Altered hippocampal subfield volumes are associated with memory and executive function in patients with type 2 diabetes mellitus

Table 1 Demographic, clinical, and neuropsychological characteristics of the participants

	T2DM (n = 55)	HC (n = 30)	t/χ2	P value
Age (years)	51.07 ± 10.45	45.76 ± 11.44	2.144	0.035a
Duration (months)	57.31 ± 64.56	-	-	-
Sex (male)	45 (81.8)	179 (70.8)	0.837	0.360
Education (years)	13.07 ± 3.41	12.86 ± 4.14	0.147	0.884
BMI (kg/m2)	25.36 ± 2.87	24.87 ± 3.90	0.488	0.627
MMSE	27.69 ± 1.57	27.55 ± 1.29	0.287	0.775
MoCA	25.18 ± 2.95	26.27 ± 3.90	-1.059	0.294
HAMD	6.55 ± 5.29	4.82 ± 7.32	0.925	0.359
HAMA	7.51 ± 5.68	6.27 ± 8.13	0.611	0.543
DST	13.78 ± 5.11	18.73 ± 5.90	-2.859	0.006a
Memory scale	10.32 ± 3.51	9.96 ± 5.64	0.279	0.781
TMT-A	50.57 ± 25.16	38.01 ± 19.23	1.564	0.123
TMT-B	93.27 ± 63.19	66.70 ± 42.44	1.332	0.188
SDMT	41.11 ± 14.10	51.55 ± 17.05	-2.164	0.034a
AVLT-N1	4.17 ± 1.96	4.18 ± 2.48	-0.022	0.982
AVLT-N2	7.06 ± 2.41	7.27 ± 2.37	-0.273	0.786
AVLT-N3	8.59 ± 2.37	8.27 ± 2.90	0.393	0.696
AVLT-N4	7.28 ± 2.92	7.73 ± 2.83	-0.468	0.641
AVLT-N5	6.98 ± 2.87	6.82 ± 3.76	0.163	0.871
AVLT-N7	14.39 ± 4.95	18.09 ± 6.66	-2.128	0.037a
AVLT-total score	48.46 ± 11.11	56.27 ± 7.35	-2.227	0.030a
DR	13 (23.6)	-	-	-
DN	4 (7.3)	-	-	-
DNP	13 (23.6)	-	-	-
Diabetic angiopathy	1 (1.8)	-	-	-

^aP < 0.05.

Data were presented as means ± SD and n (%). BMI: Body mass index; MMSE: Mini Mental State Examination; MoCA: Montreal Cognitive Assessment; HAMD: Hamilton Depression Rating Scale; HAMA: Hamilton Anxiety Rating Scale; DST: Digital Span Test; TMT: Trail Making Test; SDMT: Symbol Digit Modalities Test; AVLT: Auditory Verbal Learning Test; T2DM: Type 2 diabetes mellitus; HC: Healthy control; DR: Diabetic retinopathy; DN: Diabetic nephropathy; DNP: Diabetic neuropathy.

Table 2 Between‐group differences in hippocampal subfield volume (mm³)

	T2DM (n = 55)	HC (n = 24)	t value	P value
Right Hippocampal tail	639.07 ± 63.17	697.02 ± 66.81	-3.501	0.001a
Right subiculum	479.37 ± 42.52	497.18 ± 42.26	-1.7	0.930
Right CA1	704.05 ± 68.52	755.70 ± 69.03	-2.92	0.005a
Right presubiculum	302.46 ± 29.19	311.54 ± 28.20	-1.281	0.204
Right molecular layer	615.83 ± 52.88	655.06 ± 49.74	-2.998	0.004a
Right GC- DG	327.20 ± 34.45	337.69 ± 30.41	-1.282	0.204
Right CA3	251.50 ± 29.34	268.66 ± 24.81	-2.369	0.020
Right CA4	295.65 ± 31.64	293.96 ± 29.30	0.223	0.824
Right hippocampal fissure	181.26 ± 36.01	170.29 ± 32.34	1.284	0.203
Right parasubiculum	57.89 ± 11.68	56.75 ± 9.34	0.414	0.680
Right fimbria	75.57 ± 17.95	75.62 ± 14.86	-0.01	0.992
Right HATA	55.51 ± 8.67	61.91 ± 7.67	-3.053	0.003a
Right whole hippocampus	3877.00 ± 375.91	3979.17 ± 336.49	-1.151	0.253
Left Hippocampal tail	600.08 ± 78.96	621.35 ± 96.56	-1.024	0.309
Left subiculum	483.49 ± 52.94	498.42 ± 47.40	-1.189	0.238
Left CA1	683.71 ± 79.23	693.66 ± 48.90	-0.537	0.593
Left presubiculum	321.94 ± 38.58	326.52 ± 33.88	-0.495	0.622
Left molecular layer	594.26 ± 56.83	612.20 ± 34.28	-1.351	0.181
Left GC-DG	315.88 ± 35.29	322.36 ± 18.73	-0.816	0.417
Left CA3	231.03 ± 34.77	231.77 ± 31.30	-0.09	0.928
Left CA4	274.92 ± 31.96	279.42 ± 19.50	-0.628	0.532
Left hippocampal fissure	171.75 ± 29.29	150.20 ± 19.06	3.167	0.002a
Left parasubiculum	65.15 ± 11.56	60.78 ± 7.51	1.64	0.105
Left fimbria	85.12 ± 19.10	82.60 ± 19.55	0.538	0.592
Left HATA	57.35 ± 10.69	60.12 ± 8.06	-1.137	0.259
Left whole hippocampus	3748.20 ± 379.16	3786.32 ± 194.61	-0.439	0.662
eTIV	1562922.49 ± 153397.53	1567195.05 ± 120781.08	-0.279	0.781

^aP < 0.05 correction adjusted value had statistical significance.

Adjusted age, sex, education, duration and estimated total intracranial volume. T2DM: Type 2 diabetes mellitus; CA: Cornu ammonis; GC: Granular cell; DG: Dentate gyrus; HATA: Hippocampus amygdala transition area; eTIV: Estimated total intracranial volume.