***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Contrast-induced nephropathy limits the outcomes of percutaneous coronary intervention ( PCI ) . The present study compared the protective effects of different statin doses on renal function . A total of 228 patients with acute coronary syndrome undergoing selective PCI were r and omly divided into simvastatin 20-mg group ( S20 , n = 115 ) and simvastatin 80-mg group ( S80 , n = 113 ) . Serum creatinine was measured at admission , the day of PCI , and 24 and 48 hours after PCI . The creatinine clearance was calculated using the Cochcroft-Gault formula . High-sensitive C-reactive protein , P-selectin , and intercellular adhesion molecule-1 were also measured before and after the procedure . Contrast-induced nephropathy was defined as a postprocedure increase in serum creatinine of > or = 0.5 mg/dl or > 25 % from baseline . The serum creatinine significantly increased after PCI , with the peak value occurring at 24 hours , and then began to decrease . At 48 hours , the serum creatinine had decreased to the baseline level in the S80 group , but it had failed to do so in the S20 group . At 24 and 48 hours after PCI , the serum creatinine was lower in the S80 group than in the S20 group ( p < 0.05 and p < 0.001 , respectively ) . The creatinine clearance significantly decreased after PCI , with the lowest value occurring at 24 hours , and then it began to increase . In the S80 group , the creatinine clearance recovered to baseline level at 48 hours , but it failed to do so in the S20 group . The creatinine clearance was greater at 24 and 48 hours in the S80 group than that in the S20 group . Although the procedure caused a significant increase in high-sensitive C-reactive protein , P-selectin , and intercellular adhesion molecule-1 levels , the value was lower in the S80 group than in the S20 group ( p < 0.001 ) . In conclusion , pretreatment with simvastatin 80 mg before PCI could further decrease the occurrence of contrast-induced nephropathy compared with simvastatin 20 mg . This benefit was associated with the lowering of high-sensitive C-reactive protein , P-selectin , and intercellular adhesion molecule-1 levels We investigated the efficacy of short-term high-dose atorvastatin in decreasing the risk of contrast-induced nephropathy ( CIN ) in patients with chronic kidney disease ( CKD ) subjected to coronary angiography and /or angioplasty . CIN occurs in up to 15 % of patients with pre-existing CKD and affects clinical outcome . The protective effect of statin therapy against CIN is still controversial . A prospect i ve , single-center study of 304 patients with baseline estimated creatinine clearance < 60 ml/min were r and omized to receive atorvastatin 80 mg/day or placebo for 48 hours before and 48 hours after contrast medium administration . All patients received intravenous saline hydration and oral N-acetylcysteine 1,200 mg 2 times/day . Iso-osmolar contrast medium was used . CIN was defined as an absolute increase of serum creatinine > or = 0.5 mg/dl within 5 days after the procedure . CIN occurred in 31 patients ( 10 % ) , 16 ( 11 % ) in the placebo group and 15 ( 10 % ) in the atorvastatin group ( p = 0.86 ) . Mean increase in creatinine was not significantly different in the 2 groups ( 0.59 + or - 0.17 in placebo group vs 0.72 + or - 0.26 mg/dl in atorvastatin group , p = 0.31 ) . Persistent kidney injury , defined as 1-month increase from baseline creatinine value > or = 25 % , was observed in 30 % in the placebo group and in 31 % in the atorvastatin group ( p = 0.58 ) . In conclusion , a short-term administration of high doses of atorvastatin before and after contrast exposure , in addition to st and ard intravenous hydration and oral N-acetylcysteine , does not decrease CIN occurrence in patients with pre-existing CKD Objectives : To investigate whether preprocedural high-dose atorvastatin decreases the incidence of contrast-induced nephropathy ( CIN ) and protects the renal function after emergency percutaneous coronary intervention ( PCI ) . Methods : Statin-naive patients with acute ST-segment elevation myocardial infa rct ion ( STEMI ) undergoing emergency PCI ( n = 161 ) r and omly received atorvastatin ( 80 mg , n = 78 , ATOR group ) or placebo [ n = 83 , control ( CON ) group ] followed by long-term atorvastatin ( 40 mg/day ) . The primary end point was incidence of CIN . Results : In the ATOR group , 2.6 % of the patients developed CIN versus 15.7 % in the CON group ( p = 0.01 ) . In the ATOR group , postprocedural serum creatinine was significantly lower ( 93.4 ± 17.1 vs. 112.6 ± 23.3 µmol/l at 48 h and 84.2 ± 14.2 vs. 95.3 ± 17.7 µmol/l at 72 h , both p < 0.0001 ) and in the CON group , peak serum cystatin C was lower ( 0.51 ± 0.14 vs. 0.61 ± 0.13 mg/l , p < 0.0001 ) . Atorvastatin pretreatment was independently associated with a decreased risk of CIN ( OR 0.084 , 95 % CI 0.015–0.462 , p = 0.004 ) . The proportion of alanine aminotransferase > 3 × upper limit of the normal value within 1 month was 3.85 versus 1.20 % ( ATOR vs. CON group , p = 0.57 ) . Conclusion : Preprocedural high-dose atorvastatin prevents CIN and protects the renal function in patients with acute STEMI undergoing emergency PCI OBJECTIVE To compare the efficacy of high and low dose atorvastatin on preventing  contrast induced nephropathy ( CIN ) in patients underwent diagnostic and therapeutic coronary intervention . METHODS All patients received atorvastatin 10 mg/d on the basis of hydrated therapy ( n = 100 ) and high dose group received additional atorvastatin 80 mg at 12 to 24 hours before procedure ( n = 50 ) . Scr , Ccr , blood beta(2)-M , urine NAG/Cr , and urine osmolality before and after the procedure were compared between the groups . RESULTS Baseline demographic characteristics and nephropathy risk factors were similar between groups . Ccr was significantly reduced while blood beta(2)-M and uric NAG/Cr were significantly increased in low dose group ( all P < 0.05 ) . Blood beta(2)-M in the high dose group was significantly lower than that in the low dose group at day 1 [ ( 2.35 + /- 0.52 ) mg/L vs. ( 2.67 + /- 0.64 ) mg/L , P = 0.008 ] , day 3 [ ( 2.49 + /- 0.55 ) mg/L vs. ( 2.80 + /- 0.64 ) mg/L , P = 0.011 ] and day 5 [ ( 2.29 + /- 0.53 ) mg/L vs. ( 2.56 + /- 0.66 ) mg/L , P = 0.026 ] post-procedure respectively;urine NAG/Cr in the high dose group was also significantly lower than that in the low dose group at day 1 [ ( 1.19 + /- 0.30 ) U/mmol vs. ( 1.46 + /- 0.34 ) U/mmol , P < 0.001 ] , day 3 [ ( 1.30 + /- 0.30 ) U/mmol vs. ( 1.59 + /- 0.33 ) U/mmol , P < 0.001 ] , and day 5 [ ( 1.10 + /- 0.30 ) U/mmol vs. ( 1.34 + /- 0.35 ) U/mmol , P = 0.001 ] post-procedure respectively;Ccr in the high dose group was significantly higher than that in the low dose group at day 1 [ ( 73.69 + /- 20.99 ) ml/min vs. ( 65.19 + /- 18.72 ) ml/min , P = 0.035 ] , day 3 [ ( 64.04 + /- 15.82 ) ml/min vs. ( 56.79 + /- 14.50 ) ml/min , P = 0.019]post-procedure respectively . CONCLUSION High dose atorvastatin use before angiography is superior than low dose atorvastatin on attenuating contrast induced renal dysfunction Background — The role of statins in the prevention of contrast-induced acute kidney injury ( CIAKI )  is controversial . Methods and Results — First , we investigated the in vivo effects of atorvastatin on CIAKI .  Patients with chronic kidney disease enrolled in the Novel Approaches for Preventing or Limiting Events ( NAPLES ) II trial were r and omly assigned to ( 1 ) the  atorvastatin group ( 80 mg within 24 hours before contrast media [ CM ] exposure ; n=202 ) or ( 2 ) the control group ( n=208 ) . All patients received a high dose of N-acetylcysteine and sodium bicarbonate solution . Second , we investigated the in vitro effects of atorvastatin pretreatment on CM-mediated modifications of intracellular pathways leading to apoptosis or survival in renal tubular cells . CIAKI ( ie , an increase > 10 % of serum cystatin C concentration within 24 hours after CM exposure ) occurred in 9 of 202 patients in the atorvastatin group ( 4.5 % ) and in 37 of 208 patients in the control group ( 17.8 % ) ( P=0.005 ; odds ratio=0.22 ; 95 % confidence interval , 0.07–0.69 ) . CIAKI rate was lower in the  atorvastatin group in both diabetics and nondiabetics and in patients with moderate chronic kidney disease ( estimated glomerular filtration rate , 31–60 mL/min per 1.73 m2 ) . In the in vitro model , pretreatment with atorvastatin ( 1 ) prevented CM-induced renal cell apoptosis by reducing stress kinases activation and ( 2 ) restored the survival signals ( mediated by Akt and ERK pathways ) . Conclusions — A single high loading dose of atorvastatin administered within 24 hours before CM exposure is effective in reducing the rate of CIAKI . This beneficial effect is observed only in patients at low to medium risk A decline in kidney function after contrast exposure is associated with a high risk of morbidity and mortality during hospitalization and over long-term periods . Several retrospective and recent prospect i ve clinical trials have shown that statin therapy might prevent contrast-induced nephropathy in patients undergoing percutaneous coronary intervention . In this study , we aim ed to assess the effects of statin therapies on renal function parameters in patients undergoing elective coronary angiography . One hundred and sixty patients undergoing elective coronary angiography were r and omized equally into two groups : atorvastatin 40 mg/day group ( statin started 3 days before coronary angiography ) and an untreated control group . An additional 80 patients were included as a chronic statin therapy group . Serum creatinine , serum cystatin C , and glomerular filtration rate ( GFR ) were measured before and 48 h after coronary angiography . Cockcroft – Gault and Modification of Diet in Renal Disease ( MDRD ) equations were used to determine GFR . After coronary angiography , serum creatinine and GFR determined by MDRD were significantly better in patients using atorvastatin than those in controls ( P = 0.002 and P = 0.004 , respectively ) . Postprocedure serum creatinine , cystatin C , and GFR determined by MDRD were also significantly better in chronic statin therapy group than those in controls ( P = 0.006 , P = 0.003 , and P = 0.004 , respectively ) . There were no differences in renal function parameters between the short-term atorvastatin group and the chronic statin therapy group . Our data demonstrate that the use of short-term atorvastatin and chronic statin therapy may have a role in protecting renal function after elective coronary angiography OBJECTIVE To evaluate the efficacy of atorvastatin in preventing contrast agent-induced nephrop 
    Output:
    
A greater risk reduction in CI-AKI in the statin group significantly correlated with higher estimated glomerular filtration rate ( eGFR ; p=0.003 ) CONCLUSIONS : The present trial sequential analysis provides support for statins in reducing the incidence of  CI-AKI in patients undergoing CAG/PCI .
This effect appeared to be greater in patients with higher eGFR