Women who experience early natural menopause, or surgical menopause, may be prone to any morbidity and mortality risk related to oestrogen deficiency. The thesis aimed to explore the long-term sequelae of the menopause by investigating current knowledge about the relationship between early age at natural menopause, any surgical menopause, and early age at surgical menopause, and future mortality, incident cancer, and incident circulatory disease. The thesis also investigated the long-term sequelae of menopause using data from a nested cohort of UK women from the Royal College of General Practitioners’ Oral Contraception Study [RCGP OCS]. Methods A portfolio of systematic reviews was conducted. To assess whether a young age at natural menopause, any surgical menopause, and a young age at surgical menopause were associated with mortality and ill-health, data from the RCGP OCS were analysed using Cox regression and competing risks. Results Systematic reviews: 153 papers were included, of varying quality. The heterogeneity of included studies’ exposure and reference groups meant that meta-analysis was not possible. Younger age at natural menopause was strongly associated with an increased risk of all-cause mortality, but not cancer-related death. A suggestion of an increased risk was found for cardiovascular death. Young natural menopause protected strongly against incident endometrial and weakly against ovarian cancers. Few studies examined cervical cancer and age at natural menopause was not a risk factor. Colorectal cancer was not consistently associated with age at natural menopause. Young age at natural menopause was associated with an increased risk of coronary heart disease [CHD], but not cerebrovascular disease. Little evidence was found that surgical, compared with natural menopause was associated with any mortality outcomes. Surgical menopause tended to protect against ovarian cancer but no effect was found for cervical cancer. The relationship between colorectal cancer, or cerebrovascular disease, and surgical menopause is unclear. More evidence showed that surgical menopause may increase the risk of CHD. Limited evidence for young age at combined natural and surgical menopause found it to increase the risk of all-cause mortality and perhaps cardiovascular death. There was no association with risk of cancer death. No clear associations were found for early age at combined natural and surgical menopause and any of the specific cancers examined, or cerebrovascular disease. There may be an association with CHD, but its evidence base was weak. Nested cohort of the RCGP OCS: Premature menopause was associated with decreased risk of: all-cause, cancer-, and circulatory-related mortality, all incident cancer, other cancers, and CHD. Premature menopause was not associated with: incident breast, main gynaecological, or colorectal cancer; all circulatory disease, cerebrovascular disease, or other circulatory disease. For early natural menopause, a significantly decreased risk was observed for: death from all causes, cancer, and non-cancer, non-circulatory causes; incident all cancer, colorectal cancer (borderline), other cancers; incident all circulatory disease and CHD. No significant risk was observed for circulatory mortality; incident breast or main gynaecological cancer; incident cerebrovascular disease or other circulatory disease. Compared with natural menopause, surgical menopause increased circulatory-related mortality only. The risk of incident main gynaecological cancers was decreased. The other incident cancer outcomes were not associated with surgical menopause. Risk of any, and each type of incident circulatory disease was not significantly altered with surgical menopause.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:571687 |
| Date | January 2012 |
| Creators | Pokoradi, Alida Jennifer |
| Publisher | University of Aberdeen |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=192389 |
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