Background/Purpose: To assess the age-related differences in total shoulder arthroplasty (TSA) outcomes and utilization and associated time-trends.

Methods: Nationwide Inpatient Sample (NIS) from 1998-2010 was used to study the time-trends in TSA utilization and outcomes, overall and by age.  Age was categorized as <50, 50- 64, 65-79 and ³80.  Time trends in TSA utilization were compared using logistic regression or the Cochran Armitage test. 

Results: The overall TSA utilization increased from 2.96 in 1998 to 12.68/100,000 in 2010.  Compared to 1998-2000, significantly lower rates were noted in 2009-10 for: mortality, 0.2% vs. 0.1% (p=0.0041); discharge to an inpatient facility, 14.5% vs. 13.3% (p=0.039); and hospital stay >median, 51.2% vs. 29.4% (p<0.0001).  TSA utilization rates/100,000 by age groups, <50, 50-64, 65-79 and ³80 years were: 0.32, 4.62, 17.82 and 12.56 in 1998 (p<0.0001); and 0.65, 17.49, 75.27 and 49.05 in 2010 (p<0.0001) with increasing age-related difference over time (p<0.0001).  Across the age categories, there were significant differences in the proportion: discharged to inpatient facility, 3.2% vs. 4.2% vs. 14.7% vs. 36.5% in 1998 (p<0.0001) and 1.8% vs. 4.3% vs. 12.5% vs. 35.5% in 2010 (p<0.0001) and the proportion with hospital stay >median, 39.7% vs. 40.2% vs. 53% vs. 69% in 2008 (p<0.0001) and 17.2% vs. 20.6% vs. 28.7% vs. 50.7% in 2010 (p<0.0001).

Conclusion: In a nationally representative sample, we noted increasing age-related differences indicate a changing epidemiology of TSA.  Age-related differences in outcomes can guide us to focus on those with worst outcomes.