Psoriasis Raises Retinal Vein Occlusion Risk For Those With Diabetic Retinopathy

Psoriasis can increase the risk of developing retinal vein occlusion (RVO) among patients who already have diabetic retinopathy, according to research published in Retina.

Prior research has indicated that diabetes mellitus (DM) nearly doubles the risk of RVO, and that patients with psoriasis are more likely to develop DM.

Researchers in Korea examined records from 2009 to 2012 from the Korean National Health Insurance Service Claims Database universal healthcare system and national health screening data. Patients older than 20 years who had been diagnosed with type 2 DM based on that data were included in the study. The 2,570,846 participants had not been diagnosed with RVO before, or during the index year, through 2018. The investigators compared individuals who received treatment at an outpatient clinic following diagnosis of psoriasis (n=23,725) with the control group of remaining patients.

Patients with psoriasis were more likely to be older, men, and current smokers compared with the control individuals. They were more likely to have hypertension, dyslipidemia, and end-stage renal disease compared with the other group.

Individuals who developed RVO (n=42,885) were more likely to be women and older. They were more likely to regularly exercise and not drink or smoke. They more frequently had hypertension, dyslipidemia, and end-stage renal disease.

RVO was more common among diabetic patients with psoriasis compared with individuals without psoriasis (incidence rate 3.14 per 1000 person-years vs 2.44 per 1000 person-years).

With multivariable Cox proportional models and adjustments for covariates, the researchers found that patients with psoriasis were at higher risk of developing RVO compared with control individuals (hazard ratio 1.216 95% confidence interval 1.11-1.33). 

“The precise mechanisms underlying the association between psoriasis and RVO remain unclear. However, it is hypothesized that the inflammatory state and increased vascular complications observed in psoriasis patients may contribute to the occurrence of RVO,” the study authors explain. “These shared pathogenic mechanisms provide a plausible explanation for the association.”

Limitations of this study include a basis of definitions of psoriasis and retinal vein occlusion on claims data and lack of consideration of severity of disease or use of medications.