Effect of Topical Timolol and Betaxolol on Plasma Lipids in Indian Patients of Primary Open-Angle Glaucoma
369-376
Correspondence
Dr Rashmi Sharma. 216-A, Last Morh Gandhi Nagar Jammu, Tawi, Pin: 180004, J&K state, India. E-mail: drrashmi@india.com
Background: The β-blockers adversely affect plasma lipids.
Aim: To evaluate the effect of topical timolol and betaxolol on plasma lipids.
Setting and Design: The present prospective randomised single-blind parallel study was conducted in Postgraduate Department of Pharmacology and Therapeutics in collaboration with Postgraduate Department of Ophthalmology of a medical college.
Materials and Methods: Sixteen (23 eyes) and 12 (20 eyes) patients of primary open-angle glaucoma with intraocular pressure (IOP) more than 26 mmHg were randomised to receive timolol maleate 0.5% and betaxolol hydrochloride 0.5%, respectively, as one drop twice a day instillation for 12 weeks. Lipid profile and IOP of each patient were recorded at 0, 6 and 12 weeks. Plasma lipids were estimated by standard method using photoelectric colorimeter.
Statistical Analysis: Effects of the individual drug on study parameters were analysed by using student’s paired t-test, and inter-group comparison was done by using unpaired t-test. P-value ≤0.05 was considered statistically significant; 95% confidence intervals (CI) were calculated according to the standard procedures laid down.
Results: In the present study, topical timolol raised total cholesterol by 17.50 ± 2.69 mg% (p < 0.0001), LDL cholesterol by 16.27 ± 2.48 mg% (p < 0.0001), TG cholesterol by 14.56 ± 2.58 mg% (p = 0.0002), VLDL cholesterol by 2.91 ± 0.51 mg% (p = 0.0002), TC:HDL by 0.56 ± 0.07 (p < 0.0001), LDL:HDL by 0.47 ± 0.11 (p < 0.0001) and reduced HDL cholesterol by 1.68 ± 0.07 mg% (p = 0.035) after 12 weeks, while topical betaxolol produced insignificant effect on plasma lipids. Topical timolol and betaxolol lowered IOP by 13.05 ± 1.53 and 7.58 ± 0.90 mmHg, respectively, after 6 weeks and by 16.12 ± 1.67 and 8.535 ± 0.983 mmHg, respectively, after 12 weeks (p < 0.001).
Conclusions: In the present study, topical instillation of betaxolol was found to be superior to topical timolol with better safety profile (plasma lipids).