Study Reveals Trends In U.S. Death Rate, Leading Causes Of Death Over 30 Years

Age-standardized death rates from all causes have decreased in theUnited States since the 1960s; however, the overall trend maskssubstantial variations in cause-specific rates and in the number ofdeaths occurring in different age groups from specific conditions,according to background information in the article. Understanding thesetrends and the relationship between the age-standardized death ratesand the actual number of deaths that occur could provide valuableinsight into the forces that shape the nation's health.

Ahmedin Jemal, D.V.M., Ph.D., of the American Cancer Society,Atlanta, and colleagues examined trends in death rates and number ofdeaths from the six leading causes in the United States and consideredthe relationship of these trends to disease prevention and health carein an aging population. The researchers analyzed vital statistics dataon death in the United States from 1970 to 2002 from each of the 6leading causes of death: heart disease, stroke, cancer, chronicobstructive pulmonary disease (COPD), accidents (i.e., related totransportation [motor vehicle, other land vehicles, and water, air, andspace] and not related to transportation [falls, fire, and accidentalpoisoning]), and diabetes mellitus.

The researchers found that the age-standardized death rate (per100,000 per year) from all causes combined decreased from 1,242 in 1970to 845 in 2002 (32 percent decrease). The largest percentage decreaseswere in death rates from stroke (63 percent), heart disease (52percent), and accidents (41 percent). The largest absolute decreases indeath rates were from heart disease (262 deaths per 100,000), stroke(96 deaths per 100,000), and accidents (26 deaths per 100,000).

The death rate from all types of cancer combined increasedbetween 1970 and 1990 and then decreased through 2002, yielding a netdecline of 2.7 percent. In contrast, death rates doubled from chronicobstructive pulmonary disease over the entire time interval andincreased by 45 percent from diabetes since 1987. Despite decreases inage-standardized death rates from 4 of the 6 leading causes of death,the absolute number of deaths from these conditions continues toincrease, although these deaths occur at older ages.

"� the number of deaths continues to increase because ofpopulation growth and aging. It is the number of individuals affectedby various conditions rather than the age-standardized rate thatinfluence the planning and allocation of preventive and medicalservices," the authors write.

"Several important insights are suggested by these temporaltrends in the death rates and number of deaths at various ages. First,the decrease in the age-standardized death rate for 4 of the 6 leadingcauses of death in the United States represents progress toward one ofthe fundamental goals of disease prevention by extending the number ofyears of potentially healthy life. This progress has been greater forcardiovascular disease and for accidental deaths than for cancer, yeteven for cancer the age-standardized death rate has been decreasing by1.1 percent per year since 1993. Less favorable developments are theslowing of the decline in age-standardized mortality rates from strokeand accidents since the early 1990s, and the increase in death ratesfrom COPD and diabetes."

"The reduction in the death rate from accidents from 1970through the early 1990s coincided with implementation of a 55 mph speedlimit during the first energy crisis in the 1970s and mandated use ofseat belts in most states beginning in 1984. The recent flattening ofthe accident mortality rate coincides with the relaxation of themaximum interstate speed limits since 1987. The biphasic [having twophases] trend in cancer mortality rates reflects both the impact of thetobacco epidemic on tobacco-related cancers through 1990, followed byreduction in cancer mortality through tobacco control and advances inearly detection, in treatment, or in both. The increase in COPD deathrates results largely from the long-term effects of tobacco smoking inan aging population, whereas the increase in diabetes mortality sincethe late 1980s reflects dramatic increases in obesity," the researcherswrite.

"A consequence of the large decrease in cardiovascular deathrates, combined with high-birth rates that immediately followed WorldWar II, is the growing importance of health and health care needs in anaging population. While improved detection and treatment for chronicdiseases has resulted in declining mortality rates, it has alsoincreased the prevalence of 'treated disease' and an associatedincrease in health care expenditures," the authors conclude.

(JAMA. 2005; 294:1255 - 1259. Available pre-embargo to the media at www.jamamedia.org.)

Editor's Note: The American Cancer Society funded the analysis, interpretation, compilation of cancer surveillance data.