Photo Credit: Melitas

Sociodemographic factors and patient characteristics raise the risk for corneal hydrops in keratoconus and lower the odds of corneal crosslinking.

In patients with unstable keratoconus, several sociodemographic and medical factors independently increased the odds of developing acute corneal hydrops, including Black race, public health insurance coverage, obesity, and developmental delay, researchers reported in PLOS One.

“Moreover, male sex, Black race, and public health insurance coverage each independently reduced the odds of receiving CXL [corneal crosslinking] in those with unstable keratoconus at our institution,” wrote Levi N. Kanu, MD, and colleagues.

The retrospective study included 762 patients with unstable keratoconus diagnosed at Mass Eye and Ear between January 2016 and October 2022. The researchers compared sociodemographic, medical, and ocular characteristics of 113 patients who developed hydrops (case patients) with those of 649 patients who did not and were considered control patients.

Sociodemographic & Other Factors

According to the findings, hydrops disproportionately affected patients who were Black (27.6% of the hydrops group vs 14.6% of the control group), unemployed (22.4% of the hydrops group vs 12.5% of the control group), and/or covered by public health insurance plans (50.4% of the hydrops group vs 27.7% of the control group).

BMI was also higher in patients who developed hydrops, by an average of 34.1±10.0 compared with 29.2±8.1 in control patients. In addition, patients with hydrops had higher rates of developmental delay (17.7% vs 3.4% in control patients), atopy (48.9% vs 30.4% in control patients), sleep apnea (9.7% vs 1.2% in control patients), and eye rubbing (85.5% vs 67.7% in control patients).

Regression Analysis Results & CXL Outcomes

In a stepwise multivariable logistic regression analysis of risk factors for hydrops, odds ratios for incident hydrops were 16.42 with developmental delay, 2.10 with Black race, 2.06 with public health insurance coverage, and 1.05 with high BMI, the study found.

“A large proportion (92.1%) of those seen with a diagnosis of unstable keratoconus underwent CXL during the study period,” Dr. Kanu and colleagues wrote. “Those who did not receive CXL were more likely to be of Black race, have [a] higher no-show rate, have public insurance, and live in an area of higher (worse) area deprivation index.”

Odds ratios for CXL were 0.34 with male sex, 0.37 with public health insurance, and 0.39 with Black race.

“Special attention is warranted when caring for patients within these subpopulations with unstable keratoconus, and further study into the mechanisms of these associations is warranted,” the researchers wrote.