Identifying adverse drug events in nursing homes in East Texas
Monica L. Tenhunen, DNP, RN, GNP-BC, ANP-C
Bonnie Smithers, MSN, RN, FNP-C
Barbara Tucker, PhD, RN, FNP-C
1209 Whispering Glen
Royse City, Texas 75189 monica.tenhunen@tamuc.edu
714-357-5454 (day/evening)
903-886-5729 (fax)
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Identifying adverse drug events in nursing homes in East Texas
Introduction
Nurses administer or oversee administration of medications prescribed by the provider in nursing homes. It is estimated that 45% of medication errors occur during the administration phase.
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Nurses and providers are also responsible for assessment, monitoring, and evaluation of nursing home residents following an ADE.
The purpose of this study was to identify the rate of adverse drug events (ADEs) and the percentage of these ADEs that caused harm in East Texas nursing homes. In 2012, there were 1.4 million nursing home residents in the United States, of which the majority (85%) were adults 65 years or older. This number will continue to increase as the baby boomer population ages.
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Approximately 48% of all nursing home residents take nine or more prescribed medications daily. Current research indicates that one of every five-medication doses administered results in an error; therefore, almost half of all nursing home residents are at risk for two or more medication errors daily.
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A staggering 1.9 million medication error-related ADEs are estimated to occur in nursing homes nation-wide each year.
4 Many of these ADEs lead to emergency department visits and hospitalization. Approximately 10-33% of older adult hospitalizations are due to ADEs. In addition, ADEs are a leading cause of death in many countries.
4, 7-9

Literature Review
The review of literature for this study focused on ADEs in nursing homes. Reported
3 studies also have been conducted in acute hospitals and assisted living facilities. These facilities were excluded due to significant differences from nursing homes in terms of population, nursing staff, regulations, etc.
A review of ADE occurrence indicated a range of 1.19 to 7.26 ADEs per 100 resident months. In North Carolina, where there is mandatory reporting of medication errors, 8.0-10.5% of medication errors caused an adverse drug event with harm.
1, 10-11 A study completed in Spain found that 60.2% of residents had at least one ADE, equating to 0.2 ADEs per resident.
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This study also showed that an increased number of medications for a resident increased the risk of
ADEs. Another study found 3.7 ADEs per resident.
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Studies reviewed had different methods of measuring ADEs and did not provide detailed characteristics of the nursing homes that may have influenced results.
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One study did not have these constraints. In 2008, Gurwitz et al. repeated their 2005 study. They found over 10.0 ADEs per 100 resident months, an increase from the 9.8
ADEs per 100 residents months found in 2005.
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Methods
The current study is a retrospective medical chart review completed in two nursing homes in East Texas. Each nursing home has at least 120 beds with primarily custodial and longterm care residents. Chart reviews were done on residents who consented to the study or whose

4 proxy consented to the study. Charts were reviewed for two months on each consenting resident.
Prior to data collection, the study was approved by a university institutional review board and administration at both facilities.
The Trigger Tool for Measuring Adverse Drug Events in the Nursing Home was used for chart reviews.
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This tool was developed by a multidisciplinary expert panel after an extensive literature review. It has been adopted by the Institute for Healthcare Improvement as a best practice tool to identify adverse drug events and to identify whether they caused harm. A study completed using the Trigger Tool indicated it was effective in identifying adverse drug events.
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A number on the Trigger Tool identified residents of the nursing homes. This was to ensure resident medical records were not duplicated. Data was entered on summary sheets then analyzed in aggregate.
Results/Discussion
A total of 58 residents’ charts were reviewed, 27 at the first facility and 31 at the second.
The number of medication doses, ADEs and the ADEs that caused harm were entered on the
Trigger Tool. Data from the Trigger Tool was entered on a monthly summary sheet for each facility. An adverse drug event was experienced by up to 22% of residents during one month of the study. The rate of ADEs per 100 resident months was determined based on the total number of medication doses given and the total number of ADEs (see Table 1).

Table 1 ADEs/100 Resident Months
Facility
Facility #1
Facility #1
Facility #2
Facility #2
Month
1
2
1
2
ADEs/100 resident months
7.41
48.15
34.62
27.59
Identification of the ADEs that caused harm and the category of the harm were entered
5 on the monthly summary sheets. The percentage of ADEs that caused harm was determined based on the total number of ADEs and the number that cased harm. Twenty-two percent of
ADEs for these residents caused harm. Harm was temporary and none required hospitalization.
The rate of ADEs identified in this study is higher than in previous studies done in nursing homes. This may be due to the small sample size, characteristics of the sample that were not studied, and/or other aspects of the nursing homes. The percentage of ADEs that caused harm was also higher than in previous research. Even with the higher percentage, residents did not have any permanent harm or require hospitalization from these ADEs.
Methods to potentially increase sample size would include active recruitment of residents and their families to increase participation. Researcher attendance at nursing home resident council and presence on the weekends to discuss with family members may also increase participation. This would add to the quality of the data and increase generalizability of the results.

The Trigger Tool relies heavily on laboratory results to identify ADEs and may not capture all adverse drug events. Continued studies testing the Trigger Tool and other methods of
6 identifying ADEs should be completed. This study adds to the limited evidence on ADEs in nursing homes. Further research needs to be completed in nursing homes in Texas and throughout the United States to attempt to identify the incidence of adverse drug events and methods of prevention.

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