The importance of musculoskeletal conditions in society necessarily increases with an aging population since the prevalence and impact increase with age. An aging population puts increased numbers of persons in the age range of greatest risk for onset and worsened severity. However, it is not only among the elderly, or persons age 65 or older, that the impacts of aging are felt. Because the prevalence of musculoskeletal conditions is substantial among those 45 to 64 years of age, the proportion of all cases of musculoskeletal disease in this age range increased by one-third over a 15-year time frame, from about 29% (21.8 million persons) in between 1996 and 1998 to about 38% (39.3 million persons) between 2009 and 2011. During the same time periods, the proportion of cases among the elderly increased by 13%, from about 22% (16.5 million persons) in the earlier three-year period to about 25% (25.1 million persons) in the later one. (Reference Table 10.1 PDF CSV and Table 10.1.1 PDF CSV) Because conditions that exist among persons age 45 to 64 are likely to last for a long time, the increased proportion of cases in this age range may lead to protracted high medical care costs in the years to come.
The relative importance of this age range in costs of care is already clear. Between 1996 and 1998 and 2009 and 2011, the proportion of all medical care costs experienced by persons with musculoskeletal conditions who are 45-64 increased by 40%, from about 30% of all such costs to 42%. The proportion of incremental musculoskeletal medical care costs among persons 45 to 64 years of age increased by an even more, 67%, rising from 28% in the 1996 to 1998 period to 47% between 2009 and 2011. (Reference Table 10.9 PDF CSV)