Research Projects
Impact of Feeding Mode on Advanced Dementia Patients with Feeding Problems

Objective and Significance:

Feeding problems are common in patients with advanced dementia and can indicate progression of the disease course towards the end of life.1 Prevalence of feeding tubes in advanced dementia patients with feeding problems is high in Hong Kong. In a local study of advanced cognitively impaired residents in residential care homes, 53% were receiving tube feeding.2 By contrast, in the United States, the prevalence of feeding tubes among nursing home residents with severe cognitive impairment is 18-34% and the insertion rate has been declining over the past decade.3,4

Feeding tubes are commonly inserted because of perceived benefits of reduction of aspiration pneumonia and longer survival.5-7 However, prior observational studies have not found conclusive evidence that feeding tubes prevent aspiration pneumonia or prolong survival in patients with advanced dementia.8-12 In 2014, the American Geriatrics Society issued a position statement to recommend against feeding tubes for older adults with advanced dementia given the potential benefits “do not outweigh substantial associated treatment burdens” and favoured careful hand feeding as an alternative.13 In careful hand feeding, a trained carer feeds the patient orally using feeding techniques to stimulate oral intake and reduce the risk of aspiration with the goal of maximizing comfort and quality of life for the patients.14

However, one limitation to the generalizability of many prior studies is the inclusion of patients with percutaneous endoscopic gastrostomy (PEG) tubes.15-17 In some places in Asia including Hong Kong and Malaysia, nasogastric tube (NGT) feeding is predominantly used for long-term enteral feeding among older adults.14,18 Differentiating the type of feeding tube is important given higher rates of mortality and aspiration pneumonia are associated with long term NGT feeding compared with PEG tubes.19 Therefore, further research is needed to examine the outcomes of NGTs specifically in patients with advanced dementia.

Another limitation of prior studies is the inclusion of community-based advanced dementia patients living at home or in nursing homes.11,20 Yet, in Hong Kong and other locations, feeding tubes are most commonly inserted in patients with advanced dementia when hospitalized.14,20 Hospitalized patients with advanced dementia have a high six-month mortality rate of 50%.21,22 Therefore, it is important to examine the outcomes for the subset of advanced dementia patients who are hospitalized when feeding tube insertion is considered.

Furthermore, tube feeding can adversely affect the quality of life of dementia patients due to increased agitation, use of physical or chemical restraints to prevent tube removal, and hospital readmissions for tube-related complications.8,9,20 Tube feeding may even lead to increased institutionalization due to the need for trained carers for administering enteral nutrition. However, data is lacking on the adverse effects of nasogastric tube feeding in advanced dementia patients.10

This study aims to address these gaps by examining the impact of NGT feeding compared with oral feeding for advanced dementia patients with feeding problems on survival, incidence of aspiration pneumonia, acute care utilization, and institutionalization rates. Findings from this study will provide important data on the potential benefits and harms of NGT feeding for health care providers, families and patients making decisions regarding NGT insertion for long-term enteral nutrition.

Research Plan and Methodology: Subjects: Hospitalized advanced dementia patients with feeding problems with consideration for NGT insertion during the index hospitalization will be recruited for the study. Methods: This prospective cohort study will enroll subjects only after their family surrogate decision-maker has made a decision on the mode of feeding. Subjects will be assigned into one of two groups: 1. Nasogastric tube feeding (NGT) group - Patients initiated on NGT feeding after their family agreed to NGT insertion during the index hospitalization. 2. Oral feeding group - Patients continued or resumed on oral feeding after documented family refusal of NGT placement during the index hospitalization Data processing and analysis: A descriptive analysis of the demographic data and baseline characteristics will be performed. Chi-square test and Fisher’s exact test will be used for comparisons of categorical variables between the two groups. For ordinal variables (such as albumin concentration grouped in quartiles), the Mantel-Haenszel test for linear association will be used. Differences in the means of continuous measurements will be tested by Student’s t test and checked by the Mann-Whitney U test. Patients who are lost to follow up or followed until study end date will be censored at study end. All primary and secondary outcomes will be analysed based on the original group assignment. Survival time will be calculated from the date of enrolment to the date of death. Survival will be assessed by the Kaplan-Meier method and different survival functions compared using log-rank test. To determine factors that influence survival, a series of univariable Cox proportional hazards regression models examining the different covariables to time of death will be performed. Variables of borderline significance (P<.15), and variables that have been previously shown to be related to survival in advanced dementia (i.e. dementia stage, sex, age, prior pneumonia, presence of a pressure ulcer, presence of a feeding tube, Charlson morbidity score, and residence at home vs nursing home) will be included in a forward, stepwise multiple logistic-regression model. Multivariable regressions will be used to compare the two arms in the incidence rates of aspiration pneumonia, emergency room attendance rates, hospital readmissions, total hospital inpatient days, and institutionalization rates, with adjustment for potential clinical-demographic confounders. Statistical analysis will be performed with SPSS 11.5 (SPSS, Chicago, IL). The level of significance will be set at 0.05 (two-tailed).

Dr JKY Yuen, Department of Medicine

Biography
jkyuen@hku.hk

For more information or to express interest for this project, please email the supervisor or the specified contact point in the project description.  Interested candidates are advised to enclose with your email:

1. your CV,
2. a brief description of your research interest and experience, and
3. two reference letters (not required for HKUMed UG students seeking MRes[Med]/URIS projects).

Information on the research programme, funding support and admission documentations could be referenced online at the Research Postgraduate Admissions website. General admission enquiries should be directed to rpgmed@hku.hk.

HKUMed MBBS students interested in the Master of Research in Medicine (MRes[Med]) programme may visit the programme website for more information.  

HKUMed UG students interested in the Undergraduate Research Internship Scheme (URIS) may visit the scheme’s website for more information.