The opioid crisis claimed more lives in Massachusetts last year than initially estimated and shows no sign of abating this year, despite additional treatment programs and safeguards to prevent the abuse of prescription painkillers.

The state Department of Public Health said Tuesday that 1,256 Massachusetts residents died in 2014 after overdosing on opioids such as heroin and painkillers, according to a final tally of death records.

That toll is higher than the initial estimate of 1,008 opioid-related deaths that the department released in April. It also represents a 15 percent increase from 2013 and a startling 57 percent increase from 2012.

In the first three of months of this year, opioid overdoses claimed 312 lives in Massachusetts, putting the state on pace to match last year’s death toll.