Relationship Between Minor Developmental Physical Anomalies and Delirium Among Geriatric Inpatients

The authors aimed to evaluate the relationships of minor physical anomalies (MPAs) of the head and limb with delirium among geriatric inpatients, in order to determine the potential of MPAs as markers of delirium's underlying neuropathogenesis.

In total, 311 consecutively admitted general medical inpatients without dementia, ages ≥60 years, were assessed with the Delirium Rating Scale-Revised-98, Delirium Frontal Index (DFI), and Waldrop Developmental Anomalies Tool instruments. Multivariate logistic regression and point-biserial correlations were used to analyze the relationships between delirium and MPAs.

Overall, 275 (88%) study participants were in the nondelirium group, and 36 (12%) were in the delirium group. Small head circumference was the most common MPA (22%), followed by curved fifth digit (7%). These two MPAs were significantly more frequent in the group with delirium (OR=2.31 and OR=5.25, respectively), as was presence of at least one MPA (OR=2.55). Multivariate models that controlled for age and medical burden revealed even stronger relationships between MPAs and delirium (head MPA, OR=2.62; hand MPA, OR=7.23; and any MPA, OR=3.38). MPA and DFI score were significantly correlated with delirium severity but not with each other. Small head circumference and curved fifth digit rarely co-occurred (8%) in the delirium group and had different patterns of correlation with delirium characteristics.

The association of limb and head MPAs with delirium suggests that early developmental aberrations can affect neurological structures related to consciousness that reduce the threshold for delirium during inpatient hospitalization in later life. Specific neurological pathways need further delineation, although frontal regions were not implicated.