Happy older people live longer, according to researchers at Duke-NUS Medical School in Singapore. The authors of the study found that an increase in happiness is directly proportional with a reduction in mortality.
The study utilised data for 4,478 participants of a nationally-representative survey to look at the association between happiness, assessed in the year 2009, and subsequent likelihood of dying due to any cause, until 31 December 2015. The survey was focused on individuals’ aged 60 years and older living in Singapore.
Happiness was assessed by asking the survey participants how often in the past week they experienced the following: “I felt happy”, “I enjoyed life” and “I felt hope about the future”. Their responses were considered in two distinct ways; a “happiness score”, and a “binary happiness variable – Happy/Unhappy”. A wide range of demographics, lifestyle choices, health and social factors were accounted for in the analysis.
The researchers found that among happy older people, 15% passed away until 31 December 2015. In contrast, the corresponding proportion was higher, at 20%, among unhappy older people. Every increase of one point on the happiness score lowered the chance of dying due to any cause among participants by an additional 9%. The likelihood of dying due to any cause was 19% lower for happy older people. Further, the inverse association of happiness with mortality was consistently present among men and women, and among the young-old (aged 60-79 years) and the old-old (aged 75 years or older).
“The findings indicate that even small increments in happiness may be beneficial to older people’s longevity,” explained assistant professor Rahul Malhotra, head of research at Duke-NUS’ Centre for Ageing Research and Education and senior author of the paper.
“Therefore individual-level activities as well as government policies and programmes that maintain or improve happiness or psychological well-being may contribute to a longer life among older people.”
June May-Ling Lee, a co-author, added: “The consistency of the inverse association of happiness with mortality across age groups and gender is insightful – men and women, the young-old and the old-old, all are likely to benefit from an increase in happiness.”
Interest in the pursuit of happiness to improve the health of older people has been growing. While previous studies have linked happiness or positive emotions with a range of better health outcomes, the evidence on the effect of happiness on living longer has been inconclusive. Many of these studies do initially observe a greater extent of happiness to be associated with a lower likelihood of dying, but this link disappears once differences in demographic, lifestyle and health factors between those less and more happy are accounted for.
This is one of the few Asian studies to have assessed the association between happiness and mortality among older people, while accounting for several social factors, such as loneliness and social network, therefore extending the generalisability of the findings to non-Western populations.
Objective: Research on the role of positive affect, such as happiness, on health outcomes is burgeoning. Within this context, evidence for an inverse effect of happiness on mortality is inconclusive. Furthermore, few studies link happiness with mortality among older people, and in Asian populations. We examine the association between happiness and all-cause mortality among older people in Singapore.
Methods: Data for 4,478 Singaporeans aged ≥60 years enrolled in a nationally-representative longitudinal survey (three waves: 2009; 2011; 2015) were utilised. Happiness, at baseline, in 2009, was measured using three positively-worded items from the Centre for Epidemiological Studies Depression Scale, and considered in two distinct ways in the analyses—continuous (‘happiness score’ [0–6]) and binary (happy [score = 6]/unhappy). All-cause mortality, until 31 December 2015, was assessed primarily using administrative databases, supplemented by data from survey waves 2 and 3. Multivariable Cox regression models assessed the association of ‘happiness score’ and the ‘binary happiness variable’ (separate models for each) with all-cause mortality.
Results: The likelihood of all-cause mortality was lower by 9% (multivariable hazard ratio (HR) [95% confidence interval]: 0.91 [0.87–0.95]) for each unit increase in ‘happiness score’, and was 19% lower for happy, versus unhappy, older people (HR: 0.81 [0.68–0.97]).
Conclusions: Happiness is associated with reduced likelihood of all-cause mortality among older people in an Asian population, with the benefit observed even for incremental increases in happiness. Activities, policies and programs that maintain or improve happiness may be beneficial for a longer life among older people.
Choy-Lye Chei, June May-Ling, Lee Stefan Ma, Rahul Malhotra