Prognostic significance of hyponatremia in peripartum cardiomyopathy

Table 1 Clinical profile of peripartum cardiomyopathy patients with and without hyponatraemia, n (%)

Variables	Hyponatremia (n = 90)	Normal serum sodium (n = 101)	P value
Serum sodium, mmol/L	126.7 ± 22.3	139.9 ± 3.2	< 0.001
Age, years	28.5 ± 7.2	30.3 ± 7.2	0.086
NYHA II-IV	66 (73.3)	83 (82.2)	0.141
Unemployment	66 (73.3)	74 (73.3)	0.878
Uneducated	67 (74.4)	67 (66.3)	0.289
Multiparity	65 (72.2)	76 (75.3)	0.757
Twin pregnancy	18 (20.0)	13 (12.9)	0.256
Obesity	1 (1.1)	5 (5.0)	0.270
Stroke	3 (3.3)	1 (1.0)	0.344
History of preeclampsia	17 (18.9)	19 (18.8)	0.960
Systolic BP, mmHg	108 ± 16	110 ± 18	0.255
Diastolic BP, mmHg	74 ± 13	76 ± 15	0.233
Heart rate/min	100 ± 17	100 ± 19	0.789
Ascites	22 (24.4)	27 (26.7)	0.718
Left atrium, mm	45.4 ± 7.0	44.6 ± 6.7	0.465
LV end-diastolic dimension, mm	61.7 ± 9.2	62.5 ± 6.9	0.525
LV ejection fraction at baseline	30.1 ± 8.0	29.8 ± 7.4	0.777
LV ejection fraction at last follow-up	44.2 ± 12.7	42.5 ± 13.3	0.398
Serum creatinine, µmol/L	82.8 ± 29.3	82.5 ± 29.3	0.949
Heart failure treatment
Loop diuretics	77 (85.6)	86 (85.2)	0.762
Thiazide diuretics	1 (1.1)	0	0.471
ACEI or ARB or BB	32 (35.6)	38 (37.6)	0.767
Spironolactone	84 (93.3)	94 (93.1)	0.942

Values were expressed as numbers with percentages in parentheses or as mean ± SD.

NYHA: New York Heart Association functional class; BP: Blood pressure; LV: Left ventricular; ACEI: Angiotensin converting enzyme inhibitors; ARB: Angiotensin receptor blockers; BB: Beta-receptor blockers.

Table 2 Clinical outcomes among patients with and without hyponatraemia, n (%)

Variables	Hyponatremia (n = 90)	Normal serum sodium (n = 101)	P value
Mortality	24 (26.7)	7 (6.9)	< 0.001
Unrecovered left ventricular function	57 (63.3)	73 (72.3)	0.521
Rehospitalization	6 (6.7)	10 (9.9)	0.587

Values were expressed as numbers with percentages in parentheses.