Prevalence of depression in amyotrophic lateral sclerosis/motor neuron disease: multi-attribute ascertainment and trajectories over 30 months

Abstract

Objective: Evidence is equivocal about the prevalence of depression in amyotrophic lateral sclerosis (ALS). This study uses a multi-attribute ascertainment of the prevalence of depression and examines this prevalence over time. Methods: Patients with ALS were recruited into the Trajectories of Outcome in Neurological Conditions (TONiC-ALS) study. Caseness was identified by the Modified-Hospital Anxiety and Depression Scale (M-HADS). In addition, participants provided data on co-morbidities and medication use. A combination of the three was used to derive the estimate for the prevalence of depression, treated or untreated. Longitudinal data were analyzed by trajectory analysis of interval level M-HADS-Depression data. Results: Among 1120 participants, the mean age was 65.0 years (SD 10.7), 60.4% male, and the median duration since diagnosis was 9 months (IQR 4–24). Caseness of probable depression at baseline, defined by M-HADS-Depression, was 6.45% (95%CI: 5.1–8.0). Taken together with antidepressant medication and co-morbidity data, the prevalence of depression was 23.1% (95%CI: 20.7–25.6). Of those with depression, 17.8% were untreated. Trajectory analysis identified three groups, one of which contained the most cases; the level of depression for each group remained almost constant over time. Conclusion: Depression affects almost a quarter of those with ALS, largely confined to a single trajectory group. Prevalence estimates based on screening for current depressive symptoms substantially under-estimate the population experiencing depression. Future prevalence studies should differentiate data based on current symptoms from those including treated patients. Both have their place in assessing depression and the response by the health care system, including medication, depending upon the hypothesis under test.

Keywords:

• Amyotrophic lateral sclerosis
• antidepressants
• depression prevalence
• epidemiology
• models
• modified-hospital anxiety and depression scale
• prognostic
• trajectories of outcome in neurological conditions (TONiC-ALS)

Acknowledgments

We sincerely thank all the people with ALS/MND and their families who contributed to this study; staff from MND Care Centres in Basildon, Brighton, Cambridge, Cumbria, Dartford & Gravesham NHS Trust, Edinburgh, Exeter, Kings’ College London, Leicester, Liverpool, London North West, London, North East, Maidstone, Manchester, Newcastle, North Devon, Norwich, Oxford, Peterborough, Portsmouth, Plymouth, Preston, Sheffield, Shropshire, Southampton, South Wales MND Care Network (Cardiff, Swansea, Cwm Taf and Hywel Dda Clinics), Stoke on Trent, Swansea, West Suffolk, Worcester for identifying and caring for study patients; the research and clinical staff for recruitment and data collection; and the TONiC team. We thank NIHR Clinical Research Network and the NIHR UK MND Clinical Studies Group for support.

Declaration of interest

The authors report no conflicts of interest. No funding source had involvement in the study design, analysis, interpretation of data, or preparation of the manuscript.

Additional information

Funding

This work was supported by the Motor Neurone Disease Association (UK) under grant Young/Jan15/929-794, and also received research support from the NIHR Clinical Research Network, and the Neurological Disability Fund 4530. AAC is an NIHR Senior Investigator and is supported through the following funding organizations under the egis of JPND – www.jpnd.eu (United Kingdom, Medical Research Council (MR/L501529/1; MR/R024804/1) and Economic and Social Research Council (ES/L008238/1)) and through the Motor Neurone Disease Association. This study represents independent research part-funded by the National Institute for Health Research (NIHR) Biomedical Research Center at South London and Maudsley NHS Foundation Trust and King’s College London. CJM and this research are supported by the NIHR Sheffield Biomedical Research Center and the NIHR Sheffield Clinical Research Facility. CAY and this research are supported by NIHR CRN NWC.