ArticleJournal of epidemiology and community health1998
Effects of changes in smoking status on risk estimates for myocardial infarction among women recruited for the Royal College of General Practitioners' Oral Contraception Study in the UK.
Article in Journal of epidemiology and community health, 1998. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 11 papers, 1 of them a synthesis that pooled it.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Who cites it
11 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Combined oral contraceptives: the risk of myocardial infarction and ischemic stroke.The Cochrane database of systematic reviews · 2015Pooled it
- Re-Evaluating the Association Between Hormonal Contraception and Breast Cancer Risk.Breast cancer (Dove Medical Press) · 2023Review
- Smoking in young women in Scotland and future burden of hospital admission and death: a nested cohort study.The British journal of general practice : the journal of the Royal College of General Practitioners · 2013Article
- Impact of lifestyle in middle-aged women on mortality: evidence from the Royal College of General Practitioners' Oral Contraception Study.The British journal of general practice : the journal of the Royal College of General Practitioners · 2010Article
- Mortality among contraceptive pill users: cohort evidence from Royal College of General Practitioners' Oral Contraception Study.BMJ (Clinical research ed.) · 2010Article
- Cancer risk among users of oral contraceptives: cohort data from the Royal College of General Practitioner's oral contraception study.BMJ (Clinical research ed.) · 2007Article
- Long term effects of hysterectomy on mortality: nested cohort study.BMJ (Clinical research ed.) · 2005Article
- Increased mortality among women with Rose angina who have not presented with ischaemic heart disease.The British journal of general practice : the journal of the Royal College of General Practitioners · 2003Article
- Pain and subsequent mortality and cancer among women in the Royal College of General Practitioners Oral Contraception Study.The British journal of general practice : the journal of the Royal College of General Practitioners · 2003Article
- Stopping smoking and body weight in women living in the United Kingdom.The British journal of general practice : the journal of the Royal College of General Practitioners · 1999Article
- Mortality associated with oral contraceptive use: 25 year follow up of cohort of 46 000 women from Royal College of General Practitioners' oral contraception study.BMJ (Clinical research ed.) · 1999Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
5 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
STUDY
objectiveTo determine whether changes in smoking status among women recruited for the Royal College of General Practitioners' Oral Contraception Study affected previous risk estimates for myocardial infarction.
design(1) Postal survey between November 1994 and July 1995 of women still under general practitioner observation. Validation of the smoking information supplied by the women on the questionnaire by comparison with that reported by the general practitioner at recruitment to the main study. (2) Nested case-control study of 103 cases of myocardial infarction, matched with 309 controls, to see if different risk estimates were obtained when smoking status at recruitment or smoking status at time of event were used in the analysis.
setting650 general practices throughout the United Kingdom.
participants10,073 women who responded to the questionnaire (85.4% of 11,797 sent out). MAIN
resultsThere was good agreement between smoking information recorded by the general practitioner at recruitment and that supplied retrospectively by respondents to the questionnaire. The risk estimates for myocardial infarction associated with use of combined oral contraceptives (COCs) were almost identical irrespective of whether smoking status at recruitment or at time of event was used for the statistical adjustment. This was because few women stopped smoking while also using COCs. In fact, fewer regular smokers who have ever used COCs reported stopping smoking than never users. The risk estimates for myocardial infarction associated with smoking were smaller when smoking habits at recruitment was used than when smoking habits at time of event was used.
conclusionsPrevious results from the Oral Contraception Study regarding the effects of COCs are unlikely to have been biased by changes in the smoking habits of the cohort, but the effects of smoking have probably been underestimated. There is still a need for effective health education regarding the risks associated with smoking, particularly among users of COCs.
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