Glycated haemoglobin A1c as a risk factor of cardiovascular outcomes and all-cause mortality in diabetic and nondiabetic populations: a systematic review and meta-analysis

• Type: Another Publication in an International Scientific Journal
• Date: 2017

Authors

Cavero Redondo, I (Author) Other; peleteiro, b (Author) FMUP; Alvarez Bueno, C (Author) Other; Rodriguez Artalejo, F (Author) Other; Martinez Vizcaino, V (Author) Other

Journal

Title: BMJ Open

Vol. 7

ISSN: 2044-6055

Publisher: BMJ PUBLISHING GROUP

Indexing

ISI Web of Knowledge - 151 Citations

Scopus - 173 Citations

Other information

Authenticus ID: P-00N-5RD

DOI: 10.1136/bmjopen-2017-015949

Abstract (EN): Objective To examine the relationship between glycated haemoglobin A1c (HbA1c) levels and the risk of cardiovascular outcomes and all-cause mortality based on data from observational studies and to determine the optimal levels of HbA1c for preventing cardiovascular events and/or mortality in diabetic and non-diabetic populations. Review methods We systematically searched Medline, Embase, the Cochrane Central Register of Controlled Trials, the Cochrane Database of Systematic Reviews and Web of Science databases, from inception to July 2016, for observational studies addressing the association of HbA1c levels with mortality and cardiovascular outcomes. Random effects models were used to compute pooled estimates of HR and respective 95% CI for allcause mortality, cardiovascular mortality and risk of cardiovascular events, separately for people with and without diabetes. Results Seventy-four published studies were included in the systematic review, but only 46 studies could be incorporated in the meta-analysis. In both diabetic and nondiabetic populations, there was an increase in the risk of all-cause mortality when HbA1c levels were over 8.0% and 6.0%, respectively. The highest all-cause mortality in people with diabetes was HbA1c above 9.0% (HR= 1.69; 95% CI 1.09 to 2.66) and in those without diabetes was HbA1c above 6.0% (HR= 1.74; 95% CI 1.38 to 2.20). However, both diabetic and non-diabetic populations with lower HbA1c levels (below 6.0% HR= 1.57; 95% CI 1.14 to 2.17 and below 5.0% HR= 1.19; 95% CI 1.04 to 1.36, respectively) had higher all-cause mortality. Similar pooled estimates were found when cardiovascular mortality was the outcome variable. Conclusion HbA1c is a reliable risk factor of all-cause and cardiovascular mortality in both diabetics and non-diabetics. Our findings establish optimal HbA1c levels, for the lowest all-cause and cardiovascular mortality, ranging from 6.0% to 8.0% in people with diabetes and from 5.0% to 6.0% in those without diabetes.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 11