Association of inflammation with glycemic control, insulin sensitivity, and beta-cell function in diabetic cats

Background There is an association between inflammation and glycemic control (GC), β-cell function (BCF), and insulin resistance (IR) in humans. Hypothesis/Objectives To assess the association between acute phase reaction (APR) (indicating inflammation) and markers reflecting GC, BCF, IR, and the presence of comorbidities in diabetic cats. Animals Serial serum samples from 69 diabetic cats, treated with long-acting insulin or long-acting insulin in combination with long-acting exenatide at a single study center from 2013 to 2018. Methods In this retrospective study, acute phase proteins (APPs), serum amyloid A (SAA), α-1-acid glycoprotein (AGP), and haptoglobin (Hp) were measured. Quality of GC (based on fructosamine), BCF test results, IR measures, and the presence of comorbidities from 4 study visits (enrolment, months 1, 3, and 6) were included. Mixed effects modeling, principal component analysis, and χ2-test were used to assess associations. Results Glycemic control, BCF, and IR improved over the study period. There was no association between the quality of GC and the concentration of any of the 3 APPs (SAA: P = .35; AGP: P = .59; Hp: P = .1), nor an association between APR and fructosamine concentration (P = .35), BCF or IR measures (all P > .05). β-cell function was strongly associated with GC (P < .001; odds ratio 0.27; 95% CI, 0.14-0.51), but IR or APR were not. Acute phase reaction was not associated with comorbidities (P = .13). Conclusions and clinical importance Our data suggest that inflammatory state does not predict poor GC assessed by serum fructosamine concentration in diabetic cats, but BCF is an important determinant of GC.