Symptoms 'unexplained by organic disease' in 1144 new neurology out-patients: how often does the diagnosis change at follow-up?

Stone, J. et al. (2009) Symptoms 'unexplained by organic disease' in 1144 new neurology out-patients: how often does the diagnosis change at follow-up? Brain, 132(10), pp. 2878-2888. (doi: 10.1093/brain/awp220)

Abstract

It has been previously reported that a substantial proportion of newly referred neurology out-patients have symptoms that are considered by the assessing neurologist as unexplained by ‘organic disease’. There has however been much controversy about how often such patients subsequently develop a disease diagnosis that, with hindsight, would have explained the symptoms. We aimed to determine in a large sample of new neurology out-patients: (i) what proportion are assessed as having symptoms unexplained by disease and the diagnoses given to them; and (ii) how often a neurological disorder emerged which, with hindsight, explained the original symptoms. We carried out a prospective cohort study of patients referred from primary care to National Health Service neurology clinics in Scotland, UK. Measures were: (i) the proportion of patients with symptoms rated by the assessing neurologist as ‘not at all’ or only ‘somewhat explained’ by ‘organic disease’ and the neurological diagnoses recorded at initial assessment; and (ii) the frequency of unexpected new diagnoses made over the following 18 months (according to the primary-care physician). One thousand four hundred and forty-four patients (30% of all new patients) were rated as having symptoms ‘not at all’ or only ‘somewhat explained’ by ‘organic disease’. The most common categories of diagnosis were: (i) organic neurological disease but with symptoms unexplained by it (26%); (ii) headache disorders (26%); and (iii) conversion symptoms (motor, sensory or non-epileptic attacks) (18%). At follow-up only 4 out of 1030 patients (0.4%) had acquired an organic disease diagnosis that was unexpected at initial assessment and plausibly the cause of the patients’ original symptoms. Eight patients had died at follow-up; five of whom had initial diagnoses of non-epileptic attacks. Seven other types of diagnostic change with very different implications to a ‘missed diagnosis’ were found and a new classification of diagnostic revision is presented. One-third of new neurology out-patients are assessed as having symptoms ‘unexplained by organic disease’. A new diagnosis, which with hindsight explained the original symptoms, rarely became apparent to the patient's primary care doctor in the 18 months following the initial hospital consultation.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Error, Mr Roderick and Walker, Ms Jennifer and McMahon, Dr Alex and Cavanagh, Professor Jonathan
• Authors: Stone, J., Carson, A., Duncan, R., Coleman, R., Roberts, R., Warlow, C., Hibberd, C., Murray, G., Cull, R., Pelosi, A.J., Cavanagh, J., Matthews, K., Goldbeck, R., Smyth, R., Walker, J., McMahon, A.D., and Sharpe, M.
• College/School: College of Medical Veterinary and Life Sciences > School of Health & Wellbeing > Mental Health and Wellbeing; College of Medical Veterinary and Life Sciences > School of Medicine, Dentistry & Nursing > Dental School
• Journal Name: Brain
• Publisher: Oxford University Press
• ISSN: 0006-8950
• ISSN (Online): 1460-2156
• Published Online: 08 September 2009