Why Do Drug Overdoses Spike During Winter? A Look at Cold Weather-Related Risk Factors

Winter ambulance

Winter cold and snow storms are in full swing. Research from 2020 published in the journal Epidemiology is once again relevant. Addicts are more likely to die from an opioid overdose during or just after cold weather, suggesting a need for more effective public health responses to addicts during the winter months.

The Findings

Researchers at Brown University’s School of Public Health conducted a study in which they analyzed overdose deaths in Rhode Island and Connecticut. The results? The study authors found that cold snaps during winter increased the risk of fatal overdoses by 25%. For the exact details, the study authors said, “Low average temperature over the 3 to 7 days prior to death were associated with higher odds of fatal opioid overdose. Relative to 11°C, an average temperature of 0°C over the 7 days prior to death was associated with a 30% higher odds of death.”

To arrive at that finding, the researchers looked at more than 3,000 opioid-related deaths in Connecticut and Rhode Island from 2014 to 2017. They analyzed the average temperature on the day of each death and the temperature on various days up to two weeks before the death. The researchers found that an average temperature of 32 degrees three to seven days before the death day was associated with a 25% increase in the risk for fatal overdoses compared to periods in which the average temperature was 52 degrees.

Depressed addict in winter

In short, the researchers found that addicts were more likely to suffer fatal overdoses on a particularly cold day or on a day that followed a string of particularly cold days. Conversely, when the researchers examined above-average warm temperatures during the summer months, they did not find a spike in overdose deaths.

It seems there is a direct relationship between cold weather and overdoses. This observational fact should compel families, policymakers, healthcare leaders, and city/state government leaders to take more decisive action to help addicts get clean.

Potential Risk Factors. Why are Addicts More Likely to Overdose During Cold Weather Spells?

The Brown University researchers found several reasons why there may be a connection between overdoses and cold weather. They include:

  • Addicts are more likely to use drugs alone during winter. Because it’s more difficult to get around during winter and the weather tends to keep people at home, addicts are more likely to be at home and alone when using drugs. When they don’t have other people around, they’re less likely to have someone else notice that they’re overdosing.
“One possibility is that opioid use and exposure to cold weather could combine to create a negative biological effect....”
  • Cold weather might make addicts less likely to notice the signs of an overdose until it is too late. Cold weather has a physiological effect that may reduce the addict’s awareness of the first signs of an overdose. According to the researchers, “One possibility is that opioid use and exposure to cold weather could combine to create a negative biological effect. Opioids are known to reduce breathing, and even without the effect of drugs, it is already harder to breathe in cold air. Some opioids also reduce the temperature at which the body starts to shiver, which makes it harder to regulate one’s body temperature.”
Overdose in winter
  • Due to inclement weather and poor road conditions, EMTs might take longer to respond to overdoses. Inclement weather can lead to longer response times for EMTs. Given that an overdosing addict has just minutes to live, traffic delays and poor road conditions can be the difference between life and death.
  • Addicts are more likely to be indoors and away from good Samaritans who might be able to help them. Similar to the first example, addicts are less likely to use drugs outside during winter, which means it’s less likely for a Good Samaritan to notice the addict is overdosing and call for help.

A Spike in Overdoses During Winter Means Addicts Need Help Now

It seems addicts are more at risk of dying from drug overdoses during winter. Lead study author Brandon Marshall spoke to the need for the community to step up and intervene with at-risk residents during winter. “It is well known that opioids induce respiratory depression, and that’s what causes a fatal overdose. However, there may be a host of other risk factors that contribute to opioid overdose deaths, which could be avenues for effective interventions. Regardless of what is causing the correlation between cold weather and fatal overdoses, our findings suggest that agencies and organizations should consider scaling up harm-reduction efforts after a period of cold weather.” Some of the harm reduction efforts Marshall encouraged include cold weather-triggered public health messages that remind community members to check on neighbors and loved ones.

Looking to the future, family members of addicts, public health officials, emergency responders, policymakers, and political leaders should be more mindful of the added risks and dangers that addicts face during cold weather, especially during long spells of cold weather for several days. Critically, family members of addicts must do everything they can to get their loved ones into treatment quickly, and they shouldn’t wait until their addicted loved one “comes around.” By then, it might be too late.


  • NIH. “Increased risk of opioid overdose death following cold weather: A case–crossover study.” National Institutes of Health, 2020. ncbi.nlm.nih.gov
  • Brown. “Cold weather increases the risk of fatal opioid overdoses, study finds.” Brown University, 2019. brown.edu


Editorial Staff