Impact of self-rated osteoarthritis severity in an employed population: Cross-sectional analysis of data from the national health and wellness survey

BACKGROUND: Although osteoarthritis (OA) often affects older persons, it has a profound effect on individuals actively employed. Despite reports of reduced productivity among workers with OA, data are limited regarding the impact of OA among workers. The objective of this study was to evaluate the impact of self-rated OA severity on quality of life, healthcare resource utilization, productivity and costs in an employed population relative to employed individuals without OA. METHODS: This cross-sectional analysis used data derived from the 2009 National Health and Wellness Survey (NHWS). Multivariable analyses characterized outcomes and costs (direct medical costs and indirect) among workers (full-time, part-time, or self-employed) ≥ 20 years of age who were diagnosed with OA and who self-rated their OA severity as mild, moderate, or severe relative to workers without OA. Evaluated outcomes included productivity, assessed using the Work Productivity and Impairment (WPAI) scale; health-related quality of life, using the SF-12v2 Health Survey; and healthcare resource utilization. RESULTS: 4,876 workers reported being diagnosed with OA (45.0% mild, 45.9% moderate, and 9.1% severe); 34,896 workers comprised the non-OA comparator cohort. There was a greater proportion of females in the OA cohort (55.5% vs 45.6%; P < 0.0001) and more individuals in the 40-64 year and ≥ 65 year age ranges (P < 0.0001). As OA severity increased, workers reported more frequent pain, poorer quality of life, greater use of specific healthcare resources (hospitalizations) and reduced productivity. All outcomes indicated a significantly greater burden among workers with OA relative to those without OA (P < 0.0001). Estimated total annual costs per worker were $9,801 for mild OA, $14,761 for moderate OA, $22,111 for severe OA compared with $7,901 for workers without OA (P < 0.0001). CONCLUSIONS: Workers with OA were characterized by significant disease and economic burdens relative to workers without OA that substantially increased with greater self-rated OA severity. Greater levels of OA severity were associated with reductions in quality of life and productivity, and increases in healthcare resource utilization and costs.