Elevated HbA1C linked to increased postoperative risk in non diabetics also
UK: A recent study, published in the journal Anaesthesia has found an association between high blood sugar and increased risk of postoperative complications in those without diabetes. However, after adjusting for comorbid disease, the strength of this association was reduced and no longer significant.
"Our findings, therefore, suggest that optimization of pre-existing morbidity should be prioritized over reducing glycated hemoglobin (HbA1c) in patients without diabetes in order to prevent adverse postoperative outcomes," S. Lam, Norwich Medical School, University of East Anglia, Norwich, UK, and colleagues wrote in their study.
The study was conducted with the aim to clarify the association between HbA1c and postoperative outcomes in people without diabetes across all major surgical specialties in a large prospective cohort study design with adequate control of potential confounding factors.
For this purpose, the researchers recruited half a million adults into the UK Biobank prospective cohort study between March 2006 and October 2010. Participants were divided into three groups: no diagnosis of diabetes and HbA1c < 42 mmol.mol−1; no diagnosis of diabetes and elevated HbA1c (≥ 42 mmol.mol−1 with no upper limit); and prevalent diabetes (regardless of HbA1c concentration) at recruitment.
The participants were followed by linkage with routinely collected hospital data to determine any surgical procedures undertaken after recruitment and the associated postoperative outcomes. A composite primary outcome of 30-day major postoperative complications and 90-day all-cause mortality was the main outcome measure. To estimate the odds of the primary outcome by group, logistic regression was used. Analyses were limited to those who underwent surgery within one year of recruitment (n = 26,653).
Based on the analysis, the researchers found the following:
- In a combined effects logistic regression model, participants not known to have diabetes with HbA1c ≥ 42 mmol.mol−1 had increased odds of the primary outcome (OR 1.43), when compared with those without diabetes and HbA1c < 42 mmol.mol−1. This effect was attenuated and no longer statistically significant in a direct effects model with adjustment for hyperglycemia-related comorbidity (OR 1.37).
- Elevated pre-operative HbA1c in people without diabetes may be associated with an increased risk of complications, but the association is likely confounded by end-organ comorbidity.
To conclude, the researchers wrote, "in contrast to previous evidence, our findings suggest that to prevent adverse postoperative outcomes, optimization of pre-existing morbidity should take precedence over reducing HbA1c in people without diabetes."
"Wider use of pre-operative HbA1c measurement is suggested to inform wider peri-operative care, particularly in those with risk factors for developing diabetes," they concluded.
Reference:
The study titled, "Glycated haemoglobin and the risk of postoperative complications in people without diabetes: a prospective population-based study in UK Biobank," was published in the journal Anaesthesia.
DOI: https://doi.org/10.1111/anae.15684
KEYWORDS: Anaesthesia journal, blood sugar, glycated hemoglobin, postoperative complications, HbA1c, S. Lam, comorbid disease, hyperglycemia, morbidity, risk factors
