A retrospective cohort study has shown that people with type 2 diabetes who gave up smoking for a period of at least 1 year had a small but significant deterioration in glycaemic control that lasted for up to 3 years. This disruption was independent of the weight gain that typically follows smoking cessation.
The authors evaluated 10 692 adult smokers with type 2 diabetes who were enrolled in THIN (The Health Improvement Network), a large primary care database in the UK. Of these, 3131 (29%) quit smoking for a year or more. Compared with those who did not quit, these participants had an increase in mean HbA1c of 2.34 mmol/mol (0.21%) after adjustment for age, gender, social deprivation, diabetes duration, medications, baseline body weight and change in body weight. This increase took place over the first year and then gradually reduced to the levels of the continuous smokers over the subsequent 2 years.
Deborah Lycett, the lead study author, said: “Knowing that deterioration in blood glucose control occurs around the time of stopping smoking helps to prepare those with diabetes and their clinicians to be proactive in tightening their glycaemic control during this time.
“Stopping smoking is crucial for preventing complications that lead to early death in those with diabetes. So people with diabetes should continue to make every effort to stop smoking, and at the same time they should expect to take extra care to keep their blood glucose well controlled and maximise the benefits of smoking cessation.”
The article can be read in full at The Lancet Diabetes & Endocrinology here.
An accompanying editorial can be found here.
