Islet β-cell function preservation by different anti-diabetic treatments in Chinese elderly patients with type 2 diabetes mellitus

Table 5 Comparisons of β-cell response, insulin sensitivity and insulin resistance before and after different anti-diabetic treatments

	Insulin	OAD	Insulin + OAD	P value
C peptide index [ΔC30/ΔG30]
Before	0.095 (0.025-0.14)	0.103 (0.04-0.17)	0.076 (0-0.07)	0.235
After	0.125 (0.03-0.182)	0.1 (0.03-0.27)	0.067 (0.02-0.12)	< 0.001
Log HOMA-β
Before	5.92 ± 0.17	5.91 ± 0.08	5.49 ± 0.08	< 0.001
After	5.47 ± 0.11	5.73 ± 0.08	5.32 ± 0.08	< 0.001
Log HOMA-IR
Before	2.63 ± 0.13	2.68 ± 0.08	2.76 ± 0.07	0.933
After	2.89 ± 0.15	2.79 ± 0.09	2.886 ± 0.08	0.175
Matsuda index (ISI)
Before	17.89 ± 7.6	13.4 ± 3	16.24 ± 4	< 0.001
After	14.43 ± 6.1	11.9 ± 2.8	14.1 ± 11.3	< 0.001

Data were presented as mean ± SD or median with interquartile range. The value of HOMA-β and HOMA-IR were expressed by mean ± SD after log transformation. P value was derived from the One-Way ANOVA or Kruskal-Waillis test among the three groups. OAD: Oral anti-diabetes drugs; AUC: Area under the curve; HOMA-β: Homeostasis Model for β-cell function; HOMA-IR: Homeostasis Model for Insulin Resistance; ISI: Insulin sensitivity index.