Research due in an upcoming issue of the British Medical Journal found that smokers had a greater risk of developing glucose intolerance than people who never smoked. But another finding of the study is raising eyebrows - that people exposed to secondhand smoke also experienced an increased risk for the condition.The study, begun in 1985, followed 4,572 young men and women (age 18 to 30 at baseline) in four American cities for up to 15 years.
After adjusting for confounders (factors that could also influence development of glucose tolerance - age, sex, race, education, income, blood pressure, body mass index, triglycerides, and alcohol intake), researchers found, when compared to people who never smoked and had no passive smoke exposure:
- Current smokers (average 10 cigarettes/day) had a 65% greater risk of developing prediabetes.
- People who never smoked but were exposed to secondhand smoke (average 12.6 hours/week) had a 35% greater risk of developing prediabetes.
Prediabetes, also known as impaired glucose tolerance, was recorded when serum glucose ≥ 100 mg/dl and < 126 mg/dl. (Diabetes is diagnosed when fasting serum glucose ≥ 126 mg/dl.) Most people with prediabetes will develop full blown diabetes unless they make lifestyle changes.
Researchers said substances in cigarette smoke which are damaging to the pancreas may be present in higher concentrations in secondhand smoke, since passive smoke is produced under different temperatures and chemical conditions.
Some news summaries:
Secondhand Smoke Linked to Diabetes Risk
Passive Smoke Could Prompt Diabetes Precursor: Report
Smoking Linked to Glucose Intolerance in Young Adults
For the study abstract:
Active and passive smoking and development of glucose intolerance among young adults in a prospective cohort: CARDIA study
For the study (pdf):
Active and passive smoking and development of glucose intolerance among young adults in a prospective cohort: CARDIA study
