Medıcıne elsewhere

Marmara Medical Journal Volume 12 No: 2 April 1999

MEDICINE ELSEWHERE

Dilek Tiryaki M.D.

L ask y T, T e rra c c ia n o G J, M a g d e r L, et at. T h e G u lla in -B a rre s y n d ro m e an d th e 1 9 9 2 -1 9 9 3 an d 1 9 9 3 -1 9 9 4 In flu e n z a v a c c in e s . N E n g l J M ed 1 9 9 8 ;3 3 9 :1 7 9 7 -1 8 0 2 .

T he number of reports of influenza vaccine-associated G u illain -B arre syndrom e to the national V accin e Adverse Event Reporting System increased from 3 7 in 1 9 92 -199 3 to 74 in 1 9 93 -199 4, arousing concern about a possible increase in vaccine-associated risk. The Guillian-Barre syndrome is characterized by loss of reflexes and symm etric paralysis, usually beginning in the legs, which is mediated by an im m une response that results in the direct destruction of either the myelin sheath surrounding the peripheral nerves or the axon itself. Among the vaccines reported to be associated with the onset of the G uillian-Barre syndrome are the swine influenza (A /N e w Jersey) vaccine in 19 7 6 -1 9 7 7 , oral polio vaccine, and tetanus toxoid. T he association with the A /N e w Jersey swine influenza vaccine w as notable for relative risks of Guillain-Barre syndrome ranging from 4.0 to 7 .6 for 6 to 8 w eeks periods after vaccination.

In this study, the patients given a diagnosis of the Guillain- Barre syndrome in the 1 9 9 2 -1 9 9 3 and 1993- 1994 influenza-vaccination seasons w ere identified from the hospital discharge data bases of four states. Disease with an onset within 6 w eeks after vaccination was defined as vaccine-associated. 180 of 273 adults with the Guillain-Barre syndrome w ere interviewed. The vaccine providers confirmed influenza vaccination in the six w eeks before the onset of the Guillain-Barre syndrome for 19 patients. T he relative risk of the Guillain-Barre syndrome associated with vaccination, adjusted for age, sex, and vaccine season, w as 1.7. The adjusted relative risks w ere 2 .0 for the 1 9 9 2 -1 9 9 3 season and 1.5 for the 1 9 9 3 -1 9 9 4 season. In 9 of the 19 vaccine-associated cases, the onset w as in the second w eek after vaccination, all betw een day 9 and day 12.

T h e re w as no in c re a s e in th e risk of vaccin e- associated G uillain-Barre syndrom e from 1 9 9 2 -1 9 9 3 to 1 9 9 3 -1 9 9 4 . For the two seasons com bined, the adjusted relative risk of 1.7 suggests slightly more than one additional case of G uillain-Barre syndrom e per million persons vaccinated against influenza.

J o h n s o n DL, W ie b e JS , G o ld S M . et al. C e re b ra l b lo o d flo w an d p e rs o n a lity : A p o s itro n e m is s io n to m o g ra p h y s tu d y . A m J P s y c h ia try 1 9 9 9 ;1 5 6 .2 5 2 - 257.

T h e objective of this study w as to describe brain regions associated with the personality dimension of introversion / extroversion. M ost major current models of personality include the dim ension of introversion / extroversion at a fundam ental level. At one end of the introversion / extroversion continuum are extroverts, who are described as gregarious, socially active, cheerful, assertive, and easily excitable. At the other end of the spectrum are introverts who tend to be reclusive and quiet, preferring books to other people. Introverts have higher cortical activity then extroverts, especially in the frontal lobes.

In this study 18 healthy individuals (10 m ale and 8 fem ale) recruited from the com m unity w ere studied. Introversion / extroversion scores w ere taken from the N E O Five-Factor Inventory, a 60-item abbreviated form of the NE o Personality Inventory-Revised. Men and w om en did not differ significantly in term s of extroversion scores. M easu res of cerebral blood flow w e re o b tain ed by m e an s of positron em ission tom ography. T h e re w ere eight regions correlated with introversion and seven correlated with extroversion. Regions showing a relationship with introversion had a larger volum e than did regions cerebral blood flow with introversion / extroversion w e re calculated, and a three-dim ension al m ap of th ose correlations w as generated. Introversion w as associated with increased blood flow in the frontal lobes and in the anterior thalam us. Regions in the anterior with extroversion. T h e findings of this study lend support to the notion that introversion is associated with increased activity in th e frontal lobe regions. M o re o v e r, the study suggested that individual differences in introversion and extroversion are related to differences in a fronto- striato-thalam ic circuit.