Performing Only One Cardiovascular Reflex Test Has a High Positive Predictive Value for Diagnosing Autonomic Neuropathy in Patients with Chronic Renal Failure on Hemodialysis

Figures & data

Table 1 Evaluation of cardiovascular reflex tests

Tests	Normal	Borderline	Abnormal
VR	≥ 1.21	1.11–1.20	≤ 1.10
HRVDDB	≥ 15	11–14	≤ 10
HRRSU	≥ 1.04	1.01–1.03	≤ 1.00
BPRSU	≤ 10	11–29	≥ 30
BPRHE	≥ 16	11–15	≤ 10

VR: Valsalva ratio; HRVDDB: heart rate variation during deep breathing; HRRSU: heart rate response to standing up; BPRSU: blood pressure response to standing up; BPRHE: blood pressure response to hand grip exercise.

Table 2 Patients' characteristics and biochemical parameters

	Autonomic neuropathy
Characteristic	+ (35/40)	– (5/40)	Minimum	Maximum	p value
Age, years	48.74 ± 10.55	42.20 ± 9.25	32	64	0.190
Ferritin, ng/mL	336.00 ± 256.50	386.03 ± 260.83	17	887	0.638
Hemoglobin, g/dL	10.00 ± 1.42	9.92 ± 0.64	5.9	13.8	0.578
Creatinine, mg/dL	8.32 ± 0.91	8.81 ± 1.73	4	11	0.269
Intact parathyroid hormone, pg/mL	269.34 ± 139.42	245.40 ± 159.51	40	461	0.713
Time on hemodialysis, month	44.94 ± 38.39	6.20 ± 49.51	4	188	0.538
Albumin, g/dL	4.46 ±0.54	4.16 ± 0.43	3.3	5.5	0.234
Calcium, mg/dL	9.55 ± 0.60	9.65 ± 0.64	8.6	10.6	0.645
Inorganic phosphorus, mg/dL	5.47 ± 0.79	5.58 ± 0.65	3.8	6.5	0.854
Urea reduction rate	0.654 ± 0.065	0.654 ± 0.061	0.56	0.85	0.399

Table 3. Parasympathetic and Sympathetic Tests Results

	Parasympathetic						Sympathetic
	VR		HRRSU		HRVDDB		BPRSU		BPRHE
	%	N	%	N	%	N	%	N	%	N
Normal	27.5	11	10	4	12.5	5	72.5	29	20	8
Borderline	22.5	9	20	8	10	4	12.5	5	2.5	1
Abnormal	50	20	70	28	77.5	31	15	6	77.5	31
Total	100	40	100	40	100	40	100	40	100	40

VR: Valsalva ratio; HRVDDB: heart rate variation during deep breathing; HRRSU: heart rate response to standing up; BPRSU: blood pressure response to standing up; BPRHE: blood pressure response to hand grip exercise.

Table 4. Parasympathetic and Sympathetic Tests Results

	Parasympathetic			Sympathetic
	VR	HRRSU	HRVDDB	BPRSU	BPRHE
Sensitivity	54	77	86	17	86
Specifity	80	80	80	100	80
PPV	95	97	97	100	97
NPV	20	33	44	14	44

VR: Valsalva ratio; HRVDDB: heart rate variation during deep breathing; HRRSU: heart rate response to standing up; BPRSU: blood pressure response to standing up; BPRHE: blood pressure response to hand grip exercise; PPV: positive predictive value; NPV: negative predictive value.