Astigmatism’s Role in Myopia and its Management Unclear

Myopia and astigmatism are both quite common, although myopia—especially high myopia—comes with increased ocular complication and visual impairment risk, while astigmatism is mainly only implicated in refractive concerns. Some research indicated that prevalence and severity of astigmatism increased in response to significant lifestyle change following the COVID lockdowns, with more time spent indoors and on near activities. This suggests astigmatism may be influenced by similar lifestyle factors as myopia. Photo: Cory Collier, OD. Click image to enlarge. New research published in Ophthalmic and Physiological Optics outlines the findings of researchers who conducted a scoping review to elucidate what kinds of relationships may exist between these two refractive errors. Included was a total of 47 studies, with two aims: (1) to explore myopia prevalence and onset as they relate to astigmatism and (2) investigate myopia control efforts in the presence of astigmatism. Of those included, 30 studies reflected the first goal and 17 the second; a majority of 31 studies were conducted in Asia. It was found that higher astigmatism prevalence was associated with myopia, with myopia progression and astigmatism potentially being related, but with limited research on the effects of uncorrected astigmatism on the course of myopia. There is also limited research on how astigmatism may influence effectivity of myopia control strategies, with much conflicting evidence.In the discussion section of their paper, the study authors elaborate on each of these categories and more specific findings. They outline also that 39 of the 47 studies included children only and the most common study types were longitudinal observational (13) and retrospective (14). They also note that more prospective research is needed in non-Asian populations, especially in myopia control interventions with astigmatism.Much of the disparity in conclusions on the relationship between myopia and astigmatism may be due to varying methods of measuring astigmatism, varying inclusion and exclusion criteria and differences in how myopia was defined, the authors noted. Many studies reported association between astigmatism and myopia progression, but only a few have observed an independent relationship between astigmatism in myopia progression, with none finding a causative role of myopia attributed to astigmatism.Another category involved studies evaluating if myopia is linked with increasing astigmatism, and some results indicated greater astigmatic progression to be linked with myopia, while others found no difference between those with stable or changing astigmatism.With myopia control, 13 investigations spanned this category, with most reporting on orthokeratology and atropine. One study found that in those wearing DIMS spectacles, individuals with astigmatism had greater myopia progression; this was not reported in those wearing only single vision lenses. Thus, this suggests the presence of astigmatism may hinder the efficacy of optical interventions for myopia control. One theory for this observation involves astigmatism affecting the uniformity of the peripheral blur induced by the lenses, reducing effectiveness, and the other is that changes in axial elongation and astigmatism may be interrelated and directly influenced by these optical interventions.With this in mind, the researchers relay that more research is needed on the role of uncorrected and corrected astigmatism on the efficacy of myopia control interventions. As they explain, “this information is needed to provide an evidence base to inform clinical decision-making and patient management plans for myopic children with astigmatism. Clinicians should be cautious in discussing the likelihood of success using optical interventions in patients with astigmatism until an evidence base has been established.” Click here for the journal source. Kearney S, Shah R, Vlasak N. The role of astigmatism in myopia development, myopia progression and myopia control. Ophthalmic Physiol Opt. 2025;00:1-19.This article was developed by the editorial staff in conjunction with experts in the field. In the process, AI may have been among the editorial tools used to meet the goals of human editors, who approved all content.