Fibrates may cause abnormal urinary betaine loss

Abnormal urinary loss of betaine is common in patients with the metabolic syndrome or diabetes mellitus. These patients are often treated with fibrates which alter renal function and raise plasma homocysteine concentrations.

- patients taking bezafibrate had higher betaine excretion than patients not taking fibrates
- of 32 patients taking bezafibrate, 20 had abnormal (>97.5 %-ile) betaine excretion
- plasma homocysteine correlated positively with betaine excretion in male patients with lipid disorders who were not taking fibrate, but the relationship was stronger if patients taking bezafibrate were included
- in elderly (>65 years) subjects with hypertension there was a similar correlation, which was stronger when a subject taking bezafibrate was included

Abnormal betaine excretion is common in patients treated with bezafibrate. Bezafibrate appears to exacerbate betaine loss, which will cause a rise in plasma homocysteine. Betaine supplementation could be considered in conjunction with fibrate therapy.

Lever et al (2009). "Fibrates may Cause an Abnormal Urinary Betaine Loss Which is Associated with Elevations in Plasma Homocysteine." Cardiovasc Drugs Ther. Epub Aug 4