{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,20]],"date-time":"2026-10-20T16:19:32Z","timestamp":1792513172602,"version":"4.5.0"},"reference-count":48,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"8","content-domain":{"domain":["lww.com","ovid.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2022,8]]},"abstract":"<jats:p>\n                    The aim of this systematic review and meta-analysis was to summarize and compare the available evidence on the level of vitamin D and antioxidant trace elements between the keratoconus (KC) patients and healthy controls. Seven case\u2013control studies with 830 subjects were found eligible with a systematic search using PubMed, SCOPUS, Web of Science, and EMBASE till November 21, 2021. Data were synthesized with a DerSimonian and Laird random-effects method of meta-analysis. The mean serum vitamin D level was significantly lower in the patients with KC [standardized mean difference (SMD): \u22120.71;\n                    <jats:italic toggle=\"yes\">P<\/jats:italic>\n                    &lt; 0.001] as compared with the control group. The mean serum vitamin D level decreased more in the progressive patients (SMD: \u22120.80;\n                    <jats:italic toggle=\"yes\">P<\/jats:italic>\n                    = 0.016) than in the stable patients (SMD: \u22120.66;\n                    <jats:italic toggle=\"yes\">P<\/jats:italic>\n                    &lt; 0.001) when compared with the control group. The mean serum zinc level was found significantly lower in the patients with KC compared with the control group (SMD: \u22121.98;\n                    <jats:italic toggle=\"yes\">P<\/jats:italic>\n                    = 0.005). Pooled analysis based on the two studies showed significantly lower mean selenium levels in the KC patients (SMD: \u22120.34;\n                    <jats:italic toggle=\"yes\">P<\/jats:italic>\n                    = 0.003). Regular evaluation of serum vitamin D, zinc, and selenium levels among the patients with KC at disease onset and future follow-ups could be promising in predicting the progressive disease and disease severity.\n                  <\/jats:p>","DOI":"10.4103\/ijo.ijo_3216_21","type":"journal-article","created":{"date-parts":[[2022,8,4]],"date-time":"2022-08-04T11:45:11Z","timestamp":1659613511000},"page":"2818-2824","update-policy":"https:\/\/doi.org\/10.1097\/lww.0000000000001000","source":"Crossref","is-referenced-by-count":15,"title":["Association of keratoconus with serum levels of 25-hydroxyvitamin D and antioxidant trace elements: A systematic review and meta-analysis"],"prefix":"10.4103","volume":"70","author":[{"given":"Parul C","family":"Gupta","sequence":"first","affiliation":[{"name":"Department of Ophthalmology, Postgraduate Institute of Medical Education and Research, Chandigarh, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mona","family":"Pathak","sequence":"additional","affiliation":[{"name":"Department of Population and Data Sciences, UT Southwestern Medical Center, Dallas, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bhaskar","family":"Thakur","sequence":"additional","affiliation":[{"name":"Department of Population and Data Sciences, UT Southwestern Medical Center, Dallas, USA"},{"name":"Department of Family and Community Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rajesh","family":"Fogla","sequence":"additional","affiliation":[{"name":"Cornea Clinic, Apollo Hospitals, Jubilee Hills, Hyderabad, Telangana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aniruddha","family":"Agarwal","sequence":"additional","affiliation":[{"name":"Eye Institute, Cleveland Clinic, Abu Dhabi, UAE"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jagat","family":"Ram","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Postgraduate Institute of Medical Education and Research, Chandigarh, India"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"276","published-online":{"date-parts":[[2022,7,29]]},"reference":[{"key":"B1-20240828","doi-asserted-by":"crossref","first-page":"157","DOI":"10.1016\/j.clae.2010.04.006","article-title":"Keratoconus:A review","volume":"33","author":"Romero-Jim\u00e9nez","year":"2010","journal-title":"Contact Lens Anterior Eye J Br Contact Lens Assoc"},{"key":"B2-20240828","first-page":"379","article-title":"Influence of ethnic origin on the incidence of keratoconus and associated atopic disease in Asians and white patients","volume":"18","author":"Georgiou","year":"2004","journal-title":"Eye Lond 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