■ A population-based retrospective cohort study of patients with open-angle glaucoma (OAG) and angle-closure glaucoma (ACG) found a significantly higher all-cause mortality rate among those who had surgery vs those with a glaucoma diagnosis and no surgery, according to research published in Nature Scientific Reports. The study examined 16,210 elderly Korean patients (aged ≥60 years) diagnosed with glaucoma between 2003 and 2012. The cohort came from the Korean National Health Insurance Service-Senior database, which contains data on 558,147 elderly individuals randomly sampled from 10% of the approximately 5.5 million older South Koreans. The database lists information on age, sex, general health examinations, hospital and pharmacy visits, disease diagnoses, status, procedures, and prescribed medications.

The study cohort included 16,210 patients with glaucoma (mean age, 72.6 years). Among the study cohort, 487 patients underwent glaucoma surgery and 15,723 did not. The mean age of the overall cohort was 72.6 years, and the researchers noted that patients older than 70 years of age tended not to opt for glaucoma surgery. Individuals in the glaucoma surgery group were significantly younger than those in the glaucoma diagnosis group.

The authors analyzed for all-cause mortality and specific mortality causes and controlled for covariates. The adjusted risk for all-cause mortality associated with glaucoma surgery was an increase of 31% vs the glaucoma diagnosis-only group (adjusted HR, 1.31; 95% CI, 1.05-1.62; P=.014).The adjusted hazard ratio for mortality due to a neurologic cause was significant (HR=2.66; 95% CI, 1.18-6.00; P=.018), as were the adjusted mortality HRs for cancer and accident or trauma among surgery patients with ACG (HR 2.03) but not OAG (HR 4.00).

Previous studies have examined the association between glaucoma and neurologic disease with pathogenic mechanisms like neurotoxicity caused by amyloid-beta, tau protein, autophagy downregulation, dopamine depletion, and alteration of the hemodynamics of cerebral arteries with white matter lesions being targeted.

“Several experts have suggested a correlation between glaucoma and stroke ... Alzheimer’s disease and Parkinson’s disease are representative neurologic disorders that are reportedly associated with glaucoma,” wrote Lee et al. “In studies using brain magnetic resonance imaging, structural and functional alterations were observed in patients with glaucoma. These results support the hypothesis that glaucoma should be considered a central nervous system disorder.”

The authors concluded that their findings should encourage healthcare providers and patients to be vigilant following glaucoma surgery to reduce and prevent death. “It is important to detect and treat glaucoma early to minimize the need for surgical treatment,” the researchers added.