Changes in corneal nerve morphology and function in patients with dry eyes having type 2 diabetes

Table 1 Demographics and examination findings of the diabetes patients grouped by the duration of type 2 diabetes mellitus with or without dry eye disease

Parameters	DEwDM		P value	DMnDE		P value	DEwDM versus DMnDE P value
	Duration of diabetes ≤ 10 yr	Duration of diabetes > 10 yr		Duration of diabetes ≤ 10 yr	Duration of diabetes > 10 yr		Duration of diabetes ≤ 10 yr	Duration of diabetes > 10 yr
Number [N]	26	30		8	14
Age [yr ± SEM]	56.8 ± 9.3	57.8 ± 6.9	0.660	51.3 ± 8.9	57.1 ± 5.3	0.065	0.146	0.740
Gender			0.126			0.074a	0.257a	1b
Male [N (%)]	13 (50.0)	21 (70.0)		2 (25.0)	10 (71.4)
Female [N (%)]	13 (50.0)	9 (30.0)		6 (75.0)	4 (28.6)
Blood glucose [mmol/L ± SEM]	7.9 ± 3.7	9.6 ± 4.2	0.103	7.8 ± 1.1	9.7 ± 2.8	0.083	0.926	0.989
Duration of diabetes [years ± SEM]	5.9 ± 2.6	17.8 ± 4.8	0.000	8.3 ± 1.7	17.6 ± 5.4	0.000	0.021	0.940
HbA1c [% ± SEM]	7.8 ± 2.3	8.4 ± 1.8	0.257	7.7 ± 1.9	8.1 ± 1.4	0.652	0.921	0.484
BUT [s ± SEM]	4.1 ± 2.5	3.8 ± 2.5	0.586	11.2 ± 7.5	10.0 ± 2.9	0.601	0.000	0.000
Schirmer test [mm ± SEM]	5.9 ± 4.7	3.2 ± 3.4	0.018	18.4 ± 5.9	10.9 ± 6.2	0.012	0.000	0.000
NFL [mm/mm2 ± SEM]	17.653 ± 4.569	15.851 ± 4.881	0.162	20.445 ± 4.036	15.904 ± 5.238	0.047	0.131	0.974
NFD [num/mm2 ± SEM]	33.2 ± 12.1	30.4 ± 8.486	0.323	39.1 ± 12.4	33.9 ± 10.9	0.323	0.240	0.250
NBD [num/mm2 ± SEM]	56.7 ± 25.5	50.0 ± 25.2	0.326	61.7 ± 21.0	43.3 ± 22.4	0.072	0.619	0.401
R1 [ms]	11.8 ± 0.9	12.2 ± 0.8	0.083	10.3 ± 0.5	11.8 ± 1.0	0.001	0.000	0.183

^aP value from exact probability test.

^bP value from Chi-squared test with continuity correction.

BUT: Tear film break-up time; HbA1c: Hemoglobin A1C; OSDI: Ocular surface disease index; Schirmer: Schirmer I test; NFL: Nerve fiber length; NFD: Nerve fiber density; NBD: Nerve branch density; R1: The R1 latency in blink reflex.