Analyzing data on nearly 26 million EMS calls in 2020, they found that OD-linked cardiac arrests reached a peak in May, when lockdowns began to really take hold across the United States. "Peak rates [for emergency ODs] in May 2020 were more than double the baseline from 2018 and 2019," the researchers reported Dec. 3 in the journal JAMA Psychiatry. For the year as a whole, these incidents have risen by 50% compared to rates in 2018-2019.