Study
PLCO
(Learn more about this study)
Project ID
2007-0054
Initial CDAS Request Approval
Feb 15, 2008
Title
Energy Balance, Mortality and Healthy Survival
Summary
Energy restriction, also known as caloric restriction, is the only intervention in animal studies known to reduce all-cause mortality and consistently increase both mean and maximum lifespan (defined as age at death of the longest-lived 10% of the species) (Willcox et al, 2004). This suggests that energy restriction acts through pathways that affect aging itself, and appears to also reduce risk for age-associated diseases, such as cancer. Chang, Ziegler, Dunn et al. (2006) showed in the PLCO cohort that energy balance, which is achieved by a combination of low energy intake and/or high physical activity, is significantly associated with reduced breast cancer risk, even after adjusting for current body mass index (BMI) and recent physical activity. They also showed that when estimating the joint effect of energy intake, BMI, and physical activity, women with the most positive energy balance had more than twice the risk of breast cancer of women with the lowest energy balance. In the current study, we wish to determine whether energy balance has an association with mortality and the three major causes of mortality (CHD-coronary heart disease, cancer, stroke). We also wish to test whether energy balance predicts healthy survival. We would use prospectively collected dietary data from the baseline DQx, which was administered ~4 years after baseline. In addition, we will explore the relative contributions of recent BMI, BMI at 50 y, BMI at 20 y, recent weight gain, adult weight gain, and height with respect to these phenotypes (mortality, cause-specific mortality and healthy survival) with emphasis on independent and joint effects. We anticipate that factors that suggest positive energy balance will be associated with increased risk.
Note: Additional work related to this project is being continued in <a href="/cdas/plco/pubs_projects/project/553/">PLCO-26</a>
Aims
1) We will study the independent and joint effects of energy intake, current BMI, and recent physical activity on mortality risk (including cause-specific mortality for CHD, cancer, stroke) and risk for healthy survival in the screening arm of the PLCO Trial. Energy intake and physical activity will be estimated with the DQX, which was administered at baseline to subjects assigned to screening. 2) We will also use the DHQ, administered ~ four years after baseline to subjects assigned to both arms of the PLCO Trial, to estimate energy intake. This will allow us to investigate the independent and joint effects of energy intake, current BMI, and physical activity on mortality, cause-specific mortality and healthy survival. 3) We will investigate the independent and joint effects of current BMI, BMI at age 50, BMI at age 20, adult weight gain, recent weight gain, and height on these phenotypes in both arms of the Trial. 4) We will also stratify the data by smoking status to assess whether effects of energy intake are stronger in never smokers.
Collaborators
Lance Yokochi (PHRI Hawaii)
Qimei He (PHRI Hawaii)
Randy Chen (PHRI Hawaii)
Regina Ziegler (EBP/DCEG/NCI)
