Frequency of obstructive sleep apnea syndrome among patients with epilepsy attending a tertiary neurology clinic.

OBJECTIVES: Epilepsy is a common neurological disorder with a median lifetime prevalence of 14 per 1000 subjects. Sleep disorders could influence epileptic seizure. The most common sleep disorder is obstructive sleep apnea syndrome (OSAS) which occurs in 2% of adult women and 4% of adult men in the general population. The aim of this study is to estimate the frequency of OSAS among patients with epilepsy and to study the seizure characteristics among those patients with co-morbid OSAS. METHODS: Patients with a confirmed diagnosis of epilepsy who attended the Sultan Qaboos University Hospital neurology clinic were recruited for the study between June 2011 and April 2012. Patients were screened for OSAS by direct interview using the validated Arabic version of the Berlin questionnaire. Patients identified as high-risk underwent polysomnography. RESULTS: A total of 100 patients with epilepsy (55 men and 45 women) were screened for OSAS. Generalized and focal seizure was found in 67% of male and 27% of female patients. Six percent of the participants had epilepsy of undetermined type. Only 9% of the sample was found to have high risk of OSAS based on the Berlin questionnaire. No significant correlation was found between risk of OSAS, type of epilepsy, and anti-epileptic drugs. CONCLUSION: The risk of OSAS was marginally greater in patients with epilepsy compared to the general population with the overall prevalence of 9%.

Reversible MRI changes in prolonged status epilepticus: a case report.

MRI is an essential investigation in epilepsy and status epilepticus (SE) for determining the underlying cause. However, SE or prolonged seizures may themselves induce changes in the MRI resulting in difficulty in interpretation. This case report illustrates a patient who recovered completely from prolonged generalized idiopathic SE lasting more than 2 weeks and had transient bilateral external capsule, fronto-temporal, and insular cortical MRI changes. The mechanism of such MRI changes and their implications for survival even after prolonged SE are discussed.

Age-specific progression of nigrostriatal dysfunction in Parkinson's disease.

OBJECTIVE: To investigate in vivo the impact of age on nigrostriatal dopamine dysfunction in Parkinson's disease (PD). METHODS: PD patients (n = 78) and healthy control subjects (n = 35) underwent longitudinal positron emission tomography assessments using 3 presynaptic dopamine markers: (1) [¹¹C](±)dihydrotetrabenazine (DTBZ), to estimate the density of the vesicular monoamine transporter type 2; (2) [¹¹C]d-threo-methylphenidate, to estimate the density of the plasma membrane dopamine transporter; and (3) 6-[¹8F]-fluoro-L-dopa, to estimate the activity of the enzyme dopa-decarboxylase. RESULTS: The study comprised 438 PD scans and 241 control scans (679 scans in total). At symptom onset, the loss of putamen DTBZ binding was substantially greater in younger compared to older PD patients (p = 0.015). Remarkably, however, the rate of progression of DTBZ binding loss was significantly slower in younger patients (p < 0.05). The estimated presymptomatic phase of the disease spanned more than 2 decades in younger patients, compared to 1 decade in older patients. INTERPRETATION: Our results suggest that, compared to older patients, younger PD patients progress more slowly and are able to endure more damage to the dopaminergic system before the first motor symptoms appear. These observations suggest that younger PD patients have more efficient compensatory mechanisms.

Apparently persistent weakness after recurrent hypokalemic paralysis: a tale of two disorders.

A 19-year-old woman presented with recurrent hypokalemic paralysis, followed by apparently persistent symptoms due to coexisting osteomalacia. Distal renal tubular acidosis type 1 (dRTA1) linked the metabolic abnormalities and occurred as an extraglandular feature of Sjögren syndrome (SS). This case highlights the fact that in the setting of recurrent hypokalemia, apparently progressive weakness should be distinguished from primary hypokalemic paralysis and evaluated for dRTA1, as the metabolic alterations are potentially treatable. Further dRTA1 may precede the occurrence of sicca syndrome in SS.