Use of hormone replacement therapy and risk of breast cancer: nested case-control studies using the QResearch and CPRD databases.

ABSTRACT:

Objective

To assess the risks of breast cancer associated with different types and durations of hormone replacement therapy (HRT).

Design

Two nested case-control studies.

Setting

UK general practices contributing to QResearch or Clinical Practice Research Datalink (CPRD), linked to hospital, mortality, social deprivation, and cancer registry (QResearch only) data.

Participants

98 611 women aged 50-79 with a primary diagnosis of breast cancer between 1998 and 2018, matched by age, general practice, and index date to 457 498 female controls.

Main outcome measures

Breast cancer diagnosis from general practice, mortality, hospital, or cancer registry records. Odds ratios for HRT types, adjusted for personal characteristics, smoking status, alcohol consumptio

SUBMITTER: Vinogradova Y 

PROVIDER: S-EPMC7592147 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature