{"rowid": 17, "title": "[\"Vitamin D and its pathway genes in myopia: systematic review and meta-analysis\"]", "DOI": "10.1136/bjophthalmol-2018-312159", "URL": "http://dx.doi.org/10.1136/bjophthalmol-2018-312159", "created": "2018-07-17T16:26:52Z", "subject": "[\"Ophthalmology\", \"Sensory Systems\", \"Cellular and Molecular Neuroscience\"]", "references-count": "56", "is-referenced-by-count": "8", "ISSN": "[\"0007-1161\", \"1468-2079\"]", "container-title": "British Journal of Ophthalmology", "abstract": "<jats:sec><jats:title>Objective</jats:title><jats:p>To conduct a systematic review and meta-analysis of the association of blood vitamin D (25-hydroxyvitamin D, 25(OH)D) concentration and vitamin D pathway genes with myopia.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>We searched the MEDLINE and EMBASE databases for studies published up to 29 January 2018. Cross-sectional or cohort studies which evaluated the blood 25(OH)D concentration, blood 25(OH)D3 concentration or vitamin D pathway genes, in relation to risk of myopia or refractive errors were included. Standard mean difference (SMD) of blood 25(OH)D concentrations between the myopia and non-myopia groups was calculated. The associations of blood 25(OH)D concentrations and polymorphisms in vitamin D pathway genes with myopia using summary ORs were evaluated.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>We summarised seven studies involving 25 008 individuals in the meta-analysis. The myopia group had lower 25(OH)D concentration than the non-myopia group (SMD=\u22120.27 nmol/L, p=0.001). In the full analysis, the risk of myopia was inversely associated with blood 25(OH)D concentration after adjusting for sunlight exposure or time spent outdoors (adjusted odds ratio (AOR)=0.92 per 10 nmol/L, p&lt;0.0001). However, the association was not statistically significant for the &lt;18 years subgroup (AOR=0.91 per 10 nmol/L, p=0.13) and was significant only for 25(OH)D3 (likely to be mainly sunlight derived), but not total 25(OH)D (AOR=0.93 per 10 nmol/L, p=0.00007; AOR=0.91 per 10 nmol/L, p=0.15). We analysed four single nucleotide polymorphisms in the VDR gene from two studies; there was no significant association with myopia.</jats:p></jats:sec><jats:sec><jats:title>Conclusions</jats:title><jats:p>Lower 25(OH)D is associated with increased risk of myopia; the lack of a genetic association suggests that 25(OH)D level may be acting as a proxy for time outdoors.</jats:p></jats:sec>", "author_number": "9", "orcids": "[\"http://orcid.org/0000-0001-8352-6363\", \"http://orcid.org/0000-0003-0994-6196\", \"http://orcid.org/0000-0001-7914-4709\", \"http://orcid.org/0000-0003-2736-3541\", \"http://orcid.org/0000-0002-2156-1486\"]", "names": "[\"Shu Min Tang\", \"Tiffany Lau\", \"Shi Song Rong\", \"Seyhan Yazar\", \"Li Jia Chen\", \"David A Mackey\", \"Robyn M Lucas\", \"Chi Pui Pang\", \"Jason C Yam\"]", "award_numbers": "[\"14111515 (JCSY)\"]", "funder_names": "[\"General Research Fund (GRF), Research Grants Council, Hong Kong\", \"UBS Optimus Foundation Grant\", \"Direct Grants of the Chinese University of Hong Kong\"]", "funder_dois": "[[\"\"], [\"\"], [\"\"]]"}