Physicians' Attitudes toward Tube Feeding Chronically 111 Nursing Home Patients SABINE M. VON PREYSS-FRIEDMAN, MD, RICHARD F. UHLMANN, MD, MPH, KEVIN C. CAIN, PhD Objective: To d e t e r m i n e attitudes o f p h y s i c i a n s t o w a r d the limitation o f tube f e e d i n g i n chronically ill n u r s i n g h o m e p a t i e n t s a n d the influences o f p a t i e n t p r e f e r e n c e s a n d o t h e r p a t i e n t a n d p h y s i c i a n variables o n these decisions. Design: Questionnaire-based, mailed survey. Hypothetical case s c e n a r i o s derived by f r a c t i o n a l f a c t o r i a l design to d e t e r m i n e the influences o f p a t i e n t a n d f a m i l y preferences, age, life expectancy, p h y s i c a l a n d cognitive f u n c t i o n i n ~ direct scaling to d e t e r m i n e the influences o f legal a n d cost considerations.
Participants: R a n d o m l y selected n a t t o n a l samples o f American Geriatrics Society a n d A m e r i c a n Medical Associatton m e m b e r s ( n = 141, p a r t i c i p a t i o n rate 41%).
Main results: Nearly all p h y s i c i a n s indicated they w o u l d w i t h h o l d (95%) o r w i t h d r a w (92%) tube f e e d i n g in a t least o n e o f the 16 s c e n a r i o s studied. P h y s i c i a n decisions were m o s t highly associated with p a t i e n t preferences, f o l l o w e d by f a m i l y preferences, life expectancy, a n d cognitive status ( p < 0.02 to < 0.001). When p a t i e n t s a n d f a m i l i e s agreed, p h y s i c i a n s c o n c u r r e d in 87% to 95% o f the decisions. However, w h e n p a t i e n t s a n d f a m i l i e s disagreed, p h y s i c i a n s c o n c u r r e d with p a t i e n t s in only 48% to 55% o f the decisions. I n c r e a s i n g p h y s i c i a n c o n c e r n r e g a r d i n g legal a n d cost c o n s i d e r a t i o n s was significantly associated with significantly h i g h e r a n d l o w e r likelihoods o f tube f e e d i n ~ respectively ( p < 0.05). Conclusions: These results suggest that the m a j o r i t y o f study p h y s i c i a n s a r e willing to limit tube f e e d i n g in nursing h o m e p a t l e n t s u n d e r some circtanstances. P a t t e n t p r e f erences a p p e a r to be the m o s t i m p o r t a n t f a c t o r i n these decisions, but m a y n o t be honored, especially i f the wishes o f p a t i e n t s a n d their f a m i l i e s a r e n o t in concurrence. Key words: aging, attitudes; decision making, n u r s i n g homes; tube f e e d i n g , medicolegaL J GEN INTERN MED 1992;7:46- 51.
THE LIMITATIONOF artificial hydration and nutrition is
one of the most controversial issues in medicine. Patients are generally considered to have the right to refuse life-sustaining treatment. ~ However, the influe n c e of patients' preferences for artificial hydration and nutrition on physicians' decision making is unclear. For e x a m p l e , some physicians and long-term care institutions believe that the right to refuse life-sustaining treatment does not e x t e n d to artificial hydration and nutrition because they consider it to be basic Received from the Division of Gerontology and Geriatric Medicine, Department of Medicine (SM von P-F, RFU), and the Department of Biostatistics (KCC), University of Washington, Seattle, Washington. Supported by grants from the Hartford and Dana Foundations and by National Institute on Aging Academic Award number K08 AG00265 (Dr. Uhlmann). Address correspondence and reprint requests to Dr. Uhlmann: Harborview Medical Center, 325 9th Avenue, Seattle, WA 98104.
46
h u m a n care and not a medical intervention. 2-6 In addition, other factors such as life expectancy, quality of life, health care costs, and liability concerns may influence these decisions. 79 Concerns regarding artificial hydration and nutrition are particularly germane to nursing homes, given the high f r e q u e n c y of undernutrition in such settings. Indeed, m a n y nursing h o m e patients n o w stipulate their preferences for such treatment in advance. Thus, the degree to w h i c h patient preferences for artificial hydration and nutrition are r e s p e c t e d is especially important for nursing h o m e residents. We c o n d u c t e d a questionnaire-based, mailed survey of a national sample of physicians to d e t e r m i n e their attitudes toward t u b e feeding of nursing h o m e residents. O u r first study goal was to investigate w h e t h e r physicians thought it was ever justified to w i t h h o l d or w i t h d r a w artificial hydration and nutrition from nursing h o m e patients. Our second goal was to study the influences of patient preferences and other patient and physician factors on the tube feeding decisions.
METHODS Subjects To survey physicians w h o w e r e likely to p r o v i d e p r i m a r y care to nursing h o m e patients, w e r a n d o m l y selected 180 m e m b e r s of the American Medical Association (AMA) (60 each of general practitioners, family practitioners, and internists), as well as 167 physician m e m b e r s of the American Geriatrics Society (AGS). In April, 1989 physicians w e r e sent a packet containing a cover letter, a questionnaire, and a return envelope. The c o v e r letter did not state any hypothesis regarding the study. Physicians w h o did not respond to the initial mailing w e r e sent two follow-up mailings at threew e e k intervals. O f all physicians a p p r o a c h e d , 141 (41%) agreed to participate. The response rates w e r e 29% ( n = 52) from the AMA m e m b e r s and 53% ( n ----89) from the AGS m e m b e r s . To d e t e r m i n e w h e t h e r n o n r e s p o n d e n t s p r o v i d e d p r i m a r y care to nursing h o m e s residents, w e also c o n d u c t e d t e l e p h o n e interviews w i t h a r a n d o m 20% sample of n o n r e s p o n d e n t s from each g r o u p ( n = 23), and 12 of these physicians (52%) stated they did so, as c o m p a r e d w i t h 68% of responding physicians (Table 1).
JOURNALOF GENERALINTERNALMEDICINE, Volume 7 (January/February), 1992
The study was a p p r o v e d b y the H u m a n Subjects Review C o m m i t t e e of the University of Washington, Seattle, Washington.
Instruments and Data Collection The mailed questionnaire had three sections. The first section tested the influence of patient-related factors on tube feeding decisions through case scenarios. In the second section, physicians w e r e presented w i t h direct questions regarding the i m p o r t a n c e s of cost and legal considerations on tube feeding decisions. In the third section, information was elicited regarding physician d e m o g r a p h i c status and practice characteristics. In the first section, the influences of six patient factors (patient and family preferences, physical and cognitive function, age, and life e x p e c t a n c y ) on tube feeding decisions w e r e tested with hypothetical case scenarios using a fractional factorial design. In this design, a physician's strategy is inferred f r o m his or her decisions o v e r a series of cases w h e r e the status of factors influencing the decision is known. 1° Factorial design has b e e n used to evaluate medical decision making and s h o w n to predict actual practice b e h a v i o r for medical decisions. 1~ Each patient-related factor was presented at one of two possible levels (level O/level 1) in each of the scenarios. A literature survey was c o n d u c t e d to choose factors that have b e e n s h o w n to influence end-of-life decision making. Further, a research confere n c e and pretest w e r e c o n d u c t e d a m o n g colleagues w h o specialize in geriatric m e d i c i n e to o p t i m i z e the a d e q u a c y o f the levels chosen. The factor levels were: for/against tube feeding (patient preferences); f o r / against t u b e feeding (family preferences); not dem e n t e d / d e m e n t e d (cognitive function); Katz Activity of Daily Living (ADL) Scale 12 grade C: d e p e n d e n t in bathing and dressing/grade G: d e p e n d e n t in feeding, continence, transferring, toileting, dressing, bathing (physical function); life e x p e c t a n c y > 4 y e a r s / < l year; and age 69 y e a r s / 8 6 years. In order to decrease r e s p o n d e n t b u r d e n and enhance response rates, a fractional factorial design was used. Of the 64 possible scenarios that c o u l d be constructed, a previously described fractional m e t h o d was used to decrease the n u m b e r of scenarios to 16 (Table 2) x3, ~4 With this design, it is possible to estimate all the main effects of the factors examined. The 16-scenario fractional factorial design was used to generate clinically meaningful cases. Physicians w e r e initially p r e s e n t e d with the case of an elderly female nursing h o m e patient w i t h inadequate oral intake w h o was readmitted to a nursing h o m e following hospitalization for p n e u m o n i a . It was further described that medical and psychiatric evaluation failed to reveal an organic or psychiatric cause for her p o o r intake and that she was e x p e c t e d to die of malnutrition unless artificial means of n o u r i s h m e n t w e r e pro-
47
vided. After this general introduction, each case was then specific according to the case construction of the fractional factorial design. Patients w h o w e r e described as d e m e n t e d had b e e n diagnosed with Alzheimer's disease and had expressed p r e f e r e n c e s about artificial hydration and nutrition two years before the onset of their dementia. Since not all states have living will legislation, 15 it was stated that these preferences had b e e n made verbally in advance b y patients to their physicians, w i t h written medical record documentation. Physicians w e r e then asked to make two decisions for each case: 1) w h e t h e r they w o u l d initiate t u b e feeding and 2) w h e t h e r they w o u l d c o n t i n u e it if the patient's intake r e m a i n e d inadequate after four w e e k s of tube feeding. For the second decision, physicians w e r e asked to assume that the patient was initially p l a c e d on tube feeding (i.e., even if the physician had indicated they w o u l d have initially w i t h h e l d tube feeding). Physicians w e r e instructed to indicate the likelihood that they w o u l d tube feed on a five-point Likert scale (1 = definitely yes, 2 = p r o b a b l y yes, 3 ----unsure, 4 = p r o b a b l y not, and 5 = definitely not). To avoid influencing physicians' decisions by the order in w h i c h cases w e r e presented, w e created three different versions of this section, in w h i c h the same cases w e r e presented in different, r a n d o m l y selected orders. The three versions of the questionnaire w e r e distributed r a n d o m l y a m o n g physicians. Legal and cost considerations, w h i c h w e r e tested in the second section, w e r e not included as factors in the fractional factorial design because this w o u l d have resulted in an u n w i e l d y n u m b e r of scenarios. The legal and cost considerations that physicians w e r e asked to rate included potential legal liability, recent judicial decisions, medical care costs to society, and medical care costs to the patient's family. Physicians rated the i m p o r t a n c e s of these considerations on a linear, integer scale ranging from 0 (not important) to 1 O0 (decisively important). Physicians p r o v i d e d information about their dem o g r a p h i c status, professional training, and practice characteristics, including specialties and w h e t h e r they practiced in nursing homes.
Data Analysis The influence of each of the six factors was measured as the main effect of that factor, expressed as the change in Likert scale points as the level of a factor varied f r o m 0 to 1. The main effect of a factor was calculated as follows: The sum of the Likert scale scores for scenarios at level 0 was subtracted from the sum of the scores for scenarios at level 1 and the result divided b y 8. Since higher values on this scale indicate a red u c e d willingness to t u b e feed, positive values of this main effect indicate less willingness to t u b e feed at level 1 than at level O. The score change associated with
48
yon Preyss-Friedman et al., TuBe F ~ - ~
TABLE 1 PhysicianCharacteristics Society Membership AMA* (n=52)
AGSt (n=89)
Total (n=141)
Age--mean_ SD
4 8 + 14 years
48--- 13 years
48_+ 13 years
Gender-- female
10%
21%
17%
Specialty Generalpractice Family practice Internal medicine Other Geriatrics
10% 56% 30% 4% 8%
3% 40°,0 36% 2 I% 52%
8% 46% 34% 15% 36%
p < 0.001
Nursing home practice
56%
74%
68%
p < 0.05
p < 0.02
D¢CtS~NS
One-sample t-tests were used to determine w h e t h e r the mean of each main effect was significantly different from zero. Paired t-tests were used to compare the main effects for different factors. Relationships between physician characteristics and factor effects w e r e tested using linear regression, t-tests, and one-way ANOVA. Associations of legal and cost concerns to patientrelated factors and tube feeding decisions were tested with linear regression, one-way ANOVA, and Kendall's tau for nonparametric variables. Mean values ( + standard deviation) are reported.
RESULTS Physician Characteristics
*American MedicalAssociation. tAmerican Geriatrics Society.
the factor is a measure of absolute importance of the factor for an individual. We also calculated a measure of relative importance, defined as the ratio of the score change for one factor divided by the sum of the absolute values of the score change for all six factors. 1°, 16 T e s t - retest reliability for the factor effects was determined through a pretest in w h i c h the questionnaire was answered at a two-week interval by a group of 12 physicians w h o were not participants in the study. T e s t - r e t e s t reliability (kappa) was 0.95 (95% confidence interval, 0.70, 0.98) for patient preferences, 0.75 (95% CI, 0.31, 0.93) for families' preferences, and 0.74 (95% CI, 0.29, 0.92) for cognitive status. T e s t - retest reliability was less than 0.5 for the remaining factors (age, prognosis, and functional status).
TABLE Z Frequencyof Physicians' Decisionsto Limit Tube Feeding Number (%) of Physicians Number of scenariosin which tube feeding not initiated* 0/16 scenarios 1 - 4/16 scenarios 5 - 8/16 scenarios 9 - 12/16 scenarios 13- 15/16 scenarios 16/16 scenarios
6 (4.4) 30 (21.9) 67 (48.9) 32 (23.4) 1 (0.7) 1 (0.7)
Number of scenariosin which tube feeding not continued* O/16 scenarios 1 - 4 / 1 6 scenarios 5 - 8/16 scenarios 9 - 12/16 scenarios 13- 15/16 scenarios 16/16 scenarios
10 (7.6) 14 (10.7) 51 (38.9) 48 (36.6) 7 (5.3) 1 (0.7)
*" Definitely not" or "probably not" response.
The average age of responding physicians was 48 years, and most were men (Table 1). The largest proportion were in family practice, followed by internal medicine. About a third of the physicians considered themselves to be geriatricians, AGS members significantly more often than AMA members. The AGS sample was more heavily weighted toward internal medicine and other specialties, while the AMA sample was more heavily weighted toward family practice and general practice. Sixty-eight percent of the physicians cared for patients in nursing homes. Tube Feeding Decisions
Nearly all physicians indicated they w o u l d limit tube feeding in at least one of the 16 scenarios (Table 2). Only one physician never initiated or c o n t i n u e d tube feeding. Physicians were slightly but significantly more likely to initiate tube feeding (mean Likert scale score = 2.9) than to continue it (mean Likert scale score = 3.1) (p < 0.001).
Influences o f Patients' Preferences, Families' Preferences, and Other Patient Characteristics. Patients' preferences were the most important factor in physicians' decisions regarding initiating tube feeding. Whether or not a patient favored tube feeding resulted in a mean scale change of 1.7 (Table 3). Families' preferences were the second most important factor, associated with a mean scale change of 1.2. Life e x p e c t a n c y and cognitive status were also significantly associated with tube feeding decisions, although the changes in scale values were relatively small. Age and physical function were not significantly associated with the decisions. The influences of these factors on decisions to continue tube feeding were generally similar to those for decisions to initiate tube feeding e x c e p t that cognitive status (mean scale change = 0.42 + 0.6) was significantly more influential (p < 0.001). The average relative weights of the factors w e r e 41% for patient preferences, 29% for family prefer-
JOURNALOFGENERALINTERNALMEDICINE, Volume 7 (January/February). 1992
ences, 4% for life expectancy, 3% for cognitive status, and less than196 for functional status and age. Another way of looking at the results is to evaluate w h i c h one of the factors was most important overall for the individual decision maker. For most physicians (63%), patient preferences were ranked as most important, followed by family preferences, w h i c h 19% of physicians ranked as most important. Fourteen percent of physicians ranked both patient and family preferences as most important. Only a minority o f physicians (4%) ranked neither one of those factors first. We also analyzed w h e t h e r physicians honored patients' preferences w h e n families did not c o n c u r with the patients' preferences. When families and patients agreed, physicians decided in accordance with patients' preferences in 87% to 95% of the decisions and against them in 4% to 8% of the decisions (Table 4). However, w h e n patients and families disagreed, physicians decided in accordance with patients' preferences in only 48% to 55% of decisions, and against them in 29% to 37% o f the decisions.
Influences o f Cost and Legal C o n s i d e r a t i o n s . Legal concerns were considered somewhat more influential than cost concerns in decisions regarding tube feeding (Table 5). Increasing legal and liability concerns were significantly associated with higher likelihoods of initiating tube feeding in the 16 decisions ( t a u = - - 0 . 1 8 , p = < 0 . 0 1 ; tau ------ 0.19, p < 0.01, respectively). In contrast, increasing concerns regarding health care costs to society and to families were significantly associated with lower likelihoods of initiating tube feeding (tau = 0.23, p < 0.001; tau = 0.12, p < 0.05, respectively). We evaluated w h e t h e r legal or liability concerns c o u l d explain the influence of families' preferences on decisions to initiate tube feeding. The correlation of these concerns with families' preferences did not approach statistical significance. However, the tube feeding decisions of physicians w h o scored their legal concerns "1 O0 ----decisively important" ( n = 16) w e r e somewhat more influenced by families' preferences than were the decisions of other physicians (mean scale scores for family preferences, 1.6 ( + 1 . 0 ) and 1.2 ( + 0 . 7 ) , respectively, p----0.1). Physicians with the highest liability concerns ( n = 28) were not more influenced by families' preferences than were other physicians. Influences of Physician C h a r a c t e r i s t i c s . Physicians w h o practice in nursing homes were slightly but significantly less likely to order tube feeding than were physicians w h o do not practice in nursing homes (mean scale scores 3.2 and 2.9, respectively, p = 0 . 0 0 8 ) . Nursing h o m e physicians were also more influenced by patients' preferences (mean scale change for patient preferences 1.8 and 1.4, respectively, p < 0.02). Otherwise no significant difference was noted
49
between physicians w h o practice in nursing homes and those w h o do not. Older physicians were less influenced by patients' preferences than were younger physicians (r = --O. 3, p = 0.001). In addition, general practitioners were less likely to be influenced by patients' preferences than were other specialists (p < 0.05). Other physician characteristics, including gender and geriatrics specialization, were not significantly associated with the treatment decisions.
TABLE 3 Influence of Factors on the Decisions to Initiate Tube Feeding Scale* Change Mean
(-----SD) Associated with Factor Patient's preference Family's preference Life expectancy Cognitive status Physical function Age *1= not, and 5 tp < *p
Participants: R a n d o m l y selected n a t t o n a l samples o f American Geriatrics Society a n d A m e r i c a n Medical Associatton m e m b e r s ( n = 141, p a r t i c i p a t i o n rate 41%).
Main results: Nearly all p h y s i c i a n s indicated they w o u l d w i t h h o l d (95%) o r w i t h d r a w (92%) tube f e e d i n g in a t least o n e o f the 16 s c e n a r i o s studied. P h y s i c i a n decisions were m o s t highly associated with p a t i e n t preferences, f o l l o w e d by f a m i l y preferences, life expectancy, a n d cognitive status ( p < 0.02 to < 0.001). When p a t i e n t s a n d f a m i l i e s agreed, p h y s i c i a n s c o n c u r r e d in 87% to 95% o f the decisions. However, w h e n p a t i e n t s a n d f a m i l i e s disagreed, p h y s i c i a n s c o n c u r r e d with p a t i e n t s in only 48% to 55% o f the decisions. I n c r e a s i n g p h y s i c i a n c o n c e r n r e g a r d i n g legal a n d cost c o n s i d e r a t i o n s was significantly associated with significantly h i g h e r a n d l o w e r likelihoods o f tube f e e d i n ~ respectively ( p < 0.05). Conclusions: These results suggest that the m a j o r i t y o f study p h y s i c i a n s a r e willing to limit tube f e e d i n g in nursing h o m e p a t l e n t s u n d e r some circtanstances. P a t t e n t p r e f erences a p p e a r to be the m o s t i m p o r t a n t f a c t o r i n these decisions, but m a y n o t be honored, especially i f the wishes o f p a t i e n t s a n d their f a m i l i e s a r e n o t in concurrence. Key words: aging, attitudes; decision making, n u r s i n g homes; tube f e e d i n g , medicolegaL J GEN INTERN MED 1992;7:46- 51.
THE LIMITATIONOF artificial hydration and nutrition is
one of the most controversial issues in medicine. Patients are generally considered to have the right to refuse life-sustaining treatment. ~ However, the influe n c e of patients' preferences for artificial hydration and nutrition on physicians' decision making is unclear. For e x a m p l e , some physicians and long-term care institutions believe that the right to refuse life-sustaining treatment does not e x t e n d to artificial hydration and nutrition because they consider it to be basic Received from the Division of Gerontology and Geriatric Medicine, Department of Medicine (SM von P-F, RFU), and the Department of Biostatistics (KCC), University of Washington, Seattle, Washington. Supported by grants from the Hartford and Dana Foundations and by National Institute on Aging Academic Award number K08 AG00265 (Dr. Uhlmann). Address correspondence and reprint requests to Dr. Uhlmann: Harborview Medical Center, 325 9th Avenue, Seattle, WA 98104.
46
h u m a n care and not a medical intervention. 2-6 In addition, other factors such as life expectancy, quality of life, health care costs, and liability concerns may influence these decisions. 79 Concerns regarding artificial hydration and nutrition are particularly germane to nursing homes, given the high f r e q u e n c y of undernutrition in such settings. Indeed, m a n y nursing h o m e patients n o w stipulate their preferences for such treatment in advance. Thus, the degree to w h i c h patient preferences for artificial hydration and nutrition are r e s p e c t e d is especially important for nursing h o m e residents. We c o n d u c t e d a questionnaire-based, mailed survey of a national sample of physicians to d e t e r m i n e their attitudes toward t u b e feeding of nursing h o m e residents. O u r first study goal was to investigate w h e t h e r physicians thought it was ever justified to w i t h h o l d or w i t h d r a w artificial hydration and nutrition from nursing h o m e patients. Our second goal was to study the influences of patient preferences and other patient and physician factors on the tube feeding decisions.
METHODS Subjects To survey physicians w h o w e r e likely to p r o v i d e p r i m a r y care to nursing h o m e patients, w e r a n d o m l y selected 180 m e m b e r s of the American Medical Association (AMA) (60 each of general practitioners, family practitioners, and internists), as well as 167 physician m e m b e r s of the American Geriatrics Society (AGS). In April, 1989 physicians w e r e sent a packet containing a cover letter, a questionnaire, and a return envelope. The c o v e r letter did not state any hypothesis regarding the study. Physicians w h o did not respond to the initial mailing w e r e sent two follow-up mailings at threew e e k intervals. O f all physicians a p p r o a c h e d , 141 (41%) agreed to participate. The response rates w e r e 29% ( n = 52) from the AMA m e m b e r s and 53% ( n ----89) from the AGS m e m b e r s . To d e t e r m i n e w h e t h e r n o n r e s p o n d e n t s p r o v i d e d p r i m a r y care to nursing h o m e s residents, w e also c o n d u c t e d t e l e p h o n e interviews w i t h a r a n d o m 20% sample of n o n r e s p o n d e n t s from each g r o u p ( n = 23), and 12 of these physicians (52%) stated they did so, as c o m p a r e d w i t h 68% of responding physicians (Table 1).
JOURNALOF GENERALINTERNALMEDICINE, Volume 7 (January/February), 1992
The study was a p p r o v e d b y the H u m a n Subjects Review C o m m i t t e e of the University of Washington, Seattle, Washington.
Instruments and Data Collection The mailed questionnaire had three sections. The first section tested the influence of patient-related factors on tube feeding decisions through case scenarios. In the second section, physicians w e r e presented w i t h direct questions regarding the i m p o r t a n c e s of cost and legal considerations on tube feeding decisions. In the third section, information was elicited regarding physician d e m o g r a p h i c status and practice characteristics. In the first section, the influences of six patient factors (patient and family preferences, physical and cognitive function, age, and life e x p e c t a n c y ) on tube feeding decisions w e r e tested with hypothetical case scenarios using a fractional factorial design. In this design, a physician's strategy is inferred f r o m his or her decisions o v e r a series of cases w h e r e the status of factors influencing the decision is known. 1° Factorial design has b e e n used to evaluate medical decision making and s h o w n to predict actual practice b e h a v i o r for medical decisions. 1~ Each patient-related factor was presented at one of two possible levels (level O/level 1) in each of the scenarios. A literature survey was c o n d u c t e d to choose factors that have b e e n s h o w n to influence end-of-life decision making. Further, a research confere n c e and pretest w e r e c o n d u c t e d a m o n g colleagues w h o specialize in geriatric m e d i c i n e to o p t i m i z e the a d e q u a c y o f the levels chosen. The factor levels were: for/against tube feeding (patient preferences); f o r / against t u b e feeding (family preferences); not dem e n t e d / d e m e n t e d (cognitive function); Katz Activity of Daily Living (ADL) Scale 12 grade C: d e p e n d e n t in bathing and dressing/grade G: d e p e n d e n t in feeding, continence, transferring, toileting, dressing, bathing (physical function); life e x p e c t a n c y > 4 y e a r s / < l year; and age 69 y e a r s / 8 6 years. In order to decrease r e s p o n d e n t b u r d e n and enhance response rates, a fractional factorial design was used. Of the 64 possible scenarios that c o u l d be constructed, a previously described fractional m e t h o d was used to decrease the n u m b e r of scenarios to 16 (Table 2) x3, ~4 With this design, it is possible to estimate all the main effects of the factors examined. The 16-scenario fractional factorial design was used to generate clinically meaningful cases. Physicians w e r e initially p r e s e n t e d with the case of an elderly female nursing h o m e patient w i t h inadequate oral intake w h o was readmitted to a nursing h o m e following hospitalization for p n e u m o n i a . It was further described that medical and psychiatric evaluation failed to reveal an organic or psychiatric cause for her p o o r intake and that she was e x p e c t e d to die of malnutrition unless artificial means of n o u r i s h m e n t w e r e pro-
47
vided. After this general introduction, each case was then specific according to the case construction of the fractional factorial design. Patients w h o w e r e described as d e m e n t e d had b e e n diagnosed with Alzheimer's disease and had expressed p r e f e r e n c e s about artificial hydration and nutrition two years before the onset of their dementia. Since not all states have living will legislation, 15 it was stated that these preferences had b e e n made verbally in advance b y patients to their physicians, w i t h written medical record documentation. Physicians w e r e then asked to make two decisions for each case: 1) w h e t h e r they w o u l d initiate t u b e feeding and 2) w h e t h e r they w o u l d c o n t i n u e it if the patient's intake r e m a i n e d inadequate after four w e e k s of tube feeding. For the second decision, physicians w e r e asked to assume that the patient was initially p l a c e d on tube feeding (i.e., even if the physician had indicated they w o u l d have initially w i t h h e l d tube feeding). Physicians w e r e instructed to indicate the likelihood that they w o u l d tube feed on a five-point Likert scale (1 = definitely yes, 2 = p r o b a b l y yes, 3 ----unsure, 4 = p r o b a b l y not, and 5 = definitely not). To avoid influencing physicians' decisions by the order in w h i c h cases w e r e presented, w e created three different versions of this section, in w h i c h the same cases w e r e presented in different, r a n d o m l y selected orders. The three versions of the questionnaire w e r e distributed r a n d o m l y a m o n g physicians. Legal and cost considerations, w h i c h w e r e tested in the second section, w e r e not included as factors in the fractional factorial design because this w o u l d have resulted in an u n w i e l d y n u m b e r of scenarios. The legal and cost considerations that physicians w e r e asked to rate included potential legal liability, recent judicial decisions, medical care costs to society, and medical care costs to the patient's family. Physicians rated the i m p o r t a n c e s of these considerations on a linear, integer scale ranging from 0 (not important) to 1 O0 (decisively important). Physicians p r o v i d e d information about their dem o g r a p h i c status, professional training, and practice characteristics, including specialties and w h e t h e r they practiced in nursing homes.
Data Analysis The influence of each of the six factors was measured as the main effect of that factor, expressed as the change in Likert scale points as the level of a factor varied f r o m 0 to 1. The main effect of a factor was calculated as follows: The sum of the Likert scale scores for scenarios at level 0 was subtracted from the sum of the scores for scenarios at level 1 and the result divided b y 8. Since higher values on this scale indicate a red u c e d willingness to t u b e feed, positive values of this main effect indicate less willingness to t u b e feed at level 1 than at level O. The score change associated with
48
yon Preyss-Friedman et al., TuBe F ~ - ~
TABLE 1 PhysicianCharacteristics Society Membership AMA* (n=52)
AGSt (n=89)
Total (n=141)
Age--mean_ SD
4 8 + 14 years
48--- 13 years
48_+ 13 years
Gender-- female
10%
21%
17%
Specialty Generalpractice Family practice Internal medicine Other Geriatrics
10% 56% 30% 4% 8%
3% 40°,0 36% 2 I% 52%
8% 46% 34% 15% 36%
p < 0.001
Nursing home practice
56%
74%
68%
p < 0.05
p < 0.02
D¢CtS~NS
One-sample t-tests were used to determine w h e t h e r the mean of each main effect was significantly different from zero. Paired t-tests were used to compare the main effects for different factors. Relationships between physician characteristics and factor effects w e r e tested using linear regression, t-tests, and one-way ANOVA. Associations of legal and cost concerns to patientrelated factors and tube feeding decisions were tested with linear regression, one-way ANOVA, and Kendall's tau for nonparametric variables. Mean values ( + standard deviation) are reported.
RESULTS Physician Characteristics
*American MedicalAssociation. tAmerican Geriatrics Society.
the factor is a measure of absolute importance of the factor for an individual. We also calculated a measure of relative importance, defined as the ratio of the score change for one factor divided by the sum of the absolute values of the score change for all six factors. 1°, 16 T e s t - retest reliability for the factor effects was determined through a pretest in w h i c h the questionnaire was answered at a two-week interval by a group of 12 physicians w h o were not participants in the study. T e s t - r e t e s t reliability (kappa) was 0.95 (95% confidence interval, 0.70, 0.98) for patient preferences, 0.75 (95% CI, 0.31, 0.93) for families' preferences, and 0.74 (95% CI, 0.29, 0.92) for cognitive status. T e s t - retest reliability was less than 0.5 for the remaining factors (age, prognosis, and functional status).
TABLE Z Frequencyof Physicians' Decisionsto Limit Tube Feeding Number (%) of Physicians Number of scenariosin which tube feeding not initiated* 0/16 scenarios 1 - 4/16 scenarios 5 - 8/16 scenarios 9 - 12/16 scenarios 13- 15/16 scenarios 16/16 scenarios
6 (4.4) 30 (21.9) 67 (48.9) 32 (23.4) 1 (0.7) 1 (0.7)
Number of scenariosin which tube feeding not continued* O/16 scenarios 1 - 4 / 1 6 scenarios 5 - 8/16 scenarios 9 - 12/16 scenarios 13- 15/16 scenarios 16/16 scenarios
10 (7.6) 14 (10.7) 51 (38.9) 48 (36.6) 7 (5.3) 1 (0.7)
*" Definitely not" or "probably not" response.
The average age of responding physicians was 48 years, and most were men (Table 1). The largest proportion were in family practice, followed by internal medicine. About a third of the physicians considered themselves to be geriatricians, AGS members significantly more often than AMA members. The AGS sample was more heavily weighted toward internal medicine and other specialties, while the AMA sample was more heavily weighted toward family practice and general practice. Sixty-eight percent of the physicians cared for patients in nursing homes. Tube Feeding Decisions
Nearly all physicians indicated they w o u l d limit tube feeding in at least one of the 16 scenarios (Table 2). Only one physician never initiated or c o n t i n u e d tube feeding. Physicians were slightly but significantly more likely to initiate tube feeding (mean Likert scale score = 2.9) than to continue it (mean Likert scale score = 3.1) (p < 0.001).
Influences o f Patients' Preferences, Families' Preferences, and Other Patient Characteristics. Patients' preferences were the most important factor in physicians' decisions regarding initiating tube feeding. Whether or not a patient favored tube feeding resulted in a mean scale change of 1.7 (Table 3). Families' preferences were the second most important factor, associated with a mean scale change of 1.2. Life e x p e c t a n c y and cognitive status were also significantly associated with tube feeding decisions, although the changes in scale values were relatively small. Age and physical function were not significantly associated with the decisions. The influences of these factors on decisions to continue tube feeding were generally similar to those for decisions to initiate tube feeding e x c e p t that cognitive status (mean scale change = 0.42 + 0.6) was significantly more influential (p < 0.001). The average relative weights of the factors w e r e 41% for patient preferences, 29% for family prefer-
JOURNALOFGENERALINTERNALMEDICINE, Volume 7 (January/February). 1992
ences, 4% for life expectancy, 3% for cognitive status, and less than196 for functional status and age. Another way of looking at the results is to evaluate w h i c h one of the factors was most important overall for the individual decision maker. For most physicians (63%), patient preferences were ranked as most important, followed by family preferences, w h i c h 19% of physicians ranked as most important. Fourteen percent of physicians ranked both patient and family preferences as most important. Only a minority o f physicians (4%) ranked neither one of those factors first. We also analyzed w h e t h e r physicians honored patients' preferences w h e n families did not c o n c u r with the patients' preferences. When families and patients agreed, physicians decided in accordance with patients' preferences in 87% to 95% of the decisions and against them in 4% to 8% of the decisions (Table 4). However, w h e n patients and families disagreed, physicians decided in accordance with patients' preferences in only 48% to 55% of decisions, and against them in 29% to 37% o f the decisions.
Influences o f Cost and Legal C o n s i d e r a t i o n s . Legal concerns were considered somewhat more influential than cost concerns in decisions regarding tube feeding (Table 5). Increasing legal and liability concerns were significantly associated with higher likelihoods of initiating tube feeding in the 16 decisions ( t a u = - - 0 . 1 8 , p = < 0 . 0 1 ; tau ------ 0.19, p < 0.01, respectively). In contrast, increasing concerns regarding health care costs to society and to families were significantly associated with lower likelihoods of initiating tube feeding (tau = 0.23, p < 0.001; tau = 0.12, p < 0.05, respectively). We evaluated w h e t h e r legal or liability concerns c o u l d explain the influence of families' preferences on decisions to initiate tube feeding. The correlation of these concerns with families' preferences did not approach statistical significance. However, the tube feeding decisions of physicians w h o scored their legal concerns "1 O0 ----decisively important" ( n = 16) w e r e somewhat more influenced by families' preferences than were the decisions of other physicians (mean scale scores for family preferences, 1.6 ( + 1 . 0 ) and 1.2 ( + 0 . 7 ) , respectively, p----0.1). Physicians with the highest liability concerns ( n = 28) were not more influenced by families' preferences than were other physicians. Influences of Physician C h a r a c t e r i s t i c s . Physicians w h o practice in nursing homes were slightly but significantly less likely to order tube feeding than were physicians w h o do not practice in nursing homes (mean scale scores 3.2 and 2.9, respectively, p = 0 . 0 0 8 ) . Nursing h o m e physicians were also more influenced by patients' preferences (mean scale change for patient preferences 1.8 and 1.4, respectively, p < 0.02). Otherwise no significant difference was noted
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between physicians w h o practice in nursing homes and those w h o do not. Older physicians were less influenced by patients' preferences than were younger physicians (r = --O. 3, p = 0.001). In addition, general practitioners were less likely to be influenced by patients' preferences than were other specialists (p < 0.05). Other physician characteristics, including gender and geriatrics specialization, were not significantly associated with the treatment decisions.
TABLE 3 Influence of Factors on the Decisions to Initiate Tube Feeding Scale* Change Mean
(-----SD) Associated with Factor Patient's preference Family's preference Life expectancy Cognitive status Physical function Age *1= not, and 5 tp < *p
