Downregulated level of insulin in COPD patients during AE; role beyond glucose control?

Figures & data

Table 1 Baseline characteristics of the patients and the controls

	AECOPD (n=22)	COPD (n=20)	Healthy (n=20)	P-value
Age	74.86±5.36	70.9±8.14	68.75±4.14	P>0.05
Men:women	18:4	15:5	16:4	P>0.05
Ever-smoker	16	16	15	P>0.05
BMI (kg/m^2)	20.88±2.54	20.83±2.16	21.29±1.23	P>0.05
FEV1(%)	43.23±11.22	49.02±15,7	88.15±5.28	P<0.05

Note: Data presented as mean±SD.

Abbreviations: AECOPD, acute exacerbationchronic obstructive pulmonary disease; BMI, body mass index; FEV1, forced expiratory volume in 1 second.

Figure 1 Serum glucose, insulin concentrations and HOMA-IR index in AECOPD patients, stable COPD patients and the health controls.

Notes: (A) comparison of glucose level; (B) comparison of insulin level; (C) comparison of HOMA-IR. Differences between subject groups were measured by ANOVA with post-hoc analysis performed using Tamhane’s test. (D) Comparison of HbA1C (%). *P-values <0.05.
Abbreviations: AECOPD, acute exacerbation of chronic obstructive pulmonary disease; HOMA-IR, homeostasis model assessment of insulin resistance; ANOVA, one-way analysis of variance.

Figure 2 Serum lipids levels of AECOPD patients, stable COPD patients and the health controls.

Notes: (A) comparison of TG level. (B) comparison of CHOL level. (C) comparison of LDL-CHOL level. (D) comparison of HDL-CHOL level. Differences between subject groups were measured by ANOVA with post-hoc analysis performed using Tamhane’s test. *P-values <0.05.
Abbreviations: TG, triglycerides; CHOL, total cholesterol; LDL-CHOL, low density lipoprotein cholesterol HDL-CHOL, high density lipoprotein cholesterol; AECOPD, acute exacerbation of chronic obstructive pulmonary disease; ANOVA, one-way analysis of variance.

Figure 3 Serum insulin and glucose levels during exacerbations and after recovery in AECOPD patients.

Notes: (A) Comparison of insulin level; (B) Comparison of glucose level; (C) Change of insulin level during exacerbations and after clinical recovery in 22 AECOPD patients; (D) Change of glucose level during exacerbations and after clinical recovery in 22 AECOPD patients. Differences between groups were measured by paired Student's t-test. *P-values <0.05.

Figure 4 Correlation of amplitude of insulin’s variation with amplitude of glucose’s variation during AE and after recovery.

Notes: Insulin’s variation: recovery-AE glucose’s variation: AE-recovery. Spearman correlation analysis was performed (r=−0.184, P=0.41).

Figure 5 Putative mechanism of insulin-IGF1-IGFBP7 network in AECOPD.

Notes: During AE: insulin and IGF1 flow from blood circulation to airway. IGFBP7 flows from airway to blood circulation. Recover from AE: insulin and IGF1 flow from airway to blood circulation. IGFBP7 flows from blood circulation to airway.
Abbreviations: AE, acute exacerbation; IGFBP7, insulin-like growth factor binding protein 7; IGF1, insulin-like growth factor 1; IR, insulin receptor; IGF1R, insulin-like growth factor 1 receptor.