A recent study published in Ophthalmology investigated the potential protective role of omega-3 fatty acids in age-related macular degeneration (AMD).
Give me some background.
Previous studies and clinical trials have reported inconsistent findings regarding the protective impact of omega-3 polyunsaturated fatty acids (PUFAs) on AMD—potentially due to the limitations of these investigations.
Consequently: A research team from Singapore sought to clarify whether increasing plasma omega-3 levels through dietary modifications could provide a practical and noninvasive approach to preventing and treating AMD.
Now, talk about the study.
In this prospective cohort study, investigators included individuals of European descent from the UK Biobank with recorded plasma omega-3 and docosahexaenoic acid (DHA) measurements.
- Quick refresh: The UK Biobank is a large-scale biomedical database that contains in-depth, de-identified genetic and health information from half a million UK participants.
Subsequently: The researchers performed Mendelian randomization (MR) analyses using genome-wide association study (GWAS) study data on plasma levels of omega-3 and:
- DHA (UK Biobank, n=115,006)
- AMD (dry, wet, and any; FinnGen, n=208,690 to 209,122)
Main outcome measure: The risk of developing AMD.
Findings?
Of the 258,350 AMD-free individuals, 5,068 (1.9%) developed AMD over the 12.9-year follow-up period.
Specifically: Higher plasma levels (in mmol/L) of omega-3 (hazard ratio [HR] 0.80, 95% confidence interval [CI] 0.72-0.95, P=0.006) and DHA (HR 0.65, 95% CI 0.44-0.96, P=0.029) were associated with lower risks of being diagnosed with AMD.
MR analyses demonstrated causality between genetic predisposition to higher plasma omega-3 levels and a lower risk of:
- Dry AMD (OR 0.83, 95% CI 0.73-0.96, P=0.10)
- Wet AMD (OR 0.76, 95% CI 0.65-0.88, P<0.001)
- Any AMD (OR 0.82, 95% CI 0.74-0.92, P<0.001)
Anything else?
Likewise, genetic predisposition to higher plasma DHA levels was causally associated with a lower risk of:
- Wet AMD (OR 0.79, 95% CI 0.65-0.96, P<0.001)
- Any AMD (OR 0.84, 95% CI 0.72-0.98, P<0.001)
However: No significant interaction was found between omega-3/DHA levels and AMD genetic risks (all P>0.05).
Take home.
These findings suggest a protective effect of omega-3 and DHA on AMD, supporting the need for further clinical trials to test their efficacy in AMD prevention and treatment.
Next steps?
Further research is required to elucidate whether omega-3 is effective for early AMD and geographic atrophy (GA) separately, the study authors noted.
As genotyping and other biomarkers become more widespread, personalized recommendations based on genotype data may allow for precision public health in AMD prevention, they added.