What is the relationship between early outpatient follow-up after acute myocardial infarction (AMI) and use of evidence-based therapies?

Title: Association of Early Follow-Up After Acute Myocardial Infarction With Higher Rates of Medication
Date Posted: 3/10/2008
Author(s): Daugherty SL, Ho PM, Spertus JA, et al.
Citation: Arch Intern Med 2008;168:485-491.


Study Question: What is the relationship between early outpatient follow-up after acute myocardial infarction (AMI) and use of evidence-based therapies?

Methods: A total of 1,516 patients hospitalized with AMI participated in the multicenter Prospective Registry Evaluating Outcomes After Myocardial Infarction: Events and Recovery registry. Early follow-up was defined as patient-reported visits with a primary care physician or cardiologist within 1 month after discharge. The primary outcomes were use of aspirin, beta-blockers, angiotensin-converting enzyme inhibitors, and statins in eligible patients at 6 months. Multivariable analyses assessed the association between early follow-up and medication use at 6 months, adjusting for patient and clinical characteristics. Secondary analyses compared medication use at 6 months for patients receiving collaborative follow-up from a single provider versus those receiving follow-up from both provider types.

Results: Among the cohort, 34% reported no outpatient follow-up during the month following discharge. Rates of medication prescription among appropriate candidates were similar at hospital discharge for both follow-up groups. Compared with those not receiving early follow-up, those receiving early follow-up were more likely to be prescribed beta-blockers (80.1% vs. 71.3%; p = 0.001), aspirin (82.9% vs. 77.1%; p = 0.01), or statins (75.9% vs. 68.6%; p = 0.005) at 6 months. In multivariable analyses, a persistent relationship remained between early follow-up and beta-blocker use (risk ratio [RR], 1.08; 95% confidence interval [CI], 1.02-1.15). In secondary analyses, statin use was higher in patients receiving collaborative follow-up (RR, 1.11; 95% CI, 1.01-1.22).

Conclusions: Early outpatient follow-up and collaborative follow-up after AMI are associated with higher rates of evidence-based medication use. Although further studies should assess whether this relationship is causal, these results support current guideline recommendations for follow-up after AMI.

Perspective: This prospective observational study demonstrated a modest advantage of early follow-up post-MI, but which could infer a significant clinical outcome benefit. I suspect it underestimates the value of the cardiologist assessment and opportunity for referral to cardiac rehabilitation, smoking cessation, and education. Our experience is that early follow-up by a nurse practitioner can be effective as well. Melvyn Rubenfire, M.D., F.A.C.C.