Dementia in TAVR Patients Raises Several Risks, But Not Mortality

Among patients undergoing transcatheter aortic valve replacement (TAVR), a history of dementia is associated with higher rates of in-hospital delirium, a longer hospital stay and greater chance of discharge to a rehabilitation facility — but not with higher rates of in-hospital mortality. So finds a nationwide cohort study that used propensity-score matching to compare nearly 3,000 pairs of TAVR patients with and without baseline dementia.

The analysis, conducted by researchers at Cleveland Clinic and several other U.S. medical centers, was published online Feb. 11 in the Journal of the American Geriatrics Society.

“Pre-TAVR decision-making is especially challenging in patients with cognitive impairment,” says corresponding author Ankur Kalra, MD, Medical Director of Clinical Research for Regional Cardiovascular Medicine at Cleveland Clinic. “This study’s findings add a new dimension for evidence-based discussion among patients, families and physicians about whether TAVR is advisable for a candidate with dementia.”

A dearth of data on TAVR in dementia

TAVR has become a common treatment option for severe symptomatic aortic stenosis in patients 65 or older, an age cohort in which the prevalence of dementia is high. Nevertheless, prior to this study, a dearth of post-TAVR outcomes data in patients with dementia left scant guidance for counseling such individuals.

Established TAVR scoring systems, such as the EuroSCORE and Society of Thoracic Surgeons score, do not quantitatively factor in cognitive dysfunction, the study authors point out. “In some patients, the presence of dementia may be the only issue to raise concern about whether to undergo the procedure,” notes co-author Anmar Kanaa’N, MD, a study co-author and director of the TAVR program at Cleveland Clinic Akron General.

The study and its findings

To shed more light on the issue, the investigators queried the Nationwide Inpatient Sample database from January 2012 to September 2015 to identify all TAVR patients 65 or older as well as those with a diagnosis of dementia.

“This date range, which preceded FDA approval of TAVR for patients at intermediate and low surgical risk, was intentionally chosen to capture a population at high surgical risk,” Dr. Kalra explains. “We reasoned that such patients would likelier be older and have a higher prevalence of dementia.”

Of 57,805 patients undergoing TAVR in the database, 2,910 (5%) had a diagnosis of dementia, with a mean age of 84.3 ± 4.8 years. Propensity-score matching was used to couple these patients with comparable cohort counterparts without dementia, yielding a total of 2,895 well-balanced matched pairs.

Comparison of in-hospital outcomes in the matched cohort revealed the following differences between patients with and without dementia, respectively:

• Delirium: 7.4% vs. 3.6% (OR = 2.13; 95% CI, 1.26-3.61; P < 0.01)
• Bleeding requiring transfusion: 14.7% vs. 8.6% (OR = 1.82; 95% CI, 1.26-2.63; P < 0.01)
• Length of stay: 6.75 vs. 6.11 days (OR = 1.11; 95% CI, 1.03-1.19; P < 0.01)

Patients with dementia also were significantly more likely to be discharged to a rehabilitation facility (45.8% vs. 31.6%; OR = 2.27 [95% CI, 1.67-3.08]; P < 0.01).

Notably, however, in-hospital outcomes of mortality, acute kidney injury, stroke, pacemaker implantation and vascular complications were statistically comparable between the two groups.

Takeaways for patient counseling

The authors note that these findings underscore several important considerations for discussion in shared decision-making between the heart team and TAVR candidates and their families when cognitive impairment is an issue:

• Dementia entails additional risks from TAVR. These include in-hospital delirium, bleeding, longer hospital stay and discharge to a rehabilitation facility.
• TAVR is reasonably safe in patients with dementia. Most patients do not develop complications following the procedure, and in-hospital death rates are the same as for patients without cognitive impairment.
• TAVR has important potential cognitive and functional benefits. Although the current study did not investigate this issue, other studies indicate that TAVR may improve or stabilize cognitive function by increasing cerebral blood flow, in addition to enabling more physical activity.

“Although TAVR can be safely performed in patients with dementia, goals of such treatment and expectations of patients and their family members should be carefully considered prior to offering treatment,” says study co-author Samir Kapadia, MD, Chair of Cardiovascular Medicine at Cleveland Clinic.

Guidance for better risk assessment

The authors urge incorporation of cognitive function into the standardized workup for patients considering TAVR. Although society guidelines recommend factoring in cognitive status, a standardized score threshold has not been established and will require more study.

Dr. Kalra notes that the current investigation was limited by lack of information about the severity and type of patients’ dementia and about patients’ quality of life following TAVR, adding that quality of life looms large in decisions around medical interventions in patients with dementia.

“TAVR candidates should undergo a comprehensive geriatric and cognitive assessment to help determine their post-procedural risk of functional decline,” concludes study co-author Joseph Lahorra, MD, a cardiothoracic surgeon at Cleveland Clinic Akron General. “This study provides a better understanding of the impact of dementia on TAVR outcomes. We hope it will contribute to better-informed decision-making.”