Objective

Linked metabolic and cardiovascular comorbidities are prevalent in hyperuricemia and gout. For mechanistic insight into impact on inflammatory processes and cardiometabolic risk factors of xanthine oxidase inhibitor urate-lowering therapy (ULT) titration to target, we performed a prospective study of gout serum metabolomes from a ULT trial.

Methods

Sera of gout patients meeting the 2015 ACR/EULAR gout classification criteria (n = 20) and with hyperuricemia were studied at time zero and weeks 12 and 24 of febuxostat or allopurinol dose titration ULT. Ultrahigh performance liquid chromatography-tandem mass spectroscopy acquired the serum spectra. Data were assessed using the Metabolon and Metaboloanalyst software. Lipolysis validation assays were done in febuxostat and/or colchicine-treated 3T3-L1 differentiated adipocytes.

Results

Serum urate decreased from time zero (8.21 ±1.139 SD) at weeks 12 (5.965 ± 1.734 SD) and 24 (5.655 ±1.763 SD). Top metabolites generated by changes in nucleotide and certain amino acid metabolism and polyamine pathways were enriched at 12 and 24 weeks ULT, respectively. Decreases in multiple fatty acid metabolites were observed at 24 weeks, linked with obesity. In cultured adipocytes, febuxostat significantly decreased while colchicine increased the lipolytic response to β-adrenergic-agonism or TNF.

Conclusion

Metabolomic profiles linked xanthine oxidase inhibitor-based ULT titration to target with reduced serum free fatty acids. In vitro validation studies revealed that febuxostat, but not colchicine, reduced lipolysis in cultured adipocytes. Since soluble urate, xanthine oxidase inhibitor treatment, and free fatty acids modulate inflammation, our findings suggest that by suppressing lipolysis, ULT could regulate inflammation in gout and comorbid metabolic and cardiovascular disease.

To determine whether concurrent posttraumatic stress disorder (PTSD) should affect whether to augment or switch medications when major depressive disorder (MDD) has not responded to a prior antidepressant trial. Patients at 35 Veterans Health Administration medical centers from December 2012 to May 2015 with nonpsychotic MDD (N = 1,522) and a suboptimal response to adequate antidepressant treatment were randomly assigned to 3 "next step" treatments: switching to bupropion, augmenting the current antidepressant with bupropion, and augmenting with the antipsychotic aripiprazole. Blinded ratings with the 16-item Quick Inventory of Depressive Symptomatology-Clinician Rated (QIDS-C₁₆) determined remission and response by 12 weeks and relapse after remission. Survival analyses compared treatment effects in patients with concurrent PTSD diagnosed with the Mini-International Neuropsychiatric Interview (n = 717, 47.1%) and those without PTSD (n = 805, 52.9%). Patients diagnosed with PTSD showed more severe depressive symptoms at baseline and were less likely to achieve either remission or response by 12 weeks. Augmentation with aripiprazole was associated with greater likelihood of achieving response (68.4%) than switching to bupropion (57.7%) in patients with PTSD (relative risk [RR] = 1.26; 95% CI, 1.01-1.59) as well as in patients without PTSD (RR = 1.29; 95% CI, 1.05-1.97) (78.9% response with aripiprazole augmentation vs 66.9% with switching to bupropion). Treatment comparisons with the group receiving augmentation with bupropion were not significant. There was no significant interaction between treatment group and PTSD on remission (P = .70), response (P = .98), or relapse (P = .15). Although PTSD was associated with poorer overall outcomes, the presence of concurrent PTSD among Veterans in this trial did not affect the comparative effectiveness of medications on response, remission, or relapse after initial remission. ClinicalTrials.gov identifier: NCT01421342.