2021 年 85 巻 2 号 p. 130-138
Serum uric acid (UA) is taken up by endothelial cells and reduces the level of nitric oxide (NO) by inhibiting its production and accelerating its degradation. Cytosolic and plasma xanthine oxidase (XO) generates superoxide and also decreases the NO level. Thus, hyperuricemia is associated with impaired endothelial function. Hyperuricemia is often associated with vascular diseases such as chronic kidney disease (CKD) and cardiovascular disease (CVD). It has long been debated whether hyperuricemia is causally related to the development of these diseases. The 2020 American College of Rheumatology Guideline for the Management of Gout (ACR2020) does not recommend pharmacological treatment of hyperuricemia in patients with CKD/CVD. In contrast, the Japanese Guideline on Management of Hyperuricemia and Gout (JGMHG), 3rdedition, recommends pharmacological treatment of hyperuricemia in patients with CKD. In a FREED study on Japanese hyperuricemic patients with CVD, an XO inhibitor, febuxostat, improved the primary composite endpoint of cerebro-cardio-renovascular events, providing a rationale for the use of urate-lowering agents (ULAs). Since a CARES study on American gout patients with CVD treated with febuxostat revealed increased mortality, ACR2020 recommends switching to different ULAs. However, there was no difference in the mortality of Japanese patients between the febuxostat-treated group and the placebo or allopurinol-treated groups in either the FEATHER or FREED studies.