Gender differences in accessing cardiac surgery across England: a cross-sectional analysis of the Health Survey for England

Abstract

Objective: to examine gender differences in access to cardiac surgery in a nationally representative sample. Design: nationwide cross sectional household based survey (Health Survey for England). Setting: private households in England around 1993 and 1994. Subjects: 1708 subjects reporting a history of either doctor diagnosed angina or heart attack from a stratified random sample of 32 378 people aged 16 and above. Outcome measure: the proportion reporting having had cardiac surgery or on a waiting list. Results: 13.5% reported previous (n=206) or pending (n=25) cardiac surgery. Men were more likely than women to have had or to be waiting for cardiac surgery (19.1% of men versus 6.8% of women, χ² 54.7, P<0.001). This finding was consistent regardless of age group and across three regional areas. The unadjusted odds ratio for cardiac surgery for men versus women was 3.3 (95% CI 2.3, 4.5, P<0.001) and was only slightly attenuated to 2.8 (95% CI 1.9, 4.0, P<0.001), after adjustment for other factors. The gender difference remained even when analysis was restricted to subjects reporting a previous heart attack, and after statistical adjustment for disease severity. Conclusion: women are less likely than men to receive cardiac surgery across all age groups and regional areas. These results include private operations and adjust for individual behavioural data. Neither disease severity or co-morbidity explains these discrepancies. Further studies are required to determine why this inequality occurs and how it can be addressed.

Introduction

Heart disease is the commonest cause of death in women, as well as men, in the western world. However, studies from both the U.S. and the U.K. indicate that women are about half as likely to receive intervention and treatment services for ischaemic heart disease than men, even when disease severity and co-morbidity have been taken into account (Steingart et al., 1991; Petticrew et al., 1993). Some studies, however, fail to demonstrate these observations and it is possible that differences in study methodology may in part account for these discrepant findings (Kee, 1995).

Studies in the U.K. have been able to adjust for important confounders such as disease severity and co-morbidity, but unlike studies from the U.S., interpretation of U.K. based studies have been limited by three major limitations. The first is that most studies used local health service activity data which may not be generalisable to the country as a whole as local differences in service configuration may have a major impact on the degree of equity observed. Indeed some studies have found investigation and treatment rates to be 1.5 to 2 times greater in men than in women (Kee et al., 1993; Petticrew et al., 1993), whereas others have found no sex difference (Sullivan et al., 1994).

Further, as most of these studies have used National Health Service data, they have not taken private procedures into account. Men are more likely to have private health insurance than women (Office of Population Censuses and Surveys Social Survey Division, 1989), and this omission may have attenuated the true sex difference in revascularisation rates. Finally, none of these studies accounted for individual behavioural risk factors, such as smoking, which may influence the likelihood of receiving surgery.

The health survey for England overcomes these limitations. This is an individual based countrywide health and health service use survey of a representative sample of the English population, which collected data on both private as well as NHS interventions. We therefore examined the sex difference in disease and intervention rates in this study population.