Background and aims
Orexins/hypocretins are orexigenic peptides implicated in the regulation of feeding behavior and the sleep/wake cycle. Little is known about the functioning of these peptides in anorexia nervosa (AN). The aims of the current study were to evaluate the extent to which orexin-A might be linked to sleep and treatment outcome in AN.
Method
Fasting plasma orexin-A concentrations were measured in 48 females with AN at the start of a day hospital treatment and in 98 normal-eater/healthy-weight controls. The Pittsburgh Sleep Quality Index was administered at the beginning of the treatment as a measure of sleep quality. Other psychopathological variables were evaluated with the Symptom Checklist-Revised (SCL90R) and the Eating Disorder Inventory-2 (EDI). Patients were assessed at the start and end of treatment by means of commonly used diagnostic criteria and clinical questionnaires.
Results
The AN patients presented more sleep disturbances and poorer overall sleep quality than did the healthy controls (p = .026) but there were no global differences between groups in plasma orexin-A concentrations (p = .071). In the AN sample, orexin-A concentrations were associated with greater sleep disturbances (|r| = .30), sleep inefficiency (|r| = .22) and poorer overall sleep (|r| = .22). Structural Equation Modeling (SEM) showed that both elevated orexin-A concentrations and inadequate sleep predicted poorer treatment outcome.
Conclusion
Plasma orexin-A concentrations contribute to poor sleep quality in AN, and both of these variables are associated with therapy response.This
manuscript
was
partially
supported
by
grants
from
Insti-
tuto
Salud
Carlos
III
(FIS
PI14/290
and
CIBERobn)
and
Fondo
Europeo
de
Desarrollo
Regional
(FEDER)
a
way
to
build
Europe,
but
also
AGAUR
de
la
Generalitat
de
Catalunya
(2014SGR1672)
and
PROMOSAM
(PSI2014-56303-REDT),
Spain.
CIBEROBN,
CIBERSMA
and
CIBERESP
are
all
initiatives
of
ISCIII.
Sarah
Sauchelli
is
recipient
of
a
pre-doctoral
Grant
(2013–17)
by
IDIBELL.
José
C.
Fernández-
García
is
recipient
of
a
research
contract
from
Servicio
Andaluz
de
Salud
(SAS)
(B-0033-2014).
The
funders
had
no
role
in
the
study
design,
data
collection
and
analysis,
decision
to
publish,
or
prepa-
ration
of
the
manuscript