Comparing Hospice and Nonhospice Patient Survival Among Patients Who Die Within a Three-Year Window

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1 238 Journal of Pain an Symptom Management Vol. 33 No. 3 Marh 2007 NHPCO Original Artile Comparing Hospie an Nonhospie Patient Survival Among Patients Who Die Within a Three-Year Winow Stephen R. Connor, PhD, Brue Pyenson, FSA, MAAA, Kathryn Fith, RN, MA, ME, Carol Spene, RN, MS, an Kosuke Iwasaki, FIAJ, MAAA National Hospie an Palliative Care Organization (S.R.C., C.S.), Alexanria, Virginia; an Milliman, In. (B.P., K.F., K.I.), New York, New York, USA Abstrat There is a wiesprea belief by some health are proviers an the wier ommunity that meiations use to alleviate symptoms may hasten eath in hospie patients. Conversely, there is a linial impression among hospie proviers that hospie might exten some patients lives. We stuie the ifferene of survival perios of terminally ill patients between those using hospies an not using hospies. We performe retrospetive statistial analysis on selete ohorts from large pai laim atabases of Meiare benefiiaries for five types of aner an ongestive heart failure (CHF) patients. We analyze the survival of 4493 patients from a sample of 5% of the entire Meiare benefiiary population for 1998e2002 assoiate with six narrowly efine iniative markers. For the six patient populations ombine, the mean survival was 29 ays longer for hospie patients than for nonhospie patients. The mean survival perio was also signifiantly longer for the hospie patients with CHF, lung aner, panreati aner, an marginally signifiant for olon aner (P ¼ 0.08). Mean survival was not signifiantly ifferent (statistially) for hospie vs. nonhospie patients with breast or prostate aner. Aross groups stuie, hospie enrollment is not signifiantly assoiate with shorter survival, but for ertain terminally ill patients, hospie is assoiate with longer survival times. The laims-base metho use eath within three years as a surrogate for a linial jugment to reommen hospie, whih means our finings apply to ases where a liniian is very sure the patient will ie within three years, an it points to the nee to valiate these finings. J Pain Symptom Manage 2007;33:238e246. Ó 2007 U.S. Caner Pain Relief Committee. Publishe by Elsevier In. All rights reserve. Key Wors Survival, hospie, palliative are, aner, ongestive heart failure This stuy was sponsore by the National Hospie an Palliative Care Organization. Aress reprint requests to: Stephen R. Connor, PhD, National Hospie an Palliative Care Organization, 1700 Diagonal Roa, Suite 625, Alexanria, VA 22314, USA. sonnor@nhpo.org Aepte for publiation: Otober 13, Ó 2007 U.S. Caner Pain Relief Committee Publishe by Elsevier In. All rights reserve. Introution The purpose of hospie is to effetively provie palliative are to terminally ill patients an their families, whih inlues meeting patients physial, soial, spiritual, an emotional nees. The goal of hospie is neither to prolong life nor to hasten the ying proess, but /07/$esee front matter oi: /j.jpainsymman

2 Vol. 33 No. 3 Marh 2007 Survival of Hospie Patients 239 rather is to maximize patients quality of life as they travel along this last journey. However, there is a pereption among some health are proviers that symptom ontrol in palliative are, espeially the use of opiois an seatives, may ause patients to ie sooner than they woul otherwise. Conversely, preliminary eviene has suggeste that the lives of some patients might atually be extene through the use of hospie are. 1e4 There is a growing boy of eviene to ounter the argument that the use of opioi an seative meiations for symptom relief hastens eath, 5e9 even in patients who are reeiving high oses of morphine an other opiois. 5,7 There have been few stuies publishe, however, that have evaluate the effet of hospie are on inreasing the longevity of terminally ill patients. In a stuy on the ost ifferenes between patients who o an who o not elet to reeive Meiare-pai hospie benefits, 10 we isovere that osts were lower for patients reeiving hospie are an that these osts were not assoiate with shorter time until eath. In fat, in this sample of 8700 patients rawn from the Meiare 5% sample atabase, the use of hospie appeare to be assoiate with longer time until eath. Beause ost was the fous of our original stuy, only patients who ie uring the twoyear stuy perio (i.e., 1999 an 2000) were inlue, whih limite the value of the ata for a survival stuy. The fat that patients who hose hospie showe longer mean an meian time until eath by ays to months for all 16 iagnosis ategories stuie prompte us to investigate our finings further. In the urrent stuy, we use a similar methoology to that esribe in our previous work; 10 however, we limite the ohorts to six that ha suffiient numbers for analysis an expane the stuy perio to inlue ata from 2001 an 2002 in aition to 1999 an 2000 to better measure the survival perio. Methos In this retrospetive ohort stuy, we use an innovative prospetive/retrospetive ase ontrol metho an Meiare aministrative ata to measure time until eath starting from ates that were narrowly efine within the ata. We performe a Kaplan-Meier analysis of the ohorts an use multiple regression moels to evaluate the ifferene of survival perios of terminal illness patients between those using hospies an those not using hospies. For eah isease ohort, a set of speifi linial events was use to efine an iniative event an a ate to measure the beginning point for time to eath. Soures of the Data From the Centers for Meiare an Meiai Servies, we use Meiare 5% sample ata in 1998, 1999, 2000, 2001, an This ata set ontains all Meiare-pai laims generate by a statistially representative sample of Meiare benefiiaries. Member ientifiation oes are onsistent from year to year an allow for multiyear longituinal stuies. Moreover, this information is generate for both inpatient an outpatient settings. Information inlues iagnosis oes, proeure oes, an iagnosis-relate group (DRG) oes, along with site of servie information, an the amounts pai by Meiare. We use ata from 1998 to 1999 to ientify ohort members an fin the iniative ates of the iagnostis assoiate with terminal illness. We use the 2000, 2001, an 2002 ata to measure the survival perios after the iniative ates. Aitional ata were obtaine from the Health Care Finaning Aministration Stanar Analyti File of Meiare 5% sample hospie laim ata in 1999, 2000, 2001, an 2002, whih ontain more etaile information on the hospie laims, inluing hospie start an en ates. Patient Cohorts Meiare benefiiaries were ientifie from 1999 laim ata if they met iniative marker riteria for any of the six iseases an ie within three years of the iniative marker ate. The restrition of the ata to people who ie within three years of the iniative marker was meant to be a surrogate for linial jugment, as laim ata are not a ompletely aurate preitor of terminal eline. Stritly speaking, this ata restrition means our results apply to ases where a liniian is very sure the patient will ie within three years.

3 240 Connor et al. Vol. 33 No. 3 Marh 2007 The iseases were ongestive heart failure (CHF), breast aner, olon aner, lung aner, prostate aner, an panreati aner. Patients were ientifie as having one of the six iseases if they ha at least one inpatient hospital laim or at least two Part B laims with ifferent servie ates with the following ICD-9 oes: CHF428 as the primary iagnosis oe; breast aner174.0e174.9 in any position of the laim; olon aner153.0e153.9 in any position of the laim; lung aner162.0e162.9 in any position of the laim; prostate aner185 in any position of the laim; an panreati aner157.0e157.9 in any position of the laim (exept 157.4, islet ell aner). Part B laims in the Current Proeural Terminology (CPT) 70,000 or 80,000 series or with Healthare Common Proeure Coing System (HCPCS) oes beginning with a letter were exlue to avoi potential false positive ientifiation through laboratory or raiology laims. Patients with more than one isease were assigne using the hierarhy: panreas, olon, lung, breast, prostate, an CHF. We inlue only patients who ha eligibility in 1998, an iniative ate in 1999 an who ie within three years after the iniative ate. We ha no information on whether any of the survivors beyon three years may have hosen hospie after three years. We exlue patients who ie within 15 ays after the iniative ate, as these patients woul have ha limite opportunity to partiipate in hospie. We performe a look bak to 1998 an exlue patients who ha an iniative ate in 1998 in an attempt to use the first iniative ate for eah ohort member. Patients were ivie into hospie an nonhospie ohorts. Patients inlue in the hospie group were those who ha at least one laim for hospie servies within three years after the iniative ate. The other patients were lassifie in the nonhospie group. Iniative Markers We hose iniative markers for the six iagnoses that ientifie a point in the isease progression uner whih a patient oul shortly thereafter be avise to onsier obtaining hospie are. A thorough esription of how these iniative markers were erive for eah iagnosis is presente in our earlier paper. 10 In brief, the iniative ate for eah patient was efine as the ate that iniate the beginning of the terminal stage of the isease. Any patient without an iniative ate was exlue from the stuy. For breast aner, the iniative ate was efine as the maximum ate that iniate a swith to another ombination of hemotherapy rugs within one to two quarters of the initial hemotherapy. Chemotherapy laims were efine as Part B laims having HCPCS oes of J9000eJ9999 (exept J9170, Doetaxel). A hemotherapy laim was onsiere a swithing hemotherapy laim if 1)the hemotherapy laim was for a ifferent lass of hemotherapy rug from the lass of the prior hemotherapy laim an 2) the swithing hemotherapeuti laim began uring the 1e180-ay interval after the prior hemotherapy laim. For olon aner, the iniative ate was efine for three senarios. First, if there were no olon resetion laim, then the iniative ate was the minimum ate of hemotherapy laims. Seon, if a hemotherapy laim ourre within one quarter of the olon resetion, then the iniative ate was the minimum ate of the hemotherapy laims. Thir, if the first an seon senario i not apply, then the iniative ate was the first ate of an intestinal stent laim. Colon resetion laims were ientifie by urrent proeural terminology (CPT) oes 44140e Chemotherapy laims were ientifie by CPT oes 96400e96549 an by HCPCS J9000eJ9999. Intestinal stent laims were ientifie by CPT oes 45327, 45345, an For lung aner, the iniative ate was efine as the last laim servie ate of swithing hemotherapy or biopsy followe by hemotherapy laims. The efinition of swithing hemotherapy was the same for lung aner as for breast aner, an the efinition of hemotherapy laims was also the same as for breast aner. The efinition for a biopsy followe by a hemotherapy laim ontaine three riteria: 1)the benefiiary ha a biopsy laim; 2)a hemotherapy laim followe the

4 Vol. 33 No. 3 Marh 2007 Survival of Hospie Patients 241 biopsy laim; an 3)the benefiiary ha no lung resetion laim. The biopsy laim was ientifie by CPT oes 32405, 10022, an The lung resetion laim was ientifie by CPT oes 32440, 32480, 32482, 32484, 32486, 32488, 32501, 32520, 32522, an For prostate aner, the iniative ate was efine as the minimum ate of strontium laims. Strontium laims were ientifie by a strontium 89 HCPCS oe of A9600. For panreati aner, the iniative ate was the minimum ate of laims having an ICD-9 of 157.0e157.9 (exept 157.4, islet ell aner). For CHF, the iniative ate was efine as the maximum ate of a ventilatory management laim when all of the following three riteria were met: there was no oronary artery bypass graft (CABG) laim in the same or next quarter; there was no myoarial infartion (MI) laim in the same quarter; an there was an inpatient laim with a primary iagnosis oe of 428 within the same quarter. A ventilatory management laim was ientifie by intubation an Ventilator Management CPT oes of 94656, 94657, an CABG laims were ientifie by CPT oes of an A MI laim was efine by the inpatient laim having MI ICD-9 in any position (i.e., aute MI ICD-9: 410.0e410.9). The hospie an nonhospie ohorts proue by eah olon aner iniative ate efinition ha similar istributions, as i the ohorts using the CHF iniative ates. Thus, there oes not appear to be a bias generate by the options within these iseases. We note that it is possible that the final hemo swithing approah we use for breast an lung aner may proue shorter survival for nonhospie ohorts if they reeive more hemo swithes after faile therapies. Statistial Analysis We analyze the ata using SASÔ statistial software (SAS Institute In., Cary, NC) an ExelÔ (Mirosoft Corporation, Remon, WA). The epenent variable in our analysis was the length of survival in ays. The survival perio was efine as the uration between the iniative ate an the ate of eath. The inepenent variables inlue the patient s iagnosis, age, sex, rae, an use of hospie. Gehan P values for the ifferene of the two survival urves weighte by the number of survivors were alulate to analyze the survival perios of hospie an nonhospie patients. This test was performe using SASÔ PROC LIFETEST. A multiple regression moel was use to etermine the fators that influene survival perios. We limite the moel to nine variables to minimize Mallow s C( p) statisti. The nine variables use in the moel were CHF, breast aner, olon aner, lung aner, panreati aner, age ategory 80e89 years, age ategory 90þ years, white, an use of hospie. A separate multiple regression moel was use to etermine the fators that influene survival ays for the hospie ohort. This moel was also limite to nine variables, whih were CHF, breast aner, olon aner, lung aner, panreati aner, age ategory 60e69 years, age ategory 70e79 years, Hispani status, an length of hospie stay. Results We ientifie 4493 patients who met our riteria for the six iseases. Of these patients, 2095 (47%) reeive hospie are for at least one ay. Table 1 summarizes harateristis Table 1 Desription of Stuy Population (Sample Size) Variable Hospie (n ¼ 2095) Nonhospie (n ¼ 2260) Disease CHF 83 (4%) 457 (20%) Breast aner 158 (8%) 136 (6%) Colon aner 337 (16%) 215 (10%) Lung aner 700 (33%) 586 (26%) Panreati aner 493 (24%) 386 (17%) Prostate aner 324 (15%) 480 (21%) Age (years) <60 72 (3%) 111 (5%) 60e (5%) 109 (5%) 65e (21%) 451 (20%) 70e (26%) 514 (23%) 75e (23%) 482 (21%) 80e (13%) 337 (15%) 85e (6%) 185 (8%) 90þ 45 (2%) 71 (3%) Mean age % Female Rae White 1860 (89%) 1897 (84%) Blak 167 (8%) 259 (11%) Hispani 24 (1%) 50 (2%) Asian 14 (1%) 15 (1%) Other 30 (1%) 39 (2%)

5 242 Connor et al. Vol. 33 No. 3 Marh 2007 of the patients. The most ommon iagnosis was lung aner for both the hospie ohort an nonhospie ohort (33% an 26%, respetively), an the least ommon iagnosis was breast aner (8% an 6%, respetively). The number of patients with olon, lung, an panreati aner was generally higher for the hospie ohort than the nonhospie ohort (a ifferene of 6%e7% between the ohorts for eah iagnosis). The number of patients with CHF was onsierably higher for the nonhospie ohort than for the hospie ohort (20% vs. 4%). The age groups were similar for both hospie an nonhospie ohorts, with a mean age of 74 years for both ohorts. Females aounte for 45% of the hospie ohort an 41% of the nonhospie ohort. Whites omprise the majority of the sample (89% an 84% in the hospie an nonhospie ohorts). For the hospie ohort, the mean length of stay in hospie was 43 ays but varie by ohort. Survival Perios For the entire sample of all isease ohorts, the mean number of survival ays was eight ays longer for hospie patients than for nonhospie patients (337 vs. 329 ays, P ¼ ). This ifferene inlues the effets of many fators inluing emographis an sample sizes of the two ohorts. When we normalize these other fators, the ifferene in ays inreases to 29 ays, as we show later in the regression. The survival perio was signifiantly longer for the hospie ohort than for the nonhospie ohort for the following iseases: CHF (402 vs. 321 ays, P ¼ ), lung aner (279 vs. 240 ays, P < ), an panreati aner (210 vs. 189 ays, P ¼ ). The survival perio was longer for the hospie ohort than nonhospie ohort for olon aner, an the ifferene approahe but i not reah statistial signifiane (414 vs. 381 ays, P ¼ ). Survival plots for CHF, lung aner, panreati aner, an olon aner are presente in Figs. 1e4. There was no statistially signifiant ifferene between the hospie an nonhospie ohorts for breast aner (422 vs. 410 ays, P ¼ ) or prostate aner (514 vs. 510 ays, P ¼ ). Regression Moels The seon regression was performe only for hospie ohorts to etermine the fators that influene survival ays, whih are presente in Table 2. The R square was 14.6%. The oeffiient of hospie was 29 ays, iniating that hospie patients live longer than patients not using hospie by 29 ays. The results of the regression for the hospie ohort are also presente in Table 3. In the moel, the oeffiient of length of hospie stay was 0.8. It is not self-evient that the longer hospie ays result in the longer survival ays, beause we efine the survival ays at the iniative ate. However, the results of the regression show that there is a positive orrelation between length of hospie stay an the survival ays. This result ombine with the oeffiient of 29 ays for the overall regression suggests that a hospie patient live longer by 0.8 times the number of ays in Perent Survivals 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Nonhospie Hospie Days after Iniative Date Fig. 1. Survival urve for patients with CHF.

6 Vol. 33 No. 3 Marh 2007 Survival of Hospie Patients % 90% Perent Survivals 80% 70% 60% 50% 40% 30% 20% 10% Nonhospie Hospie 0% Days after Iniative Date Fig. 2. Survival urve for patients with olon aner. hospie. The 0.8 oeffiient is lose to the overall hospie oeffiient (29 ays) ivie by the average length of hospie ays (43 ays) (29/ 43 ¼ 0.7). The positive parameter for the length of hospie stay in the regression moel suggests that hospie oes not shorten life. Disussion Although hospie aims neither to prolong life nor to hasten eath, there has been a linial pereption among hospie proviers that the use of hospie may atually prolong terminally ill patients lives, espite the fat that these patients have mae the eision to forego further urative treatment. Our finings suggest that hospie may inee have a positive impat on patients longevity or at least not hasten eath. We foun that for ertain well-efine terminally ill populations, patients who hoose hospie are live an average of 29 ays longer than similar patients who o not hoose hospie. This pattern persiste over four of the six isease ategories stuie, though there was substantial variation in the mean length of survival aoring to iagnosis. Of note, the largest ifferene in survival between the hospie an nonhospie ohort was for the CHF patients, where relatively few patients hose hospie are. CHF patients who eventually hose hospie ha a mean survival of 402 ays ompare with 321 ays for those who i not. Perent Survivals 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% Nonhospie Hospie 0% Days after Iniative Date Fig. 3. Survival urve for patients with lung aner.

7 244 Connor et al. Vol. 33 No. 3 Marh % 90% Perent Survivals 80% Nonhospie 70% Hospie 60% 50% 40% 30% 20% 10% 0% Days after Iniative Date Fig. 4. Survival urve for patients with panreati aner. Our results are onitional for iniviuals ying within three years after the iniative event. This means that if a liniian is very sure an iniviual will ie within three years, he or she shoul think of a reommenation for hospie with longer survival for the selete ohorts. We believe that this is a fairly strong statement beause the three-year survival perio we examine is long ompare to the average length of hospie stay (43 ays in our ohorts). Our finings are important in helping to ispel the myth that hospie are hastens a patient s eath. This myth may stem in part from Table 2 Results of Overall Regression an Regression of Hospie Cohort Overall Regression a Regression of Hospie Cohort b Parameters SE P-Value Parameters SE P-Value Interept < < Variables CHF < Breast aner < Colon aner < < Lung aner < < Panreati aner < < Prostate aner Age (years) <60 60e e e þ Female Male White 20 Blak Hispani Asian Other rae Hospie Length of hospie stay < SE ¼ stanar error. a C(p) value of , R-square value of ; all variables are logial (0 or 1). b C(p) value of , R-square value of ; all variables other than length of hospie stay are logial (0 or 1). Eliminate for reunanies of variables. Eliminate to minimize C(p).

8 Vol. 33 No. 3 Marh 2007 Survival of Hospie Patients 245 Table 3 Lengths of Hospie Stay for Cohorts Number of Hospie Patients ¼ Count ALOHS ¼ m Stanar Deviation CHF Breast aner Colon aner Lung aner Panreati aner Prostate aner All above ALOHS ¼ Average length of hospital stay. the fat that hospie professionals not unommonly amit patients who are in very poor shape an near eath. Inee, many patients ontinue to be referre late for hospie or palliative are. The use of opiois an seatives to alleviate symptoms has also ontribute to this pereption, though a growing boy of literature has amasse to ounter this assoiation. 5e9 Clinial observation suggests that numerous fators may ontribute to the inrease longevity we foun in patients eleting to reeive hospie are. First, patients who are alreay in a very weakene onition avoi the risks of overtreatment when they make the eision to enter hospie. This fator may be partiularly relevant to terminally ill onology patients who forego aggressive ure-irete therapies. Intensive meial interventions suh as highose hemotherapy or bone marrow transplantation always arry a signifiant anger of mortality. Seon, entering hospie may improve the monitoring an treatment patients reeive. The Meiare hospie benefit allows patients to reeive meiations that might not be overe in the absene of Part D or other insurane, along with interisiplinary are oorination that rarely ours in the traitional Meiare program. Thir, several stuies have suggeste that psyhosoial supports may ten to prolong life, 11e13 although not all stuies have foun an assoiation. 14,15 Nonetheless, for people who are on the ege of survival, onstant attention to their emotional well-being an physial health may inrease their esire to ontinue living. Stuies of patients with oronary heart isease 16,17 an breast aner 13 have foun that low levels of soial support inrease the risk of morbiity or eath. Without hospie, patients may feel that they are a buren to their family. Although our finings were onsistent aross four of the iagnosis ategories we stuie, it is not lear whether these finings woul be repliate in patients with other isease states. In this stuy we hose very narrowly efine patient ohorts, an further researh shoul be unertaken to etermine whether these finings are appliable to other kins of patients. Not all patients emonstrate inrease survival, an it is probably a subset of patients who may benefit. Future researh in this area will eluiate the appliability of these finings to other patients. The methoology use in this stuy is subjet to limitation in the ability to ontrol for seletion bias. We o not preisely know if some fators relate to the eision to use hospie may be responsible for the results. However, by seleting patients prior to eath with the same linial irumstanes rather than seleting patients who ie an performing a look bak, we believe we have overome seletion bias, at least in part. This stuy provies important information to ispel the myth that hospie hastens eath an suggests that hospie is relate with the longer length of survival by ays or months in ertain terminally ill patients. This extra time might be partiularly important to patients an their families, as it may allow some people to use the en of life as a time of resolution an losure. Aknowlegments The authors gratefully aknowlege the support of the National Hospie an Palliative Care Organization in funing this projet. Referenes 1. Christakis NA, Iwashyna TJ, Zhang JX. Care after the onset of serious illness: a novel laims-base ataset exploiting substantial ross-set linkages to stuy en-of-life are. J Palliat Me 2002;5:515e Christakis NA. Preiting patient survival before an after hospie enrollment. Hosp J 1998;13: 71e Connor S. Hospie: Pratie, pitfalls, an promise. Philaelphia, PA: Taylor an Franis, e119.

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