EvidenceAStrongGood randomized trials in people that agree, with no serious weaknesses. New studies are unlikely to change the answer.
Yes. Slower reaction time is linked to a modestly higher risk of dying, about 10 to 14% higher in pooled results. It describes groups of people and can't predict one person's fate.
Who it's for
Adults generally, especially older adults; it isn't a screening test for individuals.
What to expect
A modest rise in group risk, not a personal forecast.
Watch out for
Reaction time can't say why someone is at risk or when.
Slower reaction times go with a higher risk of death
Each dot is a pooled result with a line for its range; values above 1 mean higher risk of death.
← BetterWorse →
No difference
Simple reaction time, all deaths1.1 (1.07 to 1.13)Clear worsening
Choice reaction time, all deaths1.14 (1.09 to 1.2)Clear worsening
Simple reaction time, heart deaths1.19 (1.14 to 1.24)Clear worsening
1
risk of death vs. faster reaction, 1 = same
Slower reaction times go with a higher risk of death
A meta-analysis A study that pools the results of several earlier studies into one overall estimate. It is usually the strongest kind of evidence. pooled seven long-term studies of healthy adults aged 18 and over. Slower simple reaction time was linked to about a 10% higher relative risk How much more or less likely something is in one group than another, as a ratio. A big relative change can still be a small change for any one person. of death from any cause and a 19% higher risk of heart disease death. Slower choice reaction time (responding to one of several signals) was linked to a 14% higher risk of death from any cause, but not clearly to heart disease death1Meta-analysis · 2021Is simple reaction time or choice reaction time an indicator of all-cause mortality or CVD mortality?SRT may be a predictor of all-cause-mortality and CVD mortality, and CRT is significantly associated with an increased risk of all-cause mortality.Public Health. These figures compare groups, so one person's gain or loss depends on their starting risk.
A study following 1,196 men for up to 40 years found each 100 milliseconds of slower simple reaction time was linked to a 17% higher relative risk of death. Choice-type reaction time gave 14%5Observational study · 2005 · 1,196 peopleEvaluation of movement speed and reaction time as predictors of all-cause mortality in men.19) were associated with mortality after adjustments for age, neurological/psychiatric and neck/arm pain histories. Age-associated impairments in motor control systems but not the decision to move affects longevity.J Gerontol A Biol Sci Med Sci.
A study of 1,350 people followed from age 56 for 29 years (833 deaths) linked longer and more variable reaction times to higher risk of death from the major causes. Effects were similar in size to those for an IQ test7Observational study · 2018Reaction times match IQ for major causes of mortality: Evidence from a population based prospective cohort study.The association between intelligence with mortality from the major causes is also seen with reaction times. That effect sizes are of similar magnitude is suggestive of a common cause. It also implies that the association of cognitive ability with mortality is unlikely to be due to any social, cultural or educational…Intelligence. Another study of 898 people followed from age 56 to 70 found reaction time explained the link between IQ and death6Study · 2005 · 898 peopleReaction time explains IQ's association with death.This new field of cognitive epidemiology provides arguably the strongest evidence for the importance of psychological factors in physical health and human survival. Finding the mechanisms that relate psychometric intelligence to mortality might help in formulating effective interventions to reduce inequalities in…Psychol Sci.
Variability matters, too. A review of 22 studies found that greater trial-to-trial swings in reaction time were consistently linked to higher risk of cognitive decline and death2Systematic review · 2017A Systematic Review of Longitudinal Associations Between Reaction Time Intraindividual Variability and Age-Related Cognitive Decline or Impairment, Dementia, and Mortality.Increased IIV over time is associated with normal ageing. However, further increases in IIV over and above those found in normal ageing may be a risk factor for future cognitive impairment or mortality. Measures of IIV may, therefore, have considerable potential as a supplement to existing clinical assessment to aid…J Int Neuropsychol Soc. Among 790 adults aged 70+ followed for 17 years, more variable simple reaction time was strongly linked to death, while average reaction time was not4Observational study · 2014 · 790 peopleIntra-individual reaction time variability and all-cause mortality over 17 years: a community-based cohort study.intra-individual variability in simple reaction time appears to have a robust association with mortality over 17 years. Health professionals such as neuropsychologists may benefit in their detection of neuropathology by supplementing neuropsychiatric testing with the straightforward process of testing simple reaction…Age Ageing. In 861 older adults followed for 8 years, variability predicted death after adjusting for age, sex, thinking scores and heart risk, and average speed did not3Observational study · 2017 · 861 peopleIs intraindividual reaction time variability an independent cognitive predictor of mortality in old age? Findings from the Sydney Memory and Ageing Study.After excluding incident dementia cases, the association of IIVRT with mortality changed very little. Our findings suggest that greater IIVRT uniquely predicts shorter time to death and that lower global cognition and prodromal dementia in older individuals do not explain this relationship.PLoS One.
In small studies of sick groups, slower or altered reaction tests were linked to death in 94 people with cirrhosis8Observational study · 1999Clinical features and survivial of cirrhotic patients with subclinical cognitive alterations detected by the number connection test and computerized psychometric tests.3). Multivariate regression showed that Scan and Choice2 tests had prognostic value on survival, in addition to Child-Pugh classes in the first year of follow-up.Hepatology. Slower psychomotor speed was linked to death in 166 people with heart failure9Observational study · 2010Memory dysfunction, psychomotor slowing, and decreased executive function predict mortality in patients with heart failure and low ejection fraction.As hypothesized, lower LVEF and memory dysfunction predicted mortality. Poorer global cognitive score as determined by the MMSE, working memory, psychomotor speed, and executive function were also significant predictors. LVEF or systolic blood pressure had similar predictive values. Interventions are urgently needed…J Card Fail.
Key studies
Study
Who
What it found
Review of 7 studies, 20211Meta-analysis · 2021Is simple reaction time or choice reaction time an indicator of all-cause mortality or CVD mortality?SRT may be a predictor of all-cause-mortality and CVD mortality, and CRT is significantly associated with an increased risk of all-cause mortality.Public Health
Healthy adults 18+
Slower reaction time linked to 10 to 14% higher death risk
Study following people, 20055Observational study · 2005 · 1,196 peopleEvaluation of movement speed and reaction time as predictors of all-cause mortality in men.19) were associated with mortality after adjustments for age, neurological/psychiatric and neck/arm pain histories. Age-associated impairments in motor control systems but not the decision to move affects longevity.J Gerontol A Biol Sci Med Sci
1,196 men, up to 40 years
17% higher risk per 100 ms slower
Study following people, 20187Observational study · 2018Reaction times match IQ for major causes of mortality: Evidence from a population based prospective cohort study.The association between intelligence with mortality from the major causes is also seen with reaction times. That effect sizes are of similar magnitude is suggestive of a common cause. It also implies that the association of cognitive ability with mortality is unlikely to be due to any social, cultural or educational…Intelligence
1,350 people from age 56
Slower times linked to death from major causes
Review of 22 studies, 20172Systematic review · 2017A Systematic Review of Longitudinal Associations Between Reaction Time Intraindividual Variability and Age-Related Cognitive Decline or Impairment, Dementia, and Mortality.Increased IIV over time is associated with normal ageing. However, further increases in IIV over and above those found in normal ageing may be a risk factor for future cognitive impairment or mortality. Measures of IIV may, therefore, have considerable potential as a supplement to existing clinical assessment to aid…J Int Neuropsychol Soc
Middle-aged and older adults
Variable reaction time linked to decline and death
Study following people, 20144Observational study · 2014 · 790 peopleIntra-individual reaction time variability and all-cause mortality over 17 years: a community-based cohort study.intra-individual variability in simple reaction time appears to have a robust association with mortality over 17 years. Health professionals such as neuropsychologists may benefit in their detection of neuropathology by supplementing neuropsychiatric testing with the straightforward process of testing simple reaction…Age Ageing
About 790 adults 70+
Variability, not average speed, linked to death over 17 years
Safety
Reaction tests carry no known harm. A slow result is a statistical signal and not a diagnosis.
What we don't know
Whether slow reaction time causes early death or reflects general ageing of the body and brain. These studies observe people and can't settle that.
Whether training to speed up reaction time lowers the risk of death.
Written by AI from the studies listed, without review by a clinician, and graded with the GRADE method. It can be wrong, so check the studies it cites. Education, not medical advice.