blood-cerebrospinal fluid barrier: a cross-sectional study
http://www.ehjournal.net/content/8/1/19
Abstract
Background: Whether low-intensity radiofrequency radiation damages the
blood-brain
barrier has long been debated, but little or no consideration has
been given to the
blood cerebrospinal fluid barrier. In this cross-sectional study we
tested whether long-term and/or
short-term use of wireless telephones was associated with changes in the
serum transthyretin
level, indicating altered transthyretin concentration in the
cerebrospinal fluid, possibly
reflecting an effect of radiation.
Methods: One thousand subjects, 500 of each sex aged 18-65 years, were
randomly recruited
using the population registry. Data on wireless telephone use were
assessed by a postal
questionnaire and blood samples were analyzed for serum
transthyretin concentrations
determined by standard immunonephelometric techniques on a BN Prospec®
instrument.
Results: The response rate was 31.4%. Logistic regression of
dichotomized TTR serum
levels with a cut-point of 0.31 g/l on wireless telephone use yielded
increased odds ratios that
were statistically not significant. Linear regression of time since first
use overall and on the
day that blood was withdrawn gave different results for males and
females: for men
significantly higher serum concentrations of TTR were seen the longer an
analogue telephone
or a mobile and cordless desktop telephone combined had been used,
and in contrast,
significantly lower serum levels were seen the longer an UMTS
telephone had been used.
Adjustment for fractions of use of the different telephone types did not
modify the effect for
cumulative use or years since first use for mobile telephone and
DECT, combined. For
women, linear regression gave a significant association for
short-term use of mobile and
cordless telephones combined, indicating that the sooner blood was withdrawn
after the most
recent telephone call, the higher the expected transthyretin concentration.
Conclusions: In this hypothesis-generating descriptive study time since
first use of mobile
telephones and DECT combined was significantly associated with
higher TTR levels
regardless of how much each telephone type had been used.
Regarding short-term use,
significantly higher TTR concentrations were seen in women the sooner blood
was withdrawn
after the most recent telephone call on that day.
