Glycaemic index, glycaemic load and risk of endometrial cancer: a prospective cohort study.
OBJECTIVE
High-glycaemic-load diets may increase endometrial cancer risk by increasing circulating insulin levels and, as a consequence, circulating oestrogen levels. Given the paucity of epidemiological data regarding the relationship between dietary glycaemic index and glycaemic load and endometrial cancer risk, we sought to examine these associations using data from a prospective cohort study.


METHODS
We examined the association between dietary glycaemic load and endometrial cancer risk in a cohort of 49,613 Canadian women aged between 40 and 59 years at baseline who completed self-administered food-frequency questionnaires between 1982 and 1985. Linkages to national mortality and cancer databases yielded data on deaths and cancer incidence, with follow-up ending between 1998 and 2000.


RESULTS
During a mean of 16.4 years of follow-up, we observed 426 incident cases of endometrial cancer. Hazard ratios for the highest versus the lowest quartile level of overall glycaemic index and glycaemic load were 1.47 (95% confidence interval (CI) = 0.90-2.41; P for trend = 0.14) and 1.36 (95% CI = 1.01-1.84; P for trend = 0.21), respectively. No association was observed between total carbohydrate or total sugar consumption and endometrial cancer risk. Among obese women (body mass index >30 kg m(-2)) the hazard ratio for the highest versus the lowest quartile level of glycaemic load was 1.88 (95% CI = 1.08-3.29; P for trend = 0.54) and there was a 55% increased risk for the highest versus the lowest quartile level of glycaemic load among premenopausal women. There was also evidence to support a positive association between glycaemic load and endometrial cancer risk among postmenopausal women who had used hormone replacement therapy.


CONCLUSIONS
Our data suggest that diets with high glycaemic index or high glycaemic load may be associated with endometrial cancer risk overall, and particularly among obese women, premenopausal women and postmenopausal women who use hormone replacement therapy.
Silvera
Stephanie A N
SA
Department of Epidemiology and Population Health, Albert Einstein College of Medicine, Bronx, NY 10461, USA. ssilvera@aecom.yu.edu
Rohan
Thomas E
TE
Jain
Meera
M
Terry
Paul D
PD
Howe
Geoffrey R
GR
Miller
Anthony B
AB
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D002170:Canada / Q000453:epidemiology; D015331:Cohort Studies; D004040:Dietary Carbohydrates / Q000378:metabolism*; D016889:Endometrial Neoplasms / Q000453:epidemiology* / Q000209:etiology*; D005260:Female; D005500:Follow-Up Studies; D038321:Glycemic Index; D020249:Hormone Replacement Therapy / Q000009:adverse effects; D006801:Humans; D015994:Incidence; D008593:Menopause / Q000502:physiology; D008875:Middle Aged; D009765:Obesity / Q000150:complications*; D011446:Prospective Studies; D012306:Risk; D012307:Risk Factors; D011795:Surveys and Questionnaires
D001786:Blood Glucose; D004040:Dietary Carbohydrates