Association between dairy intake, lipids and vascular structure and function in diabetes

Table 1 Baseline characteristics of the participants n (%)

Characteristic	Cohort (n = 108)
Age (yr)	58 ± 14
Weight (kg)	96.2 ± 20.6
BMI (kg/m2)	32.6 ± 6.4
Sex
Female	40 (37)
Male	68 (63)
Diabetes type
Type 1	14 (13)
Type 2	94 (87)
Time since diabetes diagnosis (yr)
Type 1	21 ± 13
Type 2	8 ± 7
Smoking status
Never smoked	56 (52)
Past smoker	47 (43)
Current smoker	5 (5)
Smoking pack years (years)a	10.5 ± 16.3
Prescribed anti-hypertensive medication	66 (61)
Prescribed lipid lowering medication	61 (57)
Diabetes treatment
None	22 (20)
OHA	49 (46)
Insulin	16 (15)
OHA + insulin	21 (19)
Presence of Microalbuminuria1	14 (13)
HbA1c	7.1 ± 1.2

All values are mean ± SD or n (%) where specified;

^aSmoking pack years = number packs (25 cigarettes)/day × number years smoked;

¹Albumin:creatinine > 2.5 for men and > 3.5 for women. BMI: Body mass index; OHA: Oral hypoglycaemic agents.

Table 2 Dietary intake measured using a food frequency questionnaire

Intake (g/d)	Cohort (n = 108)		P value for change
	Baseline	3 mo
Total dairy1	432 ± 218	434 ± 198	0.90
Total full fat dairy1	113 ± 201	94 ± 162	0.16
Milk	349 ± 201	345 ± 188	0.78
Yoghurt	55 ± 65	68 ± 76	0.031
Cheese	14 ± 12	11 ± 10	0.005
Butter	2 ± 6	1 ± 4	0.051
Ice-cream	11 ± 18	9 ± 10	0.063

¹Includes milk, yoghurt, cheese, butter, ice-cream. All values are mean ± SD; Data analysed using paired samples t-test.

Table 3 Spearman’s correlation of the change in total full fat dairy (milk, yoghurt, cheese, butter, ice-cream) with change in lipid species

Change in lipid species	rho value	P value
LPC 14:0	0.25	0.01
LPC 15:0	0.21	0.03
LPC 16:1	0.22	0.02
PC 29:0	0.22	0.02
PC 30:0	0.23	0.02
PC 31:0	0.19	0.049
CE 14:0	0.24	0.01

LPC: Lysophosphatidylcholine; PC: Phosphatidylcholine; CE: Cholesterol ester.

Table 4 Anthropometric measures, blood pressure, biochemistry and vascular measurements at baseline and follow-up

	Baseline	3 mo	P value for change
Weight (kg)	96.2 ± 20.6	95.9 ± 20.6	0.40
Peripheral systolic blood pressure (kPa)	16.9 ± 2.0	16.9 ± 1.9	0.75
Peripheral diastolic blood pressure (kPa)	9.4 ± 1.3	9.4 ± 1.3	0.69
Peripheral mean arterial pressure (kPa)	12 ± 1.3	12 ± 1.3	0.69
Peripheral pulse pressure (kPa)	7.4 ± 1.3	7.4 ± 1.7	0.93
Central systolic blood pressure (kPa)	16.8 ± 1.3	16.1 ± 1.9	0.004
Central diastolic blood pressure (kPa)	10.9 ± 1.3	10.5 ± 1.2	0.002
Central mean arterial pressure (kPa)	13.2 ± 1.5	12.8 ± 1.3	0.002
Central pulse pressure (kPa)	5.9 ± 1.7	5.8 ± 1.7	0.09
Central augmented pressure (kPa)	1.2 ± 0.6	1.1 ± 0.8	0.07
Augmentation index (%)	19 ± 7	21 ± 12	0.005
cfPWV (m/s)	9.4 ± 1.7	9.4 ± 1.8	0.63
Pulse transit time (m/s)	60 ± 10	60 ± 9	0.95
CCA-IMT (mm)	0.72 ± 0.12	0.71 ± 0.121	0.002
Total cholesterol (mmol/L)	3.7 ± 1.0	3.7 ± 1.0	0.59
HDL cholesterol (mmol/L)	1.2 ± 0.3	1.2 ± 0.3	0.54
LDL cholesterol (mmol/L)	2.0 ± 0.8	2.0 ± 0.7	0.40
Triglycerides (mmol/L)	1.1 ± 0.9	1.1 ± 0.9	0.53
Glucose (mmol/L)	7.3 ± 2.9	7.3 ± 2.7	0.95
High sensitivity C reactive protein (mg/L)	2.5 ± 2.4	2.4 ± 2.4	0.80

¹Follow-up was at 12 mo. All values are mean ± SD. Data analysed using paired samples t-test. cfPWV: Carotid femoral pulse wave velocity; CCA-IMT: Common carotid artery intima media thickness; HDL: High density lipoprotein; LDL: Low Density lipoprotein.

Table 5 Spearman’s correlation between the absolute and percent change in dairy associated lipid species and the absolute and percent change in vascular measures

	Absolute change		Percent change
	rho value	P value	rho value	P value
Central systolic blood pressure
LPC 14:0	0.30	0.007	0.28	0.01
PC 30:0	0.28	0.010	0.31	0.004
PC 31:0	0.20	0.07	0.22	0.046
Central diastolic blood pressure
LPC 14:0	0.32	0.004	0.32	0.00
LPC 15:0	0.23	0.04	0.22	0.046
LPC 16:1	0.23	0.035	0.21	0.06
PC 29:0	0.28	0.01	0.34	0.002
PC 30:0	0.36	0.001	0.40	0.001
PC 31:0	0.30	0.007	0.31	0.004
Central mean arterial pressure
LPC 14:0	0.30	0.007	0.29	0.009
PC 29:0	0.21	0.06	0.25	0.025
PC 30:0	0.31	0.005	0.33	0.002
PC 31:0	0.24	0.033	0.24	0.028
Augmentation index
Nil significant
cfPWV
Nil significant
CCA-IMT
CE 14:0	0.22	0.02	0.23	0.02

LPC: Lysophosphatidylcholine; PC: Phosphatidylcholine; CE: Cholesterol ester; cfPWV: Carotid femoral pulse wave velocity; CCA-IMT: Common carotid artery intima media thickness.