Title: Background information

Context:
Chronic pain is among the most common, costly, and disabling chronic medical conditions in the U.S. In the U.S., approximately 100 million adults experience chronic pain, and pain is associated with  approximately 20% of ambulatory primary care and specialty visits. Since the late 1990s and early 2000s, the proportion of pain visits during which patients  received opioids has increased significantly, as have opioid-related morbidity, mortality, overdose death,  and SUD treatment admissions. Approximately one in five patients with non-cancer pain or pain related diagnoses is prescribed opioids in office-based settings. According to the CDC, sales of  prescription opioids U.S. quadrupled from 1999 and 2014. The absolute number of deaths associated  with use of opioids has increased four-fold since 2000, including by 14% from 2013 to 2014 alone.  Between 1999 and 2015, more than 183,000 people died from overdoses related to prescription  opioids. In one survey, approximately one-third of patients receiving OT for CNCP (or their family  members) indicated thinking that they were “addicted” to or “dependent” on the medication or used the  medication for “fun” or to “get high.” From 2000 through 2013, the rate of heroin overdose deaths  increased nearly four-fold. In the 2000s, the majority of people entering treatment for heroin use used  prescription opioids as their first opioid.

Question: How much has the absolute number of deaths associated with the use of opioids increased since 2000?

Answer: four-fold