Developing countries thiamin deficiency

Thiamin (Vitamin B-1). It is well known that people suffering from severe thiamin deficiency, or beriberi, may die suddenly from heart failure. However, this severe deficiency is not often seen in the developed countries, except in certain alcoholics who eat poor diets. Also, hospital patients given only intravenous glucose (sugar) solutions without supplementary thiamin and other vitamins may develop severe thiamin deficiencies when such treatment lasts for prolonged periods of time (1 to 2 weeks). 

Nutritional Deficiency-Related Dementias. We have already mentioned that chronic alcoholics are subject to thiamine deficiency that can cause dementia. It usually occurs only after heavy, prolonged abuse of alcohol. In developed countries, the other key nutritional concern is vitamin deficiency. Vitamin deficiency can surprisingly strike even those with a healthy diet. Such people are missing a vital protein, intrinsic factor, which would enable them to absorb it from their digestive tract. 

Although now largely eradicated, beriberi remains a problem in some parts of the world among people whose diet is especially high in carbohydrates. A different condition, affecting the central rather than peripheral nervous system, the Wemicke-Korsakoff syndrome, is also due to thiamin deficiency. It occurs in developed countries, especially among alcoholics and narcotic addicts. 

A minority of alcoholics develop nutrient deficiencies. In Western countries, alcoholics represcrit the largest population segment that can benefit from dietary intervention. Alcoholics are at risk for deficiencies in folate, thiamin, riboflavin, vitamin B, vitamin A, and magnesium, particularly when the intake of these substances is low. In some cases, absorption of the nutrient is impaired in others, catabolism of the nutrient is iitcreased. Thiamin deficiency is a firmly established consequence of alcoholism, as discussed in the iTiiamin section. 

Thiamin is a water-soluble vitamin. The RDA of thiamin for the adult man is 1.5 mg. The vitamin is present in a variety of foods of plant and aiumal origin, as well as in yeast. The populations most at risk of developing a deficiency are chronic alcoholics in Western countries and those with an overdeptendence on polished rice as a staple in underdeveloped nations. The consumption of large amounts of raw seafood can also induce the deficiency. Thiamin deficiency in humans is called beriberi. The disease occurs in a variety of forms and causes different problems in infants, adults, and alcoholics. 

The use of oral contraceptive agents (OCAs) is widespread and is being increasingly encouraged in developing countries. Their use has been associated with a number of side effects, in particular, a possible increased risk of thrombotic and embolic vascular disease. There is also evidence that OCAs may affect the metabolism of a number of vitamins. Evidence for deficiency of thiamine, riboflb vin, ascorbic acid, pyridoxine, folic acid, and vitamin B12, and for excess accumulation of vitamin A has been reported. This is of particular concern to populations in which vitamin nutrition may already be suboptimal and has been the subject of recent brief reviews (02, R4, Tl, W13). 

In 1910, an autopsy study of 86 children with infantile beriberi concluded that 40% of these children had convulsions during their terminal illness. Nowadays, thiamine deficiency is very rare in developed countries. It may occur in breast-fed infants of thiamine deficient mothers. The onset of symptoms may be very abrupt and dramatic with high mortality rate. 

However, most cases of border line TDP deficit remain undiagnosed. Early symptoms of thiamine deficiency are frequently confused with other metabolic, cardiovascular, gastrointestinal or neurological conditions. Such underdiagnosed cases of thiamine deficiency are relatively frequent in developed countries, where an undernourished population is not thought to be a common problem. 

Wernicke s encephalopathy. This is most frequent clinical manifestation of thiamine deficiency in developed countries. It is frequently associated with alcoholism and other conditions impairing nutrition. This neuropsychiatric disorder is characterized by eye muscle paralysis, abnormal posture and gait, and impaired cognitive functions. Progressive deterioration of WE patients ends with KorsakofFs psychosis with manifestation of amnesia, stupor and loss of conceptual functions. 

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