Findings from a study recently published in the Journal of Clinical Medicine evaluated whether there is an increased propensity for systemic conditions in patients with both age-related macular degeneration (AMD) and glaucoma.
Give me some background.
The concomitance of two separate ophthalmic diseases in a single patient warrants investigation into the potential for underlying factors that may predispose patients to clinical illness.
In this case of AMD and glaucoma: As both leading causes of vision loss, understanding the prevalence of non-ophthalmic systemic disease associated with the two may be useful to predict and manage a patient’s overall health.
- That being said: Previous research on concurrent AMD and glaucoma has primarily focused on their impact on patient quality of life.
Bring it back to this study.
Consequently, a research team from the University of Carolina, Augusta University, and University of Texas-Rio Grande Valley sought to fill the gap in current knowledge on the association of systemic disease in patients with both AMD and glaucoma.
Details, please.
In this retrospective study, investigators performed a large data set review of patients who presented to the University of North Carolina between April 2004 and June 2018.
They organized these patients into four groups based on international classification of diseases (ICD) codes:
- Glaucoma only (5,243 patients)
- AMD only (6,726 patients)
- Glaucoma and AMD (402 patients)
- Cataracts only (25,450 patients)
- This cohort was used as an age-matched control
The prevalence of systemic disease was calculated for each group and compared.
Findings?
Heart failure (HF) and dementia had a statistically higher prevalence in patients with both glaucoma and AMD compared to those with glaucoma alone (HF: p = 0.036; dementia: p = 0.024) and cataracts alone (HF: p = 0.003; dementia: p = 0.036).
There was also no significant difference observed in terms of ethnicity and gender between the different disease groups (p > 0.05).
Expert opinion?
Given that both AMD and glaucoma are age-related conditions, investigators noted that the prevalence of HF seen in this patient population may be attributed to an increased number of age-related cardiovascular risk factors.
They added that ocular and systemic inflammation also likely play a role in the association between HF, dementia, glaucoma, and AMD.
Tell me more.
Keep in mind: HF can lead to decreased cerebrovascular blood flow, which has been associated with dementia and can lead to reduced ocular perfusion.
- Meaning: This results in ischemia in the eye, followed by reperfusion, which may cause inflammation that, either by itself or in addition to chronic ongoing inflammation could lead to the development and progression of glaucoma and AMD.
Further: A low level of chronic systemic inflammation may lead to the development and progression of HF.
- Meaning: This may cause a “state of increased pro-inflammatory cytokines and other inflammatory molecules circulating throughout the body which could trigger dysregulation of mechanisms responsible for homeostasis of the immune system in immune-privileged tissues—like the brain and retina.”
Limitations?
These included:
- The study’s time frame (2004-2018) included the 2015 transition to the ICD-10 classification system, which may have led to inconsistencies between classifications.
- Only patients with primary glaucoma types were included so as to prevent confounding from systemic diseases that may cause secondary glaucoma.
- Only aggregate data was analyzed; as such, this study did not account for the course, severity, or causes of ophthalmologic conditions and comorbidities.
- There were discrepancies between the total for race, age, and sex because some charts lacked demographic data.
Take home.
These findings suggest that both AMD and glaucoma individually indicate a higher rate of comorbidities than age-matched controls.
- In fact: Patients with concomitant AMD and glaucoma demonstrated a distinctly higher prevalence of heart failure and dementia than those with either disease alone.
However: The underlying association and pathologic mechanisms behind these associations warrant further investigation to improve the overall health management and prognostication for these patients.