Mean plasma glucose concentrations increased by 0.5 mg/dL for each cigarette smoked per day.
Previous studies have linked smoking to the risk of type 2 diabetes, the authors point out, but the relationship between smoking and diabetes remains unclear.
Dr. Lucinda J. England from National Institute of Child Health and Human Development, Bethesda, Maryland and colleagues used data from a preeclampsia prevention trial, involving more than 4,500 women, to investigate.
Mean 1-hour plasma glucose concentrations were highest among women who smoked at study enrollment, the authors report, and were lowest among women who never smoked or who quit before or during pregnancy.
Mean plasma glucose concentrations increased by 0.5 mg/dL for each cigarette smoked per day. However, there was no relationship between 1-hour plasma glucose concentration and the average number of cigarettes smoked per day or the pack-years of smoking.
Gestational diabetes, as diagnosed by a 3-hour oral glucose tolerance test, was highest among women who smoked at study enrollment (4.4%) and lowest among those who had never smoked (1.8%), the investigators note. Women who quit before or during pregnancy had intermediate rates of gestational diabetes (1.9% and 2.5%).
If the association between smoking and gestational diabetes mellitus is causal, the researchers write, "then 47% of gestational diabetes mellitus in smokers and 10% in all women in our study population could potentially be attributed to tobacco exposure."
Thus, they conclude, "smoking may be an important modifiable risk factor for gestational diabetes mellitus."
Am J Epidemiol 2004;160:1205-1213.
In the last 50 years health care systems throughout the world have faced a new epidemic dual disease: cardiovascular disease (CVD)-diabetes mellitus. Nowadays, CVD is the leading cause of death in all western countries, and 60% of deaths for ischemic heart disease and stroke occur in developing countries. Recent and compelling evidence has shown the significant and independent role of inflammation, insulin resistance and subsequent endothelial dysfunction in the initiation and progression of atherothrombosis, superimposed on traditional risk factors.
Herz. 2004 Dec;29(8):749-759.