ABSTRACT
Vitamin B6 intoxication can result in a sensory ataxic neuropathy, but the association with a milder predominantly sensory or sensorimotor phenotype in chronic idiopathic axonal polyneuropathy (CIAP) remains unclear. A total of 381 patients with CIAP and 140 healthy controls were prospectively included. In a standardized fashion the use of vitamin B6 containing supplements and vitamin B6 levels were compared between patients and controls. On follow-up, patients were questioned about cessation of supplement use and the impact on the symptoms of polyneuropathy. Vitamin B6 levels in patients (median: 99 nmol/l, range: 38-2,967 nmol) were not significantly higher than in controls (median: 109 nmol/l, range: 41-2,373 nmol/l, p = 0.58), nor were daily dose, cumulative dose or duration of supplement use. However, more patients (31%) than controls (22%) used vitamin B6 containing supplements (odds ratio [OR] 1.7, 95% confidence interval [CI] 1.0-2.7, p = 0.032). Follow-up of patients confirming the cessation of supplements showed slow progression of symptoms in 64%, stabilization in 26%, and regression in 10%. On the basis of our prospective case-control study and review of the literature, an association between CIAP and vitamin B6 exposure or elevated vitamin B6 levels appears unlikely.
Subject(s)
Polyneuropathies , Vitamin B 6/adverse effects , Vitamin B 6/metabolism , Aged , Chronic Disease , Community Health Planning , Female , Follow-Up Studies , Humans , Male , Middle Aged , Polyneuropathies/chemically induced , Polyneuropathies/metabolism , Polyneuropathies/pathology , Severity of Illness Index , Surveys and QuestionnairesABSTRACT
BACKGROUND AND PURPOSE: Worldwide, different scales are used to assess the clinical condition on admission after aneurysmal subarachnoid hemorrhage. In addition to the prognostic value, the inter-rater variability should be taken into account when deciding which scale preferably should be used. We assessed the interobserver agreement of the commonly used World Federation of Neurological Surgeons, the Hunt and Hess, and the Prognosis on Admission of Aneurysmal Subarachnoid Hemorrhage scales. METHODS: In a cohort of 50 subarachnoid hemorrhage patients, 103 paired assessments were performed on the 3 admission scales by 2 independent observers per assessment with a total of 57 different raters. Patients were assessed during the first week after the hemorrhage. The interobserver agreement was calculated using quadratic (weighted) kappa statistics. RESULTS: The weighted kappa value of the Prognosis on Admission of Aneurysmal Subarachnoid Hemorrhage scale was 0.64 (95% CI, 0.49-0.79), of the World Federation of Neurological Surgeons scale was 0.60 (95% CI, 0.48-0.73), and of the Hunt and Hess scale was 0.48 (95% CI, 0.36-0.59). CONCLUSIONS: The Hunt and Hess scale showed the lowest interobserver agreement, whereas agreement of the World Federation of Neurological Surgeons and Prognosis on Admission of Aneurysmal Subarachnoid Hemorrhage scales was similar with overlapping CI.
