Happiness and unhappiness have no direct effect on mortality
Authors: Philipe de Souto Barreto, Yves Rolland
Journal: The Lancet (2015)

What defines a good life? If in answering this question you included happiness in your list, you are not alone. Indeed, the pursuit and enjoyment of happiness is a common goal and desire in life for most people. Adults of all ages, including those in old age, frequently report the experience of happiness as a determinant of a good life.1King LA Scollon CN What makes a life good?.J Pers Soc Psychol. 1998; 75: 156-165Crossref PubMed Scopus (268) Google Scholar Since both happiness and health are crucial aspects of quality of life, medical work about the potential positive effects of happiness on a person's health and longevity is a growing area that has received increasing attention in the past decade. In The Lancet, Bette Liu and colleagues2Liu B Floud S Pirie K Green J Peto R Beral V for the Million Women Study CollaboratorsDoes happiness itself directly affect mortality? The prospective UK Million Women Study.Lancet. 2015; (published online Dec 9, 2015.)http://dx.doi.org/10.1016/S0140-6736(15)01087-9Google Scholar use data from a cohort of women in the UK Million Women Study, mean age 60 years, to examine whether happiness was associated with good health and with reduced mortality risk after an average follow-up of about 10 years. The strongest correlates of unhappiness were treatment for depression and anxiety (odds ratio [OR] 0·224 [99% group-specific CI 0·218–0·229]) and self-reported poor health (OR 0·298 [0·293–0·303]). In crude analyses of 719 671 women without chronic health disorders from the cohort, unhappiness was significantly associated with an increased risk of all-cause mortality (age-adjusted rate ratio [RR] 1·29, 95% CI 1·25–1·33). However, in multivariate regression models adjusted for age, personal characteristics, treatment for illnesses, and self-reported health (the key factor) there was no significant association (0·98, 0·94–1·01). Other researchers have found that hedonic wellbeing (ie, a viewpoint that defines wellbeing through experiences of pleasure vs displeasure and that can be roughly summarised as happiness)3Ryan RM Deci EL On happiness and human potentials: a review of research on hedonic and eudaimonic well-being.Annu Rev Psychol. 2001; 52: 141-166Crossref PubMed Scopus (5408) Google Scholar is not a good predictor of mortality in women, when baseline levels of health and health behaviours had been taken into account. A Japanese cohort study (n=88 175)4Shirai K Iso H Ohira T et al.Perceived level of life enjoyment and risks of cardiovascular disease incidence and mortality: the Japan public health center-based study.Circulation. 2009; 120: 956-963Crossref PubMed Scopus (62) Google Scholar showed that high levels of enjoyment in life appeared to protect against cardiovascular mortality in men but not in women aged 40–69 years. However, another study5Tindle HA Chang Y-F Kuller LH et al.Optimism, cynical hostility, and incident coronary heart disease and mortality in the Women's Health Initiative.Circulation. 2009; 120: 656-662Crossref PubMed Scopus (302) Google Scholar with 97 253 women from the USA aged 50–79 years showed that high levels of optimism were associated with reduced mortality risk. Reviews6Veenhoven R Healthy happiness: effects of happiness on physical health and the consequences for preventive health care.J Happiness Stud. 2008; 9: 449-469Crossref Scopus (371) Google Scholar, 7Diener E Chan MY Happy people live longer: subjective well-being contributes to health and longevity.Appl Psychol Health Well Being. 2011; 3: 1-43Crossref Scopus (1269) Google Scholar and a meta-analysis8Chida Y Steptoe A Positive psychological well-being and mortality: a quantitative review of prospective observational studies.Psychosom Med. 2008; 70: 741-756Crossref PubMed Scopus (922) Google Scholar on the associations between happiness (hedonic wellbeing, subjective wellbeing, or positive psychological wellbeing) and longevity support the notion that happy people live longer. Although most studies on this topic did not adjust their analyses for self-reported health, they suggest that the associations between happiness and longevity are strongest among healthy individuals. Liu and colleagues' main finding2Liu B Floud S Pirie K Green J Peto R Beral V for the Million Women Study CollaboratorsDoes happiness itself directly affect mortality? The prospective UK Million Women Study.Lancet. 2015; (published online Dec 9, 2015.)http://dx.doi.org/10.1016/S0140-6736(15)01087-9Google Scholar does not support this association, since no significant relation was shown between happiness and mortality risk within the subgroup of people reporting good or excellent health (indeed, Liu and colleagues' analysis of only people reporting excellent health2Liu B Floud S Pirie K Green J Peto R Beral V for the Million Women Study CollaboratorsDoes happiness itself directly affect mortality? The prospective UK Million Women Study.Lancet. 2015; (published online Dec 9, 2015.)http://dx.doi.org/10.1016/S0140-6736(15)01087-9Google Scholar showed all-cause mortality risk to be slightly higher in the unhappiest individuals compared with the happiest). The happiness–mortality association seems to be, to some extent, sex-specific, with higher positive effects reported in men than in women.9Koivumaa-Honkanen H Honkanen R Viinamäki H Heikkilä K Kaprio J Koskenvuo M Self-reported life satisfaction and 20-year mortality in healthy Finnish adults.Am J Epidemiol. 2000; 152: 983-991Crossref PubMed Scopus (307) Google Scholar Previous research10Pinquart M Sörensen S Gender differences in self-concept and psychological well-being in old age: a meta-analysis.J Gerontol B Psychol Sci Soc Sci. 2001; 56: 195-213Crossref PubMed Scopus (355) Google Scholar shows different profiles of psychological wellbeing according to sex; for instance, women's wellbeing would rely more on positive interpersonal relations than men's. Moreover, in older adults, the difference between men and women on reported wellbeing and happiness increases with advancing age.10Pinquart M Sörensen S Gender differences in self-concept and psychological well-being in old age: a meta-analysis.J Gerontol B Psychol Sci Soc Sci. 2001; 56: 195-213Crossref PubMed Scopus (355) Google Scholar Therefore, men and women probably define happiness differently, which might explain, at least partially, sex-specific differences for the associations between happiness and medical outcomes, including mortality. Further qualitative research that allows separate content analysis for men and women about happiness across different age ranges is needed to improve understanding of the complex concept of happiness. Although mortality is one of the most well documented outcomes in reports on happiness, happiness has also been shown to be associated with other medical disorders, particularly a reduced risk of both incident cardiovascular diseases11Davidson KW Mostofsky E Whang W Don't worry, be happy: positive affect and reduced 10-year incident coronary heart disease: the Canadian Nova Scotia Health Survey.Eur Heart J. 2010; 31: 1065-1070Crossref PubMed Scopus (227) Google Scholar and disability levels12Collins AL Goldman N Rodríguez G Is positive well-being protective of mobility limitations among older adults?.J Gerontol B Psychol Sci Soc Sci. 2008; 63: 321-327Crossref PubMed Scopus (52) Google Scholar (see Diener and Chan7Diener E Chan MY Happy people live longer: subjective well-being contributes to health and longevity.Appl Psychol Health Well Being. 2011; 3: 1-43Crossref Scopus (1269) Google Scholar for a review). Research about happiness of older adults should focus on medical outcomes other than mortality, particularly the incidence and prognostic value of disabling diseases and disability, the most important clinical issues faced by elderly populations. For example, an important gap exists in knowledge about the potential associations of happiness with the incidence of cognitive decline and dementia; indeed, happiness is associated with healthy lifestyles, such as exercise and abstinence from smoking,2Liu B Floud S Pirie K Green J Peto R Beral V for the Million Women Study CollaboratorsDoes happiness itself directly affect mortality? The prospective UK Million Women Study.Lancet. 2015; (published online Dec 9, 2015.)http://dx.doi.org/10.1016/S0140-6736(15)01087-9Google Scholar which, in turn, are protective factors against dementia. Therefore, it is plausible to suggest that happiness could be associated with a reduced risk of incident dementia. Moreover, further research from a lifecourse perspective is needed since happiness during critical periods of development, such as in childhood, could have important consequences on health in adulthood. Irrespective of caveats (eg, happiness being measured by a single-item questionnaire, no adjustment for physical function or functional ability, and no adjustment for major life events) and limitations (ie, studying only middle-aged women), Liu and colleagues' study2Liu B Floud S Pirie K Green J Peto R Beral V for the Million Women Study CollaboratorsDoes happiness itself directly affect mortality? The prospective UK Million Women Study.Lancet. 2015; (published online Dec 9, 2015.)http://dx.doi.org/10.1016/S0140-6736(15)01087-9Google Scholar provides extremely valuable and robust information about happiness, health, and mortality. Its robustness relies on the very large sample size—indeed, the largest population so far in happiness studies—and the well conducted analyses, which took into account several factors associated with both happiness and mortality risk. Epidemiological evidence on associations between happiness and medical outcomes has been accumulating over the past two decades. Randomised controlled trials are needed. Although a methodological challenge, interventions should be operationalised to examine the direct effects of happiness on health outcomes in both healthy and clinical (eg, people with depression) populations, particularly in old age; happiness interventions have already been operationalised in the research field.13Lyubomirsky S Dickerhoof R Boehm JK Sheldon KM Becoming happier takes both a will and a proper way: an experimental longitudinal intervention to boost well-being.Emotion. 2011; 11: 391-402Crossref PubMed Scopus (377) Google Scholar Such studies should be powered to allow comparisons to be made across age ranges and between men and women. Cross-cultural studies could also shed light on the generalisability of interventions to promote happiness. We declare no competing interests. Does happiness itself directly affect mortality? The prospective UK Million Women StudyIn middle-aged women, poor health can cause unhappiness. After allowing for this association and adjusting for potential confounders, happiness and related measures of wellbeing do not appear to have any direct effect on mortality. Full-Text PDF Open Access