New research on older adults in the US finds that being unemployed, experiencing multiple job loss and even going for short periods without work is tied to a greater risk for heart attack (acute myocardial infarction, AMI) compared with no job loss. The researchers suggest people who suffer multiple job losses have a risk for heart attack that is on a par with smoking.

Matthew E. Dupre and colleagues from Duke University, Durham, North Carolina, write about their findings in the November 2012 online first issue of JAMA’s Archives of Internal Medicine.

There is lots of evidence that unemployment is a major source of strain, something that is affecting a growing number of adult Americans. However, there is little research on how the build up of multiple job loss and being out of work affects the risk of having a heart attack (AMI).

For their analysis, Dupre and colleagues looked at the links between aspects of unemployment and the risk for AMI in 13,451 adult Americans aged between 51 and 75 years who took part in the Health and Retirement Study, where participants underwent follow up interviews every two years between 1992 and 2010.

They found several aspects of past and present employment status raised the risk for a cardiovascular event, and:

“Although the risks for AMI were most significant in the first year after job loss, unemployment status, cumulative number of job losses and cumulative time unemployed were each independently associated with increased risk for AMI,” they write.

The median age of the group was 62, and over the whole follow up period the data covered 165,169 person-years of observation, during which 1,061 (7.9%) of the participants reported having a heart attack.

At the start of the study period, 14% of the participants were out of work, 69.7% had one or more cumulative job losses, and 35.1% reported having spent some time out of work.

Using statistical tools to calculate hazard ratios, the researchers worked out that risk for heart attack was a significant 35% higher among the unemployed compared to those who had not experienced job loss.

The more jobs people lost, the higher their risk for heart attack, the researchers found (22% for one job loss, rising to 63% for those who had lost four or more jobs).

And the risk of having a heart attack was “particularly elevated” during the first twelve months of unemployment (27% higher risk), but not after that, they write.

They also note that the higher risk for heart attack linked to multiple job loss is on a par with other more traditional risk factors, such as smoking, type 2 diabetes and high blood pressure.

The researchers call for further studies to look more closely at how work-related disparities in the population could be affecting risk for heart attack so as to identify targets for health initiatives.

They say this is especially important, given the current economic climate and the projected increases in job instability and unemployment in the US.

In an accompanying commentary, William T. Gallo of the City University of New York, says the study marks the start of a new era where we look more closely at how changes in socioeconomic factors like job loss affect heath.

“Sufficient evidence exists of the negative influence of job loss on health. The next generation of studies should identify reasonable pathways from job separation to illness so that nonoccupational interventions may be developed and targeted to the most vulnerable individuals,” he adds.

Written by Catharine Paddock PhD