How Sex Hormones Dominate the Attack of Neurodevelopmental/Neurodegenerative Diseases

Biological Differences Affect CNS-related Disease Attack

The Pin & Needle Effect of MS

Human anatomy remains the same in men and women and it’s the underlying cognitive skills and behavior that show great variations. Its always been a topic of conflict whether these variations have a biological background or are the expression of societal influences. Its been evident from certain studies that there are sex differences in the brain that exist as the basis for male- or female-specific behaviors. The concept can be extended to neuroanatomy, neurochemistry and neuronal structure which are influenced by the presence of gonadal sex steroids. Science has shown a clear-cut bias towards males in the case of developmental onset disorders such as autism spectral disorders and ADHD while adult onset disorders are biased towards females. Trauma-related disorders, stress and anxiety disorders and autoimmune diseases affecting the nervous system exhibit stark differences between the male and female population.
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Neurodevelopmental Disorders
Autism spectral disorder (ASD) is a classic example of male-dominant neurodevelopmental disorder having a sex ratio of 4:1 (male: female). Autism is predominantly a genetic disorder but having no direct link with the sex chromosome. It could be that genes on the Y chromosome interact with the ASD susceptibility gene and influence the occurrence of the disorder in the male population. Another hypothesis is that, ASD is diagnosed more in boys compared to girls as it might be underdiagnosed because of female-specific characters in the girl. Girls communicate in a better way and are also better at expressing non-verbally too both of which might increase the chances of underdiagnosing the condition.

According to the extreme male brain (EMT) theory brain is adaptive to male and female cognitive profiles in two domains namely empathizing (respond to emotions) and systemizing (ability to analyze). The female population is inclined towards empathizing compared to males but individuals with autism exhibit too much of the male profile. A study of 2500 children affected by autism tried to analyze this theory and found that such females had greater social communication impairment, lesser cognitive skills and decreased ability to adapt compared to males. Memory problems were more seen in males while the female gender was better at retrieving memory details. But there are other studies that did not find any gender variations in autism-related symptoms, adaptive skills, developmental adaptability and behavior problems.

Affective Disorders
Stress is universal, but women are greatly attracted to it just like a magnet. Mood and anxiety disorders perfectly exhibit the bias towards females. Women are two-times at a higher risk of suffering from anxiety disorders, stress-related problems and depression compared to males. There are evident biological processes that seem to greatly contribute towards this bias in terms of genetic vulnerability, female hormones that fluctuate owing to reproductive functions and brain’s reaction to such fluctuations that induce depression. Social and environmental factors such as the role of women in everyday life, sex-specific socialization and the secondary role they play all contribute towards greater stress in a woman’s life.

While depression can strike anytime a woman is at a higher risk of depression during different phases of a reproductive cycle-before menstruation time, during pregnancy, after childbirth and after menopause. Adding to this are events such as infertility, miscarriage, oral contraceptives and hormone replacement therapy.

Statistics show that 80% of seasonal affective disorder (SAD) cases are in females. SAD is generally due to impairment of the hypothalamus-pituitary-adrenal (HPA) axis. Most depressive disorders occur due to differences in HPA functioning.

Neurodegenerative Disease
Parkinson’s Disease (PD): Men are generally predisposed to PD, almost .5 times more compared to women. Also, symptoms such as nervousness, fatigue, constipation and restless leg were greater in women while sexual dysfunction, daytime sleep and frequent saliva dribbling were common in men.

Alzheimer’s Disease (AD): AD is seen more in women. There are different reasons given to this and one major reason is the longer life tenure of women which puts them at an increased risk of AD. There are biological reasons also given in terms of age-related decrease in sex hormone (estrogen, progesterone and testosterone), the impact from increased risk of other diseases such as diabetes and cardiovascular disease and brain-glucose metabolism. Even after controlling for increased life span women exhibited a faster and greater deterioration of cognition with age than men. Go to www.firsteatright.com for a detailed description AD, why it attacks women predominantly and how to help people with AD lead as normal a life as possible.

Multiple Sclerosis (MS): While women are at a greater risk of MS, men go through a worse experience if MS attacks them. Studies show that hormonal factors influence disease onset and the course of the disease. White matter was greatly affected in male MS patients and this also indicates that white matter might play a sex-specific role in cognitive dysfunction in MS.

Pain: You would have guessed it right-its women who exhibit greater response to pain. A small hurt, a sign of blood or a spasm and women suffer from extreme pain while most men take it in their stride and keep moving on. Studies show that chronic pain conditions such as migraine, tension headache and fibromyalgia are profoundly intense in women comparatively. When researchers scrutinized the role of sex hormones in pain they came up with the following. Estradiol and progesterone allow and block the effect of pain while testosterone appears to block the pain effect and remains protective.

Social and environmental pressures also seem to influence the reaction shown by males and females in response to pain. Its acceptable for a woman to exhibit pain while men who exhibit their pain for every small hurt or problem are considered less-masculine. This might be the reason why women show greater pain and agony compared to men.

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