White matter hyperintensities are associated with the severity of late-life somatoform disorders and executive functions

Abstract

Background: Medically unexplained symptoms are often seen in the elderly. Recently, correlations between medically unexplained symptoms and somatoform disorders (SDs) have been reported. The existence of many interactive psychiatric aetiologies is known among SDs. Late-life SDs might be influenced by some aetiological factors caused by ageing processes, such as structural changes in the brain and cognitive dysfunctions. Aims: Under such circumstances, we investigated the presence of subcortical white matter hyperintensities (WMHs), which increase with ageing, and hypothesized that subcortical WMHs are related to the disease severity of late-life SDs. Furthermore, we confirmed whether cognitive dysfunction influences this process. Methods: To evaluate these hypotheses, we examined patients with medically unexplained symptoms who met the criteria for undifferentiated somatoform disorder and divided the patients into three groups according to the degree of subcortical WMHs: grade 0, grade 1, and grade 2. The subcortical WMHs were rated using Fazekas grading. Differences in symptom severity and cognitive functions were compared among the three groups. Results: The grade 2 group had the severest symptoms. Furthermore, the grade 2 group had lower cognitive function scores than the other groups. Conclusions: The present study showed that the presence of subcortical WMHs in patients with late-life SDs was a predictor of disease severity. Moreover, cognitive dysfunction appeared to play a role in the advancement of disease severity.