Corneal arcus signals risk of incident CVD in Asian men
The presence of corneal arcus in Indian and Malay men appears to be associated with the risk of incident cardiovascular disease (CVD), independent of serum lipids and traditional CVD risk factors, reports a team of Singapore-based researchers.
Findings of the present study highlight the clinical significance of corneal arcus with respect to its association with increased CVD risk, researchers said, adding that eye care professionals should refer individuals presenting with arcus deposits for further CVD risk assessments and prevention programmes.
In the study, researchers followed for 6 years 3,637 Indian and Malay adults (mean age 56 years; 46 percent male) without CVD history at baseline and found that 208 (5.7 percent) developed CVD (myocardial infarction, angina pectoris or stroke), the primary study outcome. [Am J Ophthalmol 2017;183:99-106]
Incident CVD occurred with greater frequency among participants with corneal arcus than among those who did not (7.5 vs 4.9 percent). Multivariable logistic regression models showed a significant association between corneal arcus and incident CVD (adjusted odds ratio [OR], 1.52; 95 percent CI, 1.07 to 2.16).
When analysis was stratified by sex, the association was seen in men (adjusted OR, 1.73; 1.12 to 2.67) but not in women (adjusted OR, 1.05; 0.56 to 1.97). Researchers noted that this finding was independent of key confounders, including CVD risk factors and serum lipids, and consistent across both ethnicities and age groups.
“Other longitudinal findings in Caucasians have not shown consistent results. For example, the Framingham Heart Study found no significant associations of baseline corneal with incident CVD and coronary heart disease after adjusting for age and gender, while others have reported that baseline corneal arcus was independently associated with incident CVD only in younger men (<50 years),” they noted. [Am J Cardiol 2009;103:64-66]
Researchers explained that the discrepancy may be explained by the differences in CVD risk factors and outcomes between Asian and Caucasian populations. Furthermore, they acknowledged the possibility that the present study did not have enough participants in the <50 years age group to observe potentially significant differences between older and younger people.
While the mechanisms underlying the relationship between corneal arcus and CVD remain uncertain, corneal arcus is believed to reflect asymptomatic subclinical atherosclerosis that is not yet clinically manifested in patients. In recent literature, arcus deposits have been suggested to not just be a marker of elevated lipid levels but also an indicator of proatherogenic changes in vessels. [Am J Ophthalmol 2011;152:864-871.e861]
One important caveat to interpreting the current findings is the self-report nature of the CVD assessment, which increases the risk of recall and other biases, researchers noted.
Additional research is warranted to investigate the specific associations between corneal arcus and exact CVD subtypes, they added.