✔ Multiple sclerosis: In this disease, the outer coating of nerve cells, called myelin, is deficient in some parts of the nervous system, which means that messages carried by the nerves aren’t transmitted as well as they should be and may not get through at all. If the nerves affected are in the cortex of the brain, which is where most of the ‘clever’ functions people perform are carried out, patients can develop cognitive symptoms including forgetfulness and difficulty with problem solving.
✔ Normal pressure hydrocephalus: The brain and spinal cord are surrounded by cerebrospinal fluid, which supplies nutrients and acts as a shock absorber to protect the nervous system from damage during trauma. People with hydrocephalus have too much of this fluid, and it begins to damage nerve cells because of the increased pressure. Normal pressure hydrocephalus usually begins to develop in people aged 55 to 60.
The damage that normal pressure hydrocephalus causes in the brain produces symptoms similar to those of dementia, accompanied by difficulties with walking and urinary incontinence. Treatment involves fitting a shunt in the brain to allow the fluid to drain. If the treatment is carried out early in the disease process, the success rate for resolving symptoms is at least 80 per cent.
✔ Creutzfeldt–Jakob disease (CJD): This fatal brain disease is, thankfully, rare. It has four types, the most well-known being variant Creutzfeldt–Jakob disease. This version of the disease is believed to be linked to bovine spongiform encephalopathy, better known as BSE or, in tabloid headlines, mad cow disease.
CJD is contagious and is transmitted by an infectious protein called a prion. Once inside the body, prions rapidly destroy brain tissue, leading to death within a year. Symptoms of this awful disease include dementia, unsteadiness, slurring of speech, loss of bladder control and blindness.
✔ Huntington’s disease: Another of nature’s most unpleasant diseases, Huntington’s disease is hereditary and is caused by a defect on chromosome 4. If one parent has the disease, a couple’s children have a 50:50 chance of inheriting the condition. Symptoms don’t develop until middle age, but once they do the disease progresses relentlessly until death. Alongside dementia, sufferers develop jerking movements of their limbs and changes in mood and personality.
Hormonal and nutritional causes
The following conditions are generally not as devastating as the neurological conditions described in the preceding section. Many of the symptoms caused by these conditions are reversible with the correct treatment. Hormonal and nutritional causes of dementia include:
✔ Addison’s and Cushing’s disease: These conditions, named after the doctors who first discovered them, both affect the levels of a hormone called cortisol. In Addison’s not enough cortisol is produced; in Cushing’s too much. The knock-on effect of these altered cortisol levels is a corresponding upset in the levels of some of the minerals in the blood stream, most notably sodium and potassium, which leads to confusion. Thankfully, by treating the underlying cause, the confusion is reversible.
✔ Diabetes: One of the most common reasons for doctors seeing people who are acutely confused is that their blood sugar levels are either too low or too high. Neither situation is particularly good for people, but when their blood sugar is adjusted, their confusion quickly fades.
✔ Thyroid disease: Thyroxine is a hormone produced in the thyroid gland, which sits at the front of the neck. In simple terms, this hormone is involved in metabolism within the body: too much and everything in the body is in a rush (the heart races, diarrhoea develops and people become agitated); too little and everything slows down (pulse is slow, people gain weight, skin becomes dry, hair falls out and they can become constipated). Both an under- and over-active thyroid can cause confusion. In both cases, the confusion can again be reversed by treating the underlying cause.
✔ Hyperparathyroidism: The parathyroid glands are pea sized and sit just behind the thyroid gland in the neck. The hormone they produce – parathyroid hormone – is involved in controlling levels of calcium, phosphate and vitamin D. If the gland becomes overactive, levels of calcium in the blood shoot up. Too much calcium can affect personality and consciousness, cause disorientation and, if not corrected quickly enough, coma. Treatment is curative.
✔ Vitamin B12 deficiency: This vitamin, found in fish, poultry, eggs and dairy products, is absorbed in the gut during digestion with the help of a protein called intrinsic factor. Some people either don’t make enough of this protein or have a condition that destroys it. As a result, they don’t absorb vitamin B12. One of the roles of this vitamin is ensuring healthy nerve function. A lack can cause numbness and tingling in the hands and feet and, if significant, mood changes and poor memory. Treatment by injection of vitamin B12 avoids the problem of lack of stomach absorption and can improve symptoms.
Alcohol-related causes
Indulging in more than the advised levels of society’s favourite drug more often than recommended will reveal it to be the poisonous substance it truly is. The effects on the body are wide-ranging and it can wreak havoc on a number of our internal organs, but it’s the problems it can cause in the liver and brain that mimic dementia.
✔ Cirrhosis: Liver cells can be damaged by alcohol. The liver can also be affected by viruses such as hepatitis and an autoimmune condition in which the immune system, rather than an infection, attacks the body. Such damage stops the liver working as it should do, which, among other things, leads to the build-up of toxic waste products in the blood. When these toxins build up they can damage brain cells, leading to encephalopathy, which encompasses a collection of symptoms like confusion, poor memory, personality change and inappropriate behaviour. Occasionally, encephalopathy can be reversed by treating the liver damage, but it can prove fatal.
✔ Korsakoff’s syndrome: Another condition named after the doctor who discovered it, Korsakoff’s syndrome is most often seen in alcoholics in whom high alcohol intake stops the absorption of a B vitamin called thiamine. Thiamine is needed for normal nerve cell function, and insufficient levels commonly cause people to develop memory problems and changes in personality. This condition can be treated by quitting the booze and taking a thiamine supplement.
Infectious causes
Many infections can produce acute confusion, especially in the elderly. This confusion can be caused by the direct effect of viruses or bacteria on the brain, the toxins they produce in the blood stream, or the more general effects of infection on the body, from high temperature to dehydration. The most common infections that can cause confusion – or to give it its more glamorous-sounding, old-fashioned name, delirium – are
✔ Urinary tract infections such as cystitis (affecting the bladder) and pyelonephritis (affecting the kidneys)
✔ Chest infections, from bronchitis to full-on pneumonia
✔ Severe viral infections like influenza
✔ Infections that directly affect the brain, such as meningitis (which affects the meninges covering the central nervous system) or encephalitis (which affects brain cells)
Prescription medication causes
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