Smoking and mortality among women with type 2 diabetes: The Nurses' Health Study cohort.
OBJECTIVE
To assess the relationship between cigarette smoking and mortality among women with type 2 diabetes in the Nurses' Health Study cohort.


METHODS
The Nurses' Health Study, a prospective cohort of U.S. female registered nurses, included 7,401 women with type 2 diabetes diagnosed at baseline or during follow-up from 1976 to 1996. Total and cause-specific mortality of these diabetic women were the outcomes of interest.


RESULTS
We documented 724 deaths during 20 years of follow-up (67,420 person-years) among women with type 2 diabetes. In multivariate analyses, adjusting for age, history of high blood pressure and high cholesterol, and other cardiovascular risk factors, compared with never smokers, the RRs of mortality were 1.31 (95% CI 1.11-1.55) for past smokers, 1.43 (0.96-2.14) for current smokers of 1-14 cigarettes/day, 1.64 (1.24-2.17) for current smokers of 15-34 cigarettes/day, and 2.19 (1.32-3.65) for current smokers of > or =35 cigarettes/day (P for trend = 0.0002). Women with type 2 diabetes who had stopped smoking for > or =10 years had a mortality RR of 1.11 (0.92-1.35) compared with diabetic women who were never smokers.


CONCLUSIONS
Cigarette smoking is associated in a dose-response manner with an increased mortality among women with type 2 diabetes. Furthermore, quitting smoking appears to decrease this excess risk substantially. Diabetes patients should be strongly advised against smoking.
Al-Delaimy
W K
WK
Department of Nutrition, Harvard School of Public Health, Boston, MA 02115, USA. wael@hsph.harvard.edu
Willett
W C
WC
Manson
J E
JE
Speizer
F E
FE
Hu
F B
FB
D000328:Adult; D001794:Blood Pressure; D015992:Body Mass Index; D002318:Cardiovascular Diseases / Q000150:complications / Q000401:mortality; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000401:mortality*; D005260:Female; D006306:Health Surveys; D006801:Humans; D006937:Hypercholesterolemia / Q000150:complications; D006973:Hypertension / Q000150:complications; D008875:Middle Aged; D009369:Neoplasms / Q000150:complications / Q000401:mortality; D009726:Nurses; D011446:Prospective Studies; D012307:Risk Factors; D012907:Smoking / Q000401:mortality*; D011795:Surveys and Questionnaires