Effect of piracetam on the cognitive performance of patients undergoing coronary bypass surgery: A meta-analysis.

Cognitive impairments are observed in numerous patients following coronary bypass surgery, and piracetam are nootropic compounds that modulate cerebral functions by directly enhancing cognitive processes. The present meta-analysis was conducted to evaluate the protective effect of piracetam on the cognitive performance of patients undergoing coronary bypass surgery. The relevant studies were identified by searching Medline, EMBASE, PubMed and the Cochrane Library up to June 2013 and the pertinent bibliographies from the retrieved studies were reviewed. Data were selected from the studies according to predefined criteria. The meta-analysis included two randomized control trials involving 184 patients and including the Syndrom-Kurz test (SKT). Findings of the meta-analysis showed that following treatment the change from baseline observed in five SKT subtest scores, conducted with piracetam patients, indicated a significant advantage over those patients that were in the placebo group. The subtests included immediate pictured object recall, weighted mean difference (WMD)=0.91, 95% confidence interval (CI) 0.51-1.31, P<0.00001; delayed pictured object recall, WMD=0.74, 95% CI 0.19-1.28, P=0.008; delayed picture recognition, WMD=0.82, 95% CI 0.31-1.31, P=0.001; immediate word recall, WMD=0.87, 95% CI 0.47-1.28, P<0.0001; and letter interference, WMD=3.46, 95% CI -5.69 to -1.23, P=0.002. These results indicated that piracetam may have been effective in improving the short-term cognitive performance of patients undergoing coronary bypass surgery. High quality, well-controlled and longer randomized trials are required to corroborate this result.