Estimating the global cancer burden due to low levels of physical activity

Rationale

Around 40% of all cancers are thought to be avoidable by modification of lifestyle factors. Obesity has been found to be a risk factor for several cancers and was estimated to have caused around 3.6% of all new cancers which occurred in 2012. There is now an emerging evidence base which shows that low levels of physical activity can increase the risk of cancer. The World Cancer Research Fund (WCRF), as part of their continuous update project, have concluded that there is strong evidence that high levels of physical activity decreases the risk of cancers of the breast, endometrium and colon and rectum. In addition, we have recently shown using common genetic variation (a technique called Mendelian randomization) that physical activity protects against prostate, colorectal and breast cancer risk. In our analyses we found larger protective effects of physical activity on cancers of the breast, prostate, colon and rectum than were estimated by observational studies. It is possible that cancers at other sites are similarly influenced by physical activity but they have not yet been investigated in this way.

Aims & Objectives

The aims of the project are to:

1. Identify the patterns of physical activity which are most likely to be causing cancer using wrist-worn accelerometer data and cancer outcomes in UK Biobank.

2. Test whether low levels of physical activity is a causal risk factor for cancer at several sites using Mendelian randomization and data from large cancer consortia

3. Use the best publicly available data to estimate the global prevalence of low levels of physical activity by country/region/ethnicity.

4. Estimate the global burden of cancer attributable to low levels of physical activity using cancer surveillance data compiled by IARC broken down by country/region and cancer type.

Methods

The student will be access wrist worn accelerometry data from UKBiobank or other similar population based cohorts. The student will characterised in a variety of different ways in order to investigate different features or patterns in behaviour and will use epidemiological techniques to understand the relationship between patterns of activity and cancer.

The student will be trained on the theory and application of Mendelian radomization and will use this to determine which cancers are caused by low levels of physical activity (and other patterns of physical activity).

The student will receive training in the interpretation of cancer registry data and will use this data alongside global data on physical activity to determine the proportion of cancers which can be attributed to insufficient physical activity worldwide.

How to apply for this project

This project will be based in Bristol Medical School - Population Health Sciences in the Faculty of Health Sciences at the University of Bristol.

If you have secured your own sponsorship or can self-fund this PhD please visit our information page here for further information on the department of Population Health Science and how to apply.