Prevalence of and factors associated with therapeutic failure-related hospitalizations in the elderly

Purpose: A therapeutic failure (TF) is defined as a failure to accomplish the goals of treatment attributable to inadequate therapy, a drug-drug interaction that results in a sub-therapeutic level for a drug, or medication non-adherence. There is limited literature focusing specifically on TF-related hospitalizations and the factors associated with these hospitalizations in older adults.  Importantly, there is a validated and reliable instrument called the Therapeutic Failure Questionnaire (TFQ) that can be used to measure TFs.  The purpose of this study was to evaluate the prevalence of and factors associated with TF-related hospitalizations in older adults in a university-based hospital setting. 

Methods: This investigation was a retrospective cohort study that included patients with a primary care physician from the University of Pittsburgh Medical Center (UPMC) Senior Care Institute admitted to any UPMC hospital between September 1, 2011 and December 1, 2011.  Chart abstracts of inpatient and outpatient records of eligible patients were screened for a TF by using the TFQ.  Covariate data were obtained and grouped into three categories: demographics, health status, and access to care.  Descriptive statistics and bivariate analyses using Fisher’s exact tests were conducted to assess the association between the covariates and the primary outcome (TF).

Results: Of the 93 hospitalizations screened, 57 met inclusion criteria, and 18% (10/57) of hospitalizations were due to possible/probable TFs, involving 14 medications. All therapeutic failures were classified as preventable.  On bivariate analyses, both congestive heart failure (p = .028) and dependency for medication management (p = .036) were significantly associated with TF occurrence.   Omission of therapy was the most common cause for a preventable TF-related hospitalization.

Conclusion: Therapeutic failures are a potentially preventable cause of hospitalization in the elderly population and are commonly caused by omission of therapy.