Early-Stage Hypertension Linked to Increased Prevalence of Retinal Atherosclerosis

Retinal atherosclerosis may begin to develop in individuals with elevated blood pressure or stage 1 hypertension, according to research results published in the American Journal of Hypertension.

Through a retrospective observational analysis, researchers sought to evaluate the relationship between blood pressure classification — based on the 2017 American College of Cardiology (ACC)/American Heart Association (AHA) blood pressure guideline — and the prevalence of retinal atherosclerosis by using a nationwide Japanese claims database. Specifically, researchers wanted to determine if this guideline could stratify risks related to blood pressure elevation in the general population.

Data from the JMDC Claims Database for 373,766 patients from 2005 to 2020 were extracted and reviewed. After applying exclusion criteria, 280,599 patients were included in the study.

At baseline, participants were classified as having normal blood pressure (n=159,524), elevated blood pressure (n=35,603), stage 1 hypertension (n=54,795) or stage 2 hypertension (n=30,677). Patients in the latter 3 groups were generally older and more likely to be men compared with those in the normal blood pressure group. Patients in these 3 groups also had a higher body mass index (BMI), waist circumference, fasting plasma glucose, serum low-density lipoprotein cholesterol (LDL-C) and triglyceride levels, and lower serum high-density lipoprotein cholesterol (HDL-C) levels.

Cigarette smoking and alcohol consumption were also more common in these groups.

Of these patients, 94.0% had normal retinoscopy findings; 6.0 % and 0.5%, respectively, had retinal atherosclerosis defined as Keith-Wagener-Barker system grade of 1 and greater and grade 2 and greater. The presence of retinal atherosclerosis increased stepwise from 3.2% in the normal blood pressure group to 18.7% in the stage 2 hypertension group. Grade 2 and greater retinal atherosclerosis also increased from 0.2% in the normal blood pressure group to 2.1% in the stage 2 hypertension group.

Results of a multivariable logistic regression analysis demonstrated that elevated blood pressure, stage 1 hypertension, and stage 2 hypertension are all associated with a higher prevalence of retinal atherosclerosis (odds ratios [ORs], 1.30, 1.71, and 4.10).

Investigators also conducted 4 sensitivity analyses. A multivariable logistic regression analysis including 327,400 patients following multiple imputation for missing values indicated that elevated blood pressure and stage 1 and 2 hypertension were all associated with a higher prevalence of retinal atherosclerosis compared with normal blood pressure (ORs, 1.29, 1.67, and 3.70). In 92,121 patients without cardiovascular disease risk factors, this analysis showed that all 3 non-normal blood pressure groups were also associated with higher retinal atherosclerosis prevalence (ORs, 1.34, 1.79, and 4.42).

This association between blood pressure category and retinal atherosclerosis was noted in all subgroups, even when stratified by age or sex.

Finally, elevated blood pressure and stage 1 or 2 hypertension are also associated with higher prevalence of retinal atherosclerosis with Keith-Wagener-Barker system grade 2 and greater vs normal blood pressure.  

Study limitations include the use of a single blood pressure measurement that may not reflect a patient’s blood pressure phenotype, the possibility of unmeasured confounders, and selection bias in the study population included. Additional research is necessary to determine if results are generalizable outside of the study population.

“Elevated [blood pressure] and stage 1 and stage 2 hypertension…were associated with a higher prevalence of retinal atherosclerosis compared with normal [blood pressure] in a large population,” the researchers wrote. “Our results suggest that atherosclerosis could start even in individuals with elevated blood pressure or stage 1 hypertension.”

“These results may contribute to the development of an optimal treatment strategy for elevated [blood pressure] and stage 1 hypertension defined by the 2017 AAC/AHA [blood pressure] guideline,” they concluded.

Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.

Reference

Matsuoka S, Kaneko H, Yano Y, et al. Association between blood pressure classification using the 2017 ACC/AHA blood pressure guideline and retinal atherosclerosis. Am J Hypertens. Published online May 19, 2021. doi:10.1093/ajh.hpab074