Study Looks at Importance of Documenting Functional Class for PAH Patients

by Phyllis Hanlon, Contributing Writer

People with WHO Group 1 PH (PAH, pulmonary arterial hypertension) often experience a delay before a definitive diagnosis is made. After diagnosis is confirmed, doctors look at how severe the disease is using a classification system – either from the New York Heart Association (NYHA) or one specifically modified by the World Health Organization (WHO) for pulmonary hypertension (PH). Taking into consideration shortness of breath, fatigue during activity and fainting spells, doctors assign the patient one of four functional classifications (FC): FC-I, II, III, IV. The higher the number, the more severe the disease with a generally poorer prognosis.

Comprehensive Health Insights Inc., a Humana company, conducted a study, sponsored by Actelion Pharmaceuticals, to see if there might be a connection between functional class and higher health care resource utilization (HCRU) – including hospital resources, physician resources and other services – and costs. Past studies have found that people with PAH spend more on health care compared to people who don’t have PAH, but this research has not looked at more detailed information such as the impact of functional classifications.  Incorporating a point-in-time measurement of FC in a claims-based study helps provide a more complete understanding of HCRU and costs for people with PAH.

Using the Humana Research administrative claims database, the researchers found 476 patients that met their study criteria.  Since FC was not included as part of the administrative claim, they used medication prior authorization forms and pulled information from the medical chart to obtain functional class. Altogether, 10 patients (2.1%) were FC-I; 106 (22.3%) were FC-II; 302 (63.5%) were FC-III; and 58 (12.2%) were FC-IV.

The authors pointed out that although research shows FC “…is an important predictor of future survival in PAH patients,” this key indicator was captured in less than 10 percent of patient medical charts.

More than half of the patients were treated with an endothelin receptor agonist (ERA). During the data analysis, this could have included ambrisentan (Letairis®) or bosentan (Tracleer®). More specifically as their initial treatment, 37.9% of patients in FC-IV were given an ERA, 54.7% of FC-II patients, and 55% of FC-III patients. Further, 26.7% of patients began taking a second medication (FC-IV patients within 74.1 days; FC-III patients within 119 days; and FC-II patients within 109.7 days).

The average monthly costs for prescription medication were $4,590 for all patients included in the analysis, with no significant difference between FC (all p >0.10).

HCRU is a broad term that includes different type of healthcare expenses, including hospital admissions for any medical reason, emergency department visits, and outpatient clinic visits. The authors found that patients in FC-IV used these services more than patients in the other functional classes. Specifically, FC-IV patients had significantly higher number of hospitalizations per month compared to FC-III (0.2 stays per person per month [pppm] vs. 0.1 stays pppm) and FC-II (0.2 stays pppm vs. 0.1 stays pppm) patients. FC-IV patients also stayed in the hospital for a significantly longer period of time. Patients in FC-IV experienced a higher number of emergency department visits per month compared to both FC-III and FC-II patients.

This high use of health care resources came with a large price tag. According to the authors, the median cost for patients in FC-II was $7,620 pppm; $8,287 pppm for patients in FC-III; and $10,006 pppm for patients in FC-IV.

Since this study was retrospective using observational data only from Humana patients, no definitive conclusions about the relationship between FC and HCRU and costs can be made from this research. Although Humana is a large national plan, these results may not be representative of everyone in the United States. Additionally, in this type of study information can be missing and coding errors can occur. This study still suggests that point-in-time measurement of FC is useful in better understanding average use of health care resources and costs, in addition to providing important information about the severity and progression of the disease.

Consistent with previous research, the authors found that all PAH patients in this study required many services. Despite being a rare disease, PAH still has a great impact both in physical and monetary costs.  The authors stated, “Newer PAH therapies, oral treprostinil, riociguat, and selexipag, not available during the study observation period, may slow disease progression and reduce the risk of hospitalization consistent with the guidelines’ goal to attain low risk status for PAH patients.”  They concluded that patients in FC-III and FC-IV could lower their risks of worsening disease if they “…were actively treated using treatment guidelines…” which could lead to improved functioning and quality of life and might lower health care costs. “Therefore, functional class documentation is an important tool for all stakeholders – health plans, providers, and patients – as part of a PAH patient’s management plan.”

Each PH patient is different. It is essential that you talk to your own doctor about what treatment options are best for you. For more information on finding a doctor or an accredited care center, visit


A study conducted using observational data from Humana patients looked at the relationship between functional class and use of health care resources and costs of care.

Functional class is determined after pulmonary arterial hypertension (PAH) has been definitively diagnosed.

The study found that the higher the functional class (and more severe the disease), the higher the costs of care and use of health care resources.

Documenting functional class in patient medical charts provides information about the severity and progression of the disease.

All PAH patients in the study required many services and resources.