Fewer failing hearts. As the 54-year-old National Heart, Lung, and Blood Institute’s Framingham Heart Study, operated by Boston University since 1971, begins recruiting its third generation, it continues to mine new results from the wealth of information gathered from the original participants and their children. A report released this week in the New England Journal of Medicine reveals that the risk of dying after a diagnosis of congestive heart failure has dropped by about a third since the 1950s, and that the incidence of heart failure among women has dropped by a third during the same period. Most of the drop in the rate of heart failure among women occurred in the 1970s, and the number of new cases leveled off after that.
Heart failure, affecting about 4.8 million people in the United States and leading to 287,200 deaths a year, is a condition in which a weakened heart cannot pump blood efficiently through the body. It results in shortness of breath, extreme fatigue, and ultimately death as the heart becomes progressively weaker. Since heart failure is generally seen in older people, it was previously assumed that the number of deaths from congestive heart failure would increase as the U.S. population ages.
The Framingham study included 10,317 people, 1,075 of whom developed heart failure. It followed participants from the 1950s through the 1990s and found that among those who developed heart failure, the number of men who died within a five-year period after onset dropped from 70 percent in the earlier period to 59 percent in the 1990s. For women, the five-year death rate dropped to 45 percent from 57 percent.
The authors attribute the improvement in survival rates to improved treatments, including medications such as ACE inhibitors and beta-blockers, and surgical procedures such as valve replacement, bypass surgery, and angioplasty.
The researchers attribute the differences in the findings between men and women to sex-related differences in the causes of heart failure. Women often develop heart failure as a result of high blood pressure, a condition that has been more often diagnosed and treated effectively in recent years. Men often develop heart failure after suffering a heart attack, and although more people are surviving heart attacks, the damage to their heart makes them more vulnerable to heart failure.
Despite the good news, the researchers warn that heart failure continues to be a serious problem, with 550,000 new cases reported in the United States each year and 50 percent of those reported dying within five years.
A matter of scale. You notice very different things about a landscape when you are looking at it from the window of an airplane, driving through it in a car, or walking. Similarly, geographers have noted that the same set of data looks very different statistically, depending on the scale at which it is analyzed.
Sucharita Gopal, a CAS associate professor of geography, and Eric Kolaczyk, a CAS assistant professor of mathematics and statistics, have teamed up to create a multiscale model that can be applied to more accurately analyze data, such as census results, and help communities and government leaders make better planning decisions.
The research team, which also included graduate student Junchang Ju (GRS’03) and Undergraduate Research Opportunities Program students Aaron LeValley (CAS’03) and Artem Buynevich (CAS’03), used Massachusetts census data from the years 1980, 1990, and 2000.
The researchers identified a set of hierarchically defined units based on successive aggregations in the census data — towns, counties, regional planning areas, and statewide. They examined population and income data from the censuses, taking into account the multiple levels of the hierarchy using MATLAB, Cartographic Data Visualizer, and ArcView software, which they adapted specifically for this purpose.
Their multiscale analysis of Massachusetts data shows that the eastern part of the state experienced significant changes in relative population among towns within counties between 1980 and 2000, while the western part of the state experienced less change. More change was experienced between 1990 and 2000 than between 1980 and 1990, perhaps, the researchers suggest, because of the fundamental restructuring of the state’s economy from manufacturing to service-based industries.
The research is supported by the National Science Foundation. A detailed description of the Massachusetts data analysis and of the research methodology can be found at http://www.geocities.com/censusma.
Briefs" is written by Joan Schwartz in the Office of the Provost. To read
more about BU research, visit http://www.bu.edu/research.