The effects of different hormone replacement therapy regimens on tear function, intraocular pressure and lens opacity

Objective. Estrogen may have adverse effects on the ocular surface, intraocular pressure (IOP), lens opacity and tear function. The aim of the present study was to elucidate the effects of different hormone replacement therapy (HRT) protocols on tear function, IOP and lens opacity. Design and setting. This was a prospective, uncontrolled study carried out at the Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, Faculty of Medicine, Uluda University, Turkey. Patients and interventions. Thirty postmenopausal patients who had spontaneous or surgical menopause for at least 1 year and were not taking any medications were assigned to one of three groups. Group 1 comprised 19 patients (n = 38 observations) given conjugated equine estrogen 0.625 mg plus medroxyprogesterone acetate 2.5 mg (Premelle 2.5®) daily; Group 2 contained six patients (n = 12 observations) given tibolone 2.5 mg (Livial®) daily; and Group 3 comprised five patients (n = 10 observations) treated with estradiol patch, 3.9 mg 12 cm2 (Climara®). Tear function, evaluated with Schirmer's test, IOP and lens opacity were determined before treatment and at 6 and 12 months of treatment. Results. Mean Schirmer's test score in each group and all eyes (n = 60) did not change significantly after 6 months of treatment but decreased significantly at 12 months. The percentage decrease in tear function was greatest in the estrogen-only group (Group 3). Mean IOP did not change significantly in Groups 1 and 2; however, in Group 3, IOP showed a statistically significant decrease from 14.63 ± 0.84 mmHg before treatment to 12.60 ± 0.68 mmHg (mean ± standard error) at the end of treatment. Lens opacity in women of all groups did not change during treatment. Conclusions. HRT decreased tear production, the decrease being greater in the estrogen- only group. Woman who are taking or considering HRT should be informed of the potential increased risk of dry eye syndrome with this therapy. In addition, estrogen-only treatment decreased IOP while estrogen plus progesterone and tibolone had no effect. HRT did not affect lens opacity after 12 months of treatment.