{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,20]],"date-time":"2026-10-20T00:54:33Z","timestamp":1792457673519,"version":"4.5.0"},"reference-count":31,"publisher":"BMJ","issue":"5","license":[{"start":{"date-parts":[[2025,5,14]],"date-time":"2025-05-14T00:00:00Z","timestamp":1747180800000},"content-version":"unspecified","delay-in-days":13,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Open"],"accepted":{"date-parts":[[2025,5,1]]},"published-print":{"date-parts":[[2025,5]]},"abstract":"<jats:sec>\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>\n                      Vitamin B\n                      <jats:sub>12<\/jats:sub>\n                      deficiency is a common and neglected adverse effect experienced by type 2 diabetic patients treated with metformin. A lack of vitamin B\n                      <jats:sub>12<\/jats:sub>\n                      may have severe consequences, such as fatigue, macrocytic anaemia and worsened peripheral diabetic neuropathy. This study aims to identify the rate of vitamin B\n                      <jats:sub>12<\/jats:sub>\n                      deficiency and the associated factors in type 2 diabetic patients treated with metformin.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Design<\/jats:title>\n                    <jats:p>Cross-sectional study.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Setting and participants<\/jats:title>\n                    <jats:p>\n                      This study involved 145 type 2 diabetic patients treated with metformin in Cho Ray hospital, a tertiary healthcare centre in South Vietnam. The levels of vitamin B\n                      <jats:sub>12<\/jats:sub>\n                      and associated clinical and paraclinical parameters were measured and collected.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      The study population\u2019s mean age was 61.5 years, of which 51.7% were women. The median duration of metformin use was 10 years, and the median metformin dose was 1700\u2009mg. The vitamin B\n                      <jats:sub>12<\/jats:sub>\n                      deficiency rate was 22.1%. HbA1c, duration of metformin use and metformin dose were independent factors statistically associated with vitamin B\n                      <jats:sub>12<\/jats:sub>\n                      deficiency.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>\n                      This study identified the rate of vitamin B\n                      <jats:sub>12<\/jats:sub>\n                      deficiency and associated factors in type 2 diabetic patients treated with metformin. These findings can be helpful in screening patients and replacing vitamin B\n                      <jats:sub>12<\/jats:sub>\n                      in high-risk populations with vitamin B\n                      <jats:sub>12<\/jats:sub>\n                      deficiency.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Trial registration number<\/jats:title>\n                    <jats:p>Ethical Committee of Cho Ray Hospital (approval number 1711\/CN-H\u0110\u0110\u0110)<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bmjopen-2025-100672","type":"journal-article","created":{"date-parts":[[2025,5,15]],"date-time":"2025-05-15T02:05:19Z","timestamp":1747274719000},"page":"e100672","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":7,"title":["Association between vitamin B\n                    <sub>12<\/sub>\n                    deficiency and metformin use in type 2 diabetic patients: a cross-sectional study in a South Vietnam tertiary hospital"],"prefix":"10.1136","volume":"15","author":[{"given":"Hen Huu","family":"Phan","sequence":"first","affiliation":[{"name":"Department of Endocrinology, Cho Ray Hospital, Ho Chi Minh City, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"An Thuy Thi","family":"Nguyen","sequence":"additional","affiliation":[{"name":"Department of Endocrinology, Cho Ray Hospital, Ho Chi Minh City, Vietnam"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9997-6390","authenticated-orcid":false,"given":"Minh Duc","family":"Do","sequence":"additional","affiliation":[{"name":"Center for Molecular Biomedicine, University of Medicine and Pharmacy, Ho Chi Minh City, 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