Possessing one or another version of a gene key to
metabolizing the B vitamin folate may make a big difference
in who responds to vitamin supplements intended to treat
negative symptoms of schizophrenia, according to a new
study. Researchers tracked 140 people with schizophrenia for
16 weeks and found that those with the so-called
high-functioning FOLH1 gene variant had a greater response
to folic acid and B12 supplements, compared to those with
the low-functioning FOLH1 variant. "That's a gene that
actually controls the digestion of folate (or folic acid)
into the bloodstream," said the study's lead author. Folate,
one of the B vitamins, is used in the manufacturing of
neurotransmitters, which send signals throughout the brain
and body, and it's found in leafy vegetables, citrus fruits,
beans and fortified grain products. Since the 1960s, folate
deficiencies have been tied to the development of
schizophrenia, and researchers have observed spikes in cases
of the mental disorder after famines in China and the
Netherlands, for example. But this new study, researcher
said, is the first to look at the effects of folate
supplements in a large population of people with the
condition - at several medical centers in Massachusetts, New
York and Michigan. The researchers, who published their
findings in JAMA Psychiatry, were targeting so-called
negative symptoms in schizophrenia patients, which include
apathy, withdrawal and an inability to display emotion.
Those are less severe than the more well-know symptoms of
schizophrenia - including hallucinations, delusions and
paranoia - but still lead to significant impairment, because
they are unaffected by traditional antipsychotic drugs,
experts said. For the new study, the researchers recruited
140 schizophrenia patients and randomly assigned them into
two groups. One group received 2 milligrams of folic acid
and 400 micrograms of vitamin B12, which increases folic
acid's effect, per day for 16 weeks. The other group took
placebo pills for comparison, but all patients also
continued their normal medications. At the beginning, each
group scored in the mid-30s on a scale that measures the
severity of their negative symptoms from 0 to 100 - with
higher scores being more severe. Researcher said the
participants all had moderate to severe symptoms. Overall,
those taking the supplements improved on the scale after the
16 weeks, but it wasn't until the researchers looked at each
person's FOLH1 gene type that they identified who benefited
the most. Specifically, those with the high-functioning
version of the FOLH1gene seemed to be able to process the
supplements best, and saw their negative symptom score drop
by about 5 points, compared to no significant change in the
placebo group members with high-functioning FOLH1 genes.
Folate levels in people with the low-functioning variant who
took the supplements eventually caught up to those with the
high-functioning variant, according to the study. And those
participants might have improved on the symptom scale if the
study had gone longer than 16 weeks. |