Cluster analysis of symptoms in pulmonary arterial hypertension: a pilot study

Pulmonary arterial hypertension (PAH) is characterized by elevated pulmonary artery pressures leading to right heart failure and death.

The aim of this study was to use cluster analysis to describe the symptom profile in PAH and differences in the health outcomes of health status, health-related quality of life (HRQoL) and psychological states in the cluster groups.

A cross-sectional descriptive design was used. A convenience sample completed a socio-demographic and clinical data form, a PAH Symptom Severity and Interference Scale, the Medical Outcomes Study Short Form (SF-36), the United States Cambridge Pulmonary Hypertension Outcome Review (US CAMPHOR) and the Short Form of the Profile of Mood States (POMS).

Of the 151participants, the mean age was 53.5 ± 15.1 with the majority female (n = 128, 85%). Fifty-eight (41%) were disabled and 67 (44%) were Functional Class IV. The most prevalent symptoms were shortness of breath with exertion (n = 149, 99%) and fatigue (n = 144, 93%). Three clusters emerged: Cluster 1 diffuse symptoms (n = 93), Cluster 2 severe cardiopulmonary symptoms (n = 32) and Cluster 3 moderate cardiopulmonary symptoms (n = 26). Overall, on the SF-36 the participants had poor general health, reduced physical function, role physical, vitality, and a low composite score for physical health. On the POMS the sample had limited vigor and increased fatigue. Cluster 2 Severe Cardiopulmonary Symptoms had worse SF-36, US CAMPHOR and POMS scores than the other cluster groups.

Patients with PAH are experiencing a constellation of symptoms that are interfering with their life and emerging clusters were present.