HbA(1c), fasting and 2 h plasma glucose in current, ex- and never-smokers: a meta-analysis

Soraya Soulimane, Dominique Simon, William H. Herman, Celine Lange, Crystal M. Y. Lee, Stephen Colagiuri, Jonathan E. Shaw, Paul Z. Zimmet, Dianna Magliano, Sandra R. G. Ferreira, Yanghu Dong, Lei Zhang, Torben Jorgensen, Jaakko Tuomilehto, Viswanathan Mohan, Dirk L. Christensen, Lydia Kaduka, Jacqueline M. Dekker, Giel Nijpels, Coen D. A. StehouwerOlivier Lantieri, Wilfred Y. Fujimoto, Donna L. Leonetti, Marguerite J. McNeely, Knut Borch-Johnsen, Edward J. Boyko, Dorte Vistisen, Beverley Balkau*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review


Aims/Hypothesis The relationships between smoking and glycaemic variables have not been well explored. We compared HbA(1c), fasting plasma glucose (FPG) and 2 h plasma glucose (2H-PG) in current, ex-and never-smokers. Methods This meta-analysis used individual data from 16,886 men and 18,539 women without known diabetes in 12 DETECT-2 consortium studies and in the French Data from an Epidemiological Study on the Insulin Resistance Syndrome (DESIR) and Telecom studies. Means of three glycaemic variables in current, ex-and never-smokers were modelled by linear regression, with study as a random factor. The I 2 statistic was used to evaluate heterogeneity among studies. Results HbA(1c) was 0.10% (95% CI 0.08, 0.12) (1.1 mmol/mol [0.9, 1.3]) higher in current smokers and 0.03% (0.01, 0.05) (0.3 mmol/mol [0.1, 0.5]) higher in ex-smokers, compared with never-smokers. For FPG, there was no significant difference between current and never-smokers (-0.004 mmol/l [-0.03, 0.02]) but FPG was higher in ex-smokers (0.12 mmol/l [ 0.09, 0.14]). In comparison with never-smokers, 2H-PG was lower (-0.44 mmol/l [-0.52, -0.37]) in current smokers, with no difference for ex-smokers (0.02 mmol/l [-0.06, 0.09]). There was a large and unexplained heterogeneity among studies, with I-2 always above 50%; I-2 was little changed after stratification by sex and adjustment for age and BMI. In this study population, current smokers had a prevalence of diabetes that was 1.30% higher as screened by HbA(1c) and 0.52% lower as screened by 2H-PG, in comparison with never-smokers. Conclusion/interpretation Across this heterogeneous group of studies, current smokers had a higher HbA1c and lower 2H-PG than never-smokers. This will affect the chances of smokers being diagnosed with diabetes.
Original languageEnglish
Pages (from-to)30-39
Issue number1
Publication statusPublished - Jan 2014


  • FPG
  • HbA(1c)
  • 2H-PG
  • Meta-analysis
  • Smoking

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