The effects of pregnancy on disease progression of retinitis pigmentosa.

Abstract

Purpose: Retinitis pigmentosa (RP) is the most common diagnosis in the ophthalmic genetics' clinic. Women with RP are often diagnosed during their reproductive years, posing significant challenges for family planning. The effects of pregnancy on RP progression is a frequently unanswered concern for these patients.

Design: Retrospective cohort study.

Subjects: Women who attended Moorfields Eye Hospital (London, UK) and met the following inclusion criteria were included in this study: (i) had their most recent visit at 30 years old or more, (ii) were diagnosed with RP, (iii) had information in their medical records about having had children, and (iv) were found to have biallelic rare or likely disease-causing variants in USH2A.

Methods: The cohort was divided into parous and nulliparous, and multivariate Cox regressions adjusting for multiple confounding effects was performed. A further analysis also included number of children as a variable.

Main outcome measures: RP severity criteria based on visual acuity (VA) and ellipsoid zone (EZ) width, and national registration of sight impairment.

Results: 142 women were included in the study, 98 parous (69%) and 44 nulliparous (31%). In the parous group, 21% had cystoid macular oedema (CMO) requiring treatment and 46% had cataracts or were pseudophakic, versus 18% with CMO and 59% with cataracts in the nulliparous. Women had a median of 2 children. A significant association was only found in parous women having 3.04 (1.23-7.48) times increased risk of having VA worse than LogMAR 0.7 than nulliparous (p= 0.016), after adjusting for baseline age, phenotype, cataract status, and CMO.

Conclusions: This is the first large-scale objective study analysing the effects of pregnancy in genetically-confirmed women with RP. Women with USH2A-associated RP who had children appeared to have 3.04 times the risk of reaching VA below 6/24 than those who did not have children. It is possible that other factors besides retinal degeneration are affecting central vision and causing this increased risk. A significant association between faster or slower EZ loss and pregnancy was not present in our cohort. We believe these findings will be relevant to all women with RP considering starting a family; although further studies are needed.