A study in the journal Environmental Health Perspectives finds a correlation between the quality and characteristics of housing and the quality of health over time. The study found that nationwide changes in housing since 1970 were consistent with trends in health conditions such as asthma, lead poisoning, and hypertension over the same time period.
For example, the study found that asthma rates increased from 3.4% in 1972 to 7.8% in 2002. These increases occurred concurrently with the increased use of forced air furnaces and central air conditioning units, and the increased prevalence of broken and barred windows in homes. The study found that the use of forced air heating and air conditioning systems increased the presence of airborne particulate allergens in homes because the higher air velocity of these systems “re-suspends” dust particles that would otherwise settle out of the air. Similarly, the authors concluded that an increase in broken and barred windows increased the risk of asthma because they reduced the infiltration of fresh air in homes, which increased the exposure to household asthma triggers.
Cardiovascular health was linked to the changes in housing proximity to open space, commercial and industrial facilities, street noise, and neighborhood air quality. The study found that hypertension rates decreased over time, along with a decrease in street noise and bad smells in the neighborhood. The study attributed the decline in noise and bad smells to an increased use of zoning in urban areas that separated residential neighborhoods from industrial, manufacturing, and high traffic areas.
The study also found that blood lead levels in children younger than 13 years of age declined dramatically over the three-decade period, as older houses that were more likely to have lead paint were demolished or rehabilitated. In addition, housing improvements that reduced water leakages and interior moisture were found to have reduced exposure to lead by improving paint film durability. A reduction in childhood lead poisoning was found to be the one notable area in which progress in reducing the health and housing disparities of disadvantaged groups has been made. Other housing and health indicators showed national improvement over time but not necessarily a reduction in disparities between rich and poor.
The study combined data from the American Housing Survey and the National Health and Nutrition Examination Survey from the early 1970s to the early 2000s to identify housing trends that could be related to changes in health within the national population. It is one of the first studies to integrate both population health and housing quality retrospectively on a national level. The authors suggest that, given the connections between health and housing, future national studies integrate measures of health, housing, and communities instead of measuring them in separate surveys.
The study, The Relationship of Housing and Population Health: A 30-Year Retrospective Analysis, can be found at: http://www.ehponline.org/members/2008/0800086/0800086.pdf.