Common cardio drugs may improve PDT outcomes

By Cheryl Guttman

Fort Lauderdale - Concurrent treatment with antihyperlipidemic statin therapy or beta-blockers appears to be associated with improved visual outcomes among patients undergoing verteporforin (Visudyne) PDT for treatment of age-related macular degeneration (AMD).

Reseachers at the West Virginia University Eye Institute performed a chart review of 76 ARMD patients treated for predominantly classic CNV.
They extracted data concerning the presence of hypertension, diabetes mellitus, and hypercholesterolemia along with use of ACE inhibitors, calcium channel blockers, beta-blockers, statins, and nonsteroidal anti-inflammatory drugs.

The review showed that patients were almost equally divided between having stable or increased vision (zero to three line change) or vision loss (loss of one or more line), during a six month follow-up.

However, there was a statistical trend for better outcomes in the subgroups of patients receiving statins or beta-blockers. Vision was stable or increased in 13 (68.4%) of 19 patients being treated with a statin agent and in 7 (70%) of 10 eyes of patients on a beta-blocker.

"These are interesting findings. Although the follow-up encompasses the period post-PDT, when the rate of visual change is likely to be greatest, it remains short and our population is relatively small.

"We hope to continue this study and add data from more patients to see if these preliminary findings hold out and show statistical significance for the suggested associations," said Jason D. Givan MD, lead author of the poster and a recent graduate of the West Virginia University School of Medicine.

The study group included 50 patients with a diagnosis of hypertension, 11 with diabetes mellitus, and 19 with hypercholesterolemia /hyperlipidemia.
ACE inhibitors and calcium channel blockers were each being used by 18 patients, and 27 patients were taking NSAIDs. Use of any of those three classes of medications as well as all of the medical diagnoses were associated with vision outcomes similar to those observed in the overall population.

Dr Givan noted that the medical diagnoses and medication groups chosen for inclusion in the study were of particular interest since there is epidemiological evidence to show that the causal pathways for AMD and cardiovascular disease share risk factors, including hypertension and hypercholesterolemia.

In addition, studies report that patients with AMD have higher serum total cholesterol levels compared to unaffected controls. The researchers proposed various hypotheses accounting for the potential beneficial effect of statin and beta-blocker therapy on clinical outcomes.

"By lowering cholesterol, statin therapy may decrease lipid deposition in the CNV membrane. Additionally, the effect of beta-blockers might be secondary to their action of lowering systemic arterial blood pressure. Interestingly, however, 18 patients received calcium channel blockers and their visual outcomes were numerically worse than the overall study population," Dr Givan said.

Monique Leys MD, senior author and Assistant Professor of Ophthalmology, West Virginia University Eye Institute, added that beta-blockers might have a particular beneficial effect on the RPE.

"Beta blockers have been used to treat patients with central serous choriodopathy and have been shown to have a positive effect on the electro-oculogram, which is a measure of RPE function," she said.

In recent years, large randomised clinical studies and population studies have shown that statin therapy protects against primary and secondary heart attacks and stroke.
Recent studies also indicate that statins may have beneficial effects beyond simply lowering serum cholesterol. For example, a number of recent studies suggest a reduced risk of dementia and Alzheimer's disease among those taking statins.

Beta-blockers have been a mainstay of treatment for heart disease for decades. Numerous large multicentre studies have confirmed the cardioprotective effects of these agents in at-risk patients.