Patients with asthma in this study had a higher prevalence of cataract than those without the disease. Photo: Joseph Sowka, OD. Click image to enlarge.
The likelihood of cataract development is quite high with advanced age, and several factors are known to accelerate its development, chief among them UV light exposure, history of smoking and diabetes. However, some researchers believe cataracts and asthma could also be related, due to inflammatory pathways. As a common chronic inflammatory disease, asthma involves a lot of cells and cellular components of the respiratory system. An analysis of a representative sample of the US population found that asthma was a significant risk factor for cataract and vice-versa.
The cross-sectional study in BMC Ophthalmology included 40,457 participants 40 and older in the National Health Interview Survey over a 10-year period. The researchers assessed asthma and cataract status through patient questionnaires. The researchers controlled for age, sex, ethnicity, education level and marital status and then further adjusted by including high cholesterol, diabetes, hypertension, smoking status and alcohol consumption.
After adjusting for these potential confounding covariates, individuals with asthma had a higher prevalence of cataract than those without asthma (29% vs 26%), and those who had asthma had 40% higher odds of cataract compared with those without. When viewing asthma as the outcome, participants who had cataract had 36% higher odds of asthma compared with those without after adjusting for the potential confounding covariates.
The researchers noted in their paper, “Since our study was a cross-sectional designed study, causal relationship between asthma and cataract could not be determined.”
They concluded that more studies are needed to confirm their findings and illustrate the possible mechanisms that underlie the relationship between asthma and cataract.
Li W, Wang B. Cross-sectional study of the association between asthmas and cataract among 40 years and older in the USA. BMC Ophthalmol. August 10, 2022. [Epub ahead of print].