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A study using Collaborative Psychiatric Epidemiology Studies (CPES) to gather descriptive data from 20,013 adults reveals that the lifetime diagnosis of anxiety-related disorders for women are almost twice the lifetime diagnosis of anxiety-related disorders for men. Although females reach out for mental services more than males, males receive help from mental health professionals more than females. Studies suggest that the disproportionate rate of which women are diagnosed with anxiety may be related to the differences in cerebral metabolic rate of glucose consumption (CMRglc) in certain regions of the brain. Glucose is a source of energy for neurons, or brain cells. Neurons need glucose in order to interconnect and relay messages throughout the brain. However, levels too high of glucose metabolism may induce symptoms of mania, while levels too low of glucose metabolism may result in loss of memory, as seen in individuals with Alzheimer's disease.

Studies suggests that females have higher overall global CMRglc as well as higher CMRglc in specific regions like subcortical and cortical regions, and middle and posterior cingulate gyrus. Willis conducted research on 66 healthy and neurotypical adults, 28 female, using positron emission tomography (PET). The study controlled for risk factors such as history of mental illnesses, including family history, and used Schedule for Affective Disorders and Schizophrenia–Lifetime Version (SAD-LA) to ensure that the group of participants were neurotypical. Willis and his colleagues normalized the data to account for age differences. The study finds that although there are more similarities between females and males in terms of CMRglc, there are significant differences in subcortical and cortical regions, being that females have higher CMRglc in those regions compared to men. Gur and his colleagues used PET scans and magnetic resonance images (MRI) to compare CMRglc levels in 61 neurotypica l individuals, 24 female. The study focused on CMRglc differences during resting state, resting state being a limbo between falling asleep and being conscious. The study suggests that females have higher CMRglc in the middle and posterior cingulate gyrus. An important consideration to note is that level of glucose metabolism does not translate to anxiety symptoms, but is a good indicator of risk of anxiety-related disorders. For instance, reporting for biological or neurological differences does not equal individual report of symptoms.

Although there is research indicating neurological differences between sexes, it is unclear if the differences are innate, an effect of the environment, or a mixture of both. A study using mice observed effects of serotonin transporter on CMRglc. A specific serotonin transporter, 5-Hydroxytrypatmine (5-HT), is associated with emotional regulation in context of anxiety-related disorders. Dawson and his colleagues used prior findings on 5-HT to manipulate SERT protein, a serotonin transporter protein, in 12 wild-type mice, 6 female. The mice were decapitated 3 weeks after the manipulation and the brains were examined using autoradiogram (x-ray). The study shows that over expression of the SERT protein is more prominent in female rats compared to male rats. The study indicates that over-expression of the SERT protein, or hSERT OVR, increases the level of CMRglc in the limbic system which includes posterior cingulate and anterior cingulate. Since females have a higher tendency to over-express the gene more commonly than males, it may be an indicator of innate differences between the sexes. The Dawson study and the Willis study both mention the issue of a confound variable, menstrual cycle. The effect of the confound variable may add onto the differences in how females are more likely to experience anxiety compared to their counterpart. Gottschalk's study shows how the environment can affect biology. Gottschalk and his colleagues used PET images of 10 healthy and neurotypical males to measure CMRglc and to record verbal reports. The results suggest that upon viewing anxiety-inducing silent images, the participants had a spike in CMRglc in cortical regions as well as other regions associated with emotion, language, and sensation. In addition, the participants also reported feelings of anxiety and hostility in verbal reports. The study shows the impact of environment on biology.

Further investigation is needed to take a look at if sex differences in CMRglc directly influences anxiety symptoms. It is important to prevent the danger of drawing a causal relationship between sex and anxiety. The studies have merely shown a relationship between the two and have not claimed that increase in CMRglc causes anxiety.