STATEMENT OF PROBLEM: Oral health-related quality of life (OHRQoL) is a 
subjective measure that assesses a person's perception of oral health. Patients 
with Alzheimer disease (AD) suffer from impaired cognitive function and a 
compromised ability to perform activities of daily living. Further exploration 
is needed to clarify whether OHRQoL is negatively impacted by cognitive 
degeneration and oral health conditions among patients with AD.
PURPOSE: The purpose of this systematic review was to increase understanding of 
OHRQoL among patients with AD and explore factors that may affect OHRQoL.
MATERIAL AND METHODS: Searches were conducted in PubMed, the Cochrane Library 
database, Medline, EBSCO, ProQuest, and EMBASE until August 30, 2018, with no 
date restrictions. The initial search targeted quantitative observational 
studies published in English that included the keywords AD, oral, prosthesis, 
and OHRQoL. Data extraction was independently conducted by 2 reviewers. OHRQoL 
was investigated as the outcome. Cognitive status and oral health conditions 
were treated as exposures. Tools used to measure OHRQoL included the Geriatric 
Oral Health Assessment Index (GOHAI) and the Oral Health Impact Profile. The 
research adhered to the Preferred Reporting Items for Systematic Reviews and 
Meta-Analyses guidelines.
RESULTS: Six studies were included. The sample sizes ranged from 30 to 226 
participants, 5 studies used cross-sectional designs, and 1 was a nonrandomized 
controlled trial. Three studies reported higher OHRQoL scores among participants 
with AD than those among controls, but only 1 study showed a statistically 
significant difference. A statistical analysis was conducted with 4 studies that 
reported GOHAI scores, and no significant differences were found in GOHAI scores 
between participants with AD and controls (standard mean difference: 0.09; 95% 
confidence interval: -0.66 to 0.85). All studies that explored factors affecting 
OHRQoL showed different associations between cognitive impairment, oral health 
conditions, and OHRQoL. One study showed that cognitive impairment was 
negatively associated with OHRQoL. Three studies found oral health conditions 
(including periodontitis, gingival bleeding, probing depth >4 mm, and number of 
natural teeth) impaired the OHRQoL of participants with AD. Three studies 
reported that prosthetic type and quality positively affected OHRQoL among 
participants with AD.
CONCLUSIONS: OHRQoL may not fully represent actual oral health problems of 
patients with AD. Clinical dentists should evaluate oral problems in this 
population, preferably by using both subjective and objective examinations, 
including oral and dental conditions. This will ensure oral problems among 
patients with AD can be detected early and timely treatment provided.