Dermatologic vasculature diseases as a risk factor of subconjunctival hemorrhage

To evaluate the relationship between subconjunctival hemorrhage (SCH) and dermatologic vasculature diseases (DVDs) via the national health insurance research database (NHIRD) of Taiwan. This retrospective cohort study used data from the NHIRD for the 2009 to 2013 period. Patients diagnosed with DVDs were enrolled in the study group, and a propensity score-matching population was selected as the control group after exclusion. The main outcome was set as the development of SCH in both groups. Multivariable Cox regression analysis and survival analysis were performed to estimate the adjusted hazard ratio (aHR) and cumulative probability of SCH. A total number of 3426 patients were enrolled and split equally into the study and the control groups. There was no prominent difference between the age, gender, urbanization, income level, systemic co-morbidities, and ocular diseases between the two groups after matching. During the whole study period, 131 patients in the study group and 98 patients in the control group developed SCH with a significant higher aHR of 2.69 in the study group (p < 0.05). In the survival analysis, the study group also demonstrated a higher cumulative probability of developing SCH than the control group throughout the study period (p = 0.02). In conclusion, the presence of DVDs may be a risk factor for the development of SCH.