Background Patients with rheumatoid arthritis have a higher energy expenditure than healthy controls. Released cytokines have thermogenic effect, which initially increases the metabolic rate.
Insulin resistance is also increased in inflammatory conditions like RA.
Objectives To investigate relationship between serum lactate and 3-hydroxybutyrate and patient reported outcomes: general health (GH,VAS) and pain (VAS), among patients with newly diagnosed rheumatoid arthritis (RA) in a population based cohort.
Methods For quantification of lactate and 3-hydroxybutyrate serum nuclear magnetic resonance platform operating at 500 MHz was used in native serum samples from patients with RA participating in Northern Savo 2010 Study. Age-and BMI-adjusted correlation between lactate and 3-hydroxybutyrate with GH and pain were counted. The 95% confidence intervals for the correlations were obtained by bias-corrected bootstrapping (5,000 replications).
Results Serum samples from 63 patients, 34 females and 29 males with RA satisfying the ACR/Eular 2010 classification criteria were studied. The mean age (SD) of patients was 59.1 (12.0) years and the BMI 27.3 (5.4) kg/m2. 69.8% had anti-CCP antibodies. The mean DAS28 was 4.4 (1.3), GH 52.7 (25.7), pain 56.4 (29.1), HAQ 0.70 (0.65), and GP 1.62 (0.29) mmol/L. The concentrations of lactate and 3-hydroxybutyrate were 1.46±0.27 mmol/L and 0.178±0.12 mmol/l, respectively.
Age- and BMI-adjusted correlations for the concentrations of lactate and 3-hydroxybutyrate with GH and pain are shown in table.
There were either no correlation between the concentration of lactate and CRP, or 3-hydroxybutyrate and CRP.
Conclusions In untreated RA GH correlated positively with 3-hydroxybutyrate reflecting adverse influence of fatty acid metabolism induced ketogenesis on patients' well-being. The finding also displays insulin resistance associated with RA.
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Disclosure of Interest None declared