TY - JOUR
T1 - Dietary intake of oxalic acid affects plasma oxalic acid concentration in patients with kidney failure
AU - Visser, Wesley J.
AU - Hospers, Gideon Post
AU - van Egmond, Anneke M.E.
AU - Laging, Mirjam
AU - Verhoeven, Jeroen G.H.P.
AU - Baart, Sara J.
AU - Ramakers, Chris R.B.
AU - Mertens zur Borg, Ingrid R.A.M.
AU - Vos, Michel J.
AU - Kema, Ido P.
AU - Hesselink, Dennis A.
AU - van de Wetering, Jacqueline
AU - Reinders, Marlies E.J.
AU - Hoorn, Ewout J.
AU - Severs, David
AU - Roodnat, Joke I.
N1 - Publisher Copyright:
© 2025 The Author(s)
PY - 2025/6
Y1 - 2025/6
N2 - Background & aims: Hyperoxaluria may cause kidney stones, kidney function decline and eventually kidney (transplant) failure. High plasma concentrations may lead to systemic oxalosis. Plasma oxalic acid concentrations increase when kidney function deteriorates. Apart from kidney function, the contribution of dietary intake on the oxalic acid plasma concentration is unknown. Methods: Average and last 24 h dietary oxalic acid intake was assessed by a self-developed food frequency questionnaire. Based on frequency and portion size, the FFQ calculates daily average oxalic acid intake and last 24 h intake. Plasma oxalic acid concentration was determined immediately before kidney transplantation.Results: We included 418 patients, median age 62 years (51–69), 60 % male, 66 % on dialysis, median dialysis vintage 13 months (0–27). Average oxalic acid intake was 199 mg/day (range 4–1599); in the last 24 h before transplantation it was 138 mg/day (range 0–3906). Median plasma oxalic acid concentration was 32.2 μmol/L (range 4.6–243.2), while 98.3 % of patients had concentrations above the upper normal value (7.2 μmol/L). Multivariable linear regression analysis showed that plasma oxalic acid concentration was associated with average and last 24-h intake, body mass index, dialysis vintage, age, residual diuresis, and dialysis versus pre-dialysis status. The associations found are clinically relevant, with the lowest and highest intakes translating to plasma oxalic acid changes of 23.5 and 49.5 μmol/L, respectively. Conclusion: In nearly all patients with kidney failure plasma oxalic acid concentration was above the upper normal concentration and dietary oxalic acid intake affects plasma oxalic acid concentration.
AB - Background & aims: Hyperoxaluria may cause kidney stones, kidney function decline and eventually kidney (transplant) failure. High plasma concentrations may lead to systemic oxalosis. Plasma oxalic acid concentrations increase when kidney function deteriorates. Apart from kidney function, the contribution of dietary intake on the oxalic acid plasma concentration is unknown. Methods: Average and last 24 h dietary oxalic acid intake was assessed by a self-developed food frequency questionnaire. Based on frequency and portion size, the FFQ calculates daily average oxalic acid intake and last 24 h intake. Plasma oxalic acid concentration was determined immediately before kidney transplantation.Results: We included 418 patients, median age 62 years (51–69), 60 % male, 66 % on dialysis, median dialysis vintage 13 months (0–27). Average oxalic acid intake was 199 mg/day (range 4–1599); in the last 24 h before transplantation it was 138 mg/day (range 0–3906). Median plasma oxalic acid concentration was 32.2 μmol/L (range 4.6–243.2), while 98.3 % of patients had concentrations above the upper normal value (7.2 μmol/L). Multivariable linear regression analysis showed that plasma oxalic acid concentration was associated with average and last 24-h intake, body mass index, dialysis vintage, age, residual diuresis, and dialysis versus pre-dialysis status. The associations found are clinically relevant, with the lowest and highest intakes translating to plasma oxalic acid changes of 23.5 and 49.5 μmol/L, respectively. Conclusion: In nearly all patients with kidney failure plasma oxalic acid concentration was above the upper normal concentration and dietary oxalic acid intake affects plasma oxalic acid concentration.
UR - https://www.scopus.com/pages/publications/105000875907
U2 - 10.1016/j.clnesp.2025.03.030
DO - 10.1016/j.clnesp.2025.03.030
M3 - Article
C2 - 40127762
AN - SCOPUS:105000875907
SN - 2405-4577
VL - 67
SP - 303
EP - 310
JO - Clinical Nutrition ESPEN
JF - Clinical Nutrition ESPEN
ER -
