TY - JOUR
T1 - Serum vitamin B12, distal symmetrical polyneuropathy and anaemia in type 2 diabetes
T2 - the Fremantle Diabetes Study Phase 2
AU - Davis, Timothy M. E.
AU - Chubb, Stephen A. P.
AU - Peters, Kirsten E.
AU - Davis, Wendy A.
PY - 2024/4
Y1 - 2024/4
N2 - Background: There are limited data relating to the effects of metformin-associated vitamin B12 deficiency on the risk of distal symmetrical polyneuropathy (DSPN) and megaloblastic anaemia in well-characterised community-based cohorts.Aims: To assess inter-relationships between metformin therapy, vitamin B12 defi- ciency assessed using serum active B12 concentrations, and DSPN and anaemia in 1492 Fremantle Diabetes Study Phase 2 (FDS2) participants with type 2 diabetes.Methods: Prevalence rates of vitamin B12 deficiency (total <80 pmol/L, active <23 pmol/L) and borderline deficiency (total z80 and s200 pmol/L, active z23 and s35 pmol/L) were determined using baseline sera. The relationship between vitamin B12 status and both DSPN and anaemia was assessed using multivariable analyses.Results: Most FDS2 participants (94.4%) were vitamin B12 replete (total serum con-centration >200 pmol/L, active >35 pmol/L), 2.0% were deficient (total <80 pmol/L, active <23 pmol/L) and the remainder (3.6%) borderline. Although metformin treat-ment increased the odds of deficiency (4.2%, 3.1% borderline) in a dose-dependent fashion (odds ratio (95% confidence interval) 39.4 (4.90-316) for >2000 mg daily com-pared with no treatment; P < 0.001), there was no significant association between vita-min B12 status and DSPN, anaemia (haemoglobin s130 g/L males, s120 g/L females), haemoglobin concentration or mean corpuscular volume (P z 0.147). Metformin increased the likelihood of anaemia, especially at high doses, independent of vitamin B12 deficiency.Conclusions: Since nutritional sources likely attenuate metformin-associated vitamin B12 malabsorption and its clinical sequelae in developed countries such as Australia, there is no need for routine/opportunistic serum vitamin B12 screening in metformin-treated patients.
AB - Background: There are limited data relating to the effects of metformin-associated vitamin B12 deficiency on the risk of distal symmetrical polyneuropathy (DSPN) and megaloblastic anaemia in well-characterised community-based cohorts.Aims: To assess inter-relationships between metformin therapy, vitamin B12 defi- ciency assessed using serum active B12 concentrations, and DSPN and anaemia in 1492 Fremantle Diabetes Study Phase 2 (FDS2) participants with type 2 diabetes.Methods: Prevalence rates of vitamin B12 deficiency (total <80 pmol/L, active <23 pmol/L) and borderline deficiency (total z80 and s200 pmol/L, active z23 and s35 pmol/L) were determined using baseline sera. The relationship between vitamin B12 status and both DSPN and anaemia was assessed using multivariable analyses.Results: Most FDS2 participants (94.4%) were vitamin B12 replete (total serum con-centration >200 pmol/L, active >35 pmol/L), 2.0% were deficient (total <80 pmol/L, active <23 pmol/L) and the remainder (3.6%) borderline. Although metformin treat-ment increased the odds of deficiency (4.2%, 3.1% borderline) in a dose-dependent fashion (odds ratio (95% confidence interval) 39.4 (4.90-316) for >2000 mg daily com-pared with no treatment; P < 0.001), there was no significant association between vita-min B12 status and DSPN, anaemia (haemoglobin s130 g/L males, s120 g/L females), haemoglobin concentration or mean corpuscular volume (P z 0.147). Metformin increased the likelihood of anaemia, especially at high doses, independent of vitamin B12 deficiency.Conclusions: Since nutritional sources likely attenuate metformin-associated vitamin B12 malabsorption and its clinical sequelae in developed countries such as Australia, there is no need for routine/opportunistic serum vitamin B12 screening in metformin-treated patients.
KW - Anaemia
KW - Distal symmetrical polyneuropathy
KW - Metformin
KW - Type 2 diabetes
KW - vitamin B12 deficiency
UR - https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=uwapure5-25&SrcAuth=WosAPI&KeyUT=WOS:001061273900001&DestLinkType=FullRecord&DestApp=WOS
U2 - 10.1111/imj.16225
DO - 10.1111/imj.16225
M3 - Article
C2 - 37665691
SN - 1444-0903
VL - 54
SP - 575
EP - 581
JO - Internal Medicine Journal
JF - Internal Medicine Journal
IS - 4
ER -