Exacerbated by the potent painkiller fentanyl, the opioid crisis in Massachusetts continued to worsen in 2015, with more people dying of overdoses, according to the latest quarterly snapshot from the state Department of Public Health.

There were 1,379 confirmed opioid-related overdose deaths in Massachusetts last year, an 8 percent increase over the number of confirmed deaths in 2014 (1,282). More alarming still, the 2014 figure represents a 41 percent increase over the number of overdose deaths in 2013 (911).

Confirmed and estimated opioid deaths in Massachusetts in 2014 and 2015 (Department of Public Health)

Estimated rates of unintentional opioid-related overdose deaths (Department of Public Health)

The estimated rate of unintentional opioid-related overdose deaths increased to 22.6 per 100,000 residents in 2015, up from 20.1 in 2014 and 13.6 in 2013.

Further, estimates from the first three months of 2016 "suggest the opioid death rate is comparable to the first quarter of 2015," according to the DPH news release out Monday.

The report, for the first time, includes data on fentanyl, a synthetic opioid that's many times more powerful than heroin. DPH finds that more than 50 percent of last year's opioid-related overdose deaths had a positive screen for fentanyl.

That's a higher percentage than a previous analysis for WBUR on drug cocktails had found.

“The first-time inclusion of data on fentanyl allows us to have a more honest and transparent analysis of the rising trend of opioid-related deaths that have inundated the Commonwealth in recent years,” Secretary of Health and Human Services Marylou Sudders said in a statement.

Here are five other datapoints from the new report:

DPH uses predictive modeling techniques for cases not finalized by the medical examiner. DPH estimates that there will be an additional 63 to 85 opioid-related overdose deaths in 2014 and 118 to 179 deaths in 2015. That would bring the 2015 number to 1,526 deaths.

More than 1,000 of the confirmed opioid-related overdose deaths in 2015 were men. That follows a previous snapshot from the state that found three-quarters of deaths are men.

The report includes county-by-county and town-by-town overdose death information. The counties with the highest opioid death rates for the period of January 2013 to December 2015 are: Essex County on the North Shore, and Plymouth, Bristol, Barnstable and Dukes counties on the South Coast, Cape Cod and Martha's Vineyard.

According to a preliminary tally, Boston had 126 opioid-related overdose deaths in 2015. That's up from 103 in 2014 and double the city's total in 2012.

Statewide, DPH estimates that EMS administered the overdose reversal drug naloxone 12,982 times in 2015.

The report comes six weeks after Gov. Charlie Baker signed into law compromise legislation that seeks to alleviate the state's opioid epidemic.

The bill includes a seven-day limit on first-time opioid prescriptions, efforts to evaluate patients within 24 hours of an overdose and addiction screening for middle and high school students.