Identifying Behavioral Phenotypes in Chronic Illness: Self-Management of COPD and Comorbid Hypertension

To identify and characterize the constellation, or clusters, of self-management behaviors in patients with chronic obstructive pulmonary disease (COPD) and comorbid hypertension.

Cluster analysis (n = 204) was performed with standardized scores for medication adherence to COPD and hypertension medications, inhaler technique, and diet as well as self-reported information on physical activity, appointment keeping, smoking status, and yearly influenza vaccination for a total of eight variables. Classification and regression tree analysis (CART) was performed to further characterize the resulting clusters.

Patients were divided into three clusters based on eight self-management behaviors, which included 95 patients in cluster 1, 42 in cluster 2, and 67 in cluster 3. All behaviors except for inhaler technique differed significantly among the three clusters (P's<0.005). CART indicated physical activity was the first differentiating variable.

Patients with COPD and hypertensioncan be separated into those with adequate and inadequate adherence. The group with inadequate adherence can further be divided into those with poor adherence to medical behaviors compared to those with poor adherence to lifestyle behaviors.

Once validated in other populations, the identification of patient clusters using patient self-management behaviors could be used to inform interventions for patients with multimorbidity.