A systematic review and meta-analysis has found a significant association between sexual abuse and a number of functional somatic syndromes (FSS).

A total of 23 studies met the inclusion criteria. Of these, 19 were case-control studies (2,778 subjects) and four were cohort studies (1,862 subjects). Seven studies restricted their investigation to abuse which had occurred during childhood, the remainder did not.

A significant association was found between a history of sexual abuse and functional GI disorders (OR 2.43; 5 studies), non-specific chronic pain (OR 2.20; 1 study), psychogenic seizures (OR 2.96; 3 studies) and chronic pelvic pain (OR 2.73; 10 studies). There was no significant association with fibromyalgia, obesity or headache. When analysis was restricted to those with a history of rape, a significant association was found with fibromyalgia, chronic pelvic pain and functional GI disorders.

The case-control studies compared individuals who had been given a diagnosis of FSS with a control group. Sexual abuse was identified retrospectively from either questionnaires or interviews.

Recall bias is a major problem with case-control studies. The largest of the four cohort studies (1,196 subjects) included in the review specifically investigated this problem.¹ A total of 676 children with documented child abuse or neglect and 520 matched controls were followed up into young adulthood. Medically unexplained pain symptoms were identified by diagnostic interview. No significant association was found between documented sexual abuse and unexplained pain symptoms, OR 1.39 (95% CI: 0.85-2.26). However, when sexual abuse was identified using retrospective self-reports, a significant association was found (OR 2.20), and it is this data which has been included in the systematic review. The authors of the original study suggest that the apparent link is an artefact of self-reporting.

Of the remaining cohort studies, two found no association and the other was only a short-term (two-year) follow-up of children and adolescents.

It has been suggested that childhood abuse does not increase the incidence of FSS but does increase the likelihood that those with FSS will seek healthcare. The apparent association may therefore be due to the fact that most of the included studies were from secondary care.

The authors recommend that we should routinely ask about sexual abuse in patients who have associated somatic syndromes. Disclosure itself may have a therapeutic benefit and patients may wish to be referred for cognitive therapy.

However, I think some caution is necessary here. The link has not been established by prospective cohort studies, and no trials have yet been carried out to determine whether abuse disclosure is beneficial in patients with FSS. There is a risk that disclosure, if it is not handled sensitively, may exacerbate feelings of shame and guilt.

It is better to avoid direct questioning: for selected patients e.g. those with multiple FSS, I have found that constructing a family tree with the patient offers them the opportunity to share information about childhood abuse, should they wish to do so.