Exploratory study of ultraviolet B (UVB) radiation and age of onset of bipolar disorder.

BACKGROUND: Sunlight contains ultraviolet B (UVB) radiation that triggers the production of vitamin D by skin. Vitamin D has widespread effects on brain function in both developing and adult brains. However, many people live at latitudes (about > 40 N or S) that do not receive enough UVB in winter to produce vitamin D. This exploratory study investigated the association between the age of onset of bipolar I disorder and the threshold for UVB sufficient for vitamin D production in a large global sample. METHODS: Data for 6972 patients with bipolar I disorder were obtained at 75 collection sites in 41 countries in both hemispheres. The best model to assess the relation between the threshold for UVB sufficient for vitamin D production and age of onset included 1 or more months below the threshold, family history of mood disorders, and birth cohort. All coefficients estimated at P ≤ 0.001. RESULTS: The 6972 patients had an onset in 582 locations in 70 countries, with a mean age of onset of 25.6 years. Of the onset locations, 34.0% had at least 1 month below the threshold for UVB sufficient for vitamin D production. The age of onset at locations with 1 or more months of less than or equal to the threshold for UVB was 1.66 years younger. CONCLUSION: UVB and vitamin D may have an important influence on the development of bipolar disorder. Study limitations included a lack of data on patient vitamin D levels, lifestyles, or supplement use. More study of the impacts of UVB and vitamin D in bipolar disorder is needed to evaluate this supposition.

Periodic Catatonia: Long-term Treatment With Lamotrigine: A Case Report.

Periodic catatonia is a rare form of catatonia, characterized by episodes occurring in a cyclic pattern with clinical features of combined stupor and excitement, with intervals of remission. Although periodic catatonia is not common, it is an urgent condition, requiring hospitalization for evaluation and treatment. The management of periodic catatonia is quite challenging, mainly because of the unknown pathophysiological mechanisms involved in the onset of this clinical entity, which are less clear than in other forms of catatonia. Although positive trials of several medications in the acute phase of periodic catatonia have been published, available literature concerning the prevention of recurrent catatonic episodes is scarce. Here, we present the case of a patient with periodic catatonia in which long-term treatment with lamotrigine appears to have acted prophylactically in reducing the occurrence and severity of new catatonic episodes. A better understanding of the mechanisms involved in the pathophysiology of periodic catatonia and increasing psychiatrists' and physicians' awareness of the presentation of this clinical entity could be of benefit in shedding light on the most appropriate treatment approach. However, further clinical studies are needed before any firm recommendations can be made.

Preoperative neuropsychological presentation of patients with refractory frontal lobe epilepsy.

BACKGROUND: This study investigated whether certain cognitive deficits are associated with frontal lobe epilepsy (FLE) aiming to contribute with localization data to the preoperative assessment of epilepsy surgery candidates. METHODS: We evaluated 34 patients with refractory FLE, 37 patients with refractory medial temporal lobe epilepsy (MTLE), and 22 healthy individuals in attention, psychomotor speed, motor function, verbal memory span, verbal fluency, response inhibition/interference, concept formation and set shifting, anticipation and planning, global memory. RESULTS: Neuropsychological performances of FLE and MTLE were similar, with the only exception the WCST-number of categories index, measuring mental flexibility, in which MTLE patients performed significantly worse than FLE patients. Left-FLE patients presented more perseverative responding compared to both other patient groups and healthy controls (HCs), while left-MTLE patients showed worse sorting abilities than the other epilepsy groups. CONCLUSIONS: Our findings suggest a weak cognitive differentiation between FLE and MTLE, probably attributed to the intricate nature of fronto-temporal connectivity frequently resulting in overlapping deficits as well as the confounding effects of seizure-related variables. In clinical practice, a highly individualized (idiographic) neuropsychological approach along with the inclusion of concurrent EEG recordings (e.g., interictal coupling) may be of help for neuropsychologists in identifying FLE patients from those with medial temporal pathology presenting frontal dysfunction as a secondary cognitive symptom.