The health of older adults declines over time, but there are many ways of measuring health. We examined whether all measures declined at the same rate, or whether some aspects of health were less sensitive to aging than others.
We compared the decline in 13 measures of physical, mental, and functional health from the Cardiovascular Health Study: hospitalization, bed days, cognition, extremity strength, feelings about life as a whole, satisfaction with the purpose of life, self-rated health, depression, digit symbol substitution test, grip strength, ADLs, IADLs, and gait speed. Each measure was standardized against self-rated health. We compared the 5-year change to see which of the 13 measures declined the fastest and the slowest.
The 5-year change in standardized health varied from a decline of 12 points (out of 100) for hospitalization to a decline of 17 points for gait speed. In most comparisons, standardized health from hospitalization and bed days declined the least while health measured by ADLs, IADLs, and gait speed declined the most. These rankings were independent of age, sex, mortality patterns, and the method of standardization.
All of the health variables declined, on average, with advancing age, but at significantly different rates. Standardized measures of mental health, cognition, quality of life and hospital utilization did not decline as fast as gait speed, ADLs, and IADLs. Public health interventions to address problems with gait speed, ADLs, and IADLs may help older adults to remain healthier in all dimensions.
Diehr, Paula H.; Thielke, Stephen M.; Newman, Anne B.; Hirsch, Calvin H.; and Tracy, Russell, "Decline in Health for Older Adults: 5-Year Change in 13 Key Measures of Standardized Health" (October 2012). UW Biostatistics Working Paper Series. Working Paper 385.