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

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, mort...

Full description

Bibliographic Details
Main Authors: Vinogradova, Y, Coupland, C, Hippisley-Cox, J
Format: Journal article
Language:English
Published: British Medical Journal Publishing Group 2020
_version_ 1824459119454584832
author Vinogradova, Y
Coupland, C
Hippisley-Cox, J
author_facet Vinogradova, Y
Coupland, C
Hippisley-Cox, J
author_sort Vinogradova, Y
collection OXFORD
description 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 consumption, comorbidities, family history, and other prescribed drugs. Separate results from QResearch or CPRD were combined. Results: Overall, 33 703 (34%) women with a diagnosis of breast cancer and 134 391 (31%) controls had used HRT prior to one year before the index date. Compared with never use, in recent users (<5 years) with long term use (≥5 years), oestrogen only therapy and combined oestrogen and progestogen therapy were both associated with increased risks of breast cancer (adjusted odds ratio 1.15 (95% confidence interval 1.09 to 1.21) and 1.79 (1.73 to 1.85), respectively). For combined progestogens, the increased risk was highest for norethisterone (1.88, 1.79 to 1.99) and lowest for dydrogesterone (1.24, 1.03 to 1.48). Past long term use of oestrogen only therapy and past short term (<5 years) use of oestrogen-progestogen were not associated with increased risk. The risk associated with past long term oestrogen-progestogen use, however, remained increased (1.16, 1.11 to 1.21). In recent oestrogen only users, between three (in younger women) and eight (in older women) extra cases per 10 000 women years would be expected, and in oestrogen-progestogen users between nine and 36 extra cases per 10 000 women years. For past oestrogen-progestogen users, the results would suggest between two and eight extra cases per 10 000 women years. Conclusion: This study has produced new generalisable estimates of the increased risks of breast cancer associated with use of different hormone replacement preparations in the UK. The levels of risks varied between types of HRT, with higher risks for combined treatments and for longer duration of use.
first_indexed 2025-02-19T04:36:43Z
format Journal article
id oxford-uuid:ac7a903a-d09c-4ea9-97bb-26999f8ae310
institution University of Oxford
language English
last_indexed 2025-02-19T04:36:43Z
publishDate 2020
publisher British Medical Journal Publishing Group
record_format dspace
spelling oxford-uuid:ac7a903a-d09c-4ea9-97bb-26999f8ae3102025-02-01T20:10:04ZUse of hormone replacement therapy and risk of breast cancer: nested case-control studies using the QResearch and CPRD databasesJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:ac7a903a-d09c-4ea9-97bb-26999f8ae310EnglishJisc Publications RouterBritish Medical Journal Publishing Group2020Vinogradova, YCoupland, CHippisley-Cox, JObjective: 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 consumption, comorbidities, family history, and other prescribed drugs. Separate results from QResearch or CPRD were combined. Results: Overall, 33 703 (34%) women with a diagnosis of breast cancer and 134 391 (31%) controls had used HRT prior to one year before the index date. Compared with never use, in recent users (<5 years) with long term use (≥5 years), oestrogen only therapy and combined oestrogen and progestogen therapy were both associated with increased risks of breast cancer (adjusted odds ratio 1.15 (95% confidence interval 1.09 to 1.21) and 1.79 (1.73 to 1.85), respectively). For combined progestogens, the increased risk was highest for norethisterone (1.88, 1.79 to 1.99) and lowest for dydrogesterone (1.24, 1.03 to 1.48). Past long term use of oestrogen only therapy and past short term (<5 years) use of oestrogen-progestogen were not associated with increased risk. The risk associated with past long term oestrogen-progestogen use, however, remained increased (1.16, 1.11 to 1.21). In recent oestrogen only users, between three (in younger women) and eight (in older women) extra cases per 10 000 women years would be expected, and in oestrogen-progestogen users between nine and 36 extra cases per 10 000 women years. For past oestrogen-progestogen users, the results would suggest between two and eight extra cases per 10 000 women years. Conclusion: This study has produced new generalisable estimates of the increased risks of breast cancer associated with use of different hormone replacement preparations in the UK. The levels of risks varied between types of HRT, with higher risks for combined treatments and for longer duration of use.
spellingShingle Vinogradova, Y
Coupland, C
Hippisley-Cox, J
Use of hormone replacement therapy and risk of breast cancer: nested case-control studies using the QResearch and CPRD databases
title Use of hormone replacement therapy and risk of breast cancer: nested case-control studies using the QResearch and CPRD databases
title_full Use of hormone replacement therapy and risk of breast cancer: nested case-control studies using the QResearch and CPRD databases
title_fullStr Use of hormone replacement therapy and risk of breast cancer: nested case-control studies using the QResearch and CPRD databases
title_full_unstemmed Use of hormone replacement therapy and risk of breast cancer: nested case-control studies using the QResearch and CPRD databases
title_short Use of hormone replacement therapy and risk of breast cancer: nested case-control studies using the QResearch and CPRD databases
title_sort use of hormone replacement therapy and risk of breast cancer nested case control studies using the qresearch and cprd databases
work_keys_str_mv AT vinogradovay useofhormonereplacementtherapyandriskofbreastcancernestedcasecontrolstudiesusingtheqresearchandcprddatabases
AT couplandc useofhormonereplacementtherapyandriskofbreastcancernestedcasecontrolstudiesusingtheqresearchandcprddatabases
AT hippisleycoxj useofhormonereplacementtherapyandriskofbreastcancernestedcasecontrolstudiesusingtheqresearchandcprddatabases