Comparison of Serum Uric Acid in Major Depressive Disorder and Bipolar Disorder: a Retrospective Chart Review Study

Abstract

Background: Uric acid (UA) has been suggested as a possible biomarker of bipolar disorder (BD) in recent studies. We aimed to provide a clearer comparison of UA levels between BD and major depressive disorder (MDD). Methods: We retrospectively reviewed the medical chart records of psychiatric inpatients aged 19-60 years, whose main discharge diagnoses were either MDD or BD, with an admission between January 1, 2015 and December 31, 2018 at Seoul National University Hospital. Data such as sex, age, body mass index (BMI), medication usage, and serum UA levels were extracted. Patients with medical conditions or on medications that could influence UA levels were excluded. Age, sex, BMI, and psychiatric drug usage were considered in the comparison of serum UA between MDD and BD patients. Results: Our sample consisted of 142 MDD patients and 234 BD patients. The BD patients had significantly higher serum UA levels compared to the MDD patients, without accounting for other confounding variables (5.75 ± 1.56 mg/dL vs. 5.29 ± 1.59 mg/dL, P = 0.006). T-test comparisons between psychiatric medication users and non-users revealed that mood stabilizers and antipsychotics may be relevant confounding factors in our sample analysis. The likelihood of BD diagnosis was significantly correlated with higher UA levels (odds ratio, 1.410; 95% confidence interval, 1.150-1.728; P = 0.001) when accounting for sex, age, and BMI in the logistic regression analysis. Also, accounting for mood stabilizers or antipsychotics, the likelihood of BD diagnosis was still significantly correlated with higher UA levels. Conclusion: Our study confirms that BD patients are significantly more likely to show higher serum UA levels than MDD patients. The high UA levels in BD point to purinergic dysfunction as an underlying mechanism that distinguishes BD from MDD. Further research is recommended to determine whether UA is a trait or a state marker and whether UA correlates with the symptoms and severity of BD.

The Serum Uric Acid Level of Bipolar Depression: A Retrospective Real-World Study

“…The results of this study are basically consistent with previous studies. A case-control cross-sectional study by Albert compared the uric acid levels in different stages of BD (mania, euthymia and bipolar depression) found no difference, but compared with the age and gender matched control group, it was found that the uric acid levels in BD group were higher than those in Major Depressive Disorder (MDD), Obsessive-Compulsive Disorder (OCD), and Schizophrenia [27].A retrospective study found that uric acid levels with mood stabilizers and antipsychotics were higher than those without these drugs, and there was no difference in uric acid levels with or without antidepressants [28].Another cross-sectional retrospective real-world study found that uric acid levels in the BD group were higher than those in the MDD group in adolescents aged 10-18 [29].A 10-year follow-up found that MDD patients with higher uric acid levels had a higher risk of subsequent manic episodes [30].The results of a meta-analysis showed that uric acid levels in BD patients with manic episodes were higher than those in BD patients with depressive episodes [31].…”

Uric acid levels in adult patients with severe eating disorders

“…Hyperuricemia has been proposed to potentially have behavioral effects, including foraging and impulsive behaviors (Johnson et al, 2021;Succurro et al, 2015;Sutin et al, 2014), as well as mood and anxiety disorders (Bartoli et al, 2018;Black, Bot, Scheffer, Snieder, & Penninx, 2018). Differences in serum UA levels amongst women with MDD have also been associated with suicide risk (Kim, Rhee, Song, & Ahn, 2020). Regarding bipolar disorder, it has been postulated that higher serum UA levels may be present, with potentially Abbreviations: AN-BP-anorexia nervosa, binge-purge subtype; AN-R, anorexia nervosa, restricting subtype; ARFID, avoidant restrictive food intake disorder.…”

The Purinergic System as a Target for the Development of Treatments for Bipolar Disorder

“…Of note, patients with MDD have shown the lowest levels of UA when compared to patients with BD or healthy subjects. These findings indicate an emerging role of UA as a biomarker for BD [ 102 ], potentially able to distinguish BD and MDD [ 103 – 106 ]. However, notwithstanding the current evidence, the UA-based discrimination between BD phases or between BD and MDD was only partially supported when further analyzed using a meta-analytical approach [ 107 ].…”