In this national study of ambulatory veterans with heart failure and reduced systolic function, 87% of subjects were prescribed an ACE inhibitor or ARB, and 82% were prescribed a beta blocker. Moreover, an additional one-third to one-half of patients not receiving these drugs had explicit documentation in the chart of reasons why they were not prescribed. On multivariable analyses, older patients were significantly less likely to receive ACE inhibitors or ARBs and beta blockers, with a substantial drop in use starting in patients age 65–79 years for ACE inhibitors/ARBs and in patients age 80 years and older for beta blockers. These age differences in drug treatment were no longer statistically significant after accounting for reasons explicitly cited by clinicians for not prescribing these drugs. However, we are unable to determine the specific reasons cited for non-prescribing and the extent to which they had clinical merit.
Our most straightforward—and perhaps most important—finding is that across a wide range of ages the strong majority of veterans with heart failure received guideline-recommended medications. This finding is consistent with previous studies in the United States. In the inpatient setting, rates of guideline-recommended medication use are high, with three recent national reports finding that at hospital discharge 78-85% of patients received an ACE inhibitor or ARB and 83-89% a beta blocker.6–8
Data on heart failure care in outpatients come from a variety of settings and time frames, and show greater heterogeneity in rates of guideline adherence. Several studies have found ambulatory treatment rates of approximately 58-82% for ACE inhibitors and ARBs and approximately 43-86% for beta blockers.29–32
The relatively high rates of guideline-concordant prescribing that we observed are consistent with reports for other conditions from VA, which have in part been attributed to VA’s coordinated efforts to improve care quality, including extensive use of clinical reminders (although the type and nature of reminders, including for heart failure, varies between facilities).26,33
Our other main finding—that use of guideline-recommended medications for heart failure is lower in older patients—is consistent with previous research as well.6,11–15
In recent studies of prescribing at hospital discharge, older patients were approximately 6-10% less likely to receive ACE inhibitors or ARBs and 5-8% less likely to receive beta blockers.6–8
These differences were attenuated—but for the most part did not entirely disappear– after controlling for a extensive set of potential confounders. Fewer studies have focused on age differences in care in outpatient settings in the United States. However, a number of studies from Europe have found consistently lower use of ACE-inhibitors and beta blockers in older outpatients, although many of these studies have methodologic limitations and had limited ability to account for potential confounders.13,34–36
Our results suggest that interpreting age differences in prescribing requires nuance. In our study, older patients had meaningfully lower rates of ACE inhibitor/ARB and beta blocker use in both absolute and relative terms, and the frequency of chart-documented reasons for not prescribing these drugs did not vary between age groups. In addition, differences in the inflection point between the drug types—with usage rates for ACE inhibitors and ARBs substantially dropping starting at age 65–79 years, and for beta blockers starting at age 80 and older—suggest a complex relation between age and treatment decisions for different drugs, even for the same condition. After removing patients with reasons for non-treatment from the denominator, point estimates of effect size for different age groups were similar but the associations between age and use of these treatments were no longer significant. It is difficult to know whether these reasons truly account for the observed treatment differences by age, or whether the associations persisted but were undetectable due to limited sample size. The presence of a persistently significant age effect when considering only the 3 beta blockers types specifically recommended by guidelines argues for (but does not prove) the latter explanation.
The manner in which data on reasons for non-prescribing were collected makes it impossible to closely examine the distribution of these reasons and the extent to which they were clinically justifiable. However, results from other studies in the outpatient setting present a mixed picture of the clinical appropriateness of not prescribing guideline-recommended medications to older patients. In a VA-based study of an intervention to improve guideline-concordant care in heart failure, physicians commonly cited patients’ inability to tolerate therapy as the reason for not following guideline recommendations.37
In other studies, half of patients not prescribed beta blockers and two-thirds to nearly all patients not prescribed ACE inhibitors had an identifiable clinical contraindication to drug therapy.38,39
However, many of these clinical contraindications are relative, not absolute. Previous work has shown that most older adults, even those with relative contraindications, can tolerate these medications, yet that many clinicians cite concern over side effects to ACE inhibitors and beta blockers as major barriers to treatment.7,23,40–42
Moreover, other work suggests that clinical inertia, lack of understanding of guideline recommendations and doubts about their applicability, and difficulty accessing care are substantial barriers to more complete use of these drugs.23,41–43
Our study has several important limitations. The chart review process used only the most recent test result to assess LVEF, although this measure varies over time and often improves with treatment. Nonetheless, this method is consistent with other major studies of adherence to heart failure guidelines.6
In addition, it is unclear to what extent our findings generalize to other health care systems. However, our overall findings are consistent with those observed in other, non-VA studies. Moreover, the VA has served as a bellwether and model system for evaluating many quality issues with wide applicability.26,44
In summary, we found that there was a clinically important drop in prescribing rates in older age groups that was not explained by a wide variety of factors, but that these differences were more difficult to detect after accounting for reasons cited in the clinical chart for non-prescribing. Patients in the upper reaches of age are different from their younger counterparts, and unique considerations need to be evaluated in making treatment decisions for this vulnerable group. Nonetheless, given the major clinical benefits of ACE inhibitors and beta blockers for the treatment of systolic heart failure, reasons for not prescribing these drugs should be compelling and clearly documented, and further work is needed to determine whether the reasons clinicians cite for non-prescribing to older patients represent good clinical judgment or suboptimal care. This approach can account for the special circumstances of older patients while avoiding the clinical inertia, unjustified fears, and subtle ageism that can result in underuse of these valuable agents.