OBJECTIVES: To quantify lifetime functional disabilities, this study estimated the disability-free life expectancy (DFLE), quality-adjusted life expectancy (QALE), loss-of-DFLE, and loss-of- QALE in patients with non-small cell lung cancer (NSCLC).

METHODS: We interlinked national databases and applied a rolling-over algorithm to estimate the lifetime survival function for patients with NSCLC. Age-, sex-, and calendar year-matched referents were simulated from vital statistics. All the above calculations were carried out by using the R package iSQoL2. Using EuroQOL-5 Dimension (EQ-5D) and Barthel index (BI), we repeatedly measured the quality of life and functions of NSCLC patients who visited our hospital from 2011 to 2020. We categorized BI score ≤ 70 as in need of long-term care and constructed linear mixed models to estimate the utility values and ADL scores.

RESULTS: We collected 960 cases and 3088 measurements of quality of life. The proportions without disability in age < 65 and stage I-IIIa, age < 65 and stage IIIb-IV, age ≥ 65 and stage I-IIIa and age ≥ 65 and stage IIIb-IV were 97.3%, 89.3%, 94.8%,78.3%, respectively, corresponding to DFLE of 15.3, 2.4, 6.8, 1.2 years and losses-of-DFLE of 8.1, 20.7, 4.0, 8.6 years, respectively, indicating a stronger effect of late stage than old age. Compared with NSCLC patients at early stage, those with advanced stages suffered from poorer performance of almost all items except ‘eating’ and ’stool’ at time of diagnosis and seemed to persist later on. The DFLE seemed a close approximation to QALE, but the latter is smaller than the former because of discomfort and depression in cancer survivors.

CONCLUSIONS: Early diagnosis of NSCLC may decrease burden of long-term care.