Life Events, Mental Health and Learning Disability

ORIGINAL ARTICLE
Mental Health in Adults With Mild and Moderate Intellectual
Disabilities
The Role of Recent Life Events and Traumatic Experiences Across the Life Span
Almudena Martorell, MA,*† Elias Tsakanikos, PhD,‡ Amada Pereda, PhD,† Pedro Gutie´rrez-Recacha, PhD,†
Nick Bouras, MD,‡ and Jose´ Luis Ayuso-Mateos, MD*
events. Life events such as bereavement, loss of a job, or serious
Abstract: The aim of the present study is to investigate the association
financial problems are stressful experiences that require substantial
between recent life events and traumatic experiences across the life span and
adjustment efforts, and can trigger psychopathological manifesta-
psychiatric disorders in people with ID.
tions in vulnerable individuals (Brown and Harris, 1989; Paykel,
One hundred seventy-seven individuals with mild and moderate intellectual
2001; Tiet et al., 2001a; Goodyer, 1993). It is, therefore, not
disability and their principal carers were assessed. Psychiatric disorders were
surprising that the impact of recent life events has been relatively
evaluated with a semistructured psychiatric interview, the Psychiatric Assess-
studied in people with ID (Coe et al., 1999; Dekker and Koot, 2003;
ment for Adults with Developmental Disabilities. This interview also includes a
Hastings et al., 2004; Hatton and Emerson, 2004; Owen et al., 2004;
checklist of life events experienced over the previous 12 months, which was
Hamilton et al., 2005; Esbensen and Benson, 2006; Tsakanikos et
assessed through key informants. Presence of traumas was assessed through
Allen’s trauma history screen, also administered to key informants. After a
al., 2007). However, very little research has been conducted on
descriptive analysis, binary logistic regression was used to see whether traumatic
traumatic experiences across the life span, except for isolated expe-
events and life events predicted the presence of ICD-10 disorders.
riences, such as sexual abuse (Turk and Brown, 1993; Westcott and
A 75% of the participants had experienced at least 1 traumatic event
Jones, 1999; Firth et al., 2001; Sequeira and Hollins, 2003).
during their life span, and 50% of the participants had experienced at least 1
It has often been claimed that the presence of ID increases the
life event in the 12 months previous to the study. Binary logistic regression
number, severity, and impact of a wide range of recent life events
showed that exposure to 1 or more traumatic experiences significantly
(Bramston et al., 1999; Tiet et al., 2001b; Hatton and Emerson, 2004).
increased the odds of a mental disorder (OR
1.8), as did exposure to life
Although the impact of a wider range of traumatic experiences has been
events (OR
1.4). However, when both life events and traumatic experi-
overlooked, probably because of some overlap between the 2 classes of
ences were entered together in the model, calculation of odds ratios revealed
events (given in Ben-Ezra and Aluf, 2006), it is conceivable that the
that traumatic experiences significantly increased the odds of ICD-10 disor-
presence of ID may also increase the number, severity, and impact of
ders (OR
1.7) although life events were no longer significant.
traumatic experiences across life span.
Though they have been less studied by the literature regarding predictors
Consequently, the purposes of the present study were to: (a)
of mental illness in people with intellectual disability, traumatic experiences
re-examine the documented relationship between recent life events
seem to play a more important role in psychopathology than life events.
and ICD-10 disorders; (b) examine the relationship between ICD-10
disorders and traumatic experiences across the life span; (c) look
Key Words: Life events, trauma, intellectual disability, psychiatric disorders.
into the outcomes of a model where both traumatic and life events
(J Nerv Ment Dis 2009;197: 182–186)
were introduced together, to throw some light on the impact of these
negative experiences.
A number of studies have shown higher rates of mental health
disorders in people with intellectual disability (ID), compared
METHOD
with those without ID (Campbell and Malone, 1991; Menolascino
Participants
and Fleisher, 1991; Borthwick-Duffy, 1994; Cooper et al., 2007; but
also see Whitaker and Read, 2006), suggesting an increased biopsy-
All clients, and their key informants, of the Carmen Pardo-
chosocial vulnerability (ICF, WHO, 2001; Matson and Sevin, 1994).
Valcarce Foundation’s sheltered workshops in Madrid were inter-
Greater vulnerability in people with ID is probably the result of both
viewed for the present study. These sheltered workshops belong to
external and internal factors including increased dependency on
the ID network of the Madrid Regional Administration’s Depart-
others and reduced cognitive mechanisms to cope with stressful
ment of Social Services, which is the main network for people with
ID in this city. During the time of the study, 180 adults with
intellectual disabilities were working at the Foundation’s sheltered
*Department of Psychiatry, Hospital Universitario de la Princesa, Universidad
workshops, all of whom were asked to participate, along with their
Auto´noma de Madrid, CIBER-SAM, Madrid, Spain; †Fundacio´n Carmen
main carers. Only 1 client and 2 key informants did not give their
Pardo-Valcarce, Madrid, Spain; and ‡Estia Centre, Institute of Psychiatry,
consent for the interview, resulting in a final sample of 177. Regarding
King’s College London, London, United Kingdom.
Supported by the Spanish Ministry of Health, Carlos III Health Institute, Spanish
clients, participants were 62 women (35%) and 115 men (65%), with
National Health Research Fund (Fondo de Investigacio´n Sanitaria, FIS,
a mean age at the time of the study of 29.6 years (SD
6.6). Degree
PI061843), and by the CIBER SAM also funded by the Spanish Ministry of
of disability based on ICD-10 criteria (WHO, 1994) was obtained
Health.
Send reprint requests to Almudena Martorell, MA, Fundacio´n Carmen Pardo-
through the Foundations’ initial assessments including Wechsler
Valcarce, Monasterio de las Huelgas, 15, 28049 Madrid, Spain. E-mail:
Adult Intelligence Scale-III (WAIS-III) (Weschler, 2001). There
almudena.martorell@uam.es.
were 127 clients with mild ID (72%) and 50 with moderate ID
Copyright © 2009 by Lippincott Williams & Wilkins
(28%). Regarding key informants, there were 159 (95%) parents (139
ISSN: 0022-3018/09/19703-0182
DOI: 10.1097/NMD.0b013e3181923c8c
or 83% mothers; 20 or 12% fathers), and 10 first-degree relatives.
182
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The Journal of Nervous and Mental Disease • Volume 197, Number 3, March 2009
Life Events in ID
Assessments
TABLE 2.
Proportion of Sample Exposed to Each Traumatic
Data on psychiatric symptoms and recent life events were
Experience During Life Span
gathered using the Psychiatric Assessment for Adults with Devel-
opmental Disabilities (PAS-ADD) (Moss et al., 1993; 1997). The
Traumatic Experience
% of Sample
PAS-ADD is a semi-structured interview for use with respondents
Learning of the sudden death or serious injury of a
51%
who have ID and for key informants. PAS-ADD is based on items
spouse, child, parent, close relative, or friend
drawn from the Schedules for Clinical Assessment in Neuropsychi-
Being physically threatened, assaulted, or attacked
17.9%
atry (WHO, 1994b; Va´zquez-Barquero, 1994), and it includes such
Being in an accident that was life-threatening or
14.1%
features as: parallel interviewing of patient and informant; a 3-tier
resulted in serious injury
structure to provide a flexible interview appropriate to the patient’s
Being tormented, terrified, stalked, or humiliated by
10.3%
intellectual level; use of a memorable “anchor event” in the patient’s
someone repeatedly and Intentionally
life to improve time focus; and simplified wording, improved orga-
Having a life-threatening illness
8.3%
nization and layout. The overall interview is completed in approx-
Witnessing someone being killed, maimed, or
6.4%
imately 1 hour. After the interview, ICD-10 (WHO, 1994a) diag-
seriously injured
noses were made by an expert group designated for the study (1
Being sexually molested (someone touched or felt
4.5%
specialist psychiatrist and 2 specialist psychologists). Posttraumatic
your genitals when you did not want them to)
stress syndrome and obsessive-compulsive disorder are not explored
Being imprisoned or held captive
4.5%
in the PAS-ADD interview, so a separate short interview elaborated
Being in a natural disaster (fire, flood, earthquake,
3.8%
for the study, also based on the Schedules for Clinical Assessment
tornado) that was life-threatening or resulted in
in Neuropsychiatry, was employed. It must also be noted that though
serious injury
problem behaviors are also categorized in the ICD-10, the PAS-
Accidentally causing serious injury or death to another
3.2%
ADD does not analyze them and were therefore not included in the
person
present study. The same must be said about personality disorders.
Surviving an attempted rape (someone tried to have
1.9%
The PAS-ADD interview also includes a checklist of life events
sexual intercourse with you when you did not
experienced over the previous 12 months (as given in Table 1), which
want to by threatening you or using force)
was assessed through key informants. The sum of all the life events
Surviving a completed rape (someone had sexual
1.3%
experienced over the previous 12 months was the variable used.
intercourse with you when you did not want to
Finally, Allen’s trauma history screen (Allen et al., 1999) was
by threatening you or using force)
also administered to key informants. The Trauma History Screen
Being physically tortured by someone
0.8%
was initially developed to screen for potentially traumatic events in
Being in military combat or a war zone
0%
women admitted for specialized treatment of trauma-related disor-
No. traumatic experiences
ders, though has been used in multiple settings (Gibbs and Rude,
None
25%
2004) and has been translated into Spanish with acceptable data
1
31%
2
22%
2
11%
TABLE 1.
Proportion of Sample Exposed to Life Events
During the Last 12 Months
Life Events
% of Sample
regarding reliability and validity (Landeta and Calvete, 2002). The
Death of first-degree relative
19%
questionnaire contains 14 items (Table 2), assessing possible trau-
mas, and respondents indicate the frequency with which they have
Death of close family friend or relative
17%
experienced these traumas, as well as the age at which the trauma
Moving house or residence
8.4%
occurred. In the present study, the sum of the traumatic events was
Serious illness or injury
6.7%
employed as an independent measure.
Something valuable lost or stolen
5.6%
Serious illness of close relative
5%
Data Analysis
Break-up of steady relationship
3.9%
Firstly, a descriptive analysis of frequency and type of trau-
Serious problem with close friend, neighbour, or relative
3.4%
matic and life events was carried out. Comparative and correlational
(when appropriate) analyses were then undertaken to assess possible
Unemployed or seeking job
2.8%
associations between key demographic variables (gender, age, and
Sexual problems
1.7%
level of ID) and our main study variables (ICD-10 disorders,
Problems with police or other authority
1.7%
traumatic experiences, and recent life events). Binary logistic re-
Alcohol problems
1.1%
gression was then used to see whether traumatic events and life
Problems with illegal drugs
1.1%
events separately predicted the presence of ICD-10 disorders while
Laid off/sacked from work
1.1%
controlling for possible confounding effects from other variables.
Major financial crisis
1.1%
Finally, binary logistic regression analyses were again performed,
Separation or divorce
0.6%
this time introducing both life events and traumatic experiences as
Retirement from work
0.6%
predictors of ICD-10 disorders. The Statistical Package for Social
No. life events
Sciences (SPSS version 13.0) was employed for all the analyses.
None
49.8%
1
29.7%
RESULTS
As can be seen in Table 1, 75% of the participants had
2
12.8%
experienced at least 1 traumatic event during their life span, and
2
6.7%
50% of the participants had experienced atleast 1 life event in the 12
© 2009 Lippincott Williams & Wilkins
183

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Martorell et al.
The Journal of Nervous and Mental Disease • Volume 197, Number 3, March 2009
months previous to the study (Table 2). Moreover, 38% of our
significantly more prevalent (p
0.5) among our male participants.
participants presented ICD-10 disorders. Typology of these disor-
No other significant differences were found. The number of trau-
ders is described in Table 3.
matic experiences and life events did not correlate significantly, nor
Table 4 presents the comparative analysis between our out-
present significant differences compared with any of the key demo-
come variable (ICD-10 disorder) and key demographic variables
graphic variables (p
0.5).
(gender, age, and IQ scores). As can be seen, ICD-10 disorders were
Pearson correlation between traumatic experiences and life
events was 0. 28 (p
0.01), suggesting that there was a substantial
amount of unshared variance between the 2 measures (92.2%).
Binary logistic regression results are presented in Table 5.
TABLE 3.
Typology of ICD-10 Diagnosis
Calculation of odds ratios (OR) showed that exposure to one or more
Diagnosis
n
%
traumatic experiences significantly increased the odds of a mental
No ICD-10 disorders
110
62%
disorder (OR
1.8; 95% CI
1.2–2.5), as did exposure to life
events (OR
1.4; 95% CI
1.1–2.0). In both cases, gender was
ICD–10 disorders
67
38%
introduced into the model to control for the differences in ICD-10
F20–F29
Schizophrenia, schizotypal, and delusional
16
24%
disorders between female and male participants (as shown in the
disorders
bivariate analysis).
F30–F39
Mood affective disorders
21
31%
Finally, when both life events and traumatic experiences were
F40–F48
Neurotic, stress-related, and somatoform
21
31%
entered together in the model, calculation of odds ratios revealed
disordersa
that traumatic experiences significantly increased the odds of
F50–F59
Behavioral syndromes associated with
4
6%
ICD-10 disorders (OR
1.7; 95% CI
1.2–2.4) although life
physiological disturbances and physical
events were no longer significant (Table 6).
factors
F84
Pervasive developmental disorders
5
8%
aSimple phobias were excluded due to their non-clinical relevance.
DISCUSSION
Though life events have been taken into account in the
literature of ID, traumatic experiences have been largely ignored.
TABLE 4.
Comparative Analysis Between Key
The present data suggest that both life events and traumatic expe-
Demographical Variables and Outcome Variables
riences were related to ICD-10 disorders in adults with ID. Never-
theless, when introduced together in a regression model, life events
Presence of
No Detected
no longer seemed significant. This latter result indicates that trau-
ICD-10 Disorder ICD-10 Disorder
Statistical
matic experiences may be more important predictors of psychopa-
N
61 (34%)
N
116 (66%)
Significance
thology than life events.
Age
Our analysis also suggests that about one-third (34%) of our
Mean (SD)
29.4 (5.7)
29.8 (7.1)
t
0.35;
participants had an ICD-10 disorder. Epidemiological studies under-
df
175 NS
taken in Spain with analogous populations have shown similar rates
Gender
of ICD-10 disorders (Salvador-Carulla et al., 2000). Considering the
Male n (%)
51 (43.6%)
66 (56.4%)
limitations often present when assessing rates of psychopathology in
Female n (%)
16 (26.8%)
44 (73.2%)
2
5.15; df
1*
people with ID (Smiley, 2005), the present prevalence rates do not
IQ
vary much from other point prevalence studies (Whitaker and Read,
2006). The same is true for the percentages of life events, where
Mean (SD)
63.5 (12.2)
61.5 (10.3)
t
1.17;
df
121,3; NS
even the order in types of life events largely coincides with previous
studies (Hastings et al., 2004). Nevertheless, regarding traumatic
NS indicates not significant.
experiences across life span, absence of previous studies prevent us
*p
0.5.
from making similar comparisons.
TABLE 5.
Odds Ratios of Predictor Variables: Agreement Percentages
Estimated %
ICD-10 Disorder
Variables
OR (95% CI)
Observed %
No ICD-10
Yes ICD-10
Correct %
Traumatic experiences
1.8 (1.2–2.5)*
Gender
2.17 (1.1–1.5)**
No ICD-10
87
21
80.9
Yes ICD-10
39
30
43.5
Global %
66.0
Nagelkerke R2
0.27
Life events
1.4 (1.1–2.0)**
Gender
2.3 (1.2–4.6)**
No ICD-10
103
8
92.8
Yes ICD-10
54
12
18.2
Global %
65.0
Nagelkerke R2
0.07
NS indicates not significant to the model.
*p
0.01; **p
0.5.
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The Journal of Nervous and Mental Disease • Volume 197, Number 3, March 2009
Life Events in ID
TABLE 6.
Odds Ratios of Both Predictor Variables: Agreement Percentages
Estimated %
ICD-10 Disorder
Variables
OR (95% CI)
Observed %
No ICD-10
Yes ICD-10
Correct %
Traumatic experiences
1.7 (1.2–2.4)*
Life events
1.2 (0.8–1.7) NS
No ICD-10
89
17
83.0
Gender
2.2 (1.1–4.6)**
Yes ICD-10
43
28
39.3
Nagelkerke R2
0.13
Global %
65.8
NS indicates not significant to the model.
*p
0.01; **p
0.5.
Among our participants, 75% had experienced at least 1
interventions. In a diathesis model, traumatic experiences across life
traumatic life event during their life span. It should be also noted that
span would count as predisposing factors, whereas life events would
51% of the traumatic experiences were related to the “learning of the
be precipitating ones. This is particularly important, as it is generally
sudden death or serious injury of a spouse, child, parent, close
accepted that prevention should take place when predisposing fac-
relative, or friend.” Interestingly, age did not correlate significantly
tors are present, not just in the presence of precipitating ones.
with the number of traumatic events. As traumatic experiences were
assessed for the whole life span, it would have been expected that
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