Nonobese postmenopausal women with diabetes at risk of kidney cancer

Diabetes bears an increased hazard of developing kidney cancer among postmenopausal women, but this association is only limited to those without obesity, a study has shown.

The analysis included 36,975 women (mean age, 61.7 years), of whom 2,353 (6.4 percent) reported having diabetes at baseline. An additional 3,140 (8.5 percent) women developed diabetes over 25 years of follow-up.

Overall, women with vs without diabetes had a slightly higher body mass index (BMI) and waist-to-hip ratio (WHR), were more likely to have hypertension and use diuretics, and were less likely to engage in high/moderate physical activity and consume alcohol, calcium, and vitamin E.

In age-adjusted Cox proportional hazards model, diabetes was associated with an increased risk of kidney cancer (hazard ratio [HR], 1.76, 95 percent confidence interval [CI], 1.26–1.45). However, this association disappeared after further adjustments for BMI, WHR, hypertension, physical activity, diuretic use, pack-years of smoking, alcohol intake, and total caloric intake (HR, 1.35, 95 percent CI, 0.94–1.94).

Interestingly, the risk increase seen for kidney cancer persisted among diabetic women with a waist circumference <34.6 inches (HR, 2.18, 95 percent CI, 1.08–4.38) or with BMI <30 kg/m² (HR, 1.82, 95 percent CI, 1.10–3.00).

While the present data should be validated in a larger sample, researchers stressed that nonobese postmenopausal women who develop new-onset diabetes should undergo a more thorough surveillance for cancer.