Incidence of Tube Feeding in 7174 Newly Admitted Nursing Home Residents With and Without Dementia

Abstract

Background:

Tube feeding is a common form of long-term nutritional support, especially for nursing home residents, of whom many have dementia.

Objective:

Estimating the incidence of feeding tube placement in nursing home residents with and without dementia.

Methods:

Using claims data, we studied a cohort of newly admitted nursing home residents aged 65 years and older between 2004 and 2009. Analyses were stratified by dementia. We estimated incidence rates and performed multivariate Cox regression analyses.

Results:

The study cohort included 7174 nursing home residents. Over a mean follow-up of 1.3 years, 273 people received a feeding tube. The incidence per 1000 person-years was 28.4, with higher estimates for patients with dementia. When adjusting for age, sex, and level of care as a time-dependent covariate, influence of dementia decreased to a nonsignificant hazard ratio.

Conclusion:

It seems that not dementia itself but the overall clinical condition might be a predictor of tube feeding placement.

Keywords

feeding tube incidence dementia nursing home nursing home residents health services research

Introduction

Enteral feeding is a common method of long-term nutritional support to compensate for low nutritional intake. Initially used in pediatric patients in the 1980s, enteral feeding with a feeding tube (percutaneous endoscopic gastrostomy or jejunostomy) is today used in patients of different ages and with different diseases,¹ although the majority is placed in older adults.² Age-related factors such as the loss of appetite or sensory function and other chronic diseases promote malnutrition in this age-group.³ Dementia is one of the most common age-related chronic diseases,⁴ entailing swallowing disorders (dysphagia) and an inability to eat independently (apraxia) or to recognize food and thus reinforcing malnutrition.^3,5
-7 The long-term care needs of persons with advanced dementia mostly include support and nursing home admission. Most nursing home residents are meanwhile people with dementia.^8,9

In particular, the use of feeding tubes in patients with dementia is a matter of some controversy. The decision to use a feeding tube is a complex, emotive issue, especially from an ethical point of view.^10,11 However, there is no conclusive evidence for tube feeding in terms of survival time, quality of life, mortality, or physical functioning for people with advanced dementia,¹⁰ and practice management guidelines advise caution and do not recommend the use of tube feeding in advanced dementia.^3,12,13

Despite this controversy, studies on the prevalence or incidence of tube feeding in nursing home residents are rare,^1,14 especially for Germany.^2,15,16 International data on the epidemiology of feeding tubes in nursing home residents mostly refer to the US population^1,17 and often focus on patients with cognitive impairment.^18,19 The reported data for the United States vary between the analyzed regions but reveal that up to one-third of nursing home residents with advanced dementia have a feeding tube.¹⁸ Studies from Germany and other European countries found lower prevalences, with less than 10% of nursing home residents having feeding tubes regardless of dementia status.^14,15,20 Information on the incidence of feeding tube placement is scarce. To our knowledge, only Kuo and colleagues from the United States dealt with this question and found a rate of 54 feeding tubes per 1000 residents with advanced dementia who were followed for up to 1 year to see whether they got a feeding tube.¹

We therefore aim to study the incidence of feeding tube placement in newly admitted nursing home residents aged 65 years and older, focusing on differences between persons with and without dementia.

Research Design and Methods

Data Source, Study Population, and Covariates

For the present analysis, claims data from the Gmünder ErsatzKasse (GEK, now BARMER GEK) were used. The GEK was a German statutory health insurance company operating nationwide which covered about 2% of the German population. Our study included all insurants of the GEK aged 65 years and older, who were newly admitted to a nursing home (cohort entry) between January 1, 2004, and December 31, 2009, subsequent to a continuous insurance period of at least 365 days without nursing home placement. In order to obtain this information, we used data pertaining to compulsory German Long-Term Care Insurance (“Gesetzliche Pflegeversicherung”). In addition to the type of benefit (here: residential care), we also have information on dates of changes in level of care—ranging from care level I (considerable need of care) to care level III (most heavily care dependent). Hardship cases (care level IV) are assigned to care level III.^21,22 A recently published systematic review on the German health care and long-term care system describes the graduation of care levels in detail (Supplementary data).²² All residents in nursing homes are in principle assigned to a care level on the day of cohort entry. However, it is possible that the situation of some residents improved during follow-up and that the criteria for a specific level of care were no longer fulfilled, in which case the residents in question were assigned to level 0. Assessments as well as decisions on changes in the level of care are made by the independent association of the German Health Insurance Medical Service.

The placement of a feeding tube including percutaneous endoscopic gastrostomy and jejunostomy as well as tube duodenostomy and jejunostomy could be identified in both the outpatient and the hospital data (codes available upon request). The exact dates of feeding tube placement were given in the data. Persons with a feeding tube before cohort entry were excluded from the study.

In order to obtain information on dementia, we used ambulatory (outpatient) diagnosis. Dementia was determined if a nursing home resident had at least 1 diagnosis within the quarter of institutionalization (because diagnoses can only be related to a calendar quarter). The following International Classification of Diseases codes were used for identifying dementia diagnosis: F00.x, F01.x, F02.0, F02.3, F03, G30.x, G31.0, G31.1, G31.82, G31.9, and R54. This definition was also used elsewhere.^23,24

Statistical Analysis

The main outcome was the placement of a feeding tube. The follow-up started with the day of institutionalization and ended with the placement of a feeding tube, death, or at the end of follow-up (December 31, 2009)—whichever came first.

All analyses were stratified by dementia (yes/no). First, we calculated incidence rates per 1000 person-years (PY) for feeding tube placement by dividing the number of incident cases by the accumulated time under risk. The 95% confidence intervals (95% CIs) were estimated using the substitution method with Poisson distribution.²⁵ We then calculated hazard ratios (HR) with 95% CI using Cox proportional hazard regression models for time to placement of a feeding tube with stepwise adjustment for several covariates. In the first model, we only entered dementia status (yes/no). In the second model, we further added age (continuous) and sex (male vs female) as independent variables. In the third model, the current level of care (3 categories) was additionally entered in this model as a time-dependent covariate. The level of significance was 0.05. We performed all statistical analyses using SAS for Windows version 9.2 (SAS Institute Inc, Cary, North Carolina).

Results

A total of 7635 people were newly admitted to a nursing home between 2004 and 2009, 461 of whom had to be excluded because a feeding tube had already been placed prior to admission. In a large proportion of cases, this procedure had taken place 30, 60, or 90 days preceding institutionalization (42.1%, 66.6%, and 79.2%). Hence, the population at risk consists of 7174 nursing home residents (Figure 1).

Figure 1.

Sampling frame.

These persons were on average 81.6 (standard deviation [SD]: 7.4) years old, and 54.8% were female and 50.1% had care level I. About half (48.6%) of the residents had a diagnosis of dementia at the time of institutionalization, and they were slightly older than people without dementia. In both cohorts, about 55% were female. The residents were particularly often in receipt of care levels I and II (with dementia: 47.0% and 42.3%; without dementia: 53.0% and 39.6%). The baseline characteristics are shown in Table 1.

Table 1.

Baseline Characteristics of the Study Population.

Characteristics	Study Population
	With Dementia (n = 3487)		Without Dementia (n = 3687)		Total (N = 7174)
	n	%	n	%	n	%
Age, in years
65-74	493	14.10	815	22.10	1308	18.20
75-84	1623	46.50	1644	44.60	3267	45.50
85+	1371	39.30	1228	33.30	2599	36.20
Age, mean, SD	82.3	7	80.9	7.6	81.6	7.4
Sex
Male	1578	45.30	1662	45.10	3240	45.20
Female	1909	54.70	2025	54.90	3934	54.80
Care Level
Level I	1637	47.00	1955	53.00	3592	50.10
Level II	1476	42.30	1461	39.60	2937	40.90
Level III	374	10.70	271	7.40	645	9.00

Abbreviation: SD, standard deviation.

The mean follow-up was 1.3 years (SD: 1.4), 1.4 years for those with and 1.3 years for those without dementia (the number of persons newly admitted per year was 882, 987, 1199, 1197, 1352, and 1557 for 2004, 2005, 2006, 2007, 2008, and 2009, respectively). During follow-up, a total of 4118 persons died and a total of 273 persons received a feeding tube (the number of persons per year was 20, 37, 49, 50, 54, and 63 for 2004, 2005, 2006, 2007, 2008, and 2009, respectively). The overall incidence rate of feeding tube placement was 28.4 per 1000 PY, with higher estimates for persons with dementia in comparison to those without (33.1 vs 23.3 per 1000 PY). The incidence was higher in males than in females and decreased with age in both groups. All incidence rates are shown in Table 2.

Table 2.

Incidence Rates of Feeding Tubes per 1000 Person-Years (PY) in Newly Admitted Nursing Home Residents Aged 65 Years and Older.

Category	With Dementia				Without Dementia				Total
Category	Cases	PY	Rate	95% CI	Cases	PY	Rate	95%CI	Cases	PY	Rate	95% CI
Age, in years
65-74	43	828	51.9	37.6-69.9	28	904	31	20.6-44.8	71	1732	41	32.0-51.7
75-84	83	2440	34	27.1-42.2	52	2129	24.4	18.2-32.0	135	4569	29.5	24.8-35.0
85+	39	1712	22.8	16.2-31.1	28	1597	17.5	11.7-25.3	67	3309	20.2	15.7-25.7
Sex
Male	88	1851	47.6	38.1-58.6	49	1764	27.8	20.6-36.7	137	3615	37.9	31.8-44.8
Female	77	3130	24.6	19.4-30.7	59	2865	20.6	15.7-26.6	136	5995	22.7	19.0-26.8
Total	165	4981	33.1	28.3-38.6	108	4629	23.3	19.1-28.2	273	9610	28.4	25.1-32.0

Abbreviations: PY, person-years; 95% CI, 95% confidence intervals.

The Cox regression confirms the statistically significant influence of dementia on placing a feeding tube in the crude model (HR: 1.43; 95% CI: 1.12-1.82). In a second model, age and sex were entered as further independent variables not changing the effect of dementia (Table 3). However, when further entering level of care as a time-dependent covariate into the third model, the influence of dementia decreased to a nonsignificant HR of 1.13 (95% CI: 0.88-1.45). The level of care had a high influence on the chance of receiving a feeding tube; for instance, it was 5.79 times more likely for persons in care level III in comparison to residents in care level I/0. Age was also a significant predictor, with higher age decreasing the chance of receiving a feeding tube. Being male was associated with a 1.35 times higher chance of receiving a feeding tube compared to females.

Table 3.

Cox Proportional Hazard Regression Models for Factors Associated With Tube Feeding in Newly Admitted Nursing Home Residents Aged 65 Years and Older^a.

	Model 1	Model 2	Model 3
	HR (95% CI)	HR (95% CI)	HR (95% CI)
Dementia (vs no dementia)	1.43 (1.12-1.82)	1.46 (1.14-1.86)	1.13 (0.88-1.45)
Age (per year)		0.96 (0.94-0.98)	0.97 (0.95-0.98)
Male (vs female)		1.42 (1.12-1.82)	1.35 (1.06-1.72)
Care level (time dependent)
No level of care/level I			1.00 (reference)
Level II			2.87 (2.07-3.97)
Level III			5.79 (4.03-8.31)

Abbreviations: HR, hazard ratio; 95% CI, 95% confidence interval.

^an = 7174.

Discussion

The application of feeding tubes for nursing home residents is an important and relevant issue. A trend analysis from the United States shows an increase in the use of feeding tubes for elderly patients during hospital stays—especially for patients with dementia.¹⁷ Existing studies from Germany focus on analyzing the prevalence of feeding tube insertion in nursing homes,^15,16,20 revealing that between 6.6% and 7.8% are tube fed. Studies from other countries vary considerably according to methodology, setting, and the population studied.^1,18,19,26 Prevalences of feeding tubes for nursing home residents with dementia are even higher—especially in studies from the United States, which report up to one-third of nursing home residents with advanced cognitive impairment being fed by tube.¹⁸ Only few studies dealt with the incidence of feeding tubes in nursing home residents—the studies were often restricted to patients with advanced dementia.¹ Hence, a direct comparison of our results to other studies is difficult. However, there is no reliable data from Germany regarding the incidence of feeding tubes for nursing home residents with or without dementia.

The first interesting result was that 461 nursing home residents had to be excluded because of an already existing feeding tube that most of them (42.1%) received in the 30 days before nursing home admission. A comparable proportion of patients already equipped with a feeding tube before admission to a nursing home was also found in a German study by Wirth and colleagues.¹⁵ In our study, reasons for the hospital stay were, for example, cerebral bleeding or a stroke. After their discharge from hospital, the patients in question were promptly admitted to nursing homes. This is also reflected in the literature: A considerable percentage of feeding tubes for residents is applied in the context of hospital stays¹⁹ and often before nursing home admission.¹⁵

In our cohort, about 50% of the nursing home residents have dementia. This is well known from previous studies^8,9,27 as is also the higher number of women in this setting. Our study results are similar to those found in the literature. Moreover, a somewhat higher percentage of patients with dementia were in care level II and III and were therefore more likely to be more care dependent than residents without dementia diagnosis.

Incidence Rate of Feeding Tubes

In total, the incidence rate of newly admitted nursing home residents aged 65 years and older is 28.4 per 1000 PY. However, with increasing age the incidence rates decrease. One explanation could be that with increasing age the possible benefits of a feeding tube do not outweigh the risks entailed in the feeding tube insertion procedure. Hence, physicians and relatives might choose not to insert a feeding tube.²⁸

Nevertheless, the incidence rate is higher in residents with dementia. This could be due to the fact that dementia is often associated with eating problems like swallowing difficulties or the inability to eat independently (apraxia) or to recognize food.^3,6 However, there is no conclusive evidence that feeding tubes in patients with advanced dementia are a convenient method for prolonging life or improving quality of life.¹⁰ This, therefore, constitutes the ethical dilemma: On the one hand, clinicians feel pressured by relatives as well as institutional or societal directives to initiate a nutritional therapy to prevent the patient from facing starvation. On the other hand, there is no conclusive evidence for an improved quality of life after inserting a feeding tube in patients with advanced dementia. Current data on feeding tubes in patients with earlier stages of dementia are rare, inconclusive, and a balanced, individual case-by-case decision is required involving the physicians, care givers, and relatives.³

Factors Associated With Tube Feeding

Initially, in the second model – where sex and age were included as further independent variables – the influence of dementia on feeding tube placement was not changed. Age is a significant factor, showing that with increasing age the chance of being given a feeding tube decreases. Being male seems to be a significant predictor for feeding tube insertion. We have no simple explanation for this result. However, this result of higher rates in males was also shown by Smoliner et al²⁹ who discuss the possibility of younger age and better functional status being an explanation. In our study, men are also slightly younger than the women but not less care dependent. In general, sex as a predictor for institutionalization is discussed controversially in the literature on the subject of institutionalization.³⁰

In particular, the results of the third model are of special interest: When adding the time-dependent care level as a further independent variable into the model, the HR of dementia becomes nonsignificant. On the other hand, the current respective care level has a large influence on our outcome: Residents on care level III have a 6-time higher chance to get a feeding tube than residents on care level I or 0. Hence, given the limitations of the study, we assume that not dementia by itself, but the overall clinical condition and the sum of the differential consequences of the disease—as the expression of one or more diseases—influence feeding tube placement.

Strength and Limitations

The major strength of our first study on this highly relevant issue is the large sample size of more than 7000 newly admitted, unselected nursing home residents who could be followed for up to 6 years. Field studies on older adults with cognitive impairment often face selection bias and, therefore, an underrepresentation of relevant patient groups.³¹ However, analyzing administrative data allowed us to examine all nursing home residents insured by the above-named statutory health insurance company regardless of frailty or degree of cognitive impairment.

Yet, there are some limitations to our study. We have no further clinical information about the residents such as level of restrictions in activities of daily living, nutritional status, and severity of dementia or indications for procedures or treatment. Especially, the last point is significant since it makes a comparison to other studies analyzing the insertion of feeding tubes in patients with advanced dementia difficult. Such information is lacking because administrative data are not collected for research purposes. Moreover, it was not possible to differentiate between the different types of dementia in the present study. The majority of dementia diagnoses are coded by general practitioners who rarely initiate further diagnostics for differentiation. Hence, it is not surprising that about 70% of all dementia diagnosis were coded as “F03: unspecific dementia.” This is known from earlier studies using the same database.³² Due to small numbers, we were not able to estimate changes in the incidence of feeding tube placement over the years.

Our data represent real-world health care utilization patterns and represent only one of the several health insurance funds. There are identifiable differences between insurants of the different German health insurances with respect to age, sex, socioeconomic status, morbidity, and utilization of health care resources. For example, the proportion of men in the GEK is higher than that of the total German population. Thus, a direct transfer of the results based on a single fund to the total German population should be done with caution.^33,34 Moreover, the data are up to 10 years old. It is possible that the practice of feeding tube placement has changed over the past few years due to changing awareness and recommendations regarding tube feeding in advanced dementia. However, these results provide some preliminary substantive evidence on the incidence of tube feeding in newly admitted nursing home residents.

Conclusion

This is the first study from Germany analyzing the incidence of feeding tube insertion in newly admitted nursing home residents. Previous studies focused on prevalences in one selected setting, like the hospital sector, or on specific regional settings.^2,16 Incidence rates are higher in nursing home residents with dementia in comparison to those without. With increasing age the rates decrease. After adjusting for age, sex, and current care level, dementia was no longer a significant predictor of feeding tube insertion in the multivariate analysis. Given the limitations of the study, it appears that not dementia itself but rather the overall clinical condition seem to be a predictor for feeding tube placement. Further research is needed for analyzing predictors for feeding tubes, including organizational and staffing situations as well as clinical information and changes over time.

Footnotes

Ethical Standards

The study was conducted according to the principles expressed in the Declaration of Helsinki. We took the STROBE statement and the criteria of a national good practice guideline^35,36 into consideration. According to the Good Practice of Secondary Data Analysis, a national guideline for the use of administrative databases, no approval of an ethical committee is required.³⁶

Authors’ Note

JS and FH performed the data analysis and JS wrote the manuscript. All authors interpreted the data, critically revised the manuscript, read, and approved the final manuscript.

Declaration of Conflicting Interests

The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: We thank the Gmünder ErsatzKasse (GEK, now BARMER GEK) for providing the data analyzed in our study. This work was supported by grants from the Jackstädt-Stiftung.

Supplemental Material

The online [appendices/data supplements/etc] are available at .

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