Exploring the Link Between Calcium Channel Blockers and Glaucoma: Findings from a UK Biobank Study

The use of pharmaceutical agents in medicine is often a delicate balancing act between their therapeutic benefits and potential side effects.

One such class of drugs, Calcium Channel Blockers (CCBs), has come under scrutiny due to its possible association with an increased risk of glaucoma.

This article delves into a detailed analysis of a cross-sectional study conducted within the UK Biobank, aiming to uncover the relationship between systemic CCB use and glaucoma, as well as related traits.

Understanding Calcium Channel Blockers

Calcium channel blockers are a group of medications primarily prescribed to manage hypertension, angina, and certain heart arrhythmias. They work by inhibiting calcium ions from entering cells in the heart and blood vessel walls, thereby relaxing blood vessels and reducing the heart’s workload. These drugs are widely used due to their effectiveness in treating cardiovascular conditions, but concerns about potential side effects, such as glaucoma, have emerged.

The Study Design

This population-based cross-sectional study, conducted using data collected between 2006 and 2010, involved participants from the UK Biobank.

The study aimed to analyze glaucoma status, intraocular pressure (IOP), and optical coherence tomography (OCT)-derived inner retinal layer thicknesses concerning systemic CCB use. The analysis took place in January 2023.

Key Findings

The study included a substantial sample of 427,480 adults, with a median age of 58 years, of whom 54.1% were women. Among the participants, 7.8% were CCB users. After adjusting for various sociodemographic, medical, anthropometric, and lifestyle factors, several significant findings emerged:

• Increased Odds of Glaucoma: CCB use was associated with a 39% higher odds of glaucoma (odds ratio [OR] of 1.39), compared to non-users. This suggests a potential adverse association between CCBs and glaucoma.
• Thinner Retinal Layers: CCB users displayed thinner macular ganglion cell-inner plexiform layer (mGCIPL) and macular retinal nerve fiber layer (mRNFL) thicknesses. These structural changes in the retina provide evidence supporting the link between CCB use and glaucoma.
• No Impact on Intraocular Pressure: Interestingly, CCB use did not affect intraocular pressure (IOP). This finding suggests that the association between CCBs and glaucoma may involve an IOP-independent mechanism, possibly related to neurodegeneration.

Conclusion and Implications

In this comprehensive study, the use of Calcium Channel Blockers was associated with a higher likelihood of glaucoma, as well as thinner inner retinal layer thicknesses. While a causal relationship has not been definitively established, these findings underscore the importance of further research into the potential side effects of CCBs.

Physicians should consider monitoring glaucoma progression in patients on CCB therapy and, if necessary, explore alternative treatments or withdrawal of CCBs to ensure optimal care for individuals at risk of or diagnosed with glaucoma. Overall, this study contributes valuable insights into the complex interplay between medication usage and ocular health.

reference link: https://jamanetwork.com/journals/jamaophthalmology/article-abstract/2809275