Objective       To investigate the changes and clinical value of endogenous plasma growth hormone secretagogue ghrelin in critically ill patients.       Methods       The levels of plasma active ghrelin

tumor necrosis factor-α (TNF-α) and interleukin 6 (IL-6) of 127 critically ill patients in ICU (patient group) and 30 healthy people (control group) were measured by enzyme-linked immunosorbent assay

and the subjects’ physiological indicators and laboratory examinations were rec

orded.       Results       (1) The level of plasma active ghrelin was significantly higher in the patient group than in the control group (

P

<

0.01). (2) According to the APACHE Ⅱ score

the patients were divided into a high-risk group (APACHE Ⅱ score≥15) and a low-risk group (APACHE Ⅱ score

<

15)

and the level of plasma active ghrelin was significantly higher in the high-risk group than in the low-risk group (

P

<

0.05). (3) In critically ill patients

the level of plasma active ghrelin was negatively correlated with body mass index (BMI) (

r

=-0.348

P

<

0.05)

and was positively correlated with TNF-α and IL-6 (

r

=0.375

P

<

0.05;

r

=0.562

P

<

0.01). Multiple linear regression analysis indicated that IL-6 was an independent related factor of plasma active ghrelin.       Conclusion       Plasma active ghrelin is highly expressed in critically ill patients

and may be related to malnutrition and inflammatory response in critical illness. The determination of plasma ghrelin level may contribute to the assessment of disease severity.