Loss of Productivity-Adjusted Life-Years in Working-Age Australians Due to Knee Osteoarthritis: A Life-Table Modeling Approach.

Objective: Productivity-adjusted life-years (PALYs) offers a novel approach for quantifying the productivity burden of chronic conditions at the population level over the working lifespan. This study was undertaken to estimate the productivity burden of knee osteoarthritis (KOA) among working-age Australians, defined as lost PALYs and lost gross domestic product (GDP).

Methods: A static life-table model was constructed to simulate the experiences of working Australians (between the ages of 15-64 years) with KOA and those without KOA, with follow-up to 65 years (retirement age), a 1-year cycle length, and an annual discount rate of 5%. KOA prevalence data were obtained from the 2019 Global Burden of Diseases, Injuries, and Risk Factors study. Demographic and mortality data were sourced from the Australian Bureau of Statistics. Health utilities and productivity indices were derived from published sources. Population-level losses in years of life, quality-adjusted life-years (QALYs), and PALYs attributable to KOA were estimated by comparing estimates in the KOA cohort to the no KOA cohort.

Results: In 2019, a total of 913,539 working-age Australians were estimated to have KOA, with an overall prevalence of 5.5% (4.5% in men and 6.5% in women). By retirement age, KOA was associated with 39,602 excess deaths, 125,651 years of life lost, 1,938,059 QALYs lost, and 1,943,287 PALYs lost. The economic impact of lost productivity due to KOA amounted to 424 billion Australian dollars in lost GDP.

Conclusion: Our modeling demonstrates a significant economic burden of KOA among the working Australian population, with marked productivity loss. Our findings highlight the need for public health funding and scalable population-level strategies for effective KOA prevention and support to maintain productive working.