An evaluation of the guidelines of the Society of Obstetricians and Gynaecologists of Canada.

Clinical practice guidelines hope to offer unbiased, evidence-based guidance for clinicians. This paper examines levels of evidence contained within the guidelines of the Society of Obstetricians and Gynaecologists of Canada and compares classification of the recommendation (CoR) A/B/C/D/E/L (derived from evidence and consensus) versus quality of evidence assessment (QoEA) I-III. 1250 recommendations were analysed and 43% of recommendations were graded as "good" evidence, the highest grade of CoR, while just 24.6% of recommendations were based on the highest level of QoEA (level I). The paper discusses possible reasons for this discrepancy. The authors hope that this analysis promotes greater transparency in evidence-based medicine ultimately leading to using the best quality of evidence available yet taking into account any areas of scientific uncertainty. This will enhance respectful care of patients, while taking into account their autonomy and furthering the cause of patient centre care.

Chronic metformin associated cardioprotection against infarction: not just a glucose lowering phenomenon.

PURPOSE: Clinical and experimental investigations demonstrated that metformin, a widely used anti-diabetic drug, exhibits cardioprotective properties against myocardial infarction. Interestingly, metformin was previously shown to increase the expression of PGC-1α a key controller of energy metabolism in skeletal muscle, which is down-regulated in diabetic conditions. We hypothesized that chronic treatment with metformin could protect the aged, diabetic heart against ischemia-reperfusion injury (IRI) by up-regulating PGC-1α and improving the impaired functionality of diabetic mitochondria. METHODS: Following 4 weeks of metformin (300 mg/kg) administered in the drinking water, 12 month-old diabetic Goto Kakizaki and non-diabetic Wistar rat hearts were assigned for infarct measurement following 35 min ischemia and 60 min reperfusion or for electron microscopy (EM) and Western blotting (WB) investigations. RESULTS: Metformin elicited a cardioprotective effect in both non-diabetic and diabetic hearts. In contrast with the diabetic non-treated hearts, the diabetic hearts treated with metformin showed more organized and elongated mitochondria and demonstrated a significant increase in phosphorylated AMPK and in PGC-1α expression. CONCLUSIONS: In summary these results show for the first time that chronic metformin treatment augments myocardial resistance to ischemia-reperfusion injury, by an alternative mechanism in addition to the lowering of blood glucose. This consisted of a positive effect on mitochondrial structure possibly via a pathway involving AMPK activation and PGC-1α. Thus, metformin prescribed chronically to patients may lead to a basal state of cardioprotection thereby potentially limiting the occurrence of myocardial damage by cardiovascular events.