Corneal Arcus and Cardiovascular Risk Factors in Middle-Aged Subjects in Taiwan

Prevalence and associated factors of corneal arcus in the geriatric population; Tehran geriatric eye study

Purpose

To determine the age and sex-standardized prevalence of corneal arcus and its associated factors in a geriatric population.

Methods

This population-based cross-sectional study was conducted in 2019 in Tehran; the capital of Iran, using a multi-stage stratified random cluster sampling method. All participants underwent a detailed interview, blood pressure measurement, laboratory blood tests, and a complete ocular examination.

Results

Three thousand three hundred ten of 3791 invitees participated in the study (response rate: 87.31%). The mean age of the participants was 69.35 ± 7.62 years (60–97 years) and 1912 (57.76%) were female. Overall, the age and sex-standardized prevalence (95% CI) of corneal arcus was 44.28% (41.21–47.39). Based on the multiple logistic regression, the odds of corneal arcus were higher in men than in women (OR: 1.51; 95% CI: 1.14–2.00); in the age group ≥ 80 years compared to the age group 60–64 years (OR: 2.44; 95% CI: 1.68–3.53), and in retired people compared to employed individuals (OR: 2.05; 95% CI: 1.31–3.21).

Conclusion

The present study showed a high prevalence of corneal arcus in the geriatric population. Although various studies have reported a significant relationship between corneal arcus with blood lipid and glucose levels as well as blood pressure, these relationships were not found in the present study.

Is Corneal Arcus Independently Associated With Incident Cardiovascular Disease in Asians?

PURPOSE

To examine the longitudinal relationship between baseline corneal arcus (CA) and incident cardiovascular disease (CVD) in ethnic Indian and Malay adults in Singapore.

DESIGN

Population-based cohort study.

METHODS

Indian and Malay adults aged 40-80 years were recruited for baseline and 6-year follow-up visits between 2004-2009 and 2010-2015, respectively (follow-up response rate 73.9%). CA was assessed by ophthalmologists using slit-lamp biomicroscopy. The main outcome was self-reported incident CVD, defined as new myocardial infarction, angina pectoris, or stroke, which developed between baseline and follow-up. Multivariable logistic regression models assessed independent associations between baseline CA and incident CVD, adjusting for traditional CVD risk factors including age, sex, serum cholesterol, hypertension, diabetes, and smoking. We further conducted sex-stratified analyses to identify possible effect modifications.

RESULTS

Of the total 3637 participants (overall mean [SD] age: 56 [9] years, 46% male) with available follow-up data, without history of CVD at baseline, 208 (5.7%) incident CVD cases were reported. Participants with CA were more likely to have incident CVD (7.5%) than those without (4.9%). After controlling for traditional CVD risk factors, CA was independently associated with incident CVD (odds ratio [95% confidence interval]: 1.52 [1.07-2.16]) in adjusted models. In sex-stratified models, associations between CA and incident CVD were seen in men (1.73 [1.12-2.67]) and not in women (1.05 [0.56-1.97]).

CONCLUSIONS

CA is associated with incident CVD, independent of serum lipids and traditional CVD risk factors, in ethnic Malay and Indian men. Our finding suggests that CA is an additional observable indicator of CVD in men.

A population-based study of corneal arcus and its risk factors in Iran

PURPOSE

To determine the prevalence of corneal arcus, its risk factors, and its relationship to ocular and visual indices.

METHODS

In this cross-sectional study, 300 clusters were randomly selected from Shahroud in the north of Iran, using multistage sampling. A total of 20 people were invited to participate from each cluster. After enrollment, all optometric, biometric and ophthalmic exams were conducted on site.

RESULTS

Of 6311 people invited, 5190 (82.2%) participated in the study. The prevalence of corneal arcus was 23.3% (95% confidence interval, CI, 22.1-24.6), and 98.4% were bilateral cases. The prevalence of corneal arcus was higher in men (odds ratio, OR, 2.02, 95% CI 1.8-2.3, p < 0.001) and increased with age (OR 1.1/year, p < 0.001). In a multivariable-adjusted regression model, age (OR 1.1/year, p = 0.006), male sex (OR 1.30, p = 0.001), diabetes (OR 0.7, p < 0.001), smoking (OR 1.5, p = 0.003), outdoor activity (OR 1.4, p = 0.006), systolic blood pressure (OR 1.01, p = 0.012), and diastolic blood pressure (OR 0.99, p = 0.016) were significantly correlated with corneal arcus. Including biometric components in another model, corneal thickness (OR 0.99, p < 0.001), anterior chamber depth (OR 0.68, p < 0.001) and corneal radius of curvature (OR 1.59, p < 0.001) were significantly correlated with corneal arcus.

CONCLUSION

This study adds valuable information to the epidemiology of corneal arcus in Iran and the Middle East. In people aged over 60 years, nearly 50% of the study population had corneal arcus. Older age, male sex, smoking, and systolic hypertension were risk factors for corneal arcus. Corneal arcus was also associated with thin and flat corneas and shallow anterior chamber depth.

Corneal arcus is a sign of cardiovascular disease, even in low-risk persons

PURPOSE

To examine the association of corneal arcus to cardiovascular disease (CVD) in an adult, ethnic Indian population.

DESIGN

Population-based cross-sectional study.

METHODS

Population-based study of ethnic South Asian Indians 40 to 80 years of age in Singapore from June 2007 through March 2009. We obtained a 75.5% response rate (3397/4497). All participants underwent standardized interview and systemic and ocular examinations, followed by nonfasting blood sampling. Corneal arcus was detected using a standardized slit-lamp examination. The main outcome measure was CVD, defined from a self-reported history of previous myocardial infarction, angina, or stroke.

RESULTS

Corneal arcus, found in 1701 (50.1%) of 3397 participants, was associated with older age (odds ratio [OR], 3.07; 95% CI, 2.78 to 3.40; P < .001), male gender (OR, 2.17; 95% CI, 1.81 to 2.62; P < .001), higher levels of total cholesterol (OR, 1.14; 95% CI, 1.05 to 1.24; P = .002), hypertension (OR, 1.14; 95% CI, 1.05 to 1.24; P = .013), and cigarette smoking (OR, 1.59; 95% CI, 1.25 to 2.03; P < .001). Corneal arcus was associated with CVD (OR, 1.31; 95% CI, 1.02 to 1.7; P = .0038) independent of the above-named cardiovascular risk factors. Participants with low-risk Framingham scores were more likely to be associated with CVD if they had corneal arcus (men: OR, 2.02; 95% CI, 1.20 to 3.40; P = .008; women: OR, 2.78; 95% CI, 1.36 to 3.01; P < .001). Corneal arcus was associated with CVD independent of the Framingham score (men: Akaike information criterion, 1524.39 for Framingham Score and corneal arcus vs 1527.38 for Framingham Score alone; women: 1000.14 vs 1003.54, respectively).

CONCLUSIONS

Corneal arcus is associated with CVD, independent of risk factors in ethnic Indian adults, even in those at low risk for vascular disease.

Cardiovascular risk factors, inflammation, and corneal arcus: the singapore malay eye study

PURPOSE

To examine the relationship of corneal arcus with cardiovascular risk factors and inflammation in Malay adults living in Singapore.

DESIGN

Population-based cross-sectional study.

METHODS

A total of 3280 Malays aged 40-80 years (out of 4168 eligible participants; 78.7% response rate) had a standardized interview, systemic and ocular examinations, and laboratory investigations, including measurement of C-reactive protein (CRP), chronic kidney disease, and peripheral artery disease. Corneal arcus was defined from anterior segment images taken with a slit-lamp camera.

RESULTS

Corneal arcus was seen in 2345 out of 3260 participants who had anterior segment images (73.2%). After adjustment for age, gender, total cholesterol, serum glucose, and current smoking, many cardiovascular risk factors significantly associated with corneal arcus, including male gender (odds ratio [OR] 1.65, 95% confidence interval [CI] 1.27-2.03), older age (per 10 years, OR 4.49, 95% CI 3.91-5.15), higher body mass index (per kg/m(2), OR 1.02, 95% CI 1.00-1.04), higher levels of CRP (per 10 mg/L, OR 1.36, 95% CI 1.13-1.64), total cholesterol (per mmol/L, OR 1.21, 95% CI 1.11-1.32), low-density lipoprotein cholesterol (per mmol/L, OR 1.94, 95% CI 1.38-2.74), presence of peripheral artery disease (OR 3.85, 95% CI 1.29-11.5), chronic kidney disease (OR 1.14, 95% CI 1.03-1.38), and current smoking (OR 1.29, 95% CI 1.02-1.69).

CONCLUSIONS

This study confirms known associations of traditional cardiovascular risk factors with corneal arcus in an Asian population. Additionally, corneal arcus may be associated with systemic inflammatory markers, peripheral artery disease, and chronic kidney disease.