Statin use, hyperlipidaemia, and the risk of breast cancer.
Hydroxymethyl glutaryl coenzyme A inhibitors ("statins") are carcinogenic in rodents and an increased incidence of breast cancer was reported among pravastatin users in one randomised trial. We conducted a case-control study in the General Practice Research Database to evaluate the risk of breast cancer among 50- to 79-year old women treated with statins for hyperlipidaemia. Case and control women were matched by age, general practice, duration of prescription history in the General Practice Research Database, and index date. Adjusting for history of benign breast disease, body mass index, and use of hormone replacement therapy, women currently treated with statins had an estimated relative risk for breast cancer of 1.0 (95% confidence interval 0.6-1.6) compared to women without hyperlipidaemia. Untreated hyperlipidaemia was associated with an increased risk of breast cancer (estimated relative risk 1.6; 95% confidence interval 1.1-2.5). The estimated relative risk among women currently receiving only non-statin lipid-lowering drugs was similar to that of women with untreated hyperlipidaemia (1.8; 95% confidence interval 0.9-3.4). We found no evidence for an increasing trend in breast cancer risk with increasing duration of statin use (median duration 1.8 years, maximum 8.6 years).
Kaye
J A
JA
Department of Epidemiology, Harvard School of Public Health, 677 Huntington Avenue, Boston, MA 02115, USA. jkaye@bu.edu
Meier
C R
CR
Walker
A M
AM
Jick
H
H
D000368:Aged; D000924:Anticholesteremic Agents / Q000009:adverse effects* / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000453:epidemiology* / Q000209:etiology*; D016022:Case-Control Studies; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D006949:Hyperlipidemias / Q000150:complications* / Q000188:drug therapy*; D008875:Middle Aged; D017035:Pravastatin / Q000009:adverse effects / Q000627:therapeutic use; D012307:Risk Factors
D000924:Anticholesteremic Agents; D017035:Pravastatin