We read the recently published study entitled “Effect of randomized lipid lowering with simvastatin and ezetimibe on Cataract Development”. The investigators report a 44% lower risk of incident cataract development in the treatment arm of the study. The role of statins in the development of cataracts has been debated for years with studies reporting a deleterious, neutral, or protective effect.

An important point, which seemed to be overlooked in this study, was that the treatment group received ezetimibe, which was also a cholesterol-lowering agent, along with simvastatin. Attributing the observed effect solely to the statins might have been inaccurate. A concomitant use of erythromycin and simvastatin was associated with greater risk of cataract presumably because of significant increase in simvastatin bioavailability. Therefore, it would have been feasible to compare serum lipid profile especially low-density lipoprotein in patients, who developed cataract to those who did not. In addition, the study enrolled elderly participants (mean age of 68 years), where significant percentage of them may have suffered from varying degrees of lenticular opacity or they have already had cataract surgery before their enrollment. Likewise, patients with other types of cataract such as traumatic cataract had to be excluded. Unfortunately, the patients were not evaluated before enrollment, which as stated by the investigators is a major limitation, precluding the possibility of evaluation of cataract progression instead of incident cataract as the end point of the study. In view of the inconsistency of cataract diagnosis between different observers, lens opacities classification system III as an economical and effective method for an objective grading of cataract, could have been used. A more sophisticated method for objective grading of cataract is Scheimpflug imaging for lens densitometry, which is recommended for documenting progression of cataract opacities in longitudinal studies and clinical trials. Different mechanisms have been proposed for different types of senile cataract. Oxidative stress is believed to contribute in the pathogenesis of nuclear sclerosis. Classification of cataract type might have helped in determining if the potential benefit of statins lies in their anti-inflammatory activity.