Attenuated serum 25-hydroxyvitamin D and vitamin D binding protein associated with cognitive impairment in patients with type 2 diabetes

Figures & data

Figure 1 Flow diagram of patient flow in the study.

Table 1 Demographic data of cases and controls

Characteristic	Cases (n=44)	Control (n=44)
Age (years)	45.70±7.53	44.91±6.05
Sex
Female	21 (47.7)	18 (40.9)
Male	23 (52.3)	26 (59.1)
BMI (kg/m^2)	26.1±2.51	25.33±2.91
Education
Educated	33 (75)	38 (86.4)
Uneducated	11 (25)	6 (13.6)
Employment
Employed	26 (59.1)	30 (68.2)
Unemployed	18 (40.9)	14 (31.8)
Exercise (hours/day)	0.4±0.65	0.28±0.41
Diet
Vegetarian	9 (20.5)	6 (13.6)
Non-vegetarian	35 (79.5)	38 (86.4)
Sun exposure (hours/day)	0.97±1.65	0.57±0.759
FPG (mg/dL)	193.48±84.04	97.53±8.68**
Duration of diabetes (years)	5.42±5.36
HbA1c (%)	9.05±2.47
Diabetes treatment
Oral hypoglycemic	36 (81.81)
Insulin	8 (18.18)

Notes: **p<0.0001. Data presented as mean ± SD or n (%)

Abbreviations: n, number; BMI, body mass index; FPG, fasting plasma glucose; HbA1c, glycated hemoglobin.

Table 2 Association of variables among cases and controls

Variable	Cases (n=44)	Controls (n=44)	Crude OR	p-value	Adjusted OR*	p-value
Vitamin D deficiency	34 (77.3)	23 (52.3)	0.400 [0.144–1.112]	0.079	0.322 [0.128–0.809]	0.016
Vitamin D sufficiency	10 (22.7)	21 (47.7)	1		1
Cognitive impairment	17 (38.6)	7 (15.9)	5.810 [1.408–23.904]	0.015	4.405 [1.617–12.002]	0.004
No cognitive impairment	27 (61.4)	37 (84.1)	1		1
VDBP			1.003 [0.999–1.007]	0.350	1.003 [0.999–1.007]	0.051

Note: Data presented as n (%). *Adjusted for age, gender, employment status, education, HbA1c, sun-exposure, exercise, diet.

Abbreviations: n, number; VDBP, vitamin-D binding protein.

Table 3 Association of various parameters with MMSE scores

Parameter	Cognitive impairment (n=27)	No cognitive impairment (n=61)	Crude OR	p-value	Adjusted OR	p-value
Age	NA	NA	1.021 [0.925–1.126]	0.685	NA	NA
Male	12 (24.5)	37 (75.5)	1		NA	NA
Female	15 (38.5)	24 (31.5)	0.501 [0.017–14.350]	0.686
BMI	NA	NA	0.843 [0.619–1.150]	0.281	NA	NA
Educated	18 (25.4)	53 (74.6)	1		1
Uneducated	9 (52.9)	8 (47.1)	0.113 [0.015–0.832]	0.032	0.123 [0.023–0.667]	0.015
Employed	14 (25)	42 (75)	1		NA	NA
Unemployed	13 (40.6)	19 (59.4)	1.344 [0.455–3.968]	0.593
Exercise	NA	NA	1.201 [0.255–5.669]	0.817	NA	NA
Sun exposure	NA	NA	0.996 [0.566–1.752]	0.988	NA	NA
T2DM cases	17 (38.6)	27 (61.4)	3.625 [0.710–18.499]	0.121	1.008 [1.000–1.016]	0.044
Controls	7 (15.9)	37 (84.1)	1		1
Vitamin D deficiency	22 (91.7)	35 (54.7)	0.135[0.027–0.669]	0.014	0.131 [0.027–0.638]	0.014
Vitamin D sufficiency	2 (8.3)	29 (45.3)	1		1
VDBP	NA	NA	1.021 [0.925–1.126]	0.035	1.008 [1.001–1.015]	0.029

Note: Data presented as n (%).

Abbreviations: n, number; NA, not applicable; BMI, body mass index; T2DM, type 2 diabetes mellitus; VDBP, vitamin-D binding protein.

Figure 2 Prevalence of cognitive impairment in controls and cases.

Note: *p<0.05.

Figure 3 Generalised linear model of mini-mental state examination scores and vitamin D.