Certain sulfonylurea drugs increase serum free fatty acid in diabetic patients: A systematic review and meta-analysis

Table 1 Demographic characteristics of the enrolled studies

	Ref.	Publication yr	Country	Ethnicity	Disease	Duration time	Intervention	N	FFA in mmol/L	SD	Age	Sex, M/F	BMI
1	Hasegawa et al[24]	2008	Japan	Asian	T2DM	12 wk	Control	11	0.50	0.19	56.1 ± 6.6	5/6	23.5 ± 3.3
							Glimepiride	13	0.48	0.20	55.6 ± 7.0	6/7	23.5 ± 3.3
2	Ebeling et al[25]	2001	Finland	Caucasian	T2DM	24 wk	Control	10	0.72	0.07	55.2 ± 1.8	NM	31.9 ± 1.5
							Glibenclamide	10	0.73	0.06	55.2 ± 1.8	NM	30.2 ± 1.7
3	Hanefeld et al[26]	2007	Germany	Caucasian	T2DM	52 wk	Control	195	0.70	0.30	60.4 ± 8.2	133/62	28.7 ± 3.7
							Glibenclamide	203	0.80	0.30	60.1 ± 8.3	143/60	28.7 ± 3.9
4	Li et al[27]	2010	China	Asian	T2DM	4 wk	Control	20	0.43	0.18	52.05 ± 8.06	9/11	24.91 ± 2.99
							Glimepiride	16	0.61	0.44	51.93 ± 11.07	9/7	25.76 ± 3.37
							Gliclazide	16	0.39	0.16	50.06 ± 8.68	7/9	25.17 ± 3.24
5	Pfützner et al[28]	2005	Germany	Caucasian	T2DM	26 wk	Control	89	0.50	0.20	62.2 ± 8.4	55/34	31.7 ± 5.0
							Glimepiride	84	0.56	0.19	63.0 ± 7.4	52/32	31.8 ± 4.3
6	Tang et al[29]	2004	China	Asian	T2DM	24 wk	Control	29	0.60	0.20	53.8 ± 9.7	18/11	24.6 ± 2.2
							Glimepiride	33	0.70	0.20	56.4 ± 8.8	21/12	23.3 ± 1.7
							Glimepiride + metformin	32	0.60	0.20	56.8 ± 7.3	17/15	24.0 ± 2.8
7	Hamann et al[30]	2008	Germany	Caucasian	T2DM	52 wk	Control	294	0.45	0.20	58.5 ± 9.6	155/139	33.0 ± 5.9
							Glienclamide + metformin	301	0.58	0.27	59.3 ± 9.2	158/143	32.2 ± 4.9
8	Yu et al[31]	2003	China	Asian	T2DM	12 wk	Control	48	0.52	0.19	54.9 ± 8.1	NM	25.9 ± 3.0
							Glimepiride + pioglitazone	56	0.57	0.21	55.9 ± 8.5	NM	25.5 ± 3.5
9	Riccio et al[32]	1996	Italy	Caucasian	NIDDM	4 wk	Control	17	0.26	0.06	52 ± 5	8/9	27.7 ± 0.5
							Gliclazide	17	0.23	0.04	52 ± 5	8/9	27.7 ± 0.5
10	Shen et al[33]	1991	China	Asian	NIDDM	16 wk	Control	6	0.11	0.63	60 ± 2	NM	26.1 ± 0.92
							Glibenclamide	6	0.47	0.06	58 ± 5	NM	27.6 ± 1.35
11	Chou et al[34]	2008	United States	Caucasian	T2DM	28 wk	Control	230	0.40	0.21	53.6 ± 10.7	138/92	31.3 ± 5.8
							Glimepiride	222	0.47	0.22	53.0 ± 11	128/94	31.8 ± 7.2
							Glimepiride ± rosiglitazone	224	0.41	0.20	54.5 ± 10.6	132/92	31.8 ± 6.4
12	Skrapari et al[35]	2001	Greece	Caucasian	T2DM	2 wk	Control	8	0.80	0.30	54 ± 11	NM	26.9 ± 0.6
							Glibenclamide	8	1.0	0.7	54 ± 11	NM	26.9 ± 0.6
13	Yamanouchi et al[36]	2005	Japan	Asian	T2DM	48 wk	Control	38	0.24	0.14	55.2 ± 9.2	18/20	25.8 ± 4.2
							Glimepiride	37	0.48	0.20	55.6 ± 9.3	19/18	25.6 ± 3.5

FFA: Free fatty acid; M/F: Male/female; BMI: Body mass index; T2DM: Type 2 diabetes mellitus; NIDDM: Non-insulin dependent diabetes mellitus; NM: Not mentioned; SD: Standard deviation.

Table 2 Summaries of overall and subgroup analysis

Subtype	Categories	RCTs	No. of patients	MD	95%CI	I2 (%)	P value
Total effect analysis		13	2273	0.08	0.03-0.12	76	< 0.01
Combination drug therapy		4	613	0.14	0.01-0.28	96	< 0.01
Duration time (interaction P < 0.01)	≥ 12 wk	10	2171	0.09	0.04-0.13	71	< 0.01
	< 12 wk	3	102	0.01	-0.07-0.09	9	0.33
Ethnicity (interaction P = 0.59)	Asian	6	361	0.10	-0.01-0.20	74	< 0.01
	Caucasian	7	1912	0.06	0.02-0.11	78	< 0.01
Different SU (interaction P = 0.72)	Glimepiride	6	941	0.10	0.02-0.19	78	< 0.01
	Glibenclamide	4	528	0.08	0.01-0.15	39	0.18
Age (interaction P = 0.34)	≥ 55	8	1395	0.09	0.04-0.14	65	< 0.01
	< 55	5	878	0.05	-0.02-0.11	65	0.02
BMI (interaction P = 0.57)	≥ 28	5	1895	0.07	0.03-0.11	96.2	0.03
	< 28	8	379	0.10	-0.01-0.21	88.1	< 0.01

SU: Sulfonylurea; BMI: Body mass index; MD: Mean difference; CI: Confidence interval; RCT: Randomized controlled trial.