Link between Schizophrenia Risk and IQ
Individuals with high intelligence may be significantly less probably to develop schizophrenia, especially those who have a genetic vulnerability to the situation. This is with respect to a new study presented in The American Journal of Psychiatry.

The scientists, which includes first author Dr. Kenneth S. Kendler, say their results challenge previous scientific studies showing that individuals who are intelligent are more probably to be mentally ill.
“If you’re genuinely smart, your genes for schizophrenia do not have much of a chance of acting,” states Dr. Kendler.
Schizophrenia is a disabling brain condition that impacts about 2.5 million individuals in the United States. Onset of the problem generally takes place in early adolescence, and it is recognized by delusions, irregular feelings, hallucinations and distressed body movements.
The actual causes of schizophrenia are not clear, but researchers have recognized that the condition is genetic; about 1% of the general population have schizophrenia, but it happens in about 10% of individuals who have have a first-degree relative – like as a parent, brother or sister – with the situation.
In this research, Dr. Kendler and co-workers set out to evaluate the connection between IQ and subsequent schizophrenia risk between the common population and those have a genetic predisposition for the condition.
Not obtaining predicted IQ ‘most powerfully predisposes for schizophrenia’
The study team assessed the IQ at ages 18-20 years of 1,204,983 Swedish men who were born in between 1951 and 1975.
The scientists applied Cox proportional hazard models to determine how IQ impacts schizophrenia risk among the common population and among cousin, half-sibling and full-sibling pairs, some of which had a relative with the situation.
Till 2010, the study team analyzed any schizophrenia-related hospital admissions among the individuals.
The outcomes of the research exposed that people with a low IQ were more probably to develop schizophrenia than those with a high IQ. This connection was most powerful among individuals with a family record of the condition; among the relative, half-sibling and full-sibling pairs, the person with the decreased IQ was at greatest threat for schizophrenia.
Leaving comments on the team’s results, Dr. Kendler states that:
“What in fact estimated risk for schizophrenia is how much you deviate from the expected IQ that we get from your family members.
If you are fairly a bit lower, that provides a high risk for schizophrenia. Not obtaining the IQ that you must have dependent on your genetic constitution and family history seems to most highly predispose for schizophrenia.”
He adds that great risk of schizophrenia connected with low IQ may be affected by environmental aspects that lower intelligence, like as early drug use or childhood trauma.
Dr. Kendler stresses, however says their outcomes do not suggest that individuals with high intelligence are not able to develop schizophrenia.
Adding to above comments Dr. Kendler says the question is may we see some upward bump at that great level of intelligence where truly brilliant individuals have enhanced risk for the disease and we show no such trend?