing a hysterectomy in the first year post diagnosis, and two-thirds undergoing a surgical procedure used to treat endometriosis. This high rate of hysterectomy in the presence of less invasive surgical interventions and pharmacotherapy might represent a diagnostic delay necessitating a more invasive treatment approach; future research should explore this further.

Most newly diagnosed endometriosis patients have incurred pharmacy claims for pain management, and an exceedingly high proportion of our sample of endometriosis patients, nearly 90%, had at least one prescription for opioids. The use of opioids for pain management for endometriosis warrants further investigation.

A notable strength of our study is that it included a large cohort of endometriosis and matched non-endometriosis patients to evaluate the direct and indirect healthcare costs. Additionally, this study provides a current cost trend for endometriosis by using data from a more contemporary time frame than previously available.

This study has several limitations inherent to administrative claims data. As patients were identified and variables were captured through administrative claims data, endometriosis-related symptoms, which are not recorded as a diagnosis on a medical claim, may not have been captured. The diagnosis of endometriosis and clinical characteristics were determined using ICD-9-CM diagnosis or procedure codes, which are subject to data coding limitations and data entry error, and it is possible that women with endometriosis may have inadvertently been included in the control group including those with symptoms but for whom a diagnosis had not been made yet or those for whom a diagnosis had not been recorded. The use of over-the-counter medications and other self-management techniques is not usually captured in the claims data, so the use of over-the-counter NSAIDs or other pain management medications is not included in our analysis. The indirect costs included in this study are limited to absenteeism and disability claims by the employee and do not include reduced presenteeism or potential caregiver burden, as well as any other humanistic burden associated with this chronic condition. The absence costs themselves may be conservative, as the disruption of missing workers may result in effectively more work loss than is reflected in each patient’s missing hours [24]. Endometriosis may have important effects, such as on the psychological well-being of patients [25‐27], that fall outside of the scope of the data used in this analysis. Finally, findings from this observational study may be prone to bias from non-random selection into the treatment group and was limited to endometriosis patients covered by Commercial health plans. Therefore, the results are not generalizable to those covered under other types of insurance or who lack coverage.