J Endocrinol Metab

Journal of Endocrinology and Metabolism, ISSN 1923-2861 print, 1923-287X online, Open Access

Article copyright, the authors; Journal compilation copyright, J Endocrinol Metab and Elmer Press Inc

Journal website https://jem.elmerpub.com

Original Article

Volume 15, Number 5, December 2025, pages 181-190

Prevalence of Diabetic Peripheral Neuropathy and Its Association With Vitamin B12 Deficiency and Health-Related Quality of Life

↓ **Table 1.** Sociodemographic Characteristics of the Participants (N = 367)^a
Variables	No. (%)	Neuropathy (N = 123)	No neuropathy (N = 244)	P value
^aStatistical significance was determined using the Chi-square test. *Statistically significant P-values (P values < 0.05).
Sex
Women	210 (57.2)	55 (44.7)	102 (41.8)	0.674
Men	157 (42.8)	68 (55.3)	142 (58.2)
Age (years)				0.003*
20 - 45	31 (8.4)	10 (8.1)	21 (8.6)
46 - 55	53 (14.4)	15 (12.2)	38 (15.6)
56 - 65	130 (35.4)	35 (28.5)	95 (38.9)
65 - 75	99 (27.0)	33 (26.8)	66 (27.0)
> 75	54 (14.7)	30 (24.4)	24 (9.8)
Marital status				0.39
Married	192 (52.3)	63 (51.2)	129 (52.9)
Divorced	21 (5.7)	10 (8.1)	11 (4.5)
Single	59 (16.1)	16 (13.0)	43 (17.6)
Common-law union	59 (16.1)	19 (15.4)	40 (16.4)
Widowed	36 (9.8)	15 (12.2)	21 (8.6)
Educational level				0.639
Postgraduate studies	48 (13.1)	16 (13.1)	32 (13.1)
None	1 (0.3)	0 (0)	1 (0.41)
None (can read)	6 (1.6)	4 (3.3)	2 (0.8)
Primary	63 (17.2)	25 (20.3)	38 (15.6)
Secondary	91 (24.8)	29 (23.6)	62 (25.4)
Technical	6 (1.6)	2 (1.6)	4 (1.6)
University	152 (41.4)	47 (38.2)	105 (43.0)
Smoker				0.785
Yes	18 (4.9)	5 (4.1)	13 (5.3)
No	349 (95)	118 (95.9)	231 (94.7)

↓ Table 1. Sociodemographic Characteristics of the Participants (N = 367)^a

Variables

No. (%)

Neuropathy (N = 123)

No neuropathy (N = 244)

P value

^aStatistical significance was determined using the Chi-square test. *Statistically significant P-values (P values < 0.05).

Sex

Women

210 (57.2)

55 (44.7)

102 (41.8)

0.674

Men

157 (42.8)

68 (55.3)

142 (58.2)

Age (years)

0.003*

20 - 45

31 (8.4)

10 (8.1)

21 (8.6)

46 - 55

53 (14.4)

15 (12.2)

38 (15.6)

56 - 65

130 (35.4)

35 (28.5)

95 (38.9)

65 - 75

99 (27.0)

33 (26.8)

66 (27.0)

> 75

54 (14.7)

30 (24.4)

24 (9.8)

Marital status

0.39

Married

192 (52.3)

63 (51.2)

129 (52.9)

Divorced

21 (5.7)

10 (8.1)

11 (4.5)

Single

59 (16.1)

16 (13.0)

43 (17.6)

Common-law union

59 (16.1)

19 (15.4)

40 (16.4)

Widowed

36 (9.8)

15 (12.2)

21 (8.6)

Educational level

0.639

Postgraduate studies

48 (13.1)

16 (13.1)

32 (13.1)

None

1 (0.3)

0 (0)

1 (0.41)

None (can read)

6 (1.6)

4 (3.3)

2 (0.8)

Primary

63 (17.2)

25 (20.3)

38 (15.6)

Secondary

91 (24.8)

29 (23.6)

62 (25.4)

Technical

6 (1.6)

2 (1.6)

4 (1.6)

University

152 (41.4)

47 (38.2)

105 (43.0)

Smoker

0.785

Yes

18 (4.9)

5 (4.1)

13 (5.3)

349 (95)

118 (95.9)

231 (94.7)

↓ **Table 2.** Clinical Characteristics of the Participants (N = 367)^a
Variables	Total (N = 367)	Neuropathy (N = 123)	No neuropathy (N = 244)	P-value
^aQuantitative variables are expressed as mean (standard deviation) or median (interquartile range), and qualitative variables as frequency (percentage). Statistical significance was determined using Student’s t-test, Mann-Whitney U, and Chi-square test. *Statistically significant P-values (P values < 0.05). BMI: body mass index; HDL: high-density lipoprotein; LDL: low-density lipoprotein; TSH: thyroid-stimulating hormone.
Time with diabetes (years)	12.0 (9.5)	14.8 (10.1)	10.6 (8.8)	< 0.001*
Treatment for diabetes
Oral antidiabetics	329 (89.6)	98 (79.7)	231 (94.7)	< 0.001*
Insulin	113 (30.8)	59 (48)	54 (22.1)	< 0.001*
Injectables	9 (2.5)	5 (4.1)	4 (1.6)	0.289
Diet and exercise	70 (19.1)	12 (9.8)	58 (23.8)	0.002*
Others	3 (0.8)	1 (0.8)	2 (0.8)	0.727
Metformin	282 (76.8)	85 (69.1)	197 (80.7)	0.018*
Comorbidities
Hypertension	284 (77.4)	101 (82.1)	183 (75.0)	0.16
Dyslipidemia	128 (34.9)	51 (41.5)	77 (31.6)	0.078
Chronic kidney disease	6 (1.6)	5 (4.1)	1 (0.4)	0.03*
Obesity	65 (17.7)	19 (15.4)	46 (18.9)	0.508
Cerebrovascular accident	12 (3.3)	8 (6.5)	4 (1.6)	0.035*
Acute myocardial infarction	7 (1.9)	5 (4.1)	2 (0.8)	0.081
Heart failure	3 (0.8)	2 (1.6)	1 (0.4)	0.543
Neuropathy	3 (0.8)	1 (0.8)	2 (0.8)	0.544
Retinopathy	8 (2.2)	6 (4.9)	2 (0.8)	0.033*
Others	138 (37.6)	42 (34.1)	96 (39.3)	0.045
Frequency of diabetes checkup visits (per year)	2.8 (1.5)	2.9 (1.7)	2.8 (1.4)	0.746
Frequency of foot evaluations (per year)	0.3 (1.2)	0.5 (1.9)	0.3 (0.6)	0.285
Metabolic parameters
Glycated hemoglobin	7.7 (1.91)	8.3 (2.1)	7.4 (1.8)	< 0.001*
Fasting glucose	142.6 (54.7)	158.4 (68.7)	133.4 (42.3)	0.003*
Total cholesterol	184.6 (47.8)	186.1 (48.1)	183.7 (47.7)	0.716
HDL cholesterol	48.3 (14.4)	47.0 (16.1)	48.9 (13.5)	0.105
LDL cholesterol	110.0 (41.6)	111.0 (40.8)	109.2 (42.1)	0.791
Triglycerides	141.4 (83.2)	149.2 (69.6)	137.2 (89.7)	0.101
Creatinine	1.0 (0.5)	1.1 (0.6)	0.89 (0.31)	0.034*
Vitamin B12	527.6 (318.4)	575.6 (355.7)	503.4 (295.6)	0.035*
TSH	2.4 (1.7)	2.3 (1.4)	2.5 (1.78)	0.615
Folic acid	18.0 (5.7)	17.6 (4.9)	18.5 (6.3)	0.749
Hemoglobin	13.4 (1.4)	13.1 (1.3)	13.5 (1.5)	0.011*
BMI	29.5 (5.2)	29.1 (5.0)	29.6 (5.4)	0.468
Systolic blood pressure	130 (25)	135 (30)	130 (20)	0.027*
Diastolic blood pressure	80 (10)	80 (10)	80 (15)	0.392

↓ Table 2. Clinical Characteristics of the Participants (N = 367)^a

Variables

Total (N = 367)

Neuropathy (N = 123)

No neuropathy (N = 244)

P-value

^aQuantitative variables are expressed as mean (standard deviation) or median (interquartile range), and qualitative variables as frequency (percentage). Statistical significance was determined using Student’s t-test, Mann-Whitney U, and Chi-square test. *Statistically significant P-values (P values < 0.05). BMI: body mass index; HDL: high-density lipoprotein; LDL: low-density lipoprotein; TSH: thyroid-stimulating hormone.

Time with diabetes (years)

12.0 (9.5)

14.8 (10.1)

10.6 (8.8)

< 0.001*

Treatment for diabetes

Oral antidiabetics

329 (89.6)

98 (79.7)

231 (94.7)

< 0.001*

Insulin

113 (30.8)

59 (48)

54 (22.1)

< 0.001*

Injectables

9 (2.5)

5 (4.1)

4 (1.6)

0.289

Diet and exercise

70 (19.1)

12 (9.8)

58 (23.8)

0.002*

Others

3 (0.8)

1 (0.8)

2 (0.8)

0.727

Metformin

282 (76.8)

85 (69.1)

197 (80.7)

0.018*

Comorbidities

Hypertension

284 (77.4)

101 (82.1)

183 (75.0)

0.16

Dyslipidemia

128 (34.9)

51 (41.5)

77 (31.6)

0.078

Chronic kidney disease

6 (1.6)

5 (4.1)

1 (0.4)

0.03*

Obesity

65 (17.7)

19 (15.4)

46 (18.9)

0.508

Cerebrovascular accident

12 (3.3)

8 (6.5)

4 (1.6)

0.035*

Acute myocardial infarction

7 (1.9)

5 (4.1)

2 (0.8)

0.081

Heart failure

3 (0.8)

2 (1.6)

1 (0.4)

0.543

Neuropathy

3 (0.8)

1 (0.8)

2 (0.8)

0.544

Retinopathy

8 (2.2)

6 (4.9)

2 (0.8)

0.033*

Others

138 (37.6)

42 (34.1)

96 (39.3)

0.045

Frequency of diabetes checkup visits (per year)

2.8 (1.5)

2.9 (1.7)

2.8 (1.4)

0.746

Frequency of foot evaluations (per year)

0.3 (1.2)

0.5 (1.9)

0.3 (0.6)

0.285

Metabolic parameters

Glycated hemoglobin

7.7 (1.91)

8.3 (2.1)

7.4 (1.8)

< 0.001*

Fasting glucose

142.6 (54.7)

158.4 (68.7)

133.4 (42.3)

0.003*

Total cholesterol

184.6 (47.8)

186.1 (48.1)

183.7 (47.7)

0.716

HDL cholesterol

48.3 (14.4)

47.0 (16.1)

48.9 (13.5)

0.105

LDL cholesterol

110.0 (41.6)

111.0 (40.8)

109.2 (42.1)

0.791

Triglycerides

141.4 (83.2)

149.2 (69.6)

137.2 (89.7)

0.101

Creatinine

1.0 (0.5)

1.1 (0.6)

0.89 (0.31)

0.034*

Vitamin B12

527.6 (318.4)

575.6 (355.7)

503.4 (295.6)

0.035*

TSH

2.4 (1.7)

2.3 (1.4)

2.5 (1.78)

0.615

Folic acid

18.0 (5.7)

17.6 (4.9)

18.5 (6.3)

0.749

Hemoglobin

13.4 (1.4)

13.1 (1.3)

13.5 (1.5)

0.011*

BMI

29.5 (5.2)

29.1 (5.0)

29.6 (5.4)

0.468

Systolic blood pressure

130 (25)

135 (30)

130 (20)

0.027*

Diastolic blood pressure

80 (10)

80 (15)

0.392

↓ **Table 3.** Logistic Regression Model for the Presence of Diabetic Peripheral Neuropathy
	OR (95% CI)	P-value
*Statistically significant P-values (P values < 0.05). CI: confidence interval; OR: odds ratio.
Dependent variable
Diabetic peripheral neuropathy
Independent variables
Sex	1.14 (0.71, 1.81)	0.587
Age	1.03 (1.01, 1.05)	0.009*
Vitamin B12 deficiency	0.31 (0.07, 1.42)	0.131
Metformin	0.73 (0.43, 1.25)	0.248
Chronic kidney disease	10.4 (1.14, 95.03)	0.038*
Diabetic retinopathy	5.05 (0.96, 26.54)	0.056
Dyslipidemia	1.59 (0.99, 2.56)	0.057
Stroke	3.55 (1.02, 12.39)	0.047*

↓ Table 3. Logistic Regression Model for the Presence of Diabetic Peripheral Neuropathy

OR (95% CI)

P-value

*Statistically significant P-values (P values < 0.05). CI: confidence interval; OR: odds ratio.

Dependent variable

Diabetic peripheral neuropathy

Independent variables

Sex

1.14 (0.71, 1.81)

0.587

Age

1.03 (1.01, 1.05)

0.009*

Vitamin B12 deficiency

0.31 (0.07, 1.42)

0.131

Metformin

0.73 (0.43, 1.25)

0.248

Chronic kidney disease

10.4 (1.14, 95.03)

0.038*

Diabetic retinopathy

5.05 (0.96, 26.54)

0.056

Dyslipidemia

1.59 (0.99, 2.56)

0.057

Stroke

3.55 (1.02, 12.39)

0.047*

↓ **Table 4.** SF-36 Scores by Dimension (N = 367)^a
Variables	Total (N = 367)	Neuropathy (N = 123)	No neuropathy (N = 244)	P-value
^aStatistical significance was determined using Student’s t-test and the Mann-Whitney U test. *Statistically significant P-values (P values < 0.05). MCS: Mental Component Summary; PCS: Physical Component Summary; SF-36: 36-Item Short Form Health Survey.
PCS	48.6 (8.8)	44.3 (8.9)	50.8 (7.9)	< 0.001*
Physical functioning	78.5 (23.2)	69.3 (25.8)	83.2 (20.4)	< 0.001*
Physical role limitations	71.2 (29.7)	60.4 (32.0)	76.8 (26.9)	< 0.001*
Bodily pain	65.2 (27.3)	56.1 (28.0)	70.0 (25.8)	< 0.001*
General health	64.1 (22.2)	58.2 (25.0)	67.1 (20.1)	0.002*
MCS	50.5 (10.2)	50.0 (10.8)	50.7 (10.0)	0.566
Mental health	73.8 (19.6)	71.6 (21.1)	74.9 (18.7)	0.208
Social functioning	81.0 (23.0)	76.4 (25.8)	83.3 (21.1)	0.19
Vitality	66.5 (20.5)	61.8 (22.4)	69.0 (19.1)	0.003*
Emotional role limitations	77.3 (26.3)	74.5 (26.5)	78.9 (26.1)	0.118

↓ Table 4. SF-36 Scores by Dimension (N = 367)^a

Variables

Total (N = 367)

Neuropathy (N = 123)

No neuropathy (N = 244)

P-value

^aStatistical significance was determined using Student’s t-test and the Mann-Whitney U test. *Statistically significant P-values (P values < 0.05). MCS: Mental Component Summary; PCS: Physical Component Summary; SF-36: 36-Item Short Form Health Survey.

PCS

48.6 (8.8)

44.3 (8.9)

50.8 (7.9)

< 0.001*

Physical functioning

78.5 (23.2)

69.3 (25.8)

83.2 (20.4)

< 0.001*

Physical role limitations

71.2 (29.7)

60.4 (32.0)

76.8 (26.9)

< 0.001*

Bodily pain

65.2 (27.3)

56.1 (28.0)

70.0 (25.8)

< 0.001*

General health

64.1 (22.2)

58.2 (25.0)

67.1 (20.1)

0.002*

MCS

50.5 (10.2)

50.0 (10.8)

50.7 (10.0)

0.566

Mental health

73.8 (19.6)

71.6 (21.1)

74.9 (18.7)

0.208

Social functioning

81.0 (23.0)

76.4 (25.8)

83.3 (21.1)

0.19

Vitality

66.5 (20.5)

61.8 (22.4)

69.0 (19.1)

0.003*

Emotional role limitations

77.3 (26.3)

74.5 (26.5)

78.9 (26.1)

0.118

↓ Table 5. Multiple Linear Regression Models for the Composite Quality of Life Scores of the SF-36

Method

Adjusted R²

β (95% CI)

P-value

^aBeing single was used as the reference category for marital status. *Statistically significant P-values (P values < 0.05). CI: confidence interval; MCS: Mental Component Summary; OLS: ordinary least squares; PCS: Physical Component Summary; SF-36: 36-Item Short Form Health Survey.

Model I

OLS

0.24

19.68

Dependent variable

PCS

Independent variables

Sex (male)

3.6 (1.9, 5.2)

< 0.001*

Age

-0.1 (-0.2, -0.06)

< 0.001*

Educational level

0.6 (-0.02, 1.2)

0.059

Degree of hypertension

-0.6 (-1.2, 0.1)

0.072

Number of comorbidities

-1.3 (-2.1, -0.4)

0.004*

Diabetic peripheral neuropathy

-5.5 (-7.3, -3.8)

< 0.001*

Model II^a

OLS

0.1

5.42

Dependent variable

MCS

Independent variables

Sex (male)

4.1 (1.9, 6.3)

< 0.001*

Age

0.2 (0.1, 0.3)

< 0.001*

Married

0.3 (-2.7, 3.2)

0.852

Divorced

2.7 (-2.2, 7.7)

0.278

Common-law union

1.3 (-2.4, 4.9)

0.493

Widowed

-6.7 (-10.9, -2.5)

0.002*

Educational level

-0.3 (-1.1, 0.4)

0.407

Number of comorbidities

0.2 (-0.9, 1.3)

0.755

Diabetic peripheral neuropathy

-1.6 (-3.8, 0.6)

0.161