Calcium channel blocker use linked to 39% higher odds for glaucoma, no effect on IOP
Click Here to Manage Email Alerts
Key takeaways:
- CCB users had 39% higher odds of glaucoma on average, as well as thinner inner retinal thickness, vs. non-users.
- There was no effect on IOP, suggesting another mechanism tying glaucoma to CCB use.
Calcium channel blocker use was associated with an average 39% higher odds of glaucoma, as well as thinner inner retinal thickness, in a cross-sectional study of UK Biobank data.
The study, published in JAMA Ophthalmology, also found no relationship between calcium channel blocker (CCB) use and IOP, suggesting an IOP-independent mechanism of glaucomatous neurodegeneration could be involved, researchers wrote.
No causal relationship was found, but the study of 427,480 adults adds large-scale evidence to previously reported adverse associations between CCBs and glaucoma. Its results indicate that CCB replacement or withdrawal may be warranted in glaucoma that is resistant to other treatment, researchers added.
The study included adults aged 37 to 73 years and analyzed their CCB use in relation to glaucoma status, IOP or OCT-derived inner retinal layer thicknesses, depending on what they had complete data for. Of all participants, 7.8% were CCB users, 89% of whom had hypertension.
Participants included in the study had a median age of 58 years and 54.1% were women. They were also 94.8% white, which researchers highlighted as one of the study’s limitations.
CCB use was associated with greater odds of glaucoma (OR = 1.39; 95% CI, 1.14-1.69) after adjustment for sociodemographic, medical, anthropometric and lifestyle factors. Other antihypertensive agents, including diuretics, renin-angiotensin system inhibitors and systemic beta-blockers, showed no association with glaucoma.
Researchers examined two measures of inner retinal thickness: macular ganglion cell-inner plexiform layer (mGCIPL) and macular retinal nerve fiber layer (mRNFL). CCBs were associated with thinner mGCIPL (–0.34 m; 95% CI, –0.54 to –0.15) and mRNFL (–0.16 m; 95% CI, –0.3 to –0.02) thicknesses.
On a population level, the reported effect estimates for mGCIPL and mRNFL thicknesses were equivalent to the average difference between participants separated by 4 years in age, researchers wrote.
There was no association between CCB use and IOP (–0.01 mm Hg; 95% CI, –0.09 to 0.07). Researchers wrote that CCBs’ association with glaucoma “may act via IOP-independent mechanisms,” but acknowledged limited data collection that may obscure the full effect of CCBs on IOP.
Researchers called for further studies to “probe potential underlying biological mechanisms” driving glaucoma in CCB users. More investigation is also warranted to determine whether the relationship is causal.
Perspective
Back to Top
Today’s doctors must navigate a complex battlefield of comorbidities with the understanding that medication for one condition may increase risk for another.
CCBs — commonly used to treat high blood pressure — can increase glaucoma risk by 39%. Retinal thickness was also thinner in users of this medication, but the mechanism was IOP-independent. The authors suggested neurodegeneration could be involved.
These findings are simultaneously worrisome and a cause for hope. If a drug can accelerate neurodegeneration, this may provide clues on how to prevent or reverse disease as well. More immediately, it allows us to caution patients who are glaucoma suspects taking these medications of the potential risks.
It is also our duty to inform other health care providers of CCB-related complications. This is a two-way street, so we must be cognizant that ocular drugs could negatively impact other aspects of well-being. Remember that evidence-based science takes time to reach publication, so if a patient complains of a previously unknown side effect, believe them.
Whenever possible, a healthy lifestyle that includes a balanced diet, exercise, sleep hygiene, stress reduction, and addressing the modern epidemic of depression and loneliness should be encouraged, due to the overall positive impact with minimal drawbacks.
Collapse
Read more about
Click Here to Manage Email Alerts