Dementia and Falls in Older Adults: New Diagnosis More Common Within Year of Injury

Falls in older adults are associated with increased risk for incident dementia diagnoses, according to study results published in JAMA Network Open.

Limited information is available on the effect of falls in older adults on the risk for dementia; however, understanding this association may be beneficial for the early detection of dementia in this population.

Researchers of a retrospective cohort study assessed the link between falls and future diagnosis of dementia in older adults in the United States.

Eligible participants were older adult beneficiaries enrolled in the Medicare Fee-for-Service with a diagnosis of traumatic injury (defined by the International Classification of Diseases [ICD]codes), which resulted in an emergency department (ED) visit or hospitalization.

Date on patient sociodemographic factors, comorbidities, and injury severity were also collected, measured using self-report, Charlson Comorbidity Index (CCI), and Injury Severity Score (ISS), respectively.

Primary outcome variable was dementia diagnosis, defined by ICD, Ninth Revision (ICD-9) codes. Primary study outcome was risk for incident dementia diagnosis after a fall.

A total of 2,453,655 individuals (mean age, 78.1; women, 62.1%; White, 91.0%), of whom 1,228,847 experienced a fall, were included in the analysis.

Mechanism of injury in half of the participants was from a fall; approximately one-fourths were admitted to a nursing facility; and half of the participants had at least 1 comorbidity.

Participants with vs without a fall as the mechanism of injury were older and more likely to be admitted to a nursing facility or be hospitalized, as well as more likely to have an ISS of 9 or higher, have surgery for hip fracture, and receive a diagnosis of delirium.

The researchers noted that an incident dementia diagnosis was more common after a fall compared with other injury mechanisms (10.6% vs 6.1%; P <.001). New dementia diagnoses after a fall gradually occurred over a period of 1 year; however, there was a sharp increase in the first 1 to 2 weeks after the fall. A total of 21,658 dementia diagnoses were noted after a fall.

The risk for incident dementia was 63% higher in participants who experienced a fall vs other mechanism of injury (hazard ratio [HR], 1.63; 95% CI, 1.61-1.64; P <.001). After controlling for covariates, there was a 21% increase in risk for new dementia diagnosis (HR, 1.21; 95% CI, 1.20-1.21).

Falls were associated with a 10% vs 27% increased hazard of new dementia diagnosis in those with vs without recent admission to a nursing facility, respectively (HR, 1.10; 95% CI, 1.09-1.12 and HR, 1.27; 95% CI, 1.26-1.28, respectively; both P <.001).

In addition, patients who experienced a fall were more likely to be hospitalized than have an ED visit (69.7% vs 45.9%; P <.001). Further, the rate of incident dementia diagnoses across all mechanisms of injury was higher among inpatient admissions vs ED visits (12.2% vs 7.5%; P <.001).

Limitations were the retrospective, observational nature of the study that limited the ability to draw conclusions from the findings; inaccuracies in coding for injury mechanisms and potentially missing out on preexisting diagnoses; and lack of access to prescription data, which may have included medications that increased risk for falls.

Overall, the researchers noted, “These results suggest that cognitive screening should be implemented for older adults who have experienced a fall that results in an emergency department visit or hospital admission.”

“Implementing cognitive screening after falls will require a multidisciplinary effort involving the breadth of clinicians who care for older adults after a fall, ranging from trauma surgeons to geriatricians and primary care physicians,” the researchers added. “Cognitive screening recommendations should be included in the American College of Surgeons Geriatric Trauma Best Practices Guidelines and other guidelines concerning the care of injured older adults.”