Sex and death: are they related?

Findings from the Caerphilly cohort study

Study Team
George Davey Smith, _ Professor of Clinical Epidemiology,
Stephen Frankel, _Professor of Epidemiology and Public Health Medicine,
John Yarnell, _ Senior Lecturer

Department of Social Medicine, University of Bristol, Bristol, BS8 2PR, b
Department of Epidemiology and Public Health, Queen’s University of Belfast, Belfast BT12 6BJ
Correspondence to: Professor Davey Smith zetkin@bristol.ac.uk

Objective:

To examine the relation between frequency of orgasm and mortality.
Study design: Cohort study with a 10 year follow up.
Setting: The town of Caerphilly, South Wales, and five adjacent villages.
Subjects: 918 men aged 45-59 at time of recruitment between 1979 and 1983.
Main outcome measures: All deaths and deaths from coronary heart disease.

Result:

Mortality risk was 50% lower in the group with high orgasmic frequency than in the group with low orgasmic frequency, with evidence of a dose-response relation across the groups. Age adjusted odds ratio for all cause mortality was 2.0 for the group with low frequency of orgasm (95% confidence interval 1.1 to 3.5, test for trend P=0.02). With adjustment for risk factors this became 1.9 (1.0 to 3.4, test for trend P=0.04). Death from coronary heart disease and from other causes showed similar associations with frequency of orgasm, although the gradient was most marked for deaths from coronary heart disease. Analysed in terms of actual frequency of orgasm, the odds ratio for total mortality associated with an increase in 100 orgasms per year was 0.64 (0.44 to 0.95).

Conclusion: Sexual activity seems to have a protective effect on men’s health.

Key messages

* Sex and death are common variables in epidemiology, but the relation between them has been little studied

* In this cohort study, mortality risk was 50% lower in men with high frequency of orgasm than in men with low frequency of orgasm; there was evidence of a dose-response relation across the groups

* The question of causation is complex, as with all observational epidemiological findings; several explanations are possible, but the evidence for causation is as convincing here as in many areas where causation is assumed

* These findings contrast with the view common to many cultures that the pleasure of sexual intercourse may be secured at the cost of vigour and wellbeing

* If these findings are replicated, there are implications for health promotion programmes

Original Research Paper

Introduction

Even for a group not especially known for humour, the epidemiologist’s standard joke about “being broken down by age and sex” is rather tired. It is also conceptually colourless, for the non-epidemiologist takes more interest in sex as an activity than as a stratification variable. Sexual behaviour as an exposure has been little investigated, outside its capacity for transmitting communicable disease. Few data exist on the association between patterns of sexual behaviour and later mortality, despite sex and death—the joint obsessions of adolescence[1] [2]—being frequently linked in youthful interpretations of the human condition.[3] [4] [5] [6] One barrier to the study of frequency of sexual intercourse as an exposure may be that observational epidemiology tends to be conducted on middle aged and ageing populations by middle aged or ageing researchers. The fading imaginations of researchers—assumed to be shared by their subjects—renders the whole area apparently uninteresting. This is an instance of a more general phenomenon of epidemiologists studying what interests other epidemiologists, and not always being drawn to areas of more general public concern. There may be more exciting issues for the public than determining exactly how many servings of fruit and vegetables a day may confer enhanced health, or discovering that smoking is even worse for people than was once thought.

A few exceptions to the general epidemiological silence on the association between sexual behaviour and later mortality exist. In the Duke first longitudinal study of ageing, frequency of sexual intercourse was inversely associated with mortality in men, and enjoyment of intercourse was inversely related to mortality among women.[7] This finding is compatible with a perception that the quantity of sexual activity is of more importance to men, while a greater concern with quality is seen among women.[8] [9] In a Swedish study early cessation of sexual intercourse was found to be associated with an increased mortality risk among men over a 5 year follow up.[10] Sexual dissatisfaction was found to be a risk factor for myocardial infarction in a case-control study of women, with premature ejaculation and impotence in husbands being the major underlying factor.[11] From a different perspective, the assumption that Catholic priests and nuns are celibate renders another epidemiological design relevant here. A retrospective cohort analysis involving 10 026 priests in the United States revealed a marginally increased overall standardised mortality ratio of 103 (95% confidence interval 100 to 106), though mortality for arteriosclerotic heart disease was more substantially raised (118, 113 to 122). [12] Interestingly, mortality for cirrhosis of the liver was greatly increased, with a standardised mortality ratio of 147 (122 to 173). A study of nuns found opposite findings, with lower overall mortality than in the general population. [13] Low rates of smoking among the nuns was considered to be key in this case.

Unfortunately all of these studies have contained only limited data on potential confounding factors and could thus say little about whether the observed associations were causal. In view of the dearth of evidence on this question we have examined the association between sexual behaviour and mortality in a cohort of men for whom data on health related behaviours, existing coronary disease at baseline, social class, and physiological risk factors are available.

References

[1] Joyce J. A portrait of the artist as a young man. London: Cape, 1956.
[2] Cohen L. The favourite game. London: Secker and Warburg, 1963.
[3] SCUM Auxiliary. Con/text 119. On: Obscure independent classics, vol 6. Ipswich: Hamster Records, 1983.
[4] Easton Ellis B. American psycho. New York: Simon and Schuster, 1988.
[5] Acker K. Blood and guts in high school. New York: Random House, 1984.
[6] Purdy J. Color of darkness. New York: Random House, 1961.
[7] Palrnore EB. Predictors of the longevity difference: a 25-year follow-up. Gerontologist 1982;6:513-8.
[8] Solanas V. SCUM manifesto. London: Olympia Press: Pans, 1971.
[9] Greer G. The female eunuch. London: MacGibbon and Kee, 1968.
[10] Persson G. Five-year mortality in a 70-year old urban population in relation to psychiatric diagnosis, personality, sexuality and early parental death. Acta Psychiatr Scand 1981;64:244-53.
[11] Abramov LA. Sexual life and frigidity among women developing acute myocardial infarction. Psychosom Med 1976;38:418-25.
[12] Kaplan SD. Retrospective cohort mortality study of Roman Catholic priests. Prev Med 1988;17:335-343.
[13] Butler SM, Snowdon DA. Trends in mortality in older women: findings from the nun study. J Gerontol Ser B 1996;51:S201-8.

BMJ 1997;315:1641-1644 (20 December)
Original Paper