Drug side effects have led to increased ER visits in older Americans

Side effects from medication are causing more older Americans to visit emergency rooms and leading to more hospitalizations, according to an analysis of ER data from 2005-2006 and 2013-2014. And across all age groups, the drugs most often causing side effects that sent people to an ER were the same ones identified a decade ago —anticoagulants, antibiotics, diabetes agents, and opioid analgesics.

These were among the findings in a study that examined emergency department visits for adverse reactions to medicines in 2013 and 2014, compared with 2005 and 2006. The goal was to determine the characteristics of side effects that lead to ER visits in hopes of identifying outpatient prescribing patterns that could mitigate adverse events.

The analysis, which was funded by the federal government and published on Tuesday in the Journal of the American Medical Association, examined nearly 42,600 cases from the National Electronic Injury Surveillance System — Cooperative Adverse Drug Event Surveillance project, which is a public health surveillance system based on a nationally representative sample of US hospitals.

Interestingly, the prevalence of potentially inappropriate medication use in adults aged 65 and up remained high and the study authors suggested that the Beers criteria, a widely used guideline to improve safe prescribing, had “limited utility in identifying patient populations who are at highest risk for adverse drug events.”

The study authors, several of whom work for the Centers for Disease Control and Prevention, also noted that three drug classes — anticoagulants, diabetes and opioid analgesics — that were recently targeted by federal patient safety initiatives were also implicated in nearly 60 percent emergency room visits due to side effects experienced among older adults.

The study has a lot of interesting information, and here are some highlights:

An estimated four ER visits for adverse drug events occurred per 1,000 individuals annually. The rate of ER visits among older adults, aged 65 years and older, was 9.7 visits per 1,000 individuals compared with 3.1 visits per 1,000 individuals for those younger than 65 years.

An estimated 35 percent of ER visits for adverse drug events occurred among adults aged 65 years or older in 2013 and 2014 compared with nearly 26 percent in 2005 and 2006.

Even after accounting for prescribing frequency, the authors found that the rate of ER visits for adverse drug events per prescription was previously significantly higher for anticoagulants and diabetes medicines than for most other drugs.

Prescribing more medicine than needed or taking excess dosages was the most common type of adverse drug event. Medication errors were documented in 1 of 10 ER visits for adverse drug events and an estimated 27 percent of visits hospitalization.

The proportion of ER visits due to side effects involving anticoagulants rose during the last decade along with increased use. From 2009 to 2014, oral anticoagulant use increased by approximately 38 percent, whereas the proportion of ER visits for anticoagulants increased by 57 percent.

Among children, aged 5 years and younger, antibiotics were most commonly implicated as well as among older children and adolescents, aged 6 to 19 years old. Among older adults — aged 65 and older — anticoagulants, diabetes drugs, and opioid analgesics were implicated in approximately 60 percent of ER visits for adverse drug events.

Among older children and adolescents, antipsychotics were the second most commonly implicated type of drug in ER visits for adverse drug events. This occurred, the authors noted, as antipsychotic prescribing increased sharply during the last two decades. “Up to 75 percent of antipsychotic use in children and adolescents is estimated to be for off-label indications and there is evidence of low adherence to recommendations for safety monitoring,” they wrote.

Compared with 2005 and 2006, the rates of ER visits increased among older adults — 5.2 visits per 1,000 individuals in 2005 and 2006 versus 9.7 visits per 1,000 individuals in 2013- 2014 — and among adults aged 50 years to 64 years — 2.5 visits per 1,000 individuals in 2005 and 2006 versus 4.3 visits per 1,000 individuals in 2013 and 2014. The rates for other age groups were similar for both periods.

The most common drug products implicated in ER visits for adverse drug events varied by patient age. Among children and adolescents aged 19 years or younger, the 15 most common drug products implicated were involved in an estimated 50 visits, excluding unsupervised ingestions by children. Eight of the 15 most common drug products implicated among children and adolescents aged 19 years or younger were antibiotics, and two were neuropsychiatric agents.

Among children aged 5 years or younger, antibiotics alone were the most common drug class implicated in 56.4 percent of visits for adverse drug events. Among children and adolescents aged 6 to 19 years, antibiotics were implicated in 32 percent of visits. And four of the 15 most common drug products implicated in ER visits for adverse drug events among older adults were anticoagulants and five were diabetes drugs.