Introduction to Table V Premature Deaths, Monthly Mortality, and Monthly Physician Contacts -- United States

MMWR 1982;31:109-10 (March 12, 1982)

Beginning with this issue, a new table will appear monthly in the MMWR: "Table_V. Potential Years of Life Lost, Deaths, and Death Rates, by Cause of Death, and Estimated Number of Physician Contacts, by Principal Diagnosis" [see page 18]. By displaying a variety of measures that gauge the importance and relative magnitude of certain public health issues, this table will call attention to those issues where strategies for prevention are needed. Publication of this table reflects CDC's increased responsibility for promoting action to reduce unnecessary morbidity and premature mortality and continues the MMWR's tradition of disseminating public health information to its readership.

Further improvements in health can be achieved through actions taken by individuals as well as by administrators in the public and private sectors to promote a safer and healthier environment (1). To this end, the new table provides information regarding areas that provide the greatest potential for health improvement.

Causes of death are listed in Table_V in descending order of the potential years of lost life that are attributed to each cause. In 1980, heart disease, cancer, and cerebrovascular disease account for 67.9% of all deaths in the United States; motor-vehicle and other accidents, suicide, and homicide accounted for 8.1% (2). In terms of age at the time of death, the relative importance of causes of death changes remarkably; motor-vehicle and other accidents, suicide, and homicide accounted for 40.8% of the total years of life lost prematurely (before age 65 years); and heart disease, cancer, and cerebrovascular disease accounted for 37.2%.

"Potential years of life lost before age 65" in the table is estimated for persons between 1 year and 65 years old at the time of death and is derived by multiplying the annual number of deaths in each age category by the difference between 65 years and the age at the mid-point of each category. If deaths of persons older than 65 years were included, greater weight would be given to natural causes of death, and premature and preventable causes of death would no longer be distinguishable. If deaths of persons younger than 1 year were included, causes of death affecting this age group would be weighted heavily and would therefore contribute a disproportionately large share of potential years of life lost. However, "Infant mortality" in the table is a measure of deaths occurring in this age group and "Prenatal care" reflects efforts to prevent death in this group.

Cause-specific mortality rates, published in the Monthly Vital Statistics Report by the National Center for Health Statistics, are estimated from a systematic sample of 10% of death certificates received in state vital statistics offices during a 1-month period using the underlying cause of death recorded on the certificate. Because complete information concerning the underlying cause of death is not available when the sample is taken, estimates for certain causes are biased in the monthly sample but then are corrected when annual estimates are made. The estimated number of deaths each month is obtained by multiplying the corresponding estimated mortality rate, which is computed on an annual basis, by the provisional population estimate for the United States and then dividing by the number of days for that month as a proportion of the total days in the year.

The measure for morbidity is obtained from the National Disease and Therapeutic Index (NDTI), a random sample of data from office-based physicians in 19 major specialities in the continental United States. Each physician in the sample records all his contacts with private patients for 2 consecutive days each quarter. These contacts comprise telephone calls (7% of total in 1981); office visits (68%); and patients visited by the physician in hospitals (22%), nursing homes (1%), and their own homes (1%). As a result, this measure gives greater weight to those diseases that prompt a visit to a private physician or required hospitalization. When the physician cannot make a diagnosis at the time of the visit, the suspected diagnosis or presenting symptom is recorded. Although misclassification might occur, the potential for this bias is reduced by using broad categories in the table.

Publication of Table_V is an effort to use measures of morbidity and mortality as reminders of the impact on public health of some of these preventable problems. However, when data are summarized, their complexity and detail are sacrificed; and when information is simplified, although the overall effect may be clarified, subtle issues may be obscured. Therefore, a series of articles exploring different aspects of preventable problems will be published in the MMWR to complement this table. These articles will present more detailed analysis of what is known about health status indicators, risk factors, and other factors affecting public health.

References

1. Healthy People, The Surgeon General's Report on Health Promotion and Disease Prevention, 1979. Public Health Service, Office of the Assistant Secretary for Health and Surgeon General, DHEW (PHS) Publication No. 79-55071.

2. National Center for Health Statistics. Monthly Vital Statistics Report, Vol. 29, No. 13, September 17, 1981.

Editorial Note -- 1997

Robert A Hahn, PhD, MPH, Division of Prevention Research and Analytic Methods (proposed), Epidemiology Program Office, CDC.

The 1982 addition to the MMWR of a monthly Table_V, "Premature Deaths, Monthly Mortality, and Monthly Physician Contacts -- United States," employed the measure of years of potential life lost (YPLL), which was designed to alert the public health community to the magnitude of "premature," "preventable," and "unnecessary" mortality. In contrast to the traditional measures of crude and age-adjusted mortality, which treats deaths at all ages equivalently, YPLL weights deaths inversely to age at death (i.e., deaths at young ages affect the value of YPLL more than deaths at older ages). Although the measure had been used since 1947 (1), the CDC series on YPLL especially raised awareness about the magnitude of the problem of injury among youth (2), causes of death among infants (e.g., sudden infant death syndrome [SIDS] and congenital anomalies [3,4]), and acquired immunodeficiency syndrome (AIDS) (5). YPLL contributed to the establishment of CDC's Violence Epidemiology Branch in 1983 and CDC's National Center for Injury Prevention and Control in 1992. Other measures of years of life lost have been modified to account for the "quality" of life lived with different types of morbidity and disability. For example, years of healthy life (YHL) considers activity limitations and perceived health and has been used to establish and monitor national health objectives in the United States for the year 2000 (6). In addition, disability-adjusted life years (DALY) "expresses years of life lost to pre-mature death and years lived with a disability of specified severity and duration" (7). Measures of YPLL have served primarily as tools for health-care planning, prioritization, and administration rather than as instruments of causal research.

An analysis of "potential years of life lost" was first published 50 years ago by Mary Dempsey (1), a statistician at the National Tuberculosis Association, who sought to indicate the relative youth of decedents from tuberculosis compared with cancer and heart disease; while crude mortality rates of the latter were far higher, YPLL rates were more comparable. Many modifications and alternatives to YPLL have been formulated (8,9). Dempsey used life-expectancy-at-birth cutoffs specific to the populations compared; in contrast, some have used a fixed life expectancy for all populations compared, as proposed by Haenszel (10). Others have used different age cutoffs, at both lower age limits (e.g., 0, 1, 15, and 20 years) and upper limits (e.g., 65, 70, 75, and 85 years). The measure including ages 15-70 years has been referred to as potentially productive years of life lost, on the assumption that these are the productive years of life (9). Another measure, years of accumulated ability lost (YAAL), weights the number of deaths by the age at which they occur, on the assumption -- contrary to that made in YPLL -- that the potential contribution of the decedent is greater with greater age and experience; YAAL may be regarded as the inverse of YPLL (11).

YPLL measures the burden of mortality among the relatively young. As a rate (generally calculated per population aged less than 65 years), YPLL could be compared by cause (e.g., injury, AIDS, and cancer) or etiologic agent (e.g., cigarette smoking, alcohol consumption, and automobiles), among populations (e.g., by sex, race/ethnicity, and state), and over time. Although YPLL rates may be age-adjusted, adjustment may mask differences in the public health burden of mortality among youth, which YPLL measures.

YPLL can be interpreted in at least two ways. First, as indicated by its name, YPLL may be regarded as the sum of years of life lost by persons who died before age 65 years; thus, for example, a person who died at age 24 years lost 41 years of life, assuming he or she would have lived to be only 65. Second, assuming that young persons have greater life expectancy than older persons and that death at young ages is therefore a greater loss than death at older ages, YPLL can be interpreted as a measure of mortality in which death at young ages is numerically weighted more heavily than death at older ages. For example, the death of a 5-year-old has a weight of 60 (i.e., 65 minus 5 years), 12 times the weight of 5 for a 60-year-old who dies (i.e., 65 minus 60 years).

The measure of YPLL reported in the MMWR has been modified in several ways over the course of its publication. Until 1986, deaths among infants (aged less than 1 year) were excluded from YPLL calculations in the MMWR because it was believed that they would "be weighted heavily and would therefore contribute a disproportionately large share of potential years of life lost" (12). In 1986, deaths during the first year of life were added to the calculation, and infant mortality was no longer reported separately in Table_V (13). This change resulted in the addition of congenital anomalies, prematurity, and SIDS as the fifth, sixth, and seventh causes of YPLL, respectively. Also beginning in 1986, YPLL tables and analyses were published annually rather than more frequently. In 1990 and 1992, annual MMWR reports on YPLL included comparison of YPLL with an upper age cutoff of 85 years in addition to the standard cutoff of 65 years (14,15). Initially, the nine leading causes of YPLL were reported; in the last years of publication, 13 leading causes were reported. While all-cause YPLL has declined slightly since the mid-1980s, this overall decline has been offset by an 11-fold increase in the proportion of YPLL associated with AIDS, first reported for 1984. In 1993, YPLL estimates based on provisional mortality data were not compared directly with estimates based on final data because of cause-specific differences in the delay of reporting provisional data (16). In 1986, a widely cited MMWR supplement, Pre-mature Mortality in the United States: Public Health Issues in the Use of Years of Potential Life Lost, was published to review alternative methods for the estimation of potential life lost (8).

The limitations of YPLL measures may constrain, in part, their usefulness. First, although YPLL has been thought to measure premature, preventable, and unnecessary morbidity and mortality, this assumption has not been evaluated and depends on the current state and deployment of knowledge and prevention strategies. Second, many YPLL measures ignore a large proportion of deaths in the population, including, for example, all deaths among persons aged greater than or equal to 65 years. In 1994, 73% of deaths in the United States occurred among persons aged greater than or equal to 65 years, and 24% occurred among persons aged greater than or equal to 85 years (17). Many measures neglect the potential for premature, preventable, and unnecessary morbidity and mortality among persons in these age groups.

An annual report on changes in YPLL was last published in MMWR in 1993 (16), although YPLL statistics have been routinely published in CDC's annual compendium Health, United States (18), and CDC programs continue to report condition- and etiology-specific YPLL in MMWR. CDC is reviewing its policy on how best to routinely disseminate age-related mortality information to achieve public health objectives. In addition to concerns about age-related value assumptions, there is growing interest in incorporating into summary health measures assessments of the "quality" of years lived or lost, the morbidity and disability associated with given causes of death before death, and self-perceived health status. These measures are intended to be used for surveillance and to provide a common denominator for cost-utility analysis. In addition, the importance of notions of premature, preventable, and unnecessary morbidity and mortality should be related to effective clinical and public health practice.

References

1. Dempsey M. Decline in tuberculosis: the death rate fails to tell the entire story. Am Rev TB 1947;56:157-64.

2. National Research Council. Injury in America: a continuing public health problem. Washington, DC: National Academy Press, 1985.

3. CDC. Premature mortality due to sudden infant death syndrome. MMWR 1986;35:169-70.

4. CDC. Premature mortality due to congenital anomalies. MMWR 1986;35:97-9.

5. Jaffe HW, Hardy AM, Morgan WM, Darrow WW. The acquired immunodeficiency syndrome in gay men. Ann Intern Med 1985;103:662-4.

6. Erickson P, Wilson R, Shannon I. Years of healthy life. Healthy People 2000 Statistical Notes 1995;7:1-14.

7. Murray CJL, Lopez AD. The global burden of disease: summary. Cambridge, Massachusetts: Harvard University Press, 1996.

8. CDC. Premature mortality in the United States: public health issues in the use of years of potential life lost. MMWR 1986;35(no. 2S).

9. Gardner JW, Sanborn JS. Years of potential life lost (YPLL): what does it measure? Epidemiology 1990;1:322-9.

10. Haenszel W. A standardized rate for mortality defined in units of lost years of life. Am J Public Health 1950;40:17-26.

11. Hahn RA. Years of accumulated ability lost (YAAL): a new measure for public health. Technology: Journal of the Franklin Institute 1995;332A:101-3.

12. CDC. Introduction to Table V: premature deaths, monthly mortality, and monthly physician contacts -- United States. MMWR 1982;31:109-10,117.

13. CDC. Changes in premature mortality -- United States, 1983-1984. MMWR 1986;35:29-31.

14. CDC. Years of potential life lost before ages 65 and 85 -- United States, 1987 and 1988. MMWR 1990;39:20-2.

15. CDC. Years of potential life lost before ages 65 and 85 -- United States, 1989-1990. MMWR 1992;41:313-5.

16. CDC. Years of potential life lost before age 65 -- United States, 1990-1991. MMWR 1993;42:251-3.

17. Singh GK, Mathews TJ, Clarke SC, et al. Annual summary of births, marriages, divorces, and deaths: United States, 1994. Monthly Vital Stats Report 1995;43:1-44.

18. CDC. Health, United States, 1995. Hyattsville, Maryland: US Department of Health and Human Services, Public Health Service, 1996; DHHS publication no. (PHS)96-1232.

Original report published with new editorial note in MMWR 1997:46:556-61 (June 20, 1997).

TABLE V. Potential years of life lost, deaths, and death rates, by cause of death, and
estimated number of physician contacts, by principal diagnosis, United States,
October 1981
====================================================================================================
                         Estimated annual         Estimated monthly
Cause of morbidity      total of potential           mortality (2)           Estimated number
 or mortality (Ninth    years lost before      ------------------------          of monthly
 Revision ICD, 1975)     age 65, 1980 (1)       Number     Rate/100,000    physician contacts (3)
-------------------------------------------------------------------------------------------------
ALL CAUSES (TOTAL)          10,006,060         164,950        844.4             96,550,000

Accidents                    2,684,850           8,500         43.5              5,156,000
 and adverse effects
 (E800-E807,
 E810-E825,
 E826-E949)

Malignant neoplasms          1,804,120          36,120        184.9              1,990,000
 (140-208)

Diseases of heart            1,636,510          61,810        316.4              5,168,000
 (390-398, 402,
 404-429)

Suicides, homicides          1,401,880           4,160         21.3                  --
 (E950-E978)

Chronic liver disease          301,070           2,730         14.0                100,000
 and cirrhosis (571)

Cerebrovascular                280,430          13,710         70.2                473,000
 diseases (430-438)

Pneumonia                      124,830           3,790         19.4                904,000
 and influenza
 (480-487)

Diabetes mellitus              117,340           3,130         16.0              2,764,000
 (250)

Chronic obstructive            110,530           4,280         21.9              1,824,000
 pulmonary diseases
 and allied
 conditions (490-496)
-------------------------------------------------------------------------------------------------
Prenatal care (4)                                                                2,187,000
Infant mortality (4)                             3,700         11.7/1000 live births
-------------------------------------------------------------------------------------------------
(1) National Center for Health Statistics. Monthly Vital Statistics Report, Vol. 29, No. 13, Septem-
ber 17, 1981. Total potential years of life lost are estimated for persons between 1 year and
65 years old at the time of death and are derived from the product of the number of deaths in
each age category and the difference between 65 years and the age at the mid-point of each
category.
(2) National Center for Health Statistics. Monthly Vital Statistics Report, Vol. 30, No. 11, Febru-
ary 10, 1982, pp 8-9. Infant deaths and provisional U.S. population from Vol. 30, No. 10, Janu-
ary 15, 1982, p 1. Mortality rates on an annual basis per 100,000 estimated population in the
United States are estimated from the underlying cause of death recorded on a 10% systematic
sample of death certificates taken from all those received in state vital statistics offices during
a 1-month period. The number of deaths each month is estimated from the product of the
corresponding estimated mortality rate and the provisional U.S. population estimated for that
month divided by the number of days that month as a proportion of the total days in the year.
(3) IMS America. National Disease and Therapeutic Index (NDTI), Monthly Report, October 1981,
Section III. This estimate comprises the number of office, hospital, and nursing home visits and
telephone calls prompted by each medical condition based on a stratified random sample of
office-based physicians (2100) who record all private patient contacts for 2 consecutive days
each quarter.
(4) "Prenatal care" and "infant mortality" are included in the table because "Potential years of
life lost" does not reflect deaths of children <1 year.="==================================================================================================="" 

Disclaimer   All MMWR HTML versions of articles are electronic conversions from ASCII text into HTML. This conversion may have resulted in character translation or format errors in the HTML version. Users should not rely on this HTML document, but are referred to the electronic PDF version and/or the original MMWR paper copy for the official text, figures, and tables. An original paper copy of this issue can be obtained from the Superintendent of Documents, U.S. Government Printing Office (GPO), Washington, DC 20402-9371; telephone: (202) 512-1800. Contact GPO for current prices.

Page converted: 04/20/99

HOME  |  ABOUT MMWR  |  MMWR SEARCH  |  DOWNLOADS  |  RSS |  CONTACT POLICY  |  DISCLAIMER  |  ACCESSIBILITY

Morbidity and Mortality Weekly Report Centers for Disease Control and Prevention 1600 Clifton Rd, MailStop E-90, Atlanta, GA 30333, U.S.A Department of Health and Human Services

This page last reviewed 5/2/01