{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T18:44:24Z","timestamp":1776365064762,"version":"3.51.2"},"reference-count":83,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2020,7,30]],"date-time":"2020-07-30T00:00:00Z","timestamp":1596067200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100010801","name":"Xunta de Galicia","doi-asserted-by":"publisher","award":["ED431B 2019\/02"],"award-info":[{"award-number":["ED431B 2019\/02"]}],"id":[{"id":"10.13039\/501100010801","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003176","name":"Ministerio de Educaci\u00f3n, Cultura y Deporte","doi-asserted-by":"publisher","award":["BEAGAL18\/00142"],"award-info":[{"award-number":["BEAGAL18\/00142"]}],"id":[{"id":"10.13039\/501100003176","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003176","name":"Ministerio de Educaci\u00f3n, Cultura y Deporte","doi-asserted-by":"publisher","award":["PRX19\/00353"],"award-info":[{"award-number":["PRX19\/00353"]}],"id":[{"id":"10.13039\/501100003176","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Serum vitamin D deficiency is widespread among older adults and is a potential modifiable risk factor for frailty. Moreover, frailty has been suggested as an intermediate step in the association between low levels of vitamin D and mortality. Hence, we conducted a systematic review of the literature and meta-analysis to test the possible association of low concentrations of serum 25-hydroxyvitamin D (25(OH)D), a marker of vitamin D status, with frailty in later life. We reviewed cross-sectional or longitudinal studies evaluating populations of older adults and identifying frailty by a currently validated scale. Meta-analyses were restricted to cross-sectional data from studies using Fried\u2019s phenotype to identify frailty. Twenty-six studies were considered in the qualitative synthesis, and thirteen studies were included in the meta-analyses. Quantitative analyses showed significant differences in the comparisons of frail (standardized mean difference (SMD)\u20141.31, 95% confidence interval (CI) (\u22122.47, \u22120.15), p = 0.0271) and pre-frail (SMD\u20140.79, 95% CI (\u22121.58, \u22120.003), p = 0.0491) subjects vs. non-frail subjects. Sensitivity analyses reduced heterogeneity, resulting in a smaller but still highly significant between-groups difference. Results obtained indicate that lower 25(OH)D levels are significantly associated with increasing frailty severity. Future challenges include interventional studies testing the possible benefits of vitamin D supplementation in older adults to prevent\/palliate frailty and its associated outcomes.<\/jats:p>","DOI":"10.3390\/nu12082286","type":"journal-article","created":{"date-parts":[[2020,7,31]],"date-time":"2020-07-31T04:15:31Z","timestamp":1596168931000},"page":"2286","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":72,"title":["Low Vitamin D Levels and Frailty Status in Older Adults: A Systematic Review and Meta-Analysis"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7583-8041","authenticated-orcid":false,"given":"Diego","family":"Marcos-P\u00e9rez","sequence":"first","affiliation":[{"name":"Grupo DICOMOSA, Centro de Investigaciones Cient\u00edficas Avanzadas (CICA), Departamento de Psicolog\u00eda, Facultad de Ciencias de la Educaci\u00f3n, Campus Elvi\u00f1a s\/n, Universidade da Coru\u00f1a, 15071 A Coru\u00f1a, Spain"},{"name":"Instituto de Investigaci\u00f3n Biom\u00e9dica de A Coru\u00f1a (INIBIC), AE CICA-INIBIC, Oza, 15071 A Coru\u00f1a, Spain"}]},{"given":"Mar\u00eda","family":"S\u00e1nchez-Flores","sequence":"additional","affiliation":[{"name":"Grupo DICOMOSA, Centro de Investigaciones Cient\u00edficas Avanzadas (CICA), Departamento de Psicolog\u00eda, Facultad de Ciencias de la Educaci\u00f3n, Campus Elvi\u00f1a s\/n, Universidade da Coru\u00f1a, 15071 A Coru\u00f1a, Spain"},{"name":"Environmental Health Department, National Health Institute, Rua Alexandre Herculano 321, 4000-055 Porto, Portugal"},{"name":"EPIUnit\u2014Instituto de Sa\u00fade P\u00fablica, Universidade do Porto, Rua das Taipas, no 135, 4050-600 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9844-1482","authenticated-orcid":false,"given":"Stefania","family":"Proietti","sequence":"additional","affiliation":[{"name":"Scientific Direction, IRCCS San Raffaele Pisana, Via di Val Cannuta, 247, 00166 Rome, Italy"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3833-6717","authenticated-orcid":false,"given":"Stefano","family":"Bonassi","sequence":"additional","affiliation":[{"name":"Unit of Clinical and Molecular Epidemiology, IRCCS San Raffaele Pisana, Via di Val Cannuta, 247, 00166 Rome, Italy"},{"name":"Department of Human Sciences and Quality of Life Promotion, San Raffaele University, Via di Val Cannuta, 247, 00166 Rome, Italy"}]},{"given":"Solange","family":"Costa","sequence":"additional","affiliation":[{"name":"Environmental Health Department, National Health Institute, Rua Alexandre Herculano 321, 4000-055 Porto, Portugal"},{"name":"EPIUnit\u2014Instituto de Sa\u00fade P\u00fablica, Universidade do Porto, Rua das Taipas, no 135, 4050-600 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8693-5250","authenticated-orcid":false,"given":"Joao Paulo","family":"Teixeira","sequence":"additional","affiliation":[{"name":"Environmental Health Department, National Health Institute, Rua Alexandre Herculano 321, 4000-055 Porto, Portugal"},{"name":"EPIUnit\u2014Instituto de Sa\u00fade P\u00fablica, Universidade do Porto, Rua das Taipas, no 135, 4050-600 Porto, Portugal"}]},{"given":"Juan","family":"Fern\u00e1ndez-Tajes","sequence":"additional","affiliation":[{"name":"Wellcome Centre for Human Genetics, McCarthy\u2019s group, University of Oxford, Roosevelt Drive, Headington, Oxford OX3 7BN, UK"},{"name":"Genetic and Molecular Epidemiology Unit, Department of Clinical Sciences, CRC, SUS Malm\u00f6, Jan Waldenstr\u00f6ms gata 35, House 91:12, SE-214 28 Malm\u00f6, Sweden"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0650-8852","authenticated-orcid":false,"given":"Eduardo","family":"P\u00e1saro","sequence":"additional","affiliation":[{"name":"Grupo DICOMOSA, Centro de Investigaciones Cient\u00edficas Avanzadas (CICA), Departamento de Psicolog\u00eda, Facultad de Ciencias de la Educaci\u00f3n, Campus Elvi\u00f1a s\/n, Universidade da Coru\u00f1a, 15071 A Coru\u00f1a, Spain"},{"name":"Instituto de Investigaci\u00f3n Biom\u00e9dica de A Coru\u00f1a (INIBIC), AE CICA-INIBIC, Oza, 15071 A Coru\u00f1a, Spain"}]},{"given":"Vanessa","family":"Valdiglesias","sequence":"additional","affiliation":[{"name":"Instituto de Investigaci\u00f3n Biom\u00e9dica de A Coru\u00f1a (INIBIC), AE CICA-INIBIC, Oza, 15071 A Coru\u00f1a, Spain"},{"name":"EPIUnit\u2014Instituto de Sa\u00fade P\u00fablica, Universidade do Porto, Rua das Taipas, no 135, 4050-600 Porto, Portugal"},{"name":"Grupo DICOMOSA, Centro de Investigaciones Cient\u00edficas Avanzadas (CICA), Departamento de Biolog\u00eda, Facultad de Ciencias, Campus A Zapateira s\/n, Universidade da Coru\u00f1a, 15071 A Coru\u00f1a, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7649-2599","authenticated-orcid":false,"given":"Blanca","family":"Laffon","sequence":"additional","affiliation":[{"name":"Grupo DICOMOSA, Centro de Investigaciones Cient\u00edficas Avanzadas (CICA), Departamento de Psicolog\u00eda, Facultad de Ciencias de la Educaci\u00f3n, Campus Elvi\u00f1a s\/n, Universidade da Coru\u00f1a, 15071 A Coru\u00f1a, Spain"},{"name":"Instituto de Investigaci\u00f3n Biom\u00e9dica de A Coru\u00f1a (INIBIC), AE CICA-INIBIC, Oza, 15071 A Coru\u00f1a, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2020,7,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"720","DOI":"10.1016\/j.mayocp.2013.05.011","article-title":"Vitamin D for Health: A Global Perspective","volume":"88","author":"Holick","year":"2013","journal-title":"Mayo Clin. 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