Neuropsychiatric symptoms in patients with multiple sclerosis
Figved N, Klevan G, Myhr KM, Glad S, Nyland H, Larsen JP, et al. ;
Commented by , 17 Jan 2006
Background
Multiple Sclerosis (MS) is not normally regarded as a psychiatric condition, of either younger or older people. Historically, care of people with MS has been by neurologists; neurological skills are required at the time of diagnosis, which is often a complex process.
However, a demyelinating condition is bound to have neuropsychiatric sequelae and/or to cause cognitive impairment in some cases and the "psychiatric component" of MS is not prominent in the literature. This paper highlights the prevalence of depression and frontal signs such as apathy and irritability in MS.
Objective
To quantify psychiatric symptoms in recently diagnosed patients with MS, and examine any link between psychiatric symptoms and neurological disability.
Methods
All patients diagnosed with MS by neurologists between 1998 and 2000 in two hospitals in Western Norway were invited to participate.
Psychiatric assessment was performed by a psychiatrist or a research nurse, who knew the diagnostic category, but not the level of disability of participants who they administered the 12-item Neuropsychiatric Inventory (NPI), within one month of the neurology appointment in 90% of cases.
40 patients attending an out-patient clinic with systemic lupus erythematosis acted as controls and had an identical assessment.
NPI scores were analysed between patients and controls using a range of parametric and non-parametric statistics.
Results
Of 93 patients diagnosed with MS, 86 (25 males, 61 females) agreed to participate. Mean age was 42 years, mean duration of symptoms was 8½ years, and mean duration since diagnosis 2½ years.
90% had a remitting-relapsing course, of whom 13% converted to a secondary progressive course; 10% had a primary progressive course, consistent with patterns of MS reported elsewhere in the literature.
35 patients had had short courses of steroids, 7 interferon therapy, but only 3 had had antidepressants. Of the control group with SLE, 27/40 (68%) had received steroids.
Patients with MS had significantly more symptoms on the NPI than controls in total and subscale comparisons. The most frequent symptoms were depression (59%), sleep disturbance (48%), irritability/emotional lability (42%) and apathy (31%).
Psychotic symptoms were infrequent. A trend toward correlation, not reaching statistical significance, was found between total NPI score and duration of disease. High level of disability was associated with high NPI depression subscore, but not with total NPI score or other NPI subscores.
Dr Seymour's comments
The main finding of this study was that 80% of MS patients had at least one psychiatric symptom, many had several symptoms and scored on average higher on the NPI scale than controls with SLE. The increased prevalence of depressive symptoms is of significance because depression is potentially associated with poor outcome in MS.
From the methodological perspective, this study has limitations in terms of its cross-sectional design, sample size, and limited psychiatric assessment. However, it alerts clinicians, particularly neurologists and general practitioners, of the need to be aware of psychiatric symptomatology in their community-based patients with MS, particularly depression, apathy and irritability.
As these symptoms are more prevalent than in similarly-disabled controls with non-neurological disease, they are likely to arise from organic brain disease rather than psychosocial factors.