The estimated prevalence and incidence of endometriosis with the Korean National Health Insurance Service-National Sample Cohort (NHIS-NCS): A National Population-based Study

Prevalence, incidence, and treatment trends of adenomyosis in South Korean women for 15 years: A national population-based study

OBJECTIVE

Adenomyosis is associated with female infertility worldwide. With improvements in imaging methods, such as pelvic magnetic resonance imaging, the diagnosis and treatment of adenomyosis have changed. This study aimed to evaluate the overall prevalence, incidence, and treatment trends of adenomyosis in South Korea using data from the Korean National Health Insurance Service Database (NHIS).

METHODS

Data were collected from the Korean NHIS, a population-based complete enumeration database. A total of 678 641 women aged 11-55 years diagnosed with adenomyosis (N80.0 ICD-10 code) from the database from 2002 to 2016 were enrolled. After applying a one-year look-back method, 629 592 patients were analyzed to estimate the prevalence, incidence, and treatment trends of adenomyosis.

RESULTS

The overall prevalence during the study period was 3.86 per 1000 people. The prevalence of adenomyosis has increased from 1.42 per 1000 individuals in 2002 to 7.50 per 1000 individuals in 2016. The crude annual incidence rate of adenomyosis was 1.62 per 1000 people in 2003, which increased to 4.12 per 1000 people in 2016. In addition, the proportion of uterus-preserving surgeries in adenomyosis treatments has increased from 7.51% to 21.29% over 15 years.

CONCLUSION

The prevalence and incidence of adenomyosis in South Korea increased between 2002 and 2016. Furthermore, the proportion of uterus-preserving surgeries and progestin prescriptions for adenomyosis treatment has increased. We expect that our findings will raise awareness of the necessity for fertility preservation through earlier diagnosis and proper management of patients with adenomyosis.

Comprehensive evaluation of the incidence and prevalence of surgically diagnosed pelvic endometriosis in a complete population

INTRODUCTION

The incidence and prevalence of pelvic endometriosis is still being debated. Population-based studies have shown annual incidences between 0.1% and 0.3%, which translates to a prevalence of symptom-giving disease of between 2% and 6% over a 20-year span in the reproductive years. However, a prevalence of 10% or higher is often assumed. We used Iceland's extensive record linkage possibilities, secure access to patient data and personal identification numbers to search for all cases with a surgical and/or histological first diagnosis over a 15-year study period.

MATERIAL AND METHODS

Information was obtained from all healthcare facilities where an operative and/or histological diagnosis of pelvic endometriosis might have been made during 2001-2015. Hospital discharge diagnostic data and private clinic data sources were scrutinized and double-checked through a central register. Individual medical records, operation notes and pathology records were inspected. Visually and pathologically diagnosed cases were included. The data covered women aged 15-69 years, but the age range 15-49 (reproductive years) was specifically considered. Annual incidence was estimated per 10 000 person-years and prevalence possibilities calculated for varying disease durations. Disease severity was staged (revised American Society for Reproductive Medicine classification) and main lesion sites determined.

RESULTS

A total of 1634 women 15-69 years old were diagnosed; 1487 of them between 15 and 49 years old. Histological verification was obtained for 57.1%. The age-standardized annual incidence for all confirmed endometriosis diagnoses was 12.5/10 000 person-years among women in their reproductive years. The overall estimate of prevalence was 0.6%-3.6%, dependent on duration of symptoms from 5 up to 30 years. The most common sites by order of frequency were ovaries, deep pelvis, central pelvis, vesicouterine pouch and uterine appendages. Of the women, 1080 (66.1%) had minimal/mild and 553 (33.8%) moderate/severe disease.

CONCLUSIONS

We have in a comprehensive study covering a recent 15-year period confirmed an annual incidence of pelvic endometriosis of between 0.1% and 0.15% in the female population of reproductive age. Endometriosis is variably severe but, depending on the duration of symptomatic disease, the approximated prevalence during women's reproductive years could range from 1% to 4%.

Current treatments for endometriosis in South Korea: an analysis of nationwide data from 2010 to 2019

While a wide range of treatments, including medical therapies and surgery, are used to manage endometriosis, the characteristics and treatment status of patients who received these treatments have not been investigated in Korea. This study analyzed the Korean Health Insurance Review & Assessment Service-National Patient Sample (HIRA-NPS) data from 2010 to 2019 with 7530 patients diagnosed with endometriosis. Annual trends in the types of visit and surgery, medication prescriptions and associated costs were investigated. The analysis showed that surgery slightly decreased among the types of utilized healthcare services (2010: 16.3, 2019: 12.7), dienogest prescription rapidly increased due to national health insurance coverage from 2013 (2013: 12.1, 2019: 36.0), and the use of gonadotrophin-releasing hormone analogues decreased (2010: 33.6, 2019: 16.4). There was no significant change in total and outpatient costs per person over time. Regarding endometriosis treatment, conservative treatment mainly based on prescribed medications has been gradually replacing surgery. Particularly, the listing of dienogest for national health insurance coverage might have affected the trend. However, there were no significant changes in terms of total and medication costs per person.

Endometriosis prevalence and incidence trends in a large population-based study in Catalonia (Spain) from 2009 to 2018

Objective:

Endometriosis greatly impacts women’s health and quality of life. However, research on the prevalence and incidence of endometriosis remains inconclusive. This study assesses time trends in the prevalence and incidence of endometriosis diagnoses in Catalonia (Spain) from 2009 to 2018, considering differences by age and socioeconomic status.

Methods:

Population-based cohort study using data from the Information System for Research in Primary Care (SIDIAP) database. Data were included from over 2.4 million women aged 15–55 years between 1 January 2006 and 31 December 2018.

Results:

A total of 2,337,717 women were selected as the incident population; 0.7% had an endometriosis diagnosis. Median (interquartile range) age at diagnosis was 37 (32–43) years. Most women were European (92.3%) and lived in urban areas (73.6%). Overall prevalence of endometriosis consistently increased during the 2009–2018 period, and it was 1.24% in 2018. Trends were the highest for women with less socioeconomic deprivation and for the 35–44 years age group. Median incidence rates were 94.9 (92.6–102.9) per 100,000 women-years, being the highest in women aged 35–44 years throughout the whole study period. Overall, incidence increased between 2015 and 2017, and plateaued or decreased in 2018. Incidence rates in women from the most deprived and rural areas were lower, although incidence time trends by socioeconomic status were unclear.

Conclusion:

Healthcare services and public health strategies need to be strengthened to ensure timely endometriosis diagnosis and treatment. Special attention should be given to the most affected populations and the social inequities of health.

Increasing incidence and spatial hotspots of hospitalized endometriosis in France from 2011 to 2017

Endometriosis is a female hormone-dependent disease, possibly related to endocrine disruptor exposure. We aimed to monitor this disease nationwide in France and analyze spatial trends at a fine scale to explore possible environmental contributing risk factors. We conducted a retrospective national descriptive study from 2011 to 2017 in females aged 10 years old and over, using comprehensive hospital discharge data. Cases were identified using ICD-10 N80 codes and were localized at their municipality of residence. We defined incident cases as the first hospital stay of patients, without a stay in at least the previous 5 years. We performed statistical analyses according to age and type of endometriosis, and we modeled the temporal, spatial and spatiotemporal trends. We identified 207,462 incident cases of all-type hospitalized endometriosis (83,112 for non-adenomyosis cases). The crude incidence rate for the study period was 9.85/10,000 person-years (3.95/10,000 for non-adenomyosis cases). From 2011 to 2017, the risk of all-type endometriosis increased by 8.5% (95% CI: 3.9; 13.4) (by 3.6% (95% CI: 0.6; 6.8) for non-adenomyosis cases). The risk was geographically heterogeneous, with 20 high-risk hotspots, showing similar results for non-adenomyosis cases. Shifting practice patterns, improved awareness and healthcare disparities interlinked with environmental risk factors could explain these trends.

Trends in the Incidence and Survival Rates of Primary Ovarian Clear Cell Carcinoma Compared to Ovarian Serous Carcinoma in Korea

Objective

To compare the incidence and survival rates of primary ovarian clear cell carcinoma (OCCC) and ovarian serous carcinoma (OSC) from a nationwide collected database.

Methods

We extracted information of patients with primary OCCC and OSC from the Korea Central Cancer Registry recorded between 1999 and 2018, including age at diagnosis and the Surveillance, Epidemiology, and End Results summary stage. Age-standardized incidence rates (ASRs) and annual percent changes (APCs) were calculated. Baseline characteristics and overall survival (OS) were compared between the OCCC and OSC groups.

Results

Overall, the incidence rate of primary OCCC increased markedly from 1999 (ASR, 0.16/100,000) to 2018 (0.76/100,000) (APC, 7.85%; P<0.0001). Patients with OCCC were significantly younger and had early-stage disease more frequently than those with OSC. Patients diagnosed with OCCC before the age of 50 showed better OS than those diagnosed after the age of 50 (P=0.0048). The 5-year OS of the OCCC group did not differ by study period [73.5% (1999–2008) vs. 75.4% (2009–2018), P=0.3187], whereas the 5-year OS of the OSC group improved from 54.4% to 58% (P=0.0003).

Conclusions

Our nationwide registry-based study demonstrated that the incidence of OCCC in Korea increased significantly from 1999 to 2018. Early-stage OCCC had a relatively good prognosis, but advanced-stage OCCC had a worse OS than advanced-stage OSC. Therefore, the development of optimal treatment strategies for OCCC is warranted.

Peroxisome Proliferator-Activated Receptor Alpha (PPAR-α) as a Regulator of the Angiogenic Profile of Endometriotic Lesions

Endometriosis is a disease that affects a significant proportion of women and its infiltrative pattern is entirely dependent on the vascular supply of lesions. Several factors seem to trigger the process of angiogenesis in endometriotic lesions. During the last years, peroxisome proliferator-activated receptors (PPARs), a group of nuclear proteins that regulate gene transcription and that seem to regulate energy consumption and expenditure, have been also implicated in the pathophysiology of angiogenesis. Their ability to regulate the course of cancer and improve the survival rates of patients has been extensively studied and seems to be partially dependent on alteration of the vascular supply of malignant lesions. Research in the field of endometriosis is scarce in the international literature and mainly focused on PPAR-gamma. However, indirect evidence suggests that PPAR-alpha (PPAR-α) may also regulate the vascular supply of endometriotic lesions as well. Specifically, PPAR-α agonists seem to downregulate angiogenesis by increasing the expression of several anti-angiogenic molecules, including thrombospondin-1 (TSP-1) and gypenoside 140 (gp140), as well as factors that are involved in the mitogen-activated protein kinase cascade. In the present article, we summarize existing indirect and direct evidence that indicates the existence of an association between the expression of PPAR-α and endometriosis to help future research in this field.

Spatial Patterns of Endometriosis Incidence. A Study in Friuli Venezia Giulia (Italy) in the Period 2004-2017

Background: Diagnosis of endometriosis and evaluation of incidence data are complex tasks because the disease is identified laparoscopically and confirmed histologically. Incidence estimates reported in literature are widely inconsistent, presumably reflecting geographical variability of risk and the difficulty of obtaining reliable data. Methods: We retrieved incident cases of endometriosis in women aged 15–50 years using hospital discharge records and pathology databases of the Friuli Venezia Giulia region in the calendar period 2004–2017. We studied the spatial pattern of endometriosis incidence applying Bayesian approaches to Disease Mapping, and profiled municipalities at higher risk controlling for multiple comparisons using both q-values and a fully Bayesian approach. Results: 4125 new cases of endometriosis were identified in the age range 15 to 50 years in the period 2004–2017. The incidence rate (x100 000) is 111 (95% CI 110–112), with a maximum of 160 in the age group 31–35 years. The geographical distribution of endometriosis incidence showed a very strong north-south spatial gradient. We consistently identified a group of five neighboring municipalities at higher risk (RR 1.31 95% CI 1.13; 1.52), even accounting for ascertainment bias. Conclusions: The cluster of 5 municipalities in the industrialized and polluted south-east part of the region is suggestive. However, due to the ecologic nature of the present study, information on the patients’ characteristics and exposure histories are limited. Individual studies, including biomonitoring, and life-course studies are necessary to better evaluate our findings.