Homocysteine and risk of age‐related macular degeneration: a systematic review and meta‐analysis

Abstract

There is still no agreement on total plasma homocysteine (tHcy) role in age-related macular degeneration (AMD), the leading cause of new blindness in industrialized countries. We performed a systematic review and meta-analysis of the published data on the correlation between tHcy and AMD. MEDLINE/PubMed and ISI Web of Sciences searches were performed according to MOOSE guidelines. Case-control studies were eligible for inclusion. Participants and controls were AMD patients and subjects without AMD. The main outcome measure was wet AMD. Homocysteine level was the main exposure variable. Data were pooled using a random-effects model. Twelve case-control studies were identified: 10 assessed wet AMD, four dry AMD, one early AMD, one late AMD, and one any AMD. As for wet AMD, there was a total of 453 cases and 514 controls. Mean tHcy was on average 1.1 μmol/l (95% confidence interval [CI] = 0.96-1.25) greater in wet AMD cases, but there was evidence of extreme between-study heterogeneity (p < 0.001, I = 91.8%). In a model homogenous for age, including six wet AMD studies (214 cases, 274 controls), mean tHcy was on average 0.58 μmol/l (95% CI = 0.35-0.73) greater in the case group, a not statistically significant result (p = 0.144) associated with moderate heterogeneity (I = 39.2%). Our meta-analysis indicates that there is some weak evidence that increased tHcy might be associated with wet AMD; however, this result should be interpreted cautiously, because of a marked between-study heterogeneity and the possible effect of publication bias. Future studies, preferably of cohort design, are necessary before any firm conclusions on the putative role of increased tHcy on AMD can be drawn.

Advances in Age-related Macular Degeneration Understanding and Therapy

“…Previous attempts to identify serum biomarkers (C-reactive protein, homocysteine, and lipids) to identify patients with AMD and that correlate with disease progression yielded inconsistent data. 8 , 178 – 180 More recently, researchers have looked into more systematic and unbiased approaches of finding biomarkers through metabolomics. Metabolomics is the study of all the metabolites (metabolome), the small molecule “fingerprints” of cellular processes.…”

Biometric Alterations of Mouse Embryonic Eye Structures Due to Short-Term Folic Acid Deficiency

“…61 In elderly, FAD maybe due not only to low intake of FA but also to other circumstances (bad absorption, alcoholism, medication, etc.). Optic neuropathy [62][63][64] and macular degeneration 65,66 are related to FAD.…”

Implication of Hyperhomocysteinemia in Blood Retinal Barrier (BRB) Dysfunction

“…Several clinical studies suggested its involvement to both neuronal and vascular diseases of the retina such as; central retinal venous [ 31 , 32 ], retinal artery occlusion [ 33 , 34 ], glaucoma [ 35 ], and corneal pathologies and cataracts [ 36 , 37 , 38 ]. Furthermore, elevated Hcy has been suggested as a risk factor and a biomarker for the most common retinal diseases resulting in loss of vision worldwide such as DR [ 39 , 40 , 41 , 42 , 43 , 44 ] and AMD [ 45 , 46 , 47 , 48 ].…”