Poor physical health-related life quality linked to AAV mortality risk
Physical but not mental health at diagnosis found to be factor in prognosis
A worse physical health-related quality of life (HRQoL) at diagnosis was associated with a higher mortality risk among a group of ANCA-associated vasculitis (AAV) patients in Korea, according to a new report.
This risk was particularly noted in people with the AAV types microscopic polyangiitis, or MPA, and granulomatosis with polyangiitis, known as GPA.
Mental health-related quality of life, however, was not found to be significantly linked to mortality outcomes.
“Poor baseline physical functioning [is] associated with premature death in patients with MPA and GPA,” the researchers wrote. “HRQoL assessment during initial diagnosis may provide clinical insights for this population.”
The study, “Clinical association of health-related quality of life and mortality in an antineutrophil cytoplasmic antibody-associated vasculitis cohort,” was published in Seminars in Arthritis and Rheumatism.
Investigating possible risk factors for death in AAV
People with AAV, a group of autoimmune diseases that cause damage to the kidneys, lungs, nerves, and other organs, have a higher mortality risk than do their peers in the general population.
Numerous studies have investigated possible risk factors for death among AAV patients. Identified factors include older age, male sex, smoking history, kidney and lung involvement, and greater overall disease activity.
Patient-reported life quality is another factor that can possibly affect the prognosis and survival of those living with chronic diseases, such as AAV. Indeed, a worse quality of life has been associated with an elevated mortality risk in large studies of people with cardiovascular disease.
While it has been reported that ANCA-associated vasculitis patients experience a diminished health-related quality of life — noted simply as HRQoL — whether this affects mortality had not been investigated.
Now, scientists in Korea examined the relationship between life quality, mortality risk, and other clinical factors in a group of 189 AAV patients. The participants, 40% of whom were men, had a median age of 62.
Life quality was evaluated with the 36-Item Short Form Health Survey (SF-36), a standardized metric that’s widely used as a generic measure of life quality in various chronic diseases.
The SF-36 contains mental subscales, identified as MCS, and physical subscales noted as PCS. Scores on each range from 0-100, where a higher score indicates better life quality.
In this study, median SF-36 scores among the patients were 47.5 for PCS and 53.3 for MCS.
Scores for both life quality components were significantly correlated with indicators of greater disease activity and inflammation. No differences in life quality were observed between patients with different AAV types. Overall, participants with general manifestations had significantly lower PCS scores than did those with kidney issues.
Clinicians encouraged to evaluate patients’ health-related quality of life
Over a median follow-up of 38.2 months, or a little longer than three years, 21 patients (11%) died. According to the researchers, MCS and PCS scores were significantly lower in patients who died compared with those who did not.
However, in final analyses, only a lower PCS score was found to be a significant, independent predictor of mortality — meaning that it impacted survival regardless of its relationship to other clinical factors that could possibly be influential.
For every one-point decrease in PCS, or physical health, there was a 3% increased risk of death.
A decrease in patients’ physical functioning appears to be the most important [factor] in predicting the outcomes of patients with AAV.
No patients with the disease subtype eosinophilic granulomatosis with polyangiitis died, “consistent with its distinct clinical features and relatively benign prognosis,” the researchers wrote.
Among a subset of MPA and GPA patients — those with the two most common disease subtypes — the risk of death was more than three times higher among individuals with a PCS below 53.75 compared with those with higher scores.
“A decrease in patients’ physical functioning appears to be the most important [factor] in predicting the outcomes of patients with AAV,” the researchers wrote.
“Physical fitness, which is more objectively quantified, has a relatively higher relevance to patient outcomes than mental wellness,” they added.
Other clinical factors also differed significantly between patients who did or did not die during follow-up. Some, such as older age and higher disease activity scores, have already been identified as mortality risk factors. Still, final analyses found that, among these, only age was an independent predictor of mortality.
Overall, “our findings also suggest that physicians treating patients with AAV, particularly those with MPA and GPA, are encouraged to evaluate HRQoL … to determine patients that require greater clinical attention,” the researchers wrote.
“Early identification of this high-risk population for premature death … might benefit clinical practice, as it could ensure patient monitoring and improve clinical outcomes,” they added.
Noted study limitations include the small number of patients in the analysis of mortality and the relatively short-term follow-up.