Accuracy of a heart failure diagnosis in administrative registers

Abstract

Background: The incidence of heart failure is frequently reported using hospital discharge diagnoses. The specificity of a diagnosis has been shown to be high but the sensitivity of a reported diagnosis is unknown. Purpose: To study the accuracy of a heart failure diagnosis reported to the Danish National Patient Registers during routine clinical work. Methods: The patient population consisted of 3644 consecutive patients admitted to all departments in one hospital. Diagnoses reported to the National Patient Register were recorded. A study team evaluated each patient independently of routine care, performed an echocardiogram and evaluated whether clinical symptoms of heart failure were present. Heart failure was defined in accordance with current ESC guidelines as symptoms of heart failure and evidence of cardiac dysfunction. Results: A registered diagnosis of heart failure (n = 126) carried a specificity of 99% and a sensitivity of 29% for all patients. The positive predictive value was 81%, the negative predictive value 90%. Conclusion: The diagnosis of Heart Failure in the Danish National Registers is underreported, but very specific.

Sleep Apnea, the Risk of Developing Heart Failure, and Potential Benefits of Continuous Positive Airway Pressure (CPAP) Therapy

“…Likewise, 57% of the HF diagnoses were nonspecific, which limited us from making any assumptions as to the direct causal pathway between SA and HF. Positive predictive values of SA and HF diagnoses in the Danish National Patient Registry are high; however, sensitivities are lower, which could have led to an underestimation of our results because of type 2 errors 1, 18…”

“…The following diagnoses were included: hypertensive HF, cardiomyopathy, cardiac insufficiency, left‐sided HF, lung edema, and unspecified HF (Table S1). Two separate studies have validated the HF diagnosis in the Danish National Patient Registry and found positive predictive values of 84% (77.9% for first‐time HF) and 81%, respectively 17, 18…”

“…First, we altered the primary outcome definition to include both a HF diagnosis and a filled prescription of any dose of loop‐diuretics between 45 days before to 45 days after the HF diagnosis, as has been done previously 16, 18. Loop‐diuretics are considered first‐line symptomatic treatment; thus, this restricted HF outcome was to only include potential symptomatic patients with HF.…”

High validity of cardiomyopathy diagnoses in western Sweden (1989–2009)

“…Diagnostic codes for all hospital discharges are entered into the IPR with complete coverage from 1987 onwards. A validation of other major diagnoses in the IPR was performed by the National Board of Health and Welfare in 2011, confirming the high validity (up to 85–95%) of major cardiovascular diagnoses 22. The International Classification of Diseases (ICD) is used in all Swedish hospitals.…”

“…In addition, when analysing the 20 medical records with an HF diagnosis and without complementary diagnoses as described in Methods section, none represented a missed cardiomyopathy diagnosis at any time. However, in three cases, the ICD codes for cardiomyopathy were recorded in subsequent years, indicating that causation is necessary when interpreting results from the hospital discharge registry 20, 21, 22…”