Statin use and cognitive function in middle-aged adults with type 1 diabetes

Table 2 Comparison of middle-aged adults with type 1 diabetes from the Pittsburgh Epidemiology of Diabetes Complications Study by duration of statin use

	Never used (n = 51)	1-6 yr (n = 25)	7-12 yr (n = 32)	P value1
Demographic and lifestyle factors, data are n (%), mean ± SD, or median (IQR)
Age at cognitive testing (yr)	47.5 ± 7.3	51.8 ± 6.1	51.0 ± 6.7	0.02
Female	27 (53%)	16 (64%)	12 (38%)	0.10
Years of education	15 ± 2	16 ± 3	14 ± 3	0.52
Ever smoking 100+ cigarettes5	22 (43%)	11 (44%)	8 (25%)	0.05
Apo E4 (24, 34, 44)	16 (31%)	7 (28%)	11 (34%)	0.66
BMI (kg/m2)	26.0 ± 4.3	27.6 ± 5.1	29.8 ± 4.7	0.002
Cognitive function
Cognitively impaired	7 (14%)	8 (32%)	15 (47%)	0.003
Estimated verbal IQ	108.6 ± 8.2	107.7 ± 10.0	106.5 ± 6.9	0.24
Memory domain z-score	0.24 ± 0.75	-0.23 ± 0.64	-0.25 ± 0.78	0.004
Executive function z-score	0.18 ± 0.56	-0.10 ± 0.82	-0.30 ± 0.79	0.06
Psychomotor speed z-score	0.29 ± 0.66	-0.33 ± 1.10	-0.28 ± 0.89	0.01
Visuo- construction z-score	0.21 ± 0.64	-0.16 ± 0.82	-0.21 ± 1.45	0.13
Type 1 diabetes-related factors
Diabetes duration (yr)	39.6 ± 5.8	43.4 ± 6.9	42.1 ± 6.5	0.03
Serum glucose (mg/dL)	188.6 ± 90.5	151.1 ± 73.6	173.0 ± 81.8	0.56
A1c > 7.5%, 14-yr average	27 (53%)	17 (68%)	25 (78%)	0.02
Glucose disposal rate (mg/kg per minutr)2	8.1 ± 2.0	7.5 ± 1.8	5.8 ± 2.9	< 0.001
Proliferative retinopathy2	17 (33%)	14 (58%)	20 (63%)	0.03
eGFR (mL/min per 1.73 m2)24	91.3 ± 21.1	79.7 ± 20.1	74.7 ± 27.5	0.02
Coronary artery disease2	5 (10%)	3 (12%)	10 (31%)	0.02
Cardiac autonomic neuropathy2	21 (47%)	14 (58%)	13 (46%)	0.36
Distal symmetric polyneuropathy2	22 (49%)	13 (57%)	17 (53%)	0.61
Cardio-metabolic factors
History of stroke5	1 (2%)	2 (8%)	2 (6%)	0.99
Systolic blood pressure (mmHg)	117.6 ± 12.0	119.6 ± 15.5	123.2 ± 19.3	0.44
Diastolic blood pressure (mmHg)	65.0 ± 9.5	64.6 ± 9.1	67.5 ± 10.6	0.18
History of high blood pressure3	13 (25%)	10 (40%)	16 (50%)	0.04
Study average LDLc (mg/dL)5	100.3 ± 25.6	112.2 ± 24.9	115.9 ± 24.7	0.02
Inflammatory markers
2WBC × 103/ mm2	5.9 (5.0-6.7)	6.2 (5.2-6.9)	6.2 (5.2-7.1)	0.29
Adiponectin (μg/mL)2	22.0 (15.7-30.7)	21.8 (14.2-31.4)	22.3 (15.2-28.3)	0.75
IL-6 (ng/mL)2	1.4 (0.7-1.9)	1.2 (0.8-1.7)	1.2 (1.0-1.6)	0.28
TNFα (pg/mL)2	1.3 (1.0-2.3)	1.2 (1.0-1.8)	1.3 (1.0-1.6)	0.07
C-reactive protein (mg/L)2	0.9 (0.6-2.3)	0.9 (0.2-1.6)	1.9 (0.6-4.1)	0.08

¹P values are adjusted for age and education;

²Assessed in 2004-2006;

³Defined as any EDC assessed SBP > 140 mmHg or DBP > 90, or ever self-reported use of anti-hypertensive medication from 1986-1988 through 2010-2013;

⁴Estimated per the Chronic Kidney Disease - Epidemiology (CKD-EPI) formula;

⁵Assessed from EDC baseline (1986-1988) through time of cognitive testing (2010-2013). Factors assessed at time of cognitive testing (2010-2013) unless otherwise specified. T1D: Type 1 diabetes; LDLc: Low density lipoprotein cholesterol; BMI: Body mass index; eGDR: Estimated glucose disposal rate; WBC: White blood cell count; IL-6: Interleukin-6; TNFα: Tumor necrosis factor alpha.