Title: Angiotensin-Receptor Blockade and Risk of Cancer: Meta-Analysis of Randomised Controlled Trials
Topic: General Cardiology
Date Posted: 6/14/2010
Author(s): Sipahi I, Debanne SM, Rowland DY, Simon DI, Fang JC.
Citation: Lancet Oncol 2010;Jun 14:[Epub ahead of print].
Clinical Trial: No
Study Question: Are angiotensin-receptor blockers (ARBs) associated with increased risk for cancer?
Methods: This was a meta-analysis, including all publicly available data for the development of cancers from randomized controlled trials of ARBs. From the 2,057 reports identified (1,531 from Medline, 503 from Scopus, and 23 from Cochrane databases), 1,997 reports were excluded. Exclusion criteria included duration of the trial <1 year, <100 patients, use of ARBs in all groups, nonrandomized trial design, or lack of information on cancers. A total of nine trials were included in the final analysis, of which five had data on new cancer occurrences, five had information on common types of specific solid-organ cancers, and eight had information on cancer death. The primary outcome of interest was incident cancer, with a secondary outcome of interest being occurrence of specific solid-organ cancers.
Results: Telmisartan was the study drug for 85.7% of patients (n = 30,014) who received an ARB in randomized controlled trials that had data on cancer outcomes. Patients randomized to ARBs had a significant increased risk for new cancers, as compared with patients in the control groups (7.2% vs. 6.0%; relative risk [RR], 1.08; 95% confidence interval [CI], 1.01-1.15). After limiting the analysis to trials with cancer as a prespecified endpoint, the RR was 1.11 (95% CI, 1.04-1.18). For solid organ cancers, only new lung cancer was significantly higher among patients randomized to ARBs compared to controls (0.9% vs. 0.7%; RR, 1.25; 95% CI, 1.05-1.49). No statistically significant difference in cancer deaths was observed between patients randomized to ARBs as compared to controls (1.8% vs. 1.65; RR, 1.07; 95 CI, 0.97-1.18).
Conclusions: The investigators concluded that this meta-analysis of randomized controlled trials observed a modest association between ARBs and cancer risk. Further investigation would be needed to understand the potential risk associated with particular drugs.
Perspective: This meta-analysis provides some interesting findings regarding use of ARBs and risk of cancer, which suggests a modest increase in cancer risk. Understanding the risk and benefits of ARBs in patients can be further investigated to determine if specific patients are at increased risk for cancers. Elizabeth A. Jackson, M.D., F.A.C.C.
Title: White Rice, Brown Rice, and Risk of Type 2 Diabetes in US Men and Women
Topic: Prevention/Vascular
Date Posted: 6/14/2010 4:00:00 PM
Author(s): Sun Q, Spiegelman D, van Dam RM, et al.
Citation: Arch Intern Med 2010;170:961-969.
Clinical Trial: No
Study Question: Is rice consumption associated with risk of type 2 diabetes?
Methods: Subjects enrolled in three prospective cohorts were used for the present analysis. Men from the Health Professionals Follow-up Study (age range, 32-87 years) were included, in addition to women from the Nurses’ Health Study (age range, 26-45 years) and Nurses’ Health Study II (age range, 26-45 years). Subjects were excluded if they had a history of cardiovascular disease or cancer at baseline. Five categories of white rice intake were created, ranging from <1 serving per month, to ≥5 servings per week. Three categories of brown rice were created, ranging from <1 serving per month to ≥2 servings per week.
Results: A total of 39,765 men and 157,463 women were included in this analysis. Over the 20 years of follow-up, 2,648 cases of type 2 diabetes were observed in the Health Professionals Follow-up Study cohort. In the original Nurses’ Health Study cohort, 5,550 cases were observed over 22 years of follow-up, and in the Nurses’ Health Study II cohort, 2,359 cases were observed during 14 years of follow-up. After adjustment for age, diet, and lifestyle factors such as physical activity, intake of white rice (≥5 servings per week vs. <1 per month) was associated with a higher risk for type 2 diabetes. The pooled relative risk was 1.7 (95% CI, 1.02-1.36). In contrast, intake of brown rice appeared protective, with a relative risk of 0.89 (95% confidence interval [CI], 0.81-0.97) for high intake (≥2 servings per week) compared to low intake (<1 serving per month). Replacing 50 g/day of white rice in the diet with the same amount of brown rice was estimated to lower the risk of type 2 diabetes by 16% (95% CI, 9%-21%). The same replacement of whole grains as a group was estimated to be associated with a 36% (95% CI, 30%-42%) lower risk for type 2 diabetes.
Conclusions: The investigators concluded that substitution of whole grains, including brown rice for white rice, lowers risk of type 2 diabetes.
Perspective: These findings provide further evidence for recommending whole grains (including brown rice) to patients at risk for diabetes. Dietary changes can have a significant impact on cardiovascular disease prevention; health care providers can use findings from studies such as this to educate their patients regarding healthy dietary practices. Elizabeth A. Jackson, M.D., F.A.C.C.