A recent study and a separate data analysis among Medicare patients have shed light into the concerning opioid epidemic in the United States. Researchers found 51 percent of all opioid medications distributed across the nation each year are prescribed to adults with mental illness, according to a study by Dartmouth-Hitchcock and the University of Michigan.  

The number is shocking, since the the group represents only 16 percent of the adult population.

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Researchers looked at individuals with depression and anxiety and found the opioid use among those with mental illness persists across all key characteristics, including cancer status and different levels of self-reported pain.

Among the 38.6 million Americans diagnosed with mental illness, 18 percent are being prescribed opioids each year. Meanwhile, only five percent of adults without mental disorders are likely to use prescription opioids. Out of the 115 million opioid prescriptions that are written each year, 60 million are for adults with mental illness.

Matthew Davis, co-author of the study and assistant professor at the University of Michigan School of Nursing, told International Business Times the numbers in the study “surprised” researchers. He said individuals with mental disorders are at a higher risk for substance abuse, making them a “vulnerable population.”

“To some degree it was alarming because people with mental disorders have a higher risk of abusing opioids,” Davis said. “It’s definitely a population to look at more closely in the future.”

The study, which is based on national data, will be published in the Journal of the American Board of Family Medicine on July 6.

Opioid Use Among Those Elderly

Meanwhile, data analysis on Medicare patients shows an overwhelming number of individuals are readmitted to hospitals shortly after being hospitalized over opioid poisoning.

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Dexur, a platform which analyzes healthcare data, recently looked into opioid abuse hospitalizations and readmittance rates in the United States. The data show a startling fact: 42 percent of Medicare patients hospitalized for opioid poisoning are readmitted within 90 days.

“When these patients were hospitalized for opioids we looked at what happened to them,” Dexur CEO Nik Rao told IBT about the data analysis.

Dexur analyzed data from the Medicare database between January-June 2015. The readmittance rate among Medicare patients within 30 days was 27-29 percent, and much higher within 90 days.

“They could be coming back again for opioid abuse, or chronic pain issues,” Rao said. “Quite often they can be chronic patients and they could abuse opioids.”

Hospital visits due to opioid poisonings are expensive too, with each stay cost averaging about $10,000, and extra stays costing the system $2,500 a day. The costs continue to escalate as 42 percent of patients find themselves readmitted, research shows.

Medicare patients, who are 65-years-old or above, could be prescribed opioids for multiple reasons, including severe pain, chronic pain, cancer or due to surgeries.

Government data released this month shows the number of opioid-related inpatient stays at U.S. hospitals increased by 64 percent between 2005 and 2014, with those ages 25-44 mostly affected. In 13 states, including California, Washington, Texas, Oregon and Georgia, those 65 years and older were the most likely to face opioid-related hospitalizations.

Statistics: Opioids And Heroin Deaths

In the U.S., 92 people die from an opioid overdose everyday, according to the Centers for Disease Control and Prevention. Since 1999, the number of opioid-related overdose fatalities, which includes prescription opioids (like oxycodone, hydrocodone, and methadone) and heroin, has quadrupled. At the same time, the amount of prescription opioids sold in the U.S. nearly quadrupled since 1999.

The abuse of prescribed opioids could lead to the use of heroin. In Ohio alone, 2.3 million people were prescribed opioids last year, a number that makes up 20 percent of the state’s population. Last month, Ohio Attorney General Mike DeWine filed a lawsuit against five major pharmaceutical companies. DeWine said the companies misrepresented the risks of prescription opioids that led to a drug addiction epidemic in the state.