Relationship between Thyroid Hormone Levels and Crime Type: A Controlled Study in Prisoners

Area of Science:

• Endocrinology
• Forensic Psychiatry
• Neurobiology

Background:

• Thyroid hormones (T3 and T4) can function as neurotransmitters, and imbalances are implicated in aggression.
• Alterations in the hypothalamic-pituitary-thyroid axis may lead to persistent aggressive behaviors, particularly in criminal populations.
• Thyroid hormone dysregulation is associated with mental and behavioral disorders.

Purpose of the Study:

• To investigate the association between elevated T3, elevated T4, and low thyroid-stimulating hormone (TSH) levels and the tendency for aggression-related crimes.
• To quantify thyroid hormone levels in incarcerated individuals.
• To explore correlations between specific hormone levels and crime rates.

Main Methods:

• A comparative study conducted in Ankara Sincan Closed Prisons involving 208 male prisoners and 82 male controls.
• Prisoners were categorized into aggression-related crime offenders (Group A, n=96) and other crime offenders (Group B, n=112).
• Measurements included pulse rates, T3, T4, TSH levels, and the T3/T4 ratio, analyzed using Wilcoxon rank sum and chi-square Fisher's exact tests.

Main Results:

• Group A exhibited significantly higher rates of toxic goitre, T3 and T4 levels, and pulse rates compared to the control group.
• Increased T3 and T4 levels, along with the presence of toxic goitre, were significantly associated with aggression-related criminal behavior.
• Statistical analysis revealed significant differences between the groups regarding these parameters.

Conclusions:

• Elevated thyroid hormone levels (T3, T4) and toxic goitre are significantly correlated with aggression-related crimes.
• Routine thyroid function examinations are recommended for prisoners, especially those convicted of violent offenses.
• Development of targeted rehabilitation and further research programs for individuals with thyroid imbalances and aggressive tendencies is warranted.