The meaning of psychomotor symptoms in the treatment of depressive disorders among the elderly. A validation study of the CORE

Depressive disorders are more frequent in the elderly and have a poor prognosis
in terms of chronic or remittent course, co-morbidity with somatic diseases,
functional impairments and cognitive disorders, and increased mortality rates.
Therefore, insight in symptoms and prognosis of depressive disorder in the
elderly is of great importance. Several studies have shown that psychomotor
symptoms have a high discriminating validity and can lead to better classifying
the different subtypes of depression (Sobin and Sackeim, 1997), resulting in a
better choice of therapeutic interventions. A better response to tricyclic
antidepressants (TCA) was shown to be predicted by psychomotor symptoms (Sobin
and Sackeim, 1997). In terms of the predictive value for the treatment with
electro convulsive therapy (ECT) the results were inconclusive. It was shown
that all patients with psychomotor symptoms had a superior response to ECT,
however a distinction between patients with agitation or retardation remained
unclear (Sobin and Sackeim, 1997). Further research is warranted but is
hampered because of the lack of a golden standard to measure psychomotor
symptoms.

Several rating scales for depressive symptoms are available and frequently used
(Montgomery Åsberg Depression Rating Scale (MADRS), Inventory of Depressive
Symptoms (IDS), Geriatric Depression Scale (GDS) etc.). However, none of these
include adequate rating of psychomotor symptoms. Moreover, most rating
instruments are dependent on the subjective opinion of the respondent.
Objective observation of psychomotor symptoms has the advantage that it is
independent of *patient recall* that might be influenced by the depressive mood
(Hickie, Mason en Parker, 1996a).

In 1990 the CORE was developed by Parker and his group (Parker et al., 1990)
and validated in several studies as observational instrument for psychomotor
symptoms in depressive disorders (Parker et al., 1995abc; Parker, 2007). The
CORE has a high inter-rater reliability (0.82-0.87) (Parker, 2007), and was
shown to be of clinical importance in predicting a response on TCA (Schrijvers,
Hulstijn en Sabbe, 2008) and ECT (Hickie, Mason en Parker, 1996a; Hickie et
al., 1996b). Since the initial development by Parker and his group (Parker et
al, 1990), the CORE was translated and validated for other countries (Thuile et
al., 2005), but a Dutch version is lacking.

The aim of this study is to translate the CORE into Dutch and test the
clinimetrical features such as reliability and validity for the Dutch
situation.

Clinical importance:
Once the CORE is validated with this pilot study future research can be planned
and executed with the aim of achieving a better typing of depressive disorders
in the elderly and better insight in the prognostic value of psychomotor
symptoms in depression for medical or ECT treatment. A faster and more
effective treatment of severe depressive disorders is the goal.

Methods:

1. Translating the CORE by back- and forward translating. No patients are
involved at this stage.
2. Data collection:

I. rating instruments
Aside from socio-demographics (age, sex, education, first depressive episode,
number of depressive episodes, duration of index episode, medication (including
dose) somatic history, alcohol and nicotine use) four rating scales will be
drawn: the CORE, MADRS, SRRS (Widlöcher) and IDS. Furthemore, an actimeter will
register movement for 24 hours.
a. The CORE is an 18-item scale based on the observation of psychomotor
symptoms in depressive disorders. In this study five independent psychiatrists
will rate a video tape of an open interview about several subjects, set in a
video-script (see II procedure).
b. MADRS is part of the standard treatment of depressive disorders in the
clinical ward of elderly-psychiatry of Stichting Buitenamstel Geestgronden
(SBG).
c. Salpetriere Retardation Scale (SRRS) (Widlöcher): The Widlöcher is a
subjective (ideational items) as well as an objective (motor and verbal items)
scale to rate motor and mental symptoms in depression. The Widlöcher
Retardation scale is translated and validated in Dutch (Lampe, 2001).
d. The Inventory of Deperssive Symptomatology (IDS) is a self-report
questionnaire on deperssive symptomatology.
e. Actimeter. This is a technique to constantly measure spontaneous motor
activity by a electronic device that looks like a watch and is worn on the
non-dominant hand non-stop for 24 hours. It measures the number of movements
with a acceleration of 0.1 G or more during the day (Dantchev en Widlöcher,
1998). Fluctuations of psychomotor symptoms during the day can be recorded in
an objective way.

II. Procedure
The inclusion of patients is at admission at the ward by the MINI
(Mini-International Neuropsychiatric Interview) and the MMSE (Mini Mental
State Examination). These will be done by the resident in psychiatry or
psychiatrist working in the ward. Normally the MADRS will be done the day after
admission with patients with depressive disorder (common clinical practice).
During the study the MADRS will be done together with the other rating scales
by research students or research assistants (the latter after the students have
finished their internship), hereby limiting the number of times that a scales
is drawn.
After a patient meets the inclusion criteria, he/she will be approached by the
student or research assistant. The goal of the study will be explained, written
information given and the patient will be asked to consent to take part in the
study. If the patient consents an appointment is made to collect the data.
This is according to a set diagram (also see video-script): the patient will be
taken from the ward by the student or assistant to the research examination
room. Coffee/tea will be offered and the goal of the study will be explained
once again.
The DVD recorder will start after patient*s consent. While rating the CORE it
is important that the patient is at ease, therefore the interview will start
with neutral topics such as profession, hobbies, and daily activities. After 10
minutes the interviewer will focus on social demographic data, followed by the
Widlocher and the MADRS. This will take about (around) 30 to 40 minutes. Then
the IDS will be handed to the patient and explained. Finally, the action
measure will be explained and attached to the non-dominant arm with a wrist
band. The interview will be ended by thanking the patient for participating in
the study and by asking if there are any questions or unclarities. An
appointment is made to return the iDS and action measure.
The DVD interview will be shown separately in a different room to 5
psychiatrists working in elderly psychiatry. All 5 psychiatrists will score the
CORE independently.

As the target group consists of clinical patients with a severe depressive
disorder the burden for the participants will be limited as much as possible.
Much of it is already used in the clinical practice (collecting
sociodemographics, MADRS). Exception is the video recording of the interview,
which enables scoring the CORE afterwards, and using the Widlöcher retardation
scale. The additional time investment is estimated to be 1 hour above standard
practice. Thereby the participant will be asked to wear the action meter,
looking like a watch for 24 hours.
None of the intervention is of any risk for the participants.