1 table omitted
SOME PUBLIC health policy goals in the United States have been expressed as increases in the number of years of healthy life (YHL) (i.e., quality-adjusted life years), a measure of health that combines the effects of mortality with information about morbidity and disability.1 Data from national health surveys, in combination with life-table death rates and other information, have been used to calculate national estimates of the expected number of YHL at a given age.2,3 This report summarizes an analysis of data from the Behavioral Risk Factor Surveillance System (BRFSS) using these methods to estimate YHL for state populations during 1993-1995. The findings indicate substantial variability among the participating states.
The BRFSS is a continuous, state-based, random-digit-dialed telephone survey of the U.S. adult, noninstitutionalized population that measures the prevalence of health-risk behaviors and preventive health-care practices in the population.4-6 During 1993-1995, a total of 16 states* participating in BRFSS gathered the additional information required to estimate the expected YHL. Expected YHL was estimated using BRFSS interview data about limitations in activities of daily living and self-rated overall health status (categorized as excellent, very good, good, fair, or poor); preliminary, unofficial lifetable estimates for states for 1993; and national data about the institutionalized population. BRFSS estimates were weighted to provide representative estimates, and confidence intervals were computed using SUDAAN.
An index of health-related quality of life (HRQL) was computed.2 YHL was calculated by first computing the index of HRQL for each respondent (HRQL ranged from 1.0 [for those in excellent health and with no limitations] to 0.1 [for those who were limited in self-care activities of daily living and who were in poor health]). Second, the HRQL index was combined with lifetable functions to compute age-group specific expected YHL. This computation was based on multiplying the age-group specific lifetable number of total person-years lived by the average HRQL (range: 0.1-1.0) within each age group. The number of healthy person-years lived was summed for each age group and divided by the number of persons at each age. These data were adjusted using data from previous national estimates of the relative size and HRQL of institutionalized persons.2 Age-specific estimates of YHL represent the average number of YHL remaining to a person at a given age.
When averaged over all ages, state-specific estimates of HRQL ranged from 0.79 to 0.85. In most states, HRQL was higher for men (range: 0.79-0.87 across states) than for women (0.79-0.85).
The estimated YHL at age 25 years was 39-44 years and at age 65 years was 11-14 years. YHL was higher for women: at age 25 years, YHL was 41-47 years for women compared with 38-43 years for men; at age 65 years, YHL was 12-16 years for women and 10-13 years for men. State-specific HRQL varied directly with life expectancy. For example, expectation of life at age 25 years is correlated with average HRQL index (r=0.77, p <0.001).
J Cook, MBA, Alabama; B Bender, Arizona; M Leff, MSPH, Colorado; N Costello, MPA, Indiana; M Perry, Kansas; K Asher, Kentucky; R Meriwether, MD, Louisiana; H McGee, MPH, Michigan; T Murayi, PhD, Missouri; P Smith, Montana; S Huffman, Nebraska; K Zaso, MPH, New Hampshire; TA Melnik, DrPH, New York; J Grant-Worley, MS, Oregon; L Redman, Virginia; M Futa, MA, Wyoming. S Bland, MS, TRW, Inc, Atlanta. Behavioral Surveillance Br, Div of Adult and Community Health, National Center for Chronic Disease Prevention and Health Promotion; Mortality Statistics Br, Div of Vital Statistics, National Center for Health Statistics, CDC.
One of the national health objectives for 2000 is to increase the expectation of healthy life at age 65 years from 12 to 14 years (objective 17.1c).1 The findings in this report indicate that, among the 16 states assessed, only one (Montana) had achieved that level during 1993-1995. State and local public health programs need local data to evaluate and guide their prevention efforts, especially because of jurisdiction-specific differences in health, demographic, and socioeconomic conditions. In addition, many states independently establish health objectives similar to the national objectives. The analysis described in this report demonstrates the feasibility of developing state-specific estimates for HRQL and expected YHL and indicates state-specific variations in these indicators.
The methods used in this analysis are subject to at least two limitations. First, in addition to survey data on health and disabilities, the methodology requires lifetable data specific for the populations covered. The use of age-specific rates requires that many computations be based on small numbers of observation, thereby limiting the ability to calculate estimates for population subgroups. Potential alternative approaches would not depend on age-specific data (e.g., multivariate individual-level analysis of the determinants of HRQL or components). Second, the same nationally based correction for the institutionalized population was used for all states and subgroups; however, rates for institutionalization and health status of the institutionalized vary among states and subgroups. Despite these limitations, the state estimates are in the same range as the national estimates of YHL.2 Consistency of estimates between years for those states that collected the data for >1 year (Kansas, Nebraska, and New York) and the association between HRQL and mortality levels also support the quality of the estimates.
Years of Healthy Life—Selected States, United States, 1993-1995. JAMA. 1998;279(9):649. doi:10.1001/jama.279.9.649-JWR0304-3-1