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In a nutshell
- When the Doomsday Clock moves closer to midnight, researchers found significant increases in suicide rates, Alzheimer’s disease mortality, and substance-related deaths across a 70-year span.
- The strongest correlations discovered were between Clock settings and deaths from substance use disorders (rs = -0.967) and alcohol use disorders (rs = -0.948).
- The study suggests the Doomsday Clock might function as an unexpected “social determinant of health” indicator, with potential applications for healthcare planning and public health initiatives.
BOSTON — For 75 years, the Doomsday Clock has served as humanity’s most recognizable warning system for existential threats. Now, an alarming study suggests its movements might track more than just our proximity to apocalypse—they may also predict patterns of death and disease across America.
Published in the Bulletin of the Atomic Scientists, researchers Samuel Justin Sinclair and David A. Silbersweig discovered something both fascinating and disturbing: when the symbolic Clock edges closer to midnight, specific patterns of mortality rise in lockstep.
In particular, suicide rates climb, Alzheimer’s deaths increase, and substance-related fatalities spike dramatically. It’s as though our collective body responds physiologically to the world’s growing dangers.
“During times of greater societal threat, there may also be corresponding variations in mortality and disease,” write the researchers. Their conclusion suggests something profound: the Doomsday Clock might function as an unexpected “social determinant of health”—a macro-level measurement reflecting how global risks translate into individual suffering.
The timing couldn’t be more relevant. In January 2024, the Clock remained at 90 seconds to midnight—the closest to symbolic doomsday in its history—reflecting growing nuclear tensions, climate crisis, and emerging technological hazards. Meanwhile, America faces what many call a mental health epidemic, with suicide rates up 36 percent since 2000.
These parallel crises, the research suggests, may not be coincidental but interconnected through complex pathways affecting how we live, die, and cope with existential dread.
Connecting the Doomsday Clock to U.S. health patterns
The Harvard researchers analyzed Doomsday Clock settings from 1947-2024 alongside mortality data from the CDC (1950-2019) and mental health statistics from the University of Washington (1990-2019). The patterns they uncovered tell a compelling story about collective health in the shadow of global threats.
When the Clock moved closer to midnight, suicide rates climbed significantly over a 70-year span, suggesting our collective anxiety might manifest in deeply personal tragedies. Similarly strong connections appeared with Alzheimer’s mortality between 1999 and 2019, potentially reflecting links between environmental threats the Clock tracks and neurological disease progression.
Most dramatically, deaths related to substance use showed extraordinarily strong correlations (exceeding -0.90) with Clock movements. As global threats intensified, fatal overdoses increased proportionally—perhaps reflecting desperate attempts to cope with a world perceived as increasingly dangerous.
Curiously, some diseases showed the opposite pattern. Cancer, HIV, and diabetes mortality increased when the Clock moved away from midnight (indicating lower existential risk). This counterintuitive finding might reflect how medical advances tackle controllable health threats during periods when external dangers seem less urgent.
‘Something no one has looked at before’
The implications extend beyond academic interest. If the Doomsday Clock correlates with specific mortality patterns, it could inform how health systems prepare for broader social threats. Conversely, tracking certain disease patterns might provide insight into the true impact of the existential dangers the Clock aims to measure.
“This study represents a first step, with the inherent limitations thereof, but it suggests a bridge between the fate of the world, our psychology, and our health,” says Sinclair, a founding member of Mass General Brigham, in a statement. “This may sound intuitive, but it’s something that no one has looked at before. We hope it opens the door to further discussion.”
As the researchers note, other macro-level indicators—like the Global Peace Index or even the World Happiness Index—might similarly function as unexpected health predictors when viewed through this lens.
The Doomsday Clock has long warned humanity about existential dangers before it’s too late. This research suggests its movements may also reflect immediate, measurable impacts on human health—showing that when we face greater collective risk, we also face greater personal suffering from specific causes.
Paper Summary
Methodology
Sinclair and Silbersweig used a straightforward but powerful methodology that relied entirely on publicly available data. First, they compiled Doomsday Clock ratings directly from the Bulletin of the Atomic Scientists website, covering all years from 1947 to 2024. The Clock has been reset 25 times since its inception, starting at seven minutes to midnight in 1947 and reaching its current position of 90 seconds to midnight in 2023 (maintained in 2024). For the mortality portion of their analysis, they obtained data from the US Centers for Disease Control and Prevention covering years 1950-2019, representing age-adjusted death rates per 100,000 people for various causes of death. For mental health analysis, they accessed prevalence data from the University of Washington’s Institute for Health Metrics and Evaluation’s Global Burden of Disease project for 1990-2019, which provided percentages of the population affected by various mental health conditions.
The researchers entered this data annually for all available years and conducted statistical analysis using SPSS (Statistical Package for the Social Sciences). They used Spearman rank-order correlations to identify relationships between the Doomsday Clock settings and various mortality and mental health indicators. To account for potential false positives across multiple tests, they applied a Bonferroni correction to adjust the threshold for statistical significance. This adjustment helped ensure that reported correlations were robust and not merely due to chance.
Results
The study identified several significant correlations between Doomsday Clock settings and mortality rates. For Alzheimer’s disease (1999-2019), researchers found a strong negative correlation (rs = -0.890), indicating that as Clock settings moved closer to midnight (higher risk), Alzheimer’s mortality increased. Similarly strong negative correlations appeared for suicide (rs = -0.659), unintentional injuries (rs = -0.692), and substance use disorders (rs = -0.842).
Conversely, positive correlations emerged between Clock settings and HIV mortality (rs = 0.863), malignant neoplasms (rs = 0.471), and diabetes mellitus (rs = 0.473), meaning that as Clock settings moved further from midnight (lower risk), these mortality rates increased. This counterintuitive finding might reflect medical advances over time that have reduced mortality from these conditions.
For mental health indicators, the researchers found a strong negative correlation between Clock settings and prevalence of substance use disorders (rs = -0.842) and a strong positive correlation with alcohol use disorders (rs = 0.702). Most dramatically, extremely strong negative correlations appeared between Clock settings and death rates from both alcohol use disorders (rs = -0.948) and substance use disorders (rs = -0.967). While no statistically significant correlations were observed for other mental health categories (including anxiety, bipolar disorder, and schizophrenia), there was a negative trend for depressive disorders (rs = -0.351) that approached significance.
Limitations
The researchers acknowledge several important limitations to their study. First, the sample sizes vary considerably across datasets, both within and between categories. Some indicators have data for only a small number of years (as few as 21 years for Alzheimer’s disease), making it unclear whether these correlations would generalize across longer time periods. Second, CDC mortality reporting frequency changed over the study period—data was reported only once per decade between 1950 and 1979, then annually thereafter until 2019—potentially affecting the analysis.
Another limitation involves changes in how the Doomsday Clock itself has been set over time. For the first 26 years, the Clock was set by Eugene Rabinowitz (the Bulletin’s top editor) based on his discussions with scientists and nuclear experts. After his death in 1973, the Bulletin’s Science and Security Board took over this responsibility, potentially introducing methodological differences. The researchers also note that the factors considered in setting the Clock have evolved over time, initially focusing exclusively on nuclear threats but later expanding to include climate change, disruptive technology, cyber risks, and general political volatility.
Discussion and Takeaways
The researchers interpret their findings as suggesting that the Doomsday Clock might function as an important macro-level indicator of social determinants of health. During periods of greater threat and danger (as reflected by Clock settings closer to midnight), specific patterns of mortality and mental health conditions emerge—particularly increases in Alzheimer’s disease, suicide, unintentional injuries, and substance use disorders.
The strong link between Clock settings and suicide rates over 70 years is particularly noteworthy, potentially reflecting collective distress during periods of perceived global risk. Similarly, the extremely strong correlations with substance-related mortality (exceeding -0.90) suggest the Doomsday Clock may be capturing societal factors that drive extreme substance use patterns.
The counterintuitive positive correlations with certain diseases (including cancers and HIV) might reflect either the natural decline in these conditions due to medical advances or potentially increased public health efforts to address controllable medical conditions during periods when other external threats seem less manageable.
The researchers suggest these findings have practical implications. Healthcare policymakers could potentially use Doomsday Clock changes to anticipate and prepare for specific patterns of mortality and disease. Conversely, public health indicators might provide additional context for setting the Doomsday Clock itself. The study also raises questions about whether other macro-level indicators (like the Global Peace Index or World Happiness Index) might similarly function as population health determinants.
Funding and Disclosures
The study was formally reviewed and exempted from full Institutional Review Board review since it used only publicly available, aggregated population-level data and involved no human subjects. In terms of disclosures, Dr. Samuel Justin Sinclair reported no conflicts of interest. Dr. David A. Silbersweig disclosed being a co-founder and Scientific Advisory Board chair for Ceretype Neuromedicine, though this relationship was unrelated to the current research.
Publication Information
The study “Apocalypse now? Mortality and mental health correlates of the Doomsday Clock” was authored by Samuel Justin Sinclair and David A. Silbersweig, both affiliated with Brigham and Women’s Hospital and Harvard Medical School. It was published in the Bulletin of the Atomic Scientists in February 2025 (DOI: https://doi.org/10.1080/00963402.2024.2439762). The Bulletin of the Atomic Scientists is published by Routledge (Taylor & Francis Group).
