Night sweats, is it a problem with the kidneys?

Author: Chen Zhou Shanghai Changhai Hospital

Cartoon: Chen Zhou Shanghai Changhai Hospital

Reviewer: Mei Xiaobin, Chief Physician, Shanghai Changhai Hospital

Both Chinese and Western medicine have this view on "night sweats": they often occur at night when it is pitch dark. The word "steal" is used very cleverly, as if the sweat is being stolen. So, what exactly is night sweats? Is it a sign of kidney problems? If you want to understand "night sweats", you must first understand "sweating".

The meaning of sweating

The purpose of human sweating is mainly to lower body temperature, not to detoxify, because sweat is composed of water (about 99%) and a small amount of inorganic salts, urea, etc., and the toxins in the human body are mainly excreted by the kidneys in the form of urine, and some solid toxins are excreted in the form of feces. To be more serious, sweat glands have nothing to do with "detoxification" at all, and the main function of sweat glands is to dissipate heat.

Figure 1 Copyright image, no permission to reprint

Those who have studied physics may know that water has a relatively large specific heat, and the evaporation of sweat can take away a lot of heat, thereby helping the body to lower its body temperature. The human skin has about 2 million to 4 million sweat glands, which can discharge about 500 ml of water every day, which is equivalent to a bottle of Nongfu Spring. Of course, it seems a bit salty!

What are night sweats?

Night sweats are an abnormal sweating condition, also known as "sleep hyperhidrosis", which is a systemic hyperhidrosis that occurs during sleep. The symptoms can be mild or severe, ranging from a small amount of diffuse sweating to "sweating like rain" and the bed sheets need to be changed immediately after waking up. Of course, if the room is too hot or the quilt is too much, it does not belong to night sweats.

What are the causes of night sweats?

In fact, it is also very stressful for doctors to determine the cause of night sweats. In modern medicine, night sweats occur in many diseases and conditions.

•Tuberculosis : In addition to night sweats, people with active pulmonary tuberculosis may also experience cough, sputum production, fatigue, and weight loss.

• Malignant tumors : Some people with tumors experience night sweats, often accompanied by unexplained weight loss, fatigue, itchy skin, and enlarged lymph nodes.

•Infection : For example, typhoid and tick-borne diseases may be related to mosquito or tick bites or drinking unclean water. Night sweats may be the first manifestation. In addition, bacterial or viral infections (including new coronavirus infection and human immunodeficiency virus infection) can also cause night sweats.

•Hyperthyroidism : In addition to night sweats, patients with hyperthyroidism may also experience weight loss, increased heart rate, fear of cold, irritability, bulging eyes, and tremors.

• Neurological diseases : For example, patients with spinal cord injury and syringomyelia may experience paroxysmal systemic hyperhidrosis and night sweats.

• Sleep disorders : Night sweats are common in patients diagnosed with sleep disorders. One study evaluated night sweats in patients diagnosed with obstructive sleep apnea and found that approximately 33% of patients reported at least three night sweats per week.

• Adverse drug reactions : Drugs are common causes of increased sweating and night sweats, such as antidepressants and hypoglycemic drugs. If diabetic patients experience night sweats and dizziness, they should be careful about whether hypoglycemia has occurred.

•Abnormal hormone status : Women who are in menopause or use products containing estrogen may experience night sweats; male patients may also experience problems such as night sweats after receiving androgen deprivation therapy.

How to treat night sweats?

The cause of night sweats is relatively complex. Therefore, the treatment mainly focuses on finding the cause and then treating the primary disease. For example, for the obstructive sleep apnea patients mentioned above, the incidence of night sweats will decrease after continuous positive airway pressure treatment.

Professional issues in treatment should be left to professional doctors. It is important to note that you should not think of "kidney deficiency" when you mention night sweats, and think that everything will be fine if you take more tonic medicine. When a symptom appears, it reminds us to try our best to find the cause; when a disease is diagnosed, the treatment measures are relatively easy to deal with.