• Feeling like a Grinch ? At least it won’t shorten your life | Fox News
    http://www.foxnews.com/health/2015/12/10/feeling-like-grinch-at-least-it-wont-shorten-your-life.html

    Previous studies have linked happiness to longevity but researchers now say there’s no such scientific connection. So while being sick makes you unhappy, just being grouchy isn’t enough to make you ill or shorten your life.

    The results are based on questionnaires from more than 715,000 British women aged 50 to 69 who were enrolled in a national breast cancer screening program in the late 1990s.

    The women were asked things like how often they felt happy and how healthy they were. Nearly 40 percent of the women said they were happy most of the time while 17 percent said they were unhappy. After a decade of tracking the women, 4 percent had died.

    Scientists found the death rate among unhappy women was the same as those who were happy. The research was published online Wednesday in the medical journal Lancet.

    • Étude accessible, ici

      Does happiness itself directly affect mortality?
      The prospective UK Million Women Study
      http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(15)01087-9/fulltext

      Summary
      Background
      Poor health can cause unhappiness and poor health increases mortality. Previous reports of reduced mortality associated with happiness could be due to the increased mortality of people who are unhappy because of their poor health. Also, unhappiness might be associated with lifestyle factors that can affect mortality. We aimed to establish whether, after allowing for the poor health and lifestyle of people who are unhappy, any robust evidence remains that happiness or related subjective measures of wellbeing directly reduce mortality.

      Methods
      The Million Women Study is a prospective study of UK women recruited between 1996 and 2001 and followed electronically for cause-specific mortality. 3 years after recruitment, the baseline questionnaire for the present report asked women to self-rate their health, happiness, stress, feelings of control, and whether they felt relaxed. The main analyses were of mortality before Jan 1, 2012, from all causes, from ischaemic heart disease, and from cancer in women who did not have heart disease, stroke, chronic obstructive lung disease, or cancer at the time they answered this baseline questionnaire. We used Cox regression, adjusted for baseline self-rated health and lifestyle factors, to calculate mortality rate ratios (RRs) comparing mortality in women who reported being unhappy (ie, happy sometimes, rarely, or never) with those who reported being happy most of the time.

      Findings
      Of 719 671 women in the main analyses (median age 59 years [IQR 55–63]), 39% (282 619) reported being happy most of the time, 44% (315 874) usually happy, and 17% (121 178) unhappy. During 10 years (SD 2) follow-up, 4% (31 531) of participants died. Self-rated poor health at baseline was strongly associated with unhappiness. But after adjustment for self-rated health, treatment for hypertension, diabetes, asthma, arthritis, depression, or anxiety, and several sociodemographic and lifestyle factors (including smoking, deprivation, and body-mass index), unhappiness was not associated with mortality from all causes (adjusted RR for unhappy vs happy most of the time 0·98, 95% CI 0·94–1·01), from ischaemic heart disease (0·97, 0·87–1·10), or from cancer (0·98, 0·93–1·02). Findings were similarly null for related measures such as stress or lack of control.

      Interpretation
      In 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.