Short-term changes in inflammatory response protein (hsCRP) do not parallel with changes in coronary vasoreactivity...

Obese subjects are characterized by increased high-sensitivity C-reactive protein (hsCRP) and coronary vascular resistance. Clucocorticoids suppress inflammation, a possible cardioprotective effect. We tested the short-term anti-inflammatory effect of dexamethasone (dx) on these parameters in obese subjects.

Coronary vascular resistance was quantitated basally and during adenosine infusion with or without simultaneous euglycemic hyperinsulinemic clamp (insulin infusion rate of 1 mU/kg/min) in 11 obese and 19 age-matched nonobese males using positron emission tomography and (15)O-water. Each subject was studied both with and without previous dx treatment for 2 days (2 mg/day).

Before dx treatment, hsCRP concentration was significantly higher in obese than in nonobese subjects (1.55+/-1.73 vs 0.32+/-0.32 mg/l, P = 0.005). In addition, coronary vascular resistances were higher (P < 0.05) in obese than in nonobese subjects at baseline (139+/-36 vs 117+/-22) and during adenosine infusion without (32+/-7 vs 26+/-7) or with simultaneous clamp (26+/-8 vs 21+/-5 mmHg min g/ ml). Dx treatment decreased significantly hsCRP concentration in obese but not in nonobese subjects, leading to similar hsCRP concentrations between the groups (0.45+/-0.43 vs 0.26+/-0.42 mg/l, respectively, P = 0.3). Dx had no effect on coronary vascular resistances (NS).

Obese subjects are characterized by high hsCRP, which can be normalized by dx. However, despite this, coronary vascular resistances did not decrease in obese subjects. Short-term changes in inflammatory response protein appear not to parallel with changes in coronary vasoreactivity in obese men.