We found ECV to be relatively common among our adults with moderate or severe asthma who lived in mostly low income inner-city neighborhoods. ECV was associated with an increased risk of both ED visits and hospitalization for asthma and for ED visits in general regardless of cause. We also found asthma-related quality of life was lower in the violence-exposed group. There was no effect modification by social support; but there was a small degree of effect modification by depressive symptoms on the relation between ECV and overall ED visits and AQOL.
This study adds to the findings of earlier studies which showed that ECV was associated with poorer health of children.2, 3, 18, 20, 21
We have found a similar relationship between ECV and asthmatic adults. Previous studies were generally cross-sectional and thus unable to evaluate the critical temporal relation between ECV and asthma,2, 3, 18-21
However, our longitudinal prospective analysis significantly strengthens these earlier findings. Additionally, our outcome measures are not self-report of symptoms,2, 3, 18-21
but rather ED visits and, even more significantly, hospitalizations. These findings, together with the lack of significant effect modification by depressive symptoms and social support, suggest this effect is not simply one related to an individual's subjective perception of stress, but rather a significant association between ECV and health status. The relationship of ECV with asthma hospitalizations is particularly disturbing as hospitalizations represent not only patient distress, but physician judgment that health is at risk. Our study suggests that the ECV-exposed group was, in fact, sicker. Additionally, because overall ED visits were increased and there was a trend toward increase in overall hospitalizations, our findings suggest that ECV is associated with far reaching health effects, beyond the single condition of asthma.
What this investigation does not answer is whether ECV directly affects asthma through the generation of psychosocial distress or it is a marker for conditions that exacerbate asthma. One possibility is that psychosocial stress that arises from living in concentrated disadvantage with exposure to violence directly
affects health through, for instance, immune or neuroendocrine mechanisms. Recently Marin et al showed that exposure to stress is associated with immune changes in children: higher levels of IL-4, IL-5 and IFN-γ, thus suggesting how stress could act on the immune system to affect health.38
On the other hand psychological stress could also act indirectly, affecting, for instance, diet and lifestyle.
The other possibility is that ECV, rather than triggering health effects, acts as a marker for environmental conditions in communities with concentrated disadvantage. These environmental conditions, such as increased exposure to pollutants including tobacco and vehicular exhaust, substandard housing, limited access to healthy foods, health care, other social services, and outdoor exercise,16, 17
may then have a deleterious effect on health. It is important to point out, however, that ECV could be both a trigger and a marker; these two mechanisms are not mutually exclusive, and unraveling them will be difficult. Regardless of the mechanism that connects ECV and poor health, one would predict that reversing concentrated disadvantage would improve health; either by reducing psychosocial stress, or by reducing adverse conditions associated with concentrated disadvantage or both.
Like all research, ours has limitations. The analysis is a secondary analysis from a larger study. However, it is not an ad hoc analysis; and it is one of very few using longitudinal prospective data. Our measure of ECV is self-report like most such measures.28, 29
It did not differentiate between indirect violence (observing violence, when one is not a victim) and direct violence (when one is a victim). The paper by Wright et al3
used the word “occurred” and we used the word “witnessed” to describe exposure to violence, a change that may limit comparison of the results.
Finally, while our study population may not be generalizable to all patient groups, this specific group had significant morbidity with baseline FEV1 averaging only 66% of predicted. Depressive symptoms were increased in this group consistent with the CES-D scores frequently seen in poor urban populations.37
The AQLQ mean scores were also lower than seen in other studies24, 39
but consistent with other similar socio-demographic groups.27, 40
MOS Social Support score was in the range of a multi-ethnic urban sample of post-partum women attending a community health center41
and lower than a group of ovarian cancer survivors.42
In summary, our study, the first to examine an asthma outcome in adults exposed to ECV, finds:
- ECV was relatively common among our mostly inner-city patients and similar to the prevalence of exposure reported in other studies.10
- Those exposed to violence had approximately twice the rate of a hospitalization or ED visit for asthma in the past year. This is consistent with the ECV-ED association previously reported in children.43, 44
- Younger adults are more likely to be exposed to violence and more likely to have an ED visit.
- Neither depressive symptoms nor lack of social support were effect modifiers of the ECV-asthma-related hospitalization or ED relationships.
These findings contribute to the growing body of information about the link between community characteristics and health, and in particular, the growing understanding of ECV as a psychological stressor which can affect health.5