We reviewed the charts of consecutive patients with a diagnosis of acute CSC referred to the Medical Retina and Imaging Division of San Raffaele Hospital (Milan, Italy) and to the Fondazione G. B. Bietti-IRCCS (Rome, Italy) between January 2016 and July 2017, treated with eplerenone or with observation. All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Informed consent was obtained from all individual participants included in the study.
Patients were eligible for inclusion if they were at least 18 years of age, with a diagnosis of acute CSC, defined by the presence of subretinal fluid and visual symptoms for less than 12 weeks, and were experiencing an episode of CSC for the first time. Exclusion criteria were the presence of chronic CSC (duration of visual symptoms more than 12 weeks) or recurrent CSC (patients with a history of one or more previous CSC attacks), presence of choroidal neovascularization (CNV) identified by FA, ICGA and/or OCT angiography (OCT-A), any treatment for retinal disease (including intravitreal injections, photodynamic therapy, laser photocoagulation, vitrectomy), history of other retinal disorders (including age-related macular degeneration, choroidal neovascularization, diabetic retinopathy, uveitis or pathologic myopia) and the presence of any other systemic condition for which eplerenone was contraindicated (such as severe renal, cardiac or hepatic failure, pregnancy, baseline serum potassium greater than 5.0 mEq/L, concomitant administration of potassium-sparing diuretics, potassium supplements, strong CYP3A4 inhibitors, angiotensin-converting enzyme inhibitors or angiotensin receptor blockers).
All patients who met the inclusion criteria were assigned to either the treatment group (treated with eplerenone) or the observation group. All patients treated with eplerenone were consecutively included at San Raffaele Hospital, while all observed subjects were consecutively included at the Fondazione G. B. Bietti-IRCCS. The follow-up period was 3 months.
The patients in the treatment group were treated with eplerenone 25 mg/day for 1 week and then 50 mg/day for 11 weeks. Serum potassium and creatinine assessment were performed at baseline before starting treatment and monthly during treatment. Eplerenone was discontinued in the case of increased serum potassium or creatinine or in cases of drug intolerance.
At baseline, each patient underwent assessment of BCVA on standard ETDRS charts, converted into logarithm of the minimal angle of resolution (logMAR) for statistical analysis, along with comprehensive ophthalmological examination and multimodal imaging by fundus autofluorescence, FA, ICGA and spectral domain-OCT (SD-OCT; Spectralis HRA+OCT [Heidelberg Retina Angiograph + OCT]; Heidelberg Engineering, Heidelberg, Germany) and swept-source OCT-A (PLEX Elite 9000; Carl Zeiss Meditec Inc., Dublin, CA, USA). Patients included in the study were followed up at 1 and 3 months with BCVA, IOP, biomicroscopy, SD-OCT and OCT-A examinations.
SD-OCT evaluation included CMT analysis using macular thickness maps. Manual measurement of subfoveal retinal fluid (SRF) height was performed for each control, measuring the distance between the end of the outer segment and the retinal pigment epithelium at the foveal center. The subfoveal choroidal thickness (CT), defined as the vertical distance between the hyper-reflective line of Bruch’s membrane and the chorio-scleral interface, was measured manually using an enhanced-depth imaging (EDI) technique.
The main outcome measures included comparisons of BCVA, CMT, SRF and subfoveal CT between the treatment and control groups and at all time points. Safety analysis and treatment tolerance were recorded at each visit.
Statistical analyses were performed using SPSS Statistics version 20 software (IBM Corp., Armonk, NY, USA). Results of descriptive analyses were expressed as means ± standard deviations for quantitative variables, and as counts and percentages for categorical variables. Associations between categorical variables were analyzed using Fisher’s exact test. The Gaussian distribution of continuous variables was verified with the Kolmogorov–Smirnov test. Comparisons of age, CSC duration, BCVA, CMT, SRF and subfoveal CT between treatment and control groups were performed using the Student independent samples t test. Comparisons of BCVA, SRF, CMT and subfoveal CT between the three time points were performed using repeated measures analysis of variance (ANOVA) with Bonferroni correction for post hoc analysis. In all analyses, p values < 0.05 were considered statistically significant.