This observational, single-center study was conducted on a sample of women with endometriosis referred to a center for diagnosis and treatment of endometriosis with dedicated physicians, psychologists, and nurses, of the Department of Obstetrics and Gynecology at the ARNAS Civico Hospital in Palermo, in Southern Italy, between October 2019 and June 2021.
Participants
85 women with endometriosis were consecutively recruited. All patients received personalized clinical indications regarding the use of medical therapy with DNG and EE/DNG administered orally. Side effects were collected during routine clinical practice, two participants reported vaginal bleeding and loss of libido were excluded from the final data analysis because they spontaneously suspended their therapy. Nineteen participants were excluded because of missing data.
Finally, 64 women completed all study procedures, 36 (56%) took DNG and 28 (44%) took EE/DNG. These women reported that treatment was well tolerated and that the therapy wellness was superior to the side effects.
According to routine practice, women came back for clinical assessment and psychological evaluation after 18 months (T1), and completed all measures at both Time 0 (T0) and Time 1 (T1), (Fig. 1). Some women (50%) performed the T1 procedures a few weeks after the visit scheduled at 18 months because of patients’ specific clinical needs; this variability was taken into account in the analysis as a covariate.
All subjects gave written informed consent. The individual privacy of clinical data was guaranteed under Italian law. Eligible for the study were women aged 18 years or more not seeking pregnancy, with a surgical diagnosis or a clinical/instrumental diagnosis of endometriosis, who had been taking DNG or EE/DNG at the time of recruitment.
Procedures
Quality of life: questionnaire (QoL) Short Form Survey “SF-36”
The questionnaire consisted of 36 items, and transformed to give eight summary scales measuring health concepts, summarized in two component factors: physical health (PCS) and mental health (MCS). The raw scores were converted into standard scores (M=50 ±10), range 0-100, in accordance with the questionnaire guidelines [20].
Health-Related Quality of Life (HRQoL) Endometriosis Health Profile 30 “EHP-30”
This is a disease-specific tool to evaluate the HRQoL in women suffering from endometriosis. The EHP-30 is composed of two parts: a core questionnaire containing five scales applicable to all women with endometriosis (30 items): pain, control and powerlessness, emotional wellbeing, social support, self-image and a modular part containing six scales which do not necessarily apply to all women with endometriosis (23 items): work life, relationship with children, sexual intercourse, medical profession, treatment and infertility. The score ranging from 0 (best possible health status) to 100 (worst possible health status) [21].
Index of sexual satisfaction “ISS”
This scale aims to assess problems relating to the sexual aspects of a relationship, measuring subject’s feelings about behaviors, attitudes, events, affective states and preferences associated with sexual intercourse between partners. It contains 25 questions, the obtained scores ranged from 0 to 150. A cutoff score ≥75, indicates a higher degree of sexual satisfaction [22].
Visual Analogical Scale “VAS”
The Visual Analogic Scale was used to define endometriosis-associated pain, chronic pelvic pain, dysmenorrhea, dyspareunia and dyschezia.
The instrument measures the pain level across a continuum of values, from the patient's perspective their pain does not make discrete jumps, as a categorization of none, mild, moderate and severe would suggest. VAS is a horizontal line, 100 mm in length, anchored by word descriptors at each end. The patient marks on the line the point that they feel represents their perception of their current state. VAS has been repeatedly used in the literature as a way to measure patients’ perceived pain [23-24].
Study variables
- Dysmenorrhea, dyspareunia and dyschezia;
- Presence of spotting, headache, weight gain, low libido
- Age
- Age at menarche
- Age diagnosis
- Age first symptoms
- Duration Untreated Endometriosis (DUE) refers to the period (years) between the onset of endometriosis symptoms and the diagnosis
- Presence of children in the household and their age
- Volume of endometrioma sagittal and antero-posterior compartment
Statistical analysis
All statistical analyses were performed using the SPSS statistical software version 20, with screening for missing data.
A tool was performed [25] in order to determine the minimum total sample size required for this study, and the results showed that at least 54 participants were needed to register an alpha level of 0.05 and to have 80% power.
Descriptive statistics were used to summarize the study participants’ clinical and psychological variables presented as mean (SD), median values (range) and frequency (%) as appropriate according to data distribution. The differences in patient characteristics between treatment groups (DNG and EE/DNG) were assessed with the Sample T Test and χ2. The psychological and clinical differences between treatment groups (DNG and EE/DNG) were performed using the Sample T Test and Mann Whitney’s U. The correlation between chronological, clinical and psychological variables both at T0 and at T1 were performed with R Pearson. The effect of treatment over time on the clinical and psychological variables were evaluated by a 2 (treatment) × 2 (time) mixed-design analysis of variance (ANOVA). The independent variable was given by the 2 approaches to treatment: DNG and EE/DNG. The dependent variables were EHP-30, SF-36, ISS, VAS, dysmenorrhea, dyspareunia and dyschezia with checks for clinical variables that differed by group (age diagnosis, DUE and time variability). The level of significance was set at alpha = 0.05.