Evaluation of serum ferritin and some metal elements in type 2 diabetes mellitus patients: comparative cross-sectional study

Figures & data

Table 1 Clinical characterization of the diabetes and nondiabetes study subjects

Tested parameters	Study subjects		t-test	p-value
	Diabetes (n=214)	Nondiabetes (n=214)
Age (years)	43.18±12.68	43.18±12.68	−0.37	0.712
Duration with diabetes (years)	5.83±3.11	–	–	–
Fasting blood glucose (mg/dL)	162.16±29.53	78.56±10.73	38.92	<0.0001*
Body mass index (kg/m^2)	26.15±4.53	23.94±4.68	4.93	<0.0001*
Waist and hip circumference (cm)	1.43±0.56	1.04±0.37	8.52	<0.0001*
Systolic blood pressure (mmHg)	134.2±22.62	122.04±18.76	6.05	<0.0001*
Diastolic blood pressure (mmHg)	88.36±13.23	84.14±13.92	3.21	<0.0001*

Notes: Data were presented as mean (standard deviation).

* p<0.05 indicates a significant difference. Independent t-test.

Table 2 Levels of ferritin and metal elements in the serum of diabetes and nondiabetes study subjects

Tested parameters	Study subjects		t-test	p-value
	Diabetes (n=214)	Nondiabetes (n=214)
Zn^+2 (µg/dL)	46.26±21.03	72.41±21.47	−12.72	<0.0001*
Mg^+2 (mg/dL)	0.86±0.88	1.82±0.76	−11.95	<0.0001*
Cr^+3 (µg/L)	0.82±1.42	0.35±0.43	4.57	<0.0001*
Fe^+3 (µg/dL)	55.95±20.99	71.19±25.72	−6.70	<0.0001*
Ferritin (µg/L)	24.96±18.60	34.99±18.53	−5.58	<0.0001*
Cu^+2 (µg/dL)	79.61±27.38	71.67±22.38	3.28	<0.0001*
Mn^+2 (µg/L)	0.65±0.91	0.66±0.45	−0.18	0.853
Ca^+2 (mg/dL)	4.28±1.19	4.36±0.56	−0.83	0.407
Po4 ^−3 (mg/dL)	2.16±0.98	2.27±0.56	−1.40	0.162

Notes: Data were presented as mean (standard deviation).

* p<0.05 indicates a significant difference. Independent t-test.

Table 3 Clinical characteristics among oral hypoglycemic agent and injectable insulin users of diabetes study subjects

Tested parameters	Diabetes treatment options		t-test	p-value
	Oral hypoglycemic agents (n=161)	Injectable insulin (n=53)
Age (years)	42.57±13.4	44.11±9.9	−0.894	0.373
Fasting blood glucose (mg/dL)	159.88±27.4	169.07±34.5	−1.761	0.82
Body mass index (kg/m^2)	26.3±4.86	25.65±3.35	1.084	0.281
Waist and hip circumference (cm)	1.5±0.59	1.22±0.43	3.778	<0.0001*
Systolic blood pressure (mmHg)	134.3±24.1	133.9±17.5	0.105	0.928
Diastolic blood pressure (mmHg)	87.2±13.2	91.8±12.8	−2.255	0.025

Notes: Data were presented as mean (standard deviation).

* p<0.05 indicates a significant difference. Independent t-test.

Table 4 Levels of serum ferritin and metal elements among oral hypoglycemic agent and injectable insulin users of diabetes study subjects

Tested parameters	Diabetes treatment options		t-test	p-value
	Oral hypoglycemic agents (n=161)	Injectable insulin (n=53)
Zn^+2 (µg/dL)	45.8±20.84	47.6±21.76	−0.550	0.583
Mg^+2 (mg/dL)	0.85±0.89	0.89±0.89	−0.216	0.829
Cr^+3 (µg/L)	0.83±1.45	0.78±1.34	0.229	0.819
Fe^+3 (µg/dL)	57.79±20.49	50.37±21.71	2.252	<0.025*
Ferritin (µg/L)	26.72±19.70	19.62±13.58	2.439	<0.016*
Cu^+2 (µg/dL)	81.28±29.06	74.52±20.88	1.56	1.119
Mn^+2 (µg/L)	0.75±0.96	0.35±0.61	3.52	0.001*
Ca^+2 (mg/dL)	4.28±1.28	4.3±0.86	−0.156	0.877
Po4 ^−3 (mg/dL)	2.11±1.07	2.34±0.65	−1.88	0.062

Notes: Data were presented as mean (standard deviation).

* p<0.05 indicates a significant difference. Independent t-test.

Table 5 Pearson bivariate correlation analysis on serum ferritin and metal elements among diabetes study subjects

Tested parameters	Zn^+2 (µg/dL)	Mg^+2 (mg/dL)	Cr^+3 (µg/L)	Fe^+3 (µg/dL)	Ferritin (µg/L)	Cu^+2 (µg/dL)	Mn^+2 (µg/L)	Ca^+2 (mg/dL)	Po4 ^+3 (mg/dL)
Zn^+2 (µg/dL)
r	1	0.738	0.233	0.062	−0.032	−0.296	0.039	0.238	0.222
p-Value	–	<0.0001**	<0.001**	0.367	0.645	<0.0001**	0.572	<0.0001**	<0.001**
Mg^+2 (mg/dL)
r	0.738	1	0.358	−0.103	−0.042	−0.171	0.079	0.157	0.209
p-Value	<0.0001**	–	<0.0001**	0.134	0.544	0.012**	0.250	0.022	0.002**
Cr^+3 (µg/L)
r	0.233	0.358	1	0.01	0.031	−0.03	0.068	0.211	0.298
p-Value	<0.001**	<0.0001**	–	0.885	0.653	0.661	0.321	0.002*	<0.0001**
Fe^+3 (µg/dL)
r	0.062	−0.103	0.010	1	0.665	0.189	0.065	0.020	−0.058
p-Value	0.367	0.134	0.885	–	<0.0001**	0.0001**	0.343	0.772	0.402
Ferritin (µg/L)
r	−0.032	−0.042	0.031	0.665	1	0.327	0.085	0.024	0.006
p-Value	0.645	0.544	0.653	<0.0001**	–	<0.0001**	0.218	0.732	0.927
Cu^+2 (µg/dL)
r	−0.296	−0.171	−0.03	0.189	0.327	1	0.275	−0.138	−0.087
p-Value	<0.0001**	0.012**	0.661	<0.0001**	<0.0001**	–	<0.0001**	0.044	0.205
Mn^+2 (µg/L)
r	0.039	0.079	0.068	0.065	0.085	0.275	1	−0.144	−0.090
p-Value	0.572	0.250	0.321	0.343	0.218	<0.0001**	–	0.036	0.192
Ca^+2 (mg/dL)
r	0.238	0.157	0.211	0.020	0.024	−0.138	−0.144	1	0.527
p-Value	<0.0001**	0.022	0.002**	0.772	0.732	0.044	0.036	–	<0.0001**
Po4 ^+3 (mg/dL)
r	0.222	0.209	0.298	−0.058	0.006	−0.087	−0.090	0.527	1
p-Value	<0.001**	0.002**	<0.0001**	0.402	0.927	0.205	0.192	<0.0001**	–

Note:

** Pearson correlation is significant at the 0.01 level (two tailed).

Table 6 Pearson bivariate correlation analysis on serum ferritin and metal elements with body mass index, waist-to-hip ratio, and fasting blood glucose among diabetes study subjects

Tested parameters	Body mass index (kg/m^2)		Waist-to-hip ratio (cm)		Fasting blood glucose (mg/dL)
	r	p-value	r	p-value	r	p-value
Zn^+2 (µg/dL)	−0.331	<0.0001**	−0.340	<0.0001**	−0.186	0.006**
Mg^+2 (mg/dL)	−0.254	<0.0001**	−0.199	0.003*	−0.136	<0.0001**
Cr^+3 (µg/L)	−0.121	0.077	0.002	0.974	−0.023	0.734
Fe^+3 (µg/dL)	−0.099	0.148	−0.029	0.672	−0.111	0.106
Ferritin (µg/L)	−0.058	0.396	0.053	0.443	−0.100	0.144
Cu^+2 (µg/dL)	0.140	0.04	0.327	<0.0001**	0.057	0.404
Mn^+2 (µg/L)	0.021	0.755	0.282	<0.0001**	−0.008	0.912
Ca^+2 (mg/dL)	−0.335	<0.0001**	−0.372	<0.0001**	−0.141	0.040
Po4 ^−3 (mg/dL)	−0.380	<0.0001**	−0.309	<0.0001**	−0.159	<0.0001**

Notes: Data were presented as mean (standard deviation).

** Pearson correlation is significant at the 0.01 level (two tailed).