World Stroke Day | analysis of the causes of hypoalbuminemia in ischemic stroke patients

*For medical professionals only

Albuminjun: "Today is the 17th World Stroke Day, and ischemic stroke is one of the leading causes of disability and death in Chinese mouth, accounting for about 70% of all stroke types in our country ^[1].

Hypoalbuminemia has been shown to be not only an independent risk factor for ischemic stroke, but also related to its severity and outcome ^[1-3].

The normal value of serum albumin in adults is 35~50 g/L, and < 30 g/L is hypoalbuminemia
.
Timely albumin supplementation in ischemic stroke patients with hypoalbuminemia has been shown to improve outcomes and reduce mortality ^[4].

So why do patients with ischemic stroke develop hypoalbuminemia? How should such patients supplement albumin in clinical practice? ”

Occurs in patients with ischaemic stroke

What causes hypoalbuminemia?

In clinical practice, many acute and chronic conditions can lead to hypoalbuminemia, such as cirrhosis, nephrotic syndrome, chronic digestive tract disease, tumors, extensive burns and trauma
.
Patients with ischemic stroke also often present with mild to moderate hypoalbuminemia, which is mostly associated with chronic inadequate intake, microalbuminuria, chronic inflammation, and acute post-stroke reactions ^[4].

Patients with the acute phase of ischemic stroke are often accompanied by decreased eating and increased consumption, which can lead to and exacerbate the occurrence and progression
of hypoalbuminemia.
According to statistics, the incidence of hypoalbuminemia is as high as 56% in patients with severe acute stroke who cannot eat ^[4-5].

Most strokes are associated with vascular lesions due to atherosclerosis, and microproteinuria is an early manifestation
of atherosclerosis.
Long-term microproteinuria can cause increased capillary permeability, increased inflammation and oxidative stress throughout the body, resulting in systemic hemodynamic changes and balance disorders, and ultimately leading to atherosclerotic vascular events
.
Thus, long-term microproteinuria is also a cause of hypoalbuminemia in patients with ischemic stroke ^[4,6].

As an important cause of ischemic stroke, atherosclerosis is actually a chronic inflammation, and chronic inflammation can reduce albumin concentration by reducing protein synthesis and promoting its metabolic breakdown, leading to and exacerbating the development of hypoalbuminemia ^[4,7-8].

Stroke can alter the patient's endocrine function, leading to increased stress release of adrenal glucocorticoids, which in turn protects the body from injury
by raising blood sugar and heart rate.
However, these reactions may exacerbate ischemic neuronal damage
.
Clinical studies have shown significantly lower
serum cortisol levels in patients with higher serum albumin levels.
Therefore, hypoalbuminemia in ischemic stroke patients is thought to be associated with high serum cortisol levels in the acute phase after stroke ^[4,9].

How should patients with ischemic stroke supplement albumin?

The 2018 guidelines for the diagnosis and treatment of acute ischemic cerebrovascular disease in China ^[1] pointed out that vomiting and dysphagia after stroke can cause dehydration and malnutrition, and the nutritional status of stroke patients is closely related to
the prognosis.
Post-stroke fluid and nutritional status assessment should be emphasized, with fluid and nutritional support
given as necessary.

Within 1~14 days after brain injury, cerebral edema can gradually occur and develop
.
Studies have shown that the early application of albumin for 14 days in the treatment of elderly patients with acute large-scale cerebral infarction can significantly improve the degree of neurological deficit and reduce the mortality rate, and also have a beneficial effect on their long-term prognosis, which is helpful for the recovery of patients ^[4,10].

In addition, because hypoalbuminemia is an independent risk factor for stroke [^2-4], the optimal time to correct hypoalbuminemia should not be limited to the acute phase, and timely correction of low albumin levels in people at high risk of cerebrovascular disease is also important for stroke prevention ^[4].

For patients with hypoalbuminemia, the idea that timely albumin supplementation can improve ischemic stroke outcomes and reduce mortality has been accepted
by most scholars.
However, there are not only timing and dosing issues
with albumin supplementation.
Currently, most studies have only shown that the acute phase of ischaemic stroke is associated with serum albumin levels, but clinically optimal albumin levels have not been established
.
Further large-scale clinical trials of high-dose albumin and how to use albumin safely and rationally also need to be explored ^[4].