Prognostic value of patient-reported symptom interference in patients with late-stage lung cancer.
OBJECTIVE
Patient-reported outcomes (PROs) have been found to be significant predictors of clinical outcomes such as overall survival (OS), but the effect of demographic and clinical factors on the prognostic ability of PROs is less understood. Several PROs derived from the 12-item Short-Form Health Survey (SF-12) and M. D. Anderson Symptom Inventory (MDASI) were investigated for association with OS, with adjustments for other factors, including performance status.


METHODS
A retrospective analysis was performed on data from 90 patients with stage IV non-small cell lung cancer. Several baseline PROs were added to a base Cox proportional hazards model to examine the marginal significance and improvement in model fit attributable to the PRO: mean MDASI symptom interference level; mean MDASI symptom severity level for five selected symptoms; SF-12 physical and mental component summaries; and the SF-12 general health item. Bootstrap resampling was used to assess the robustness of the findings.


RESULTS
The MDASI mean interference level had a significant effect on OS (p = 0.007) when the model was not adjusted for interactions with other prognostic factors. Further exploration suggested the significance was due to an interaction with performance status (p = 0.001). The MDASI mean symptom severity level and the SF-12 physical component summary, mental component summary, and general health item did not have a significant effect on OS.


CONCLUSIONS
Symptom interference adds prognostic information for OS in advanced lung cancer patients with poor performance status, even when demographic and clinical prognostic factors are accounted for.
Department of Mathematics and Statistics, Kennesaw State University, Kennesaw, Georgia.
Bradley J
BJ
Barney
Xin Shelley
XS
Wang
Charles
C
Lu
Zhongxing
Z
Liao
Valen E
VE
Johnson
Charles S
CS
Cleeland
Tito R
TR
Mendoza
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung; D005260:Female; D006305:Health Status Indicators; D006306:Health Surveys; D006801:Humans; D053208:Kaplan-Meier Estimate; D008175:Lung Neoplasms / Q000628:therapy; D008297:Male; D008875:Middle Aged; D063868:Patient Outcome Assessment; D011379:Prognosis; D016016:Proportional Hazards Models; D011788:Quality of Life; D012189:Retrospective Studies; D057566:Self Report; D012720:Severity of Illness Index; D018434:Sickness Impact Profile; D011795:Surveys and Questionnaires; D063189:Symptom Assessment