Clinical risk factors for age-related macular degeneration: A systemic review and meta-analysis

Centre for Vision Science, Queen's University Belfast, Northern Ireland, UK.
BMC Ophthalmology (Impact Factor: 1.02). 12/2010; 10(1):31. DOI: 10.1186/1471-2415-10-31
Source: PubMed


Age-related macular degeneration (AMD) is the leading cause of blindness in Western countries. Numerous risk factors have been reported but the evidence and strength of association is variable. We aimed to identify those risk factors with strong levels of evidence which could be easily assessed by physicians or ophthalmologists to implement preventive interventions or address current behaviours.
A systematic review identified 18 prospective and cross-sectional studies and 6 case control studies involving 113,780 persons with 17,236 cases of late AMD that included an estimate of the association between late AMD and at least one of 16 pre-selected risk factors. Fixed-effects meta-analyses were conducted for each factor to combine odds ratio (OR) and/or relative risk (RR) outcomes across studies by study design. Overall raw point estimates of each risk factor and associated 95% confidence intervals (CI) were calculated.
Increasing age, current cigarette smoking, previous cataract surgery, and a family history of AMD showed strong and consistent associations with late AMD. Risk factors with moderate and consistent associations were higher body mass index, history of cardiovascular disease, hypertension, and higher plasma fibrinogen. Risk factors with weaker and inconsistent associations were gender, ethnicity, diabetes, iris colour, history of cerebrovascular disease, and serum total and HDL cholesterol and triglyceride levels.
Smoking, previous cataract surgery and a family history of AMD are consistent risk factors for AMD. Cardiovascular risk factors are also associated with AMD. Knowledge of these risk factors that may be easily assessed by physicians and general ophthalmologists may assist in identification and appropriate referral of persons at risk of AMD.

Download full-text


Available from: Paul Mitchell,
  • Source
    • "AMD risk factors have been studied intensively in recent years and it has become apparent that risk is associated with genetic, environmental and clinical factors. The most strongly associated environmental and clinical factors are increasing age, cigarette smoking and previous cataract surgery, whilst moderate associations include high body mass index, history of cardiovascular disease, hypertension and high plasma fibrinogen (Chakravarthy et al., 2010). Dietary factors have been associated with increased AMD risk include a high fat intake (Seddon, 2013). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Age-related macular degeneration (AMD) is a leading cause of visual impairment. It is characterised by damage to a tissue complex composed of the retinal pigment epithelium, Bruch's membrane and choriocapillaris. In early AMD extracellular debris including drusen accumulates in Bruch's membrane and then in late AMD geographic atrophy and/or neovascularisation develop. Variants in genes encoding components of the alternative pathway of the complement cascade have a major influence on AMD risk, especially at the RCA locus on chromosome 1, which contains CFH and the CFHR genes. Immunohistochemical studies have demonstrated complement components in unaffected and AMD macular tissue. Whilst other factors, including oxidative stress, play important roles in AMD pathogenesis, evidence for the central role played by complement dysregulation is discussed in this review. Copyright © 2015. Published by Elsevier Ltd.
    Molecular Immunology 03/2015; 67(1). DOI:10.1016/j.molimm.2015.02.032 · 2.97 Impact Factor
  • Source
    • "Moreover, previous studies have demonstrated strong correlations between AMD and multiple environmental factors. In addition to age, many risk factors are correlated with AMD, such as cigarette smoking [5], oxidative stress [6] [7] [8], hypertension, previous cataract surgery, higher body mass index, a history of cardiovascular disease, and higher plasma fibrinogen [9]. AMD is characterized by complex traits. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Identifying disease genes is one of the most important topics in biomedicine and may facilitate studies on the mechanisms underlying disease. Age-related macular degeneration (AMD) is a serious eye disease; it typically affects older adults and results in a loss of vision due to retina damage. In this study, we attempt to develop an effective method for distinguishing AMD-related genes. Gene ontology and KEGG enrichment analyses of known AMD-related genes were performed, and a classification system was established. In detail, each gene was encoded into a vector by extracting enrichment scores of the gene set, including it and its direct neighbors in STRING, and gene ontology terms or KEGG pathways. Then certain feature-selection methods, including minimum redundancy maximum relevance and incremental feature selection, were adopted to extract key features for the classification system. As a result, 720 GO terms and 11 KEGG pathways were deemed the most important factors for predicting AMD-related genes.
    BioMed Research International 08/2014; 2014:450386. DOI:10.1155/2014/450386 · 1.58 Impact Factor
  • Source
    • "Both environment and genetic factors contribute equally to the progression of AMD pathology. Several studies have defined the role of modifiable environment factors like smoking, BMI, omega-3, carotenoids, trans-unsaturated fat intake etc [1] [2] [3] [4] [5] which could modulate the combined effect of several genetic susceptibility factors functional in multiplicative or in additive manner [6-8]. The fundamental basis of modulation of these genetic factors may be explained by epigenetic changes in genes or on the regulatory sequences of these genes. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Age related macular degeneration (AMD) is one of the major retinal degenerative disease of ageing whose complex genetic basis remains undeciphered. The involvement of various other factors like mitochondrial genes, cytoskeletal proteins and the role of epigenetics has been described in this review. Several population based AMD genetic studies have been carried out worldwide. Despite the increased publication of reports, clinical translation still eludes this davastating disease. We suggest models to address roadblocks in clinical translation hoping that these would be beneficial to drive AMD research towards innovative biomarkers and therapeutics Therefore, addressing the need large autopsy studies and combining it with efficient use of bioinformatic tools, statistical modeling and probing SNP-biomarker association are key to time bound resolution of this disease.
    Current Genomics 08/2014; 15(4). DOI:10.2174/1389202915666140516204512 · 2.34 Impact Factor
Show more