Concentrations of the acute phase reactants high-sensitive C-reactive protein and YKL-40 and of interleukin-6 before and after treatment in patients with acromegaly and growth hormone deficiency

Background Acromegaly is accompanied by increased cardiovascular mortality and a cluster of proatherogenic risk factors. In the general population, ischaemic heart disease (IHD) is associated with elevated levels of inflammatory markers. The acute phase reactant (APR) C‐reactive protein (CRP) has been reported to be reduced in acromegaly and increase after treatment, suggesting that excess of GH/IGF‐I could have anti‐inflammatory effects. This is in accordance with results obtained in patients with growth hormone deficiency (GHD), where increased levels of CRP have been reported. Objective To investigate the hypothesis that the GH/IGF‐I system is a suppressive regulator of inflammatory processes. Subjects and methods Twenty‐one acromegalic patients and 19 GH‐deficient patients were studied. The two APRs CRP and YKL‐40 and the proinflammatory cytokine interleukin‐6 (IL‐6) were measured before and after treatment and in healthy matched controls. Results In acromegalic patients, serum concentrations of high‐sensitive CRP (hsCRP) and YKL‐40 were reduced compared to controls (P < 0·001) and increased (P < 0·001) after treatment, together with IL‐6 (P = 0·021), to levels comparable with controls. Pretreatment serum YKL‐40 and IL‐6 showed a significant inverse correlation with IGF‐I and GH. In GH‐deficient patients, hsCRP and YKL‐40 were elevated compared to controls (P = 0·001 and P = 0·048). During treatment, levels of both APRs showed a trend towards a decrease (P = 0·087 and P = 0·060), and after treatment, levels of YKL‐40 no longer differed from that of controls. Serum IL‐6 was not different from controls and did not change during GH treatment. Conclusion The results point to the possibility of a relationship between GH disturbances and inflammatory processes.