AimTo observe the effects of hydration on renal function and the incidence of contrast-induced nephropathy in patients undergoing coronary angiography.MethodsThe low osmolar and nonionic contrast media (iohexol) was used in all patients.A total of 216 patients, who would undergo coronary angiograph or percutaneous coronary interventional theraphy were enrolled into the study.They were randomly divided into two groups: the hydration group(n=112) and the control group (n=104).The treated group received hydration theraphy as well as general intravenous fluid infusion.The control group only received general intravenous fluid infusion.The levels of serum creatinine (Scr) and urine β2-microglobulin (β2MG) were measured before angiography and 48 hours, one week after coronary angiograpy.The incidence of contrast-induced nephropathy (CIN) was observed in the two groups.ResultsThe levels of Scr and β2MG were both elevated in the two groups, especially in the control group.The levels began to decrease after one week.The incidence of CIN was 4% in hydration group, 17% in control group.ConclusionThe strengthened hydration therapy can reduce the renal damage and effectively prevent from contrast-induced nephropathy.