The Epidemiology of Depressive Symptoms and Poor Sleep: Findings
from the English Longitudinal Study of Ageing (ELSA)
Published online: 4 December 2017
Purpose The reasons for the comorbidity between depressed mood and poor sleep are not well understood.
Method Participants were 5172 adults aged 50 years and older from the English Longitudinal Study of Ageing. Sleep was
measured via self-report and depressive symptoms using the Centre for Epidemiological Studies Depression scale.
Results Greater depressive symptoms and sleep complaints were associated with female sex, non-cohabitation, relative
poverty, smoking, infrequent physical activity, infrequent alcohol consumption, higher body mass index (BMI), diagnosis
of hypertension, coronary heart disease, diabetes/high blood glucose, pulmonary disease, arthritis, and higher levels of
fibrinogen and C-reactive protein (all p < 0.05). At a 4-year follow-up, depressive symptoms and sleep complaints were
both predicted by baseline depressive symptoms and sleep complaints, relative poverty, smoking, physical inactivity, BMI,
and arthritis (all p <0.05).
Conclusion Depressive symptoms and sleep complaints share a range of correlates cross-sectionally and prospectively.
These findings highlight the common comorbidity between depressive symptoms and sleep complaints underscoring the
need for further research to understand their combined detrimental effect on long-term health and wellbeing.
Keywords Depressive symptoms
Depression is now one of the leading causes of global disease
burden  and subclinical levels of depression in community-
dwelling adults are known to be highly prevalent in England .
Elevated depressive symptoms have been associated with an
array of poor physical health outcomes, including increased risk
of diabetes  and coronary heart disease . Late-life depres-
sion has been associated with dementia  and there is some
evidence for an association with cancer , though this literature
is mixed . Understanding why depressive symptoms are ad-
versely related to health is therefore of great importance.
The high level of symptom overlap between depression
and physical illness has been proposed as a potential reason
for the apparent association. Such hypotheses imply residual
confounding may exist, though this explanation overlooks the
potential role of somatic correlates of depression. One such
example is poor sleep [8–10].
The co-occurrence of depression and sleep symptoms has
long been recognised  though the temporal sequence has
been difficult to establish. Depression is frequently accompa-
nied by adverse changes to sleep, such as problems with sleep
onset, sleep maintenance, and early morning awakenings ;
these self-reported findings have also been confirmed using
objective readings of sleep collected via actigraphy and
polysomnography . However, despite sleep disturbance be-
ing a diagnostic characteristic of major depression, we also
know that depression is highly prevalent in those with insom-
nia  and that insomnia sufferers are at increased risk of
developing a new-onset depressive episode compared to those
without sleep problems  and such results have been sup-
ported using meta-analysis [14, 15]. Adults sleeping short
sleep hours, typically 5 h or less per night, are also at an
increased risk of depression . Abnormal sleep in turn is
associated with poor health outcomes and an array of physical
* Lydia Poole
Department of Behavioural Science and Health, University College
London, 1-19 Torrington Place, London WC1E 6BT, UK
Department of Psychology, Whitelands College, University of
Roehampton, Holybourne Avenue, London SW15 4JD, UK
International Journal of Behavioral Medicine (2018) 25:151–161
The Author(s) 2017. This article is an open access publication