The Lancet paper (1) reviews the evidence for a connection between child abuse and chronic pain in adults and finds some conflict in results. A prospective study of children whose maltreatment was confirmed by a court looked at rates of chronic pain when they reached age 29 compared with a group of matched controls and found no significant difference. On the other hand, retrospective studies of people with self-reported child maltreatment do show a significant increase in the rate of chronic pain.
Why this discrepancy? In the first study, it is possible that children whose abuse came to the attention of the judicial system were subsequently more protected from harm than other abuse survivors. A variation on this idea is that some of the matched controls in the first study were abused (but not subsequently protected by a court) so that the abused group and the control group ended up being fairly similar in their abuse burden. But the retrospective study also is subject to possible bias. First, the results imply that pain is not necessarily connected to how much abuse occurred, but how much was remembered. Second, there is evidence from other research that among adults with chronic pain, those mistreated as children seek medical care more often than those who were not abused even when pain levels are similar. Because research subjects are usually recruited from those who are seen in clinics, adult abuse survivors could be over-represented in research, making it look like abuse caused their pain. There is even more complexity to this issue that I will address in the next post.
1. Gilbert R et al. Burden and consequences of child maltreatment in high-income countries. Lancet 373, Issue 9657, 3 January 2009-9 January 2009, Pages 68-81.
Tags: childhood stress
