Exposure to bisphosphonates and risk of cancer: a protocol for nested caseecontrol studies using the QResearch primary care database

Vinogradova, Yana; Coupland, Carol; Hippisley-Cox, Julia

Abstract

Introduction: Bisphosphonates are becoming
a common treatment for osteoporosis particularly after
discovery of the association between hormone
replacement therapy and increased risk of breast
cancer. As osteoporosis develops with age, treatment
is a long-term intervention. Randomised control trials
typically have limited follow-up times, which restricts
investigation of the effects of the drugs on risk of
primary cancers. A few observational studies have
demonstrated a reduced risk of breast cancer and
possibly of endometrial cancer in bisphosphonate
users. Two epidemiological studies have studied the
effect of the drugs on oesophageal cancer but did not
reach any definite conclusions. So far, no effects on
colorectal and stomach cancer have been shown. This
study will investigate the association of
bisphosphonates with risks of the 10 most common
primary cancers.
Methods and analysis: A series of nested
caseecontrol studies will be based on the general
population using records from 660 UK general
practices within the QResearch Database. Cases will be
patients with primary cancers diagnosed between
1996 and 2011. Each case will be matched by age, sex,
practice and calendar year to five controls, who are
alive and registered with the practice at the time of
diagnosis of the case. Exposure to bisphosphonates
will be defined as at least one prescription during the
study period. For the most common cancers with
substantial numbers of observations, the effect of the
duration of the treatment and different types of
bisphosphonates will be studied. Conditional logistic
regression will be applied to produce ORs adjusted for
smoking status, socioeconomic status, ethnicity,
cancer-specific co-morbidities and use of other
medications.

Citation

Vinogradova, Y., Coupland, C., & Hippisley-Cox, J. (2012). Exposure to bisphosphonates and risk of cancer: a protocol for nested caseecontrol studies using the QResearch primary care database. BMJ Open, 2(1), Article e000548. https://doi.org/10.1136/bmjopen-2011-000548

• Journal Article Type: Article
• Publication Date: Jan 12, 2012
• Deposit Date: Apr 22, 2014
• Publicly Available Date: Apr 22, 2014
• Journal: BMJ Open
• Electronic ISSN: 2044-6055
• Publisher: BMJ Publishing Group
• Peer Reviewed: Peer Reviewed
• Volume: 2
• Issue: 1
• Article Number: e000548
• DOI: https://doi.org/10.1136/bmjopen-2011-000548
• Public URL: https://nottingham-repository.worktribe.com/output/709113
• Publisher URL: http://bmjopen.bmj.com/content/2/1/e000548