Fasting and post-prandial glucose and diabetic complication. A meta-analysis.
The reduction of hemoglobin A1c (HbA1c) levels is recognized as a useful means of preventing diabetic complications. HbA1c results from both fasting and post-prandial glycemia, and therefore FPG and PPG could provide different, and independent, contributions to long-term outcomes. Aim of the present meta-analysis is the assessment of the effects of reduction of FPG and PPG on cardiovascular outcomes in randomized controlled trials. An extensive search of Medline was performed for all randomized trials with a duration of at least 52 weeks and performed on glucose-lowering agents. Differences in the incidence of cardiovascular events, and all-cause and cardiovascular mortality were assessed in trials comparing different treatments with a between-group difference in FPG or PPG at endpoint greater than 1 mmol/l. The Mantel-Haenszel Odds Ratio (MH-OR) for cardiovascular events and all-cause and cardiovascular mortality in patients on more intensive treatments, in trials with a between-group difference of PPG greater than 1 mmol/l, was not significantly different from controls (MH-OR [95%CI] 0.90 [0.51-1.58] for MACE); on the contrary, more intensive treatment of FPG produced a significantly lower all-cause (MH-OR 0.90 [0.81-0.99], p = 0.03) and cardiovascular (MH-OR 0.86 [0.76-0.97], p = 0.012) mortality, with no significant effect on the incidence of major cardiovascular events. In conclusion, reduction of FPG is associated with reduced cardiovascular mortality. Data on PPG are still scarce, but they point in the same direction.