Evaluation of ghrelin level and appetite regulation in patients with acute exacerbations of chronic obstructive pulmonary disease

Figures & data

Table 1 Patient characteristics

	Controls (n=23)	AECOPD (n=36)
Age, years	66.9±6.7	65.6±7.6a
Sex, male/female	15/8	27/9
Body mass index, kg/m^2	22.39±3.51	20.5±2.98†
Smoking history
Nonsmokers, n	7	14
Smokers, n (pack years)	16 (30.5±26.8)	22 (39.03±30.4)a
Pulmonary function
FEV1, L	1.59±0.84a	0.86±0.40*,a
FEV1, %Ref	91.79±12.53	35.39±13.64*,a
FEV1/FVC, %	75.62±3.81	40.04±8.31*
FVC, L	2.92±0.65	2.11±0.71*
FVC, %Ref	91.85±12.24	67.41±20.92*
Length of remission, days		11.7±3.52
Duration of disease, years		14.2±6.78
Severity stage, n
I		NA
II		4
III		16
IV		16
Medication use, n
Antibiotics		36
Intravenous glucocorticoids		12
Inhaled glucocorticoids and β-agonist		34
Anticholinergics		14
With pulmonary heart disease, n		17

Notes:

a Data with skewed distribution were expressed as medians [IQR]

* P<0.001

† P=0.021.

Abbreviations: AECOPD, acute exacerbation of chronic obstructive pulmonary disease; FVC, forced vital capacity; FEV₁, forced expiratory volume in one second; IQR, interquartile range; Ref, reference value; NA, not applicable.

Table 2 Results of blood analysis and biochemical indices

	Controls (n=23)	AECOPD
		Admission (n=36)	Discharge (n=23)
Blood gas analysis
pO2, mmHg	79.9±6.2	74.5±19.3	75.45±11.0
pCO2, mmHg	39.1±1.4	55.2±9.8*,a	48.8±7.3
pH	7.39±0.02	7.39±0.05	7.40±0.03
HCO3, mmol/L	24.5±1.2	32.4±4.3*	30.5±4.1
Biochemistry
Protein, g/L	72.1±3.37a	64.4±8.08*,a	60.3±6.58
Albumin, g/L	45.6±3.37	37.6±3.95*	35.3±4.47
Cholesterol, mmol/L	4.0±0.34	4.0±0.76	3.8±0.81
Glucose, mmol/L	5.2±0.50	5.6±0.86†	5.6±0.80
Potassium, mmol/L	4.1±0.18	4.08±0.41	4.0±0.43
Sodium, mmol/L	138.3±1.81	141.6±4.76*	142.1±5.5
Routine analysis of blood
Hemoglobin, g/L	139.8±12.2	129.6±14.3‡	130.6±16.3
WBC ×10^9/L	6.03±1.41	8.23±3.31*,a	7.56±2.14
Neutrophils, %	50.7±17.0a	76.5±9.52*	72.0±6.41
Inflammatory markers
CRP, mg/L	6.0±2.71	33.5±9.54*,a	22.4±17.3a
IL-6, pg/mL	5.4±2.73	14.6±7.2*,a	14.8±9.6a

Notes:

a Data with skewed distribution were expressed as medians [IQR].

* P<0.001

† P=0.023

‡ P=0.00 for AECOPD versus controls.

Abbreviations: AECOPD, acute exacerbation of chronic obstructive pulmonary disease; CRP, C-reactive protein; WBC, white blood cells; IL-6, interleukin 6; pO₂, pressure of oxygen; pCO₂, pressure of carbon dioxide.

Figure 1 Caloric intake and SNAQ score in patients with AECOPD and healthy controls.

Notes: The SNAQ score was significantly lower in patients with AECOPD than in healthy controls (P<0.001). Patients with AECOPD had a lower calorie intake in 1 day than healthy controls (P<0.001, 95% confidence interval −721.8, −499.3).

Abbreviations: AECOPD, acute exacerbation of chronic obstructive pulmonary disease; SNAQ, Simplified Nutritional Appetite Questionnaire.

Figure 2 Caloric intake and SNAQ score in patients with AECOPD at admission and on discharge.

Notes: Patients with AECOPD at admission had significantly lower SNAQ scores (P<0.001, 95% confidence interval −4.2, −2.8) and had a lower calorie intake (P<0.001, 95% confidence interval −429.8, −306.1) than when evaluated at discharge.
Abbreviations: AECOPD, acute exacerbation of chronic obstructive pulmonary disease; SNAQ, Simplified Nutritional Appetite Questionnaire.

Figure 3 Acyl ghrelin, total ghrelin, obestatin, and acyl to total ghrelin ratios in patients with AECOPD and healthy controls.

Notes: The circulating level of acyl ghrelin was not significantly different between patients with AECOPD and healthy controls (66.81±42.88 pg/mL versus 81.30±33.31 pg/mL, P=0.327, 95% confidence interval −30.7, 10.4). In addition, there was no significant difference in levels of total ghrelin (623.61±196.24 pg/mL versus 556.83±186.21 pg/mL, P=0.199, 95% confidence interval −36.1, 169.6) or obestatin (402.04±139.94 pg/mL versus 384.88±133.04 pg/mL, P=0.478). The acyl to total ghrelin ratio was significantly lower in patients with AECOPD than in healthy controls (P=0.003).
Abbreviation: AECOPD, acute exacerbation of chronic obstructive pulmonary disease.

Figure 4 Acyl ghrelin, total ghrelin, obestatin, and acyl to total ghrelin ratio in patients with AECOPD at admission and on discharge.

Notes: Patients with AECOPD had a significantly higher circulating level of total ghrelin at admission than on discharge (627.20±234.86 pg/mL versus 500.82±181.01 pg/mL, P=0.001, 95% CI 59.3, 193.4). The obestatin level was higher at admission than on discharge (410.05±152.35 pg/mL versus 354.94±127.80 pg/mL, P=0.063, 95% CI −3.2, 113.4). In addition, there were no significant differences in the acyl ghrelin level (67.77±50.29 pg/mL versus 71.24±70.05 pg/mL, P=0.778, 95% CI −21.8, 28.7) or acyl to total ghrelin ratio (P=0.290, 95% CI −0.03, 0.30).
Abbreviations: AECOPD, acute exacerbation of chronic obstructive pulmonary disease; CI, confidence interval.

Figure 5 Difference in albumin level in patients with AECOPD at admission and on discharge versus total ghrelin level.

Note: The difference in albumin level in patients with an AECOPD at discharge and on admission was positively correlated with total ghrelin level (r=0.457, P=0.028).
Abbreviation: AECOPD, acute exacerbation of chronic obstructive pulmonary disease.