Table 4.

The top 3 association rules generated for the second example patient.

Rank, rule, and item on the rule’s left-hand side				Interpretation of the item		Interventions linked to the item
Rank 1: The patient’s last diagnosis of acute COPDa exacerbation was from the past 81.4 days AND the patient had >2 EDb visits in the past 6 months AND the patient’s nebulizer medication prescriptions in the past year included >11 medications → the patient will probably have at least one severe COPD exacerbation in the following 12 months
	The patient’s last diagnosis of acute COPD exacerbation was from the past 81.4 days		Having a recent acute COPD exacerbation shows a need for better control of the disease.		Provide education on managing COPD and more frequent follow-ups Ensure use of appropriate COPD medications Consider influenza shot, pneumonia vaccination, or smoking cessation Assess the need for pulmonary rehabilitation or home care Ensure that the patient has a primary care provider or is referred to a specialist
	The patient had >2 ED visits in the past 6 months		Using the ED indicates poor control of conditions or a lack of access to primary, specialty, or home care.		Provide education on managing COPD and more frequent follow-ups Ensure use of appropriate COPD medications Consider influenza shot, pneumonia vaccination, or smoking cessation Assess the need for pulmonary rehabilitation or home care Ensure that the patient has a primary care provider or is referred to a specialist
	The patient’s nebulizer medication prescriptions in the past year included >11 medications		Using many medications for COPD with a nebulizer indicates an ineffective regimen, poor treatment adherence, or poor control of the disease. Using nebulizer medications could be a sign of having a mild exacerbation or more severe COPD.		Simplify COPD medications to once-a-day formulations or combination medications Address concerns for adverse interactions between medications Provide education on the correct use of COPD medications or inhalers Consider strategies to improve medication adherence such as providing reminders for taking medications in time Medication reconciliation review by a physician or a pharmacist
Rank 2: The patient’s maximum BMI in the past year was <22.81 AND the patient’s last ED visit related to COPD occurred no less than 27.2 days ago and no more than 94.3 days ago AND the patient’s average length of stay of an ED visit in the past year was between 0.03 and 0.29 day AND the patient had between 2 and 4 encounters related to acute COPD exacerbation or respiratory failure in the past year→ the patient will probably have at least one severe COPD exacerbation in the following 12 months
	The patient’s maximum BMI in the past year was <22.81		Having an unintentional weight loss can indicate comorbidities or other complications, such as malnutrition or metabolic syndrome.		Optimize nutritional status to address low BMI Provide dietary education and advise appropriate exercise
	The patient’s last ED visit related to COPD occurred no less than 27.2 days ago and no more than 94.3 days ago		Having a recent ED visit related to COPD shows a need for better control of the disease.		Provide education on managing COPD and more frequent follow-ups Ensure use of appropriate COPD medications Consider influenza shot, pneumonia vaccination, or smoking cessation Assess the need for pulmonary rehabilitation or home care Ensure that the patient has a primary care provider or is referred to a specialist
	The patient’s average length of stay of an ED visit in the past year was between 0.03 and 0.29 day		Using the ED indicates poor control of conditions or a lack of access to primary, specialty, or home care.		Provide education on managing COPD and more frequent follow-ups Ensure use of appropriate COPD medications Consider influenza shot, pneumonia vaccination, or smoking cessation Assess the need for pulmonary rehabilitation or home care Ensure that the patient has a primary care provider or is referred to a specialist
	The patient had between 2 and 4 encounters related to acute COPD exacerbation or respiratory failure in the past year		Frequently having acute COPD exacerbations or respiratory failures shows a need for better control of the disease.		Provide education on managing COPD and more frequent follow-ups Ensure use of appropriate COPD medications Consider influenza shot, pneumonia vaccination, or smoking cessation Assess the need for pulmonary rehabilitation or home care Ensure that the patient has a primary care provider or is referred to a specialist
Rank 3: The patient had between 3 and 5 ED visits in the past year AND the patient’s minimum SpO2 c in the past year was between 17% and 89.5% AND the patient’s maximum percentage of neutrophils in the past year was >76.5% AND the patient smoked >0.48 pack of cigarettes per day in the past year → the patient will probably have at least one severe COPD exacerbation in the following 12 months
		The patient had between 3 and 5 ED visits in the past year	Using the ED indicates poor control of conditions or a lack of access to primary, specialty, or home care.		Provide education on managing COPD and more frequent follow-ups Ensure use of appropriate COPD medications Consider influenza shot, pneumonia vaccination, or smoking cessation Assess the need for pulmonary rehabilitation or home care Ensure that the patient has a primary care provider or is referred to a specialist
	The patient’s minimum SpO2 in the past year was between 17% and 89.5%		Having a low SpO2 indicates worsening of symptoms or other complications such as hypoxemia.		Evaluate for cardiopulmonary causes of hypoxemia Consider nighttime oximetry or sleep study to evaluate for nighttime hypoxemia or sleep apnea Assess the need for home oxygen or nighttime noninvasive ventilation
	The patient’s maximum percentage of neutrophils in the past year was >76.5%		Having a large percentage of neutrophils can indicate infections or distress.		Evaluate the respiratory system, for example, using radiographic imaging Consider doing diagnostic tests such as viral panel, sputum culture, or procalcitonin Evaluate other potential morbidities such as cardiovascular disease with an electrocardiogram, echocardiography, or laboratory tests such as brain natriuretic peptide or D-dimer
	The patient smoked >0.48 pack of cigarettes per day in the past year		Smoking is a key risk factor for COPD complications.		Provide education on the health risks of smoking Suggest and provide support for smoking cessation

^aCOPD: chronic obstructive pulmonary disease.

^bED: emergency department.

^cS_PO₂: peripheral capillary oxygen saturation.