Ocular surface changes over the menstrual cycle in women with and without dry eye.
Gynecol Endocrinol. 2007 Jul;23(7):385-90. Versura P, Fresina M, Campos EC. Department of Surgical Science and Transplants, Section of Ophthalmology, Alma Mater Studiorum Università di Bologna, Bologna, Italy.
Aim. To analyze whether dry eye symptoms and ocular surface parameters change during different phases of the menstrual cycle. Method. Twenty-nine women of fertile age and with regular, 26-29-day menstrual cycles were included in the study. Fourteen subjects suffered and 15 did not suffer from dry eye symptoms. Symptoms were scored by the validated Ocular Surface Disease Index questionnaire. Tear production was evaluated with the Schirmer I test and the Schirmer II test (Jones test); tear stability with tear breakup time and Ferning test; and degree of dryness by the tear function index and imprint conjunctival cytology. Degree of inflammation was evaluated with conjunctival brush cytology and concentration of exudated serum albumin in tears. Hormonal cytology procedures were applied to exfoliated cells in tears. Patients were analyzed during menstruation, in the follicular phase and the luteal phase over two consecutive cycles, and results were statistically evaluated. Results. Subjective symptoms, tear production and stability, surface dryness and inflammation were significantly related to hormonal fluctuations in the menstrual cycle. In particular, the impairment of these functions appeared to be related to the estrogen peak occurring during the follicular phase, especially in patients with dry eye. Conclusion. The ocular surface is confirmed to be an estrogen-dependent unit; clinicians should take into account these cyclic variations during examination of subjects affected by symptoms of eye dryness.
By the way, did you notice how thorough those methods were... no fewer than 9 different testing methods (1 for symptoms, 8 for clinical signs). I am definitely getting a reprint of this study which hopefully will be generous with data on how results varied amongst the different markers.
Note that the study lead (Dr. Versura) had a previous publication about this in the same journal back in 2005:
Menopause and dry eye. A possible relationship.
...In post-menopausal women endocrine changes join the aging effects in the pathogenesis of dry eye, but still it remains controversial whether estrogen or androgen deficiency or their imbalance impair ocular surface function. Another questionable issue concerns the efficacy of hormonal replacement therapy in the amelioration of dry eye symptoms and recovery of tear function, since the scientific literature stands in between a therapeutic or a promoting effect of eye dryness. ...estrogen or androgen-based eye drops represents a promising innovative treatment based upon important scientific rationale.