Sitagliptin: Is It Effective in Routine Clinical Practice?

Table 2

Parameter estimates using the Generalized Estimating Equations (GEE) model (imputed) ().

Parameter		Std. error	95% Wald confidence interval		Hypothesis test
			Lower	Upper	Wald chi-square	df	Sig.
(Intercept)	1.990	.5912	.831	3.149	11.326	1	.001
Years diagnosed
>20 years	.467	.2467	−.016	.951	3.590	1	.058
16–20 years	.319	.2447	−.161	.798	1.697	1	.193
11–15 years	.366	.2301	−.085	.817	2.528	1	.112
6–10 years	.292	.2186	−.137	.720	1.780	1	.182
1–5 years	0^a	—	—	—	—	—	—
Employment status
No	−.118	.1402	−.393	.157	.707	1	.401
Yes	0^a	—	—	—	—	—	—
Race
Indian	−.116	.1250	−.361	.129	.865	1	.352
Chinese	−.201	.1122	−.421	.019	3.218	1	.073
Malay	0^a	—	—	—	—	—	—
Marital status
Widower	.163	.3932	−.607	.934	.173	1	.678
Divorced	.274	.2920	−.299	.846	.878	1	.349
Married	.136	.2674	−.388	.660	.259	1	.611
Single	0^a	—	—	—	—	—	—
Gender
Female	.047	.985	−.147	.240	.223	1	.637
Male	0^a	—	—	—	—	—	—
Time of HbA1c level
7–12 months after sitagliptin	−.562	.0941	−.746	−.377	35.586	1	.000
3–6 months after sitagliptin	−.831	.0801	−.988	−.674	107.550	1	.000
Before initiation of sitagliptin (Baseline)	0^a	—	—	—	—	—	—
Number of antidiabetes	−.038	.1301	−.292	.217	.084	1	.773
Age	−.010	.0065	−.023	.003	2.345	1	.126
Changes in regimen
During initiation of sitagliptin	.101	.2169	−.324	.526	.216	1	.642
After initiation of sitagliptin	.020	.0981	−.172	.213	.043	1	.837
No change	0^a	—	—	—	—	—	—
Initiation dose of sitagliptin
100 mg	.057	.3022	−.536	.649	.035	1	.852
50 mg	.273	.2901	−.295	.842	.887	1	.346
25 mg	0^a
Medications prior to sitagliptin initiation
Others	.281	.2851	−.278	.840	.969	1	.325
Biguanide, sulphonylurea, and insulin	.384	.3392	−.281	1.049	1.281	1	.258
Sulphonylurea and insulin	.009	.3411	−.660	.678	.001	1	.979
Biguanide and insulin	.226	.3094	−.381	.832	.533	1	.465
Biguanide and sulphonylurea	.194	.1855	−.170	.558	1.092	1	.296
Insulin alone	.140	.4808	−.802	1.083	.085	1	.770
Sulphonylurea alone	.062	.1920	−.314	.438	.104	1	.747
Biguanide alone	0^a
Initiation of sitagliptin
Added to current regime	−.159	.1385	−.431	.112	1.318	1	.251
Switched from current regime	0^a
Baseline HbA1c	.790	.0407	.711	.870	377.159	1	000
(Scale)	1.114

Dependent variable: HbA_1c.
^aSet to zero because this parameter is redundant.