Relationship Between Altered Plasma-Free Amino Acid Levels and Hyperuricemia in Dyslipidemia Without and With Hypertension

<b>Background:</b> Investigating the association between plasma-free amino acids (PFAAs) and hyperuricemia (HU) in dyslipidemia (DL) and dyslipidemia with hypertension (DH) is crucial, as it could provide valuable insights into the pathophysiology of these conditions and contribute to the development of targeted prevention and management strategies. Therefore, in this study, we aimed to elucidate the associations between PFAAs and HU in individuals with DL and DH. <b>Methods:</b> We quantified PFAAs and uric acid levels among Japanese healthy subjects (n = 1311; HU, n = 57), subjects with DL (n = 1483; HU, n = 219), and subjects with DH (n = 1159; HU, n = 237). <b>Results:</b> The concentrations of most PFAAs showed significant differences between subjects without and with HU across all groups (<i>p</i> < 0.05 to 0.001). Adjusted logistic regression analyses revealed that certain PFAAs were consistently positively or negatively associated with HU across all groups. Specifically, in the DL group, alanine, tryptophan, and tyrosine showed significant positive associations with HU, while in the DH group, citrulline and glutamate exhibited similar positive associations (<i>p</i> < 0.05 to 0.001). Conversely, threonine in the healthy group (<i>p</i> < 0.05) and glutamine in the DL group (<i>p</i> < 0.05) demonstrated significant inverse associations with HU. <b>Conclusions:</b> This study revealed a potential close relationship between alterations in PFAA profiles and HU in dyslipidemia, without and with hypertension. The findings warrant further research to elucidate the role of altered amino acid and uric acid levels as potential disease biomarkers and therapeutic targets.