hospital and community mortality rates among the retarded
TRANSCRIPT
J . ment. Defic. Res. (978), 22, 137 137
HOSPITAL AND COMMUNITY MORTALITYRATES AMONG THE RETARDED*
C. MILLER and R. EYMANSchool of Medicine, University of California at Los Angeles, Mental Retardation and ChildPsychiatry Division, The Neuropsychiatric Institute, Pacific State Hospital Research Group,
Pomona, California, USA
INTRODUCTIONTbe work of McGurley, Mackay and Scally (1972) is one of few studies extant
which contrasts mortality factors between mentally retarded subjects in hospitalsettings with those in, community placements. Mortality studies on institutionalisedpopulations are more extensive. Examples are Tarjan, Eyman and Miller (1969),Foresman and Akesson (1970), and Balakrisbnan and Wolf (1976). The latterreference provides an analysis for an entire country (Canada) and should be especiallyuseful for comparative purposes.
Studies relating to eommunity mortality rates, however, are becoming ofincreasing importance as the trends toward "normalisation" and "de-institutionalisa-tion" accelerate. Periodic investigations are needed properly to evaluate the efTeetof these trends. Comparative mortality is one such measure, as it indicates whetherbasic procedures for maintaining life are adequate (or hopefully, better tban adequate)in the new forms of placement. This paper, therefore, is a replication of certainparts of the McCurley et al. study utilising a different population. Where appropriatetables will be presented wbieb are similar to those found in tbe McCurley et al.study. Tbis study will be divided into tbree parts:
1. A replication of the findings reported by McCurley et al.
2. Discussion of additional factors influencing mortality.
3. A methodological discussion of age at death.
METHOD AND PROCEDUREMeCurley et al. (1972) based their work on a population of retarded individuals
residing in Northern Ireland. The present study sampled mentally retarded receivingservices in tbe southern California area of the United States. There are differencesin terminology and classification between the two countries which require explana-tion. For Northern Ireland, the McCurley et al. study grouped all the communityplacements into one classification; it is not clear whether there is much differentiationof the mentally retarded among placement alternatives. For tbe southern Californiaarea, tbere are four distinct types of community placement whieh tend to seive
*This study was supported in part by National Institute of Child Health and Human Develop-ment Research Grants No. HD-04612 and No. HD-05540 and DHEW/OHD Grant No.54-P-71117/9-02.
Received 1st JVovember, 1977
138 MORTALITY AMONG THE RETARDED
difTerent types of subjects and whieh therefore might be expeeted to illustrate differingpatterns of mortality. They are as follows:
1. Own home placements. The retarded subject is in his own or parentalhome (usually the latter) and uses community services as required. This situation isconsidered ideal in terms of the "normalisation" of the subject.
2. Family care placements. These are homes, run by an unrelated person whoresides in that home, caring for one to five retarded subjects. The residents areusually younger, moderately retarded individuals. In-house intensive medical careis not available.
3. Board and care homes. These facilities, also known as Group Homes, aredesigned for older persons who do not require intensive medical care. They con-stitute larger facilities, containing up to fifty or more mentally retarded persons in asingle residence. Most of them are characterised by moderate levels of retardation.
4. Gonvalescent hospitals. These facilities are designed specifically as alterna-tives to institutional placement for severely and profoundly retarded persons, most ofwhom require intensive twenty-four-hour care. They usually care for fifty to morethan a hundred clients which endows them with some of the characteristics of smallinstitutions. This type of facility is very common in Galifornia. Their presence inCalifornia provides an opportunity to characterise mortality in a community settingdesigned expressly for the care of the more severely retarded.
To facilitate comparison between the McCurley et al. study and this investigation,similar categories of mental retardation will be utilised. Gelof (1963) providestables comparing various classification schemes for the retarded. Using Gelof'sfindings, British and American levels of retardation are equated as follows:
British Term American Equivalent
Feeble-minded Borderline and mild retardationImbecile Moderate and Severe retardationIdiot Profound retardation.
The correspondence between these levels of retardation is based on measuredintelligence and is close except that the Idiot category is characterised as those withan I Q of 0-25, whereas the Profound category is characterised by an I Q of 0-19.It is felt that this difference is not of any noteworthy significance.
The sample studied consisted of the case load of one institution in southernCalifornia and two community areas surrounding that institution for the time period1972-1975. The community agencies serving the retarded are administrativelyindependent of the institution, and are of three different types. The first is knownas a Continuing Care Service Section (CCSS), administered by the State of Cali-fornia. As the name implies, this agency serves many subjects who at one time \vereinstitutionalised. Recently, however, an increasing number of the mentally retardedin the area are served directly by the agency without previous insdtutionalisation.
The second type of community agency is known as a Regional Centre. Aregional centre contracts with the State of California for the care of the mentallyretarded, and is responsible for the type of placement that will be made. Placementsmay include insdtutionalisation. The majority of the regional centre's cases are own
C. MILLER and R. EYMAN 139
home placements, and relatively few placements are made in convalescent hospitals.The CCSS, on the other hand, makes extensive use of convalescent hospitals.
A third type of community placement concerns those who have previouslybeen institutionalised but more recently have been transferred to a communityfacility. The institution retains administrative control over the placement. It wasconsidered of interest to compare the mortality of these individuals with thoseresidents still in an institution and those who were never institutionalised.
The data for this study was collected as a part of a longitudinal investigationconcerned with the long-term developmental effects of differing placements andenvironments in a sample of care systems in the United States. Mortality is considereda crude measurement of health care. The total geographical area served has apopulation of approximately seven million people.
The McCurley et al. study endeavoured to separate the study population intocommunity cases vs. institution cases on the basis of the length of time spent in thetwo settings. The reason for this procedure was to allocate deaths correctly andespecially to avoid miscounting cases who were returned to an institution in a seriouscondition and subsequently died there.
Using case matching procedures, individuals were allocated to one placement.Readmissions to the institution were deleted and the subject was treated as aninstitutional resident throughout the period of study. As previously stated, communitycases who had been institutionalised were classified separately. Three groups aretherefore identified: (1) Institution residents, (2) Community placed cases, and (3)Cases previously institutionalised who resided in the community during the periodof study.
It should be noted that it is not current practice in southern California toreturn seriously ill cases to an institution when they have been living elsewhere;therefore virtually all deaths occur in the placement where the subject was residing.If death occurred in a community general hospital, the death was allocated to thesubject's last placement.
FINDINGSTable 1 presents the crude death rates, by sex and type of placement for the
years 1973 to 1975. The results are not appreciably different from the rates reportedby McCurley et al. (1972, p. 59) for either the institution or community settings.However, it is noteworthy that the death rates for the convalescent hospitals weredefinitely higher than for the institution, which in turn had higher rates than the"other" community facilities. It is also likely that some of these differences canbe accounted for by the type of individual who resides in each placement category.
Table 2 provides mortality rates by age and level of retardation. Table 2 issimilar in construction to the McCurley et al. Table 2, page 61, except that (a) theperiod covered is less, and (b) the data is presented in terms of a follow-up of thoseresiding in the indicated placement on the first day of 1973. It is clear that some ofthe numbers involved are small for meaningful conclusions, but the results arepresented for completeness. The death rates were computed on the basis of deaths
140 MORTALITY AMONG THE RETARDED
Table 1Annual death rates per 1,000 at risk, selected Southern California placements, 1973-1975,
by sex
A. INSTITUTION
January 1stPopulationReleasesDeaths
Death rate/1,000
Male
10735119
18
I7JEemale
7192415
21
1974Male
12404622
18
Female
8261620
24
Male
12244625
21
1975Female
83722
9
11
B. CONVALESCENT HOSPITALS
January 1stPopulationReleasesDeaths
Death rate/1,000
Male
2121613
64
Female
2372114
57
1974Male
23904
17
Female
26958
30
Male
2882010
36
1975Female
2911210
35
C. OTHER PLACEMENTS
January 1stPopulationReleasesDeaths
Death rate/1,000
IbMale
1083258
13
14
Female
796217
6
9
Male
1419504
3
>74Female
1095434
4
Male
139854
3
2
1975Female
105944
2
3
over the entire three-year period, and are presented as average single-year mortalityrates. The rates are adjusted for releases from the initial (1973) status by countingsuch cases as being in the population for one-half the follow-up period (1.5 years).In addition, some cases had to be excluded because of unknown levels of retardation.Level of retardation was available for 97 per cent of the total sample.
I t may be observed in Table 2 that both the convalescent hospitals and theinstitution provided care for the more severely retarded subjects. However, those inconvalescent hospitals were generally older. All ages were represented in other typesof placements. There were some important differences in mortality rates among thesettings when sub-divided by level of retardation. Table 2 indicates that the mortalityrate for the profoundly retarded was higher in community settings than in theinstitution. Still, for other levels of retardation, community rates were generallylower than the institutional rate with the exception of the convalescent hospitals.Rates for previously institutionalised cases were higher than for those never insti-tutionalised. The institution death rates are very similar to those presented by
C. M : I L L E R and R. EYMAN 141
Balakrishnan and Wolf (1976, p. 353) for Canada. Convalescent hospitals had highermortality for all levels of retardation. The mortality rates for "other placements"were lower, consonant with results of the McCurley et al. study.
Additional Mortality FactorsThere is considerable evidence (Edgerton, Eyman and Silverstein, 1975) that
ambulatory ability is highly related to mortality, especially if contrasting those totallyunable to walk with those who have at least some ability to do so. Total inability towalk is most common among the profoundly retarded and less so as the level ofretardation approaches the normal range (Tarjan, Dingman and Miller, 1960;
Table 2Mortality rates by type of placement, age and level of retardation-
1973-1976
Level
Age
0-45-9
10-1415-1920-2930-3940-4950-5960-6970-t-
Total
Borderline-mild
06
102317115
1152
90
died
0121000000
4
DRjlOOO
0677819000000
17
A. Institution
Moderate-severe
N
874
119161170626118135
691
died
2246433301
28
DRU
1111012148
1718670
83
14
-Three-year follow-up,
Profound
N1055
15021521767401730
died
28
10211833000
DR/1000
78542435301626
000
774 65 28
Total
B. Convalescent hospitals, never institutionalised
Level
Age
0-45-9
10-1415-1920-2930-3940-4950-5960-6910 +
Borderline-mild
N Died DR/1000
(insufficient cases)
Moderate-severe
N
312113
1472310
Died
2010100200
DR/1000
3330
440
3300
33300
513101048187430
Profound
Died .
0103461000
DR/h
0280
12533
13851000
56 42 118 15 46
142 MORTALITY AMONG THE RETARDED
Level
Age
0-45-9
10-1415-1920-2930-3940-4950-5960-6970-f
Table 2-—cont.
C. Other placements, never institutionalised
Borderline—mild
N
1284755
12241281652
Died
0000200000
DR/IOOO
0000700000
Moderate—severe
^ •
19487272
15858292151
Died DR/IOOO
0000110000
0000270000
JV
1317
1321
46500
Profound
Died DR/IOOO
0002000000
000
63000000
Total 351 483 70 11
Total
D. Convalescent hospitals previously institutionalised
Level
Age
0-45-9
10-1415-1920-2930-3940-4950-5960-6970-J-
Borderline—mild
7V Died DR/IOOO
(insufficient cases)
Moderate-severe
JV
0016
322014820
Died
0000212110
DR/IOOO
0000
27206151
2220
0119
893317740
Profound
Died
0003
1143210
DR/IOOO
100
167494469
12195
0
83 34 161 24 54
E. Other placements, previously institutionalised
Level
Age
0-45-9
10-1415-1920-2930-3940-4950-5960-6970-1-
N
04
198
56472628166
Borderline—mild
Died
0000000010
DR/IOOO
00000000
350
N1
2788
119173784328
73
Modera te—severe
Died
1233411000
DR/IOOO
667331613126
13000
N
526444920
85600
Profound
Died
1363100000
DR/IOOO
955977362700000
Total 210 567 15 13 163 14 44
C. MILLER and R. EYMAN
Table 3Three-year survival by placement, level of retardation, and ambulation
143
Group
No.
1.2.3.4.
5.6.7.8.
9.10.11.12.
Placement
InstitutionInstitutionInstitutionInstitution
Conv. hosp.Conv. hosp.Conv. hosp.Conv. hosp.
Other placementsOther placementsOther placementsOther placements
Retardationlevel
ProfoundProfound
Severe-moderateSevere-moderate
ProfoundProfound
Severe—moderateSevere-moderate
ProfoundProfound
Severe—moderateSevere-moderate
Ambulatory
NoYesNoYes
NoYesNoYes
NoYesNoYes
Died
44211018
14241
1101
Survived
194508
76580
90193332
194618
423
PP.dyi
0.1850.0400.1160.030
0.1350.0950.1080.030
0.0500.0210.0000.002
The following comparisons, using the Fisher exact statistics, are significantly different (<0.01):1 vs. 2, 3 vs. 4, 1 vs. 10, 2 vs. 5, 4 vs. 12, 7 vs. 12.
O'Connor, Justice and Payne, 1970). Tbe extent of ambulation, however, has notbeen included routinely in studies of mortality among the retarded.
Information on walking ability during the study period was available on anannual basis for the majority of those placed in the institution (99.6 per cent), con-valescent hospitals (96.5 per cent) and community settings (92.3 per cent). However,for those individuals previously institutionalised but later placed in the community,this data was not obtainable for most subjects. Hence, this group was not included inthe analysis of walking ability.
As a result of missing information and the further fractionation of the sampleinto two subgroups of walking ability within placement type and level of retardationgroupings, mortality rates become too unstable to draw ready conclusions from simplestatements of the rates themselves. Nevertheless, it did seem appropriate to use smallsample statistics and utilise the proportion dying within the follow-up period 1973-1976(crude mortality rate) as the basis of measurement, and present the results in termsof significance tests.
Table 3 suggests several conclusions based upon this type of analysis:(a) A mortality differential by degree of ambulation was clearly present in the
institution; nonambulatory residents had a definitely higher crude mortality rate.(b) For convalescent hospitals and other community settings, tbis differential
was not significant.(c) Apparent differences in the crude mortality rates for the profoundly retarded
between convalescent hospitals and the institution without consideration of ambula-tion were considerably reduced when ambulation was introduced, reflecting alarger proportion of nonambulatory individuals in the convalescent hospitals. For
144 MORTALITY AMONG THE RETARDED
example, there were no significant differences between the crude mortality rates forconvalescent hospitals and the institution when ambulatory status was considered.
(d) The small number of cases in most categories and the very small number ofdeaths in all categories does not premit any definite statements about other com-munity placements except the crude mortality rates were very low.
Age at Death
An opportunity was available through this data to make some comparisonson the median age at death of the mentally retarded. Generally, the results of differentstudies are not directly comparable to one anotber. For example, the median age atdeath can be estimated by ascertaining the median point of the age at death distribu-tion, but the number of deaths are related to the age distribution of the populationat risk and the age-specific death rates. For comparability among studies, the popula-tion should be standardised in some manner (Shryock and Siegel, 1973).
A convenient standard population for the institutionalised retarded is availablefrom Balakrishnan and Wolf (1976, p. 643). Age, level of retardation, and sexspecific population distributions were obtained from that source. Using the Canadianpopulation as a standard, death rates observed for the institution in this study andthe McCurley et al. study were recalculated as if their retarded residents bad tbesame characteristics as the Canadian residents. Standardised estimates of median ageat death were then computed.
Median age at death was preferred because of skewness evident in tbe distribu-tion of age at death for the severely and profoundly retarded (McCurley et al., 1972).Although Balakrishnan and Wolf (1976) did not present median ages at death bylevel of retardation, they did provide tbe data for estimates of them from their tables1, 8, and 9.
The estimates resulting from the above procedure can only be used to compareinstitutions. Admissions to institutions by age are not proportional to the age distribu-tion of the retarded in the general population. In particular, there is a substantialunder-representation of admission under four years of age to institutions.
Table 4 provides standardised estimates of median age at death for institutional
Table 4Estimates of median age at death, institutional populations
Profound Severe-moderateSource Reported Standardised Reported Standardised
Balakrishnan and Wolf 24. U 24. U 38.4^ 38.4'McCurley e< a/. 9.0» 14.5 39.5' 40.6California Institution 18.0= 16.5 20.0^ 38.5
'Using Balakrishnan and Wolf (1976) estimated using Tables 1, 8 and 9.^Interpolation of death distribution of Table 2.^Assuming a 60-40 sex ratio.
C. MILLER and R. EYMAN 145
populations from three different studies.* Although these estimates should be inter-preted with caution, they do provide relatively consistent statistics on average age atdeath for these retarded groups. In other words, the average age at death appearsremarkably stable across studies, if sex, age, and level of retardation are equated.Since the Balakrishnan and Wolf study had access to the largest population ofinstitutionalised retarded individuals, the characteristics of their subjects seemed thebest source for standardisation. Given that the residents in Canadian institutionsare indeed representative of other institutions, the averages of age at death reportedin Table 4 could be generalised to other settings.
SUMMARYThe findings of McCurley et al. are generally replicated by this study. Com-
munity rates are usually lower than those of comparable institutional residents,except for convalescent hospitals used for the care of the profoundly retarded in theUnited States.
Attention is drawn to the sharp mortality difference between ambulatory andnon-ambulatory retarded individuals and the affect of the ability to walk can haveon the estimation of mortality rates. The ambulation factor should be consideredmore routinely in future studies.
Finally, a revision of the usual method of estimation of age at death wasattempted. The utility of the method, similar to standardisation procedures widelyused in demography, provides estimates which are more directly comparablebetween studies.
REFERENCESBALAKRISHNAN, T . R. and WOLF, L. C. (1976) Life expectancy of mentally retarded persons
in Canadian, institutions. Amer. J. ment. Defic. 80, 650.EDGERTON, R. B., EYMAN, R. K. and SILVERSTEIN, A. B. (1975) Mental retardation system.
In: N. HoBBS (ed.) Issues in the Classification of Children Vol. II. San Francisco: Jossey-Bass.Chpt. II .
FoRESSMAN, H. and AKESSON, H . O . (1970) Mortality of the mentaly deficient: A study of12,903 institutionalised subjects. J. ment. Defic. Res. 13, 276.
GELOF, M . (1953) Comparisons of systems of classification, relating degree of retardation tomeasured intelligence. Amer. J. ment. Defic. 68, 297.
MCCURLEY, R . , MACKAY, D . N . and SCALLY, B . G . (1972) The life expectation of the mentallysubnormal under community and hospital care. J. ment. Defic. Res. 16, 57.
O'CONNOR, G. , JUSTICE, R . S. and PAYNE, D . (1970) Statistical expectations of physicalhandicaps of institutionalized retardates. Amer. J. ment. Defic. 74, 541.
SHYROCK, H . S., SIEGEL, J . S. and Assoc. (1973) The methods and materials of demography. Vol. 1.U.S. Department of Commerce, Bureau of Census, Washington, D.C.
TARJAN, G. , DINGMAN, H . F . and MILLER, C . R . (1960) Statistical expectations of selectedhandicaps in the mentally retarded. Amer. J. ment. Defic. 65, 335.
TARJAN, G. , EYMAN, R . K . and MILLER, C . R . (1969) Natural history of mental retardationin a state hospital revisited. Amer. J. Dist. Child. 117, 609.
TARJAN, G. , MILLER, C . R . and EYMAN, R . K . Life tables for the institutionalized retarded.(Research in progress.)
•Median age at death was not estimated for the borderline-mild retarded because therewere too few cases for meaningful computation.