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Three Possible Reasons for Fasting Plasma Glucose Test >7 mmol/L

Time: 2020-04-16 Hits: 1322

As the high fasting plasma glucose can not be treated just simply by increasing the dose of hypoglycemics. Before the reasons are found, the solutions may be completely different for same high level of fasting plasma glucose.

What is the fasting plasma glucose?

The fasting plasma glucose means the blood glucose level measured after the fasting for 8~12 hours (i.e. any food can not be taken, but water can be drunken).

Generally, blood glucose level is considered as too high when the fasting plasma glucose is more than 7 mmol/L.https://en.wikipedia.org/wiki/Blood_sugar_level

In order to know the treatment methods, the reasons for high fasting plasma glucose should first be found.

1. Excessive amount of supper at previous night.

This is the most common reason for high fasting plasma glucose, which is relevant to the amount and quality of supper and diet at night.

With an excessive intake but without exercise after the meal, less consumption occurs at night, so as to increase the amount of sugar released by food into blood. Of course, the high fasting plasma glucose may also be caused by the later supper.

In addition, the high fasting plasma glucose is also relevant to the rest state and sleep state at night. If poor sleep and sleepless state appear at night or if bad mood and great tiredness appear at night, the fasting plasma glucose will fluctuate in the morning, and is sometimes high or low.

If the high fasting plasma glucose occurs occasionally for several times, it doesn’t matter too much, and the hyperglycemia can be improved just through the diet controlling and stroll after meal. If the high fasting plasma glucose often occurs, the following two factors should be considered.

2. Diabetes mellitus dawn phenomenon: the blood glucose level is not low at night but rises in the morning

Blood glucose is not only adjusted by the energy released from food, but also regulated by various hormones, most of which can increase the blood glucose level (including glucocorticoid and growth hormone and ect.).

At dawn, these hormones begin to rise gradually, which act on the glycogen reserved in liver/muscle and are released into blood circulation; then the blood glucose level rises accordingly.

In medical science, the rise of blood glucose level at dawn is called as diabetes mellitus dawn phenomenon. Due to the influence of hyperglycemic hormones, the blood glucose level rises gradually. Therefore, the fasting plasma glucose may be higher than the predormital blood glucose at previous night.

How to monitor? When the blood glucose is very stable and hypoglycemia does not occur at night but the blood glucose rises gradually at dawn and the fasting plasma glucose peaks before the breakfast, a diabetes mellitus dawn phenomenon is considered.

How to treat? Based on the persistence in ordinary diet therapy, times of meal can be properly increased (i.e. 4~5 meals a day).

Meanwhile, one snacking should be increased at about one hour just before the sleep at night; a small amount of food containing carbohydrates and protein can be taken, such as one glass of milk, one bowl of congee or several pieces of bread. Through such methods, the secretion amount and sensitivity of insulin at night can be better improved.

Or, a doctor is directly seen to adjust the treatment regimen and increase the dose of hypoglycemics.

3. Somogyi effect: the blood glucose level is too low at night, but rises in the morning

When the hypoglycemia is prone to occur in the diabetes patients, the protective mechanism is initiated in their body, and the secretion of before-mentioned hyperglycemic hormones is increased, so as to increase the blood glucose level and cause a secondary hyperglycemia. This phenomenon is called as Somogyi effect.

To be worthy for alerting, in the diabetes patients with Somogyi effect, typical symptoms of hypoglycemia sometimes do not occur such as palpitation and cold sweating; meanwhile, since they are sleeping, the occurrence of hypoglycemic coma becomes very dangerous.

Hypoglycemia at midnight predicts a starting of nightmare.

How to monitor? In order to reduce the influence on sleep, the blood glucose is monitored at 2:00~3:00 a.m. When the conditions are allowable, 24h monitoring of blood glucose had better be performed in hospitals.

    If a hypoglycemia is indicated by measurement at 0:00~4:00 (i.e. ≤3.9 mmol/L), the rise of fasting plasma glucose before the breakfast is caused by Somogyi effect.

How to treat?

It is a premise for solving Somogyi effect to take a regular diet/exercise and take the hypoglycemics at proper dose.

For the diabetes patients receiving long-acting sulfonylureas drugs (such as Gliclazide Sustained-release Tablets and Glimepiride Tablets), premixed insulin and medium-acting or long-acting insulin, special attention should be paid to the influence of Somogyi effect.

The separation of meals is a good measure for preventing Somogyi effect.

In the diabetes patients with high postprandial blood glucose (>10 mmol/L) and low predormital blood glucose, 1/3 of supper can be taken at 21:30~22:00 p.m.

If the predormital blood glucose is <6.5 mmol/L, a snacking can be considered.

Noteworthily, if the diet is adjusted at night, the blood glucose must be monitored both after the supper and before the sleep.

At this moment, 4 pieces of soda biscuit or one glass of milk (225 ml) are properly added; too great worry must not be paid to whether a hyperglycemia occurs after the meal before the sleep; you should know that a greater harm will be produced after the occurrence of hypoglycemia.

Noteworthily, these methods are just temporary treatment means for diabetes mellitus dawn phenomenon or Somogyi effect.

In most cases, if the hypoglycemics needs to be adjusted, a doctor had better be seen in time for treatment. The most suitable treatment regimen will be selected by the doctors according to the actual conditions of illness.

Therefore, the high fasting plasma glucose is generally caused by four reasons:

1. Excessive intake of food at last night. Solutions: Take a less meal; or properly reduce the intake amount of foods rich in fat and protein.

2. Poor sleep at last night. Solutions: Go to bed in advance to enter the sleep mode; and do not browse mobile phone before sleep.

3. Diabetes mellitus dawn phenomenon. Solutions: Have more meals a day but less food at each meal; or increase the dose of hypoglycemics given before the sleep under the guidance of doctors.

4. Somogyi effect. Solutions: If the predormital blood glucose is <6.5 mmol/L, one glass of milk should be drunken, or some pieces of biscuit be taken.