Constipation Linked to Aggression in Nursing Home Residents

ST. LOUIS PARK, Minn., June 30 - Constipation can trigger physical aggression in a nursing home resident with dementia, researchers here reported.

In a large group of residents with dementia, those with constipation were about as likely to exhibit aggressive physical behavior as those who experienced hallucinations, said Ralph Leonard, M.D., M.P.H., of the medical software company CALM-MD here.

"To our knowledge no prior studies have investigated the association of constipation," Dr. Leonard and colleagues said in the June 26 issue of Archives of Internal Medicine. "We chose to study constipation a priori because it is common, modifiable, and recognized by clinicians to be a cause of many non-specific symptoms."

The cross-sectional study also confirmed results of previous studies that depression, delusions, and hallucinations were linked with aggressive behavior in nursing home residents with dementia, the authors said.

Dr. Leonard and colleagues examined records of more than 100,000 nursing home residents living in California, New York, Ohio, Pennsylvania, and Texas during 2002. All participants were 60 or older and had dementia. Data were obtained from the Minimum Data Set, a health assessment that must be completed for all residents of facilities that receive federal funds.

Nearly 7% of the residents had been physically aggressive-defined as hitting, shoving, scratching, or engaging in sexual abuse-in the week before their assessment. Furthermore, 10.5% of residents had been verbally aggressive-threatening, screaming, cursing-the week before their assessment.

The study could not determine whether aggression had been directed at fellow residents, visitors, or staff.

After adjusting for factors such as age, sex, and degree of cognitive impairment, the investigators found that following were linked with physical aggression:

• Depression (odds ratio=3.3; 95% confidence interval=3.0 to 3.6)
• Delusions (OR=2.0; 95% CI=1.7 to 2.4)
• Hallucinations (OR=1.4; 95% CI=1.1 to 1.8)
• Constipation (OR=1.3; 95% CI=1.2 to 1.5)

Similarly, the following were linked with verbal aggression, although for constipation the results only bordered on statistical significance:

• Depression (OR=4.9; 95% confidence interval=4.5 to 5.3)
• Delusions (OR=2.5; 95% CI=2.2 to 2.8)
• Hallucinations (OR=1.6; 95% CI=1.3 to 1.9)
• Constipation (OR=1.1; 95% CI=1.0 to 1.2)

"It is not clear whether physical aggression may be related to factors that predispose to constipation (e.g., anticholinergic medications such as tricyclic antidepressants), the symptoms associated with constipation, or interventions such as suppositories that may elicit a defensive action by some residents," the researchers said.

"We found that aggressive behavior among residents was associated with depression, delusions, and hallucinations, and that physical aggression was also associated with constipation," they said. "All of these factors may be amenable to intervention and, in addition to reducing the morbidity associated with these entities themselves, effective treatment may reduce the risk of violence in nursing homes."

The study did not find significant associations with factors one might expect to underlie aggressive behavior, such as respiratory tract infections, urinary tract infections, fever, or reported pain, the investigators said.

The authors pointed out that "because this was a cross-sectional observational study and the Minimum Data Set does not specify a sequence of onset for outcome and exposure variables, we cannot assert a temporal link between resident characteristics and either physical or verbal aggression."