Osmotic stress and mortality in elderly patients with kidney failure: a retrospective study

Figures & data

Table 1 Results from univariate analysis

	Normonatremia	Hypernatremia	Hyponatremia
Patients	128	69	82
Extreme natremia (mmol/L)	139.0±0.3	153.6±0.9	125.5±0.7
Osmotic stress intensitya		70±8	−78±6
Age (years)	82.5±0.5	84.8±0.7b	82.7±0.6
Sex ratio	1.6	1.9	0.9c
Stage of CKD	4	3Bb	3Bc
Severity of AKId	1.6±0.1	2.8±0.3b	2.0±0.2
Infectious disease	29 (23%)	40 (58%)b	30 (37%)c
Autonomia	102 (79%)	28 (41%)b	69 (84%)
Hospital stay (days)	9.7±1.0	15.0±2.4b	12.3±1.3
Death within the first 6 months	21 (22%)	26 (48%)b	19 (29%)

Notes: Results are presented as mean and SD values or as absolute values and percentages. Analysis was performed with Student’s t-tests or chi-squared tests.

a Arbitrary unit (AU).

b P<0.05 between hyper- and normonatremic patients.

c P<0.05 between hypo- and normonatremic patients.

d Defined as the fold increase in baseline SCr.

Abbreviations: AKI, acute kidney injury; CKD, chronic kidney disease; SCr, serum creatinine.

Figure 1 ORs of death between admission and 6 months after discharge from hospital.

Note: Among the factors such as natremia and eGFR, the significant predictive factors included in the multiple logistic regression are only hypernatremia and eGFR ≤15 mL/min/1.73 m² (end-stage renal disease); CI 95%.
Abbreviation: eGFR, estimated glomerular filtration rate.

Table 2 Independent variables retained in the logistic regression equation: hypernatremia and eGFR≤15 mL/min/1.73 m²

Independent variables	OR	P-value signification	OR, CI 95%
			Lower bound	Upper bound
eGFR (mL/min/1.73 m^2)
30<eGFR<60	1.121	0.830	0.395	3.185
15<eGFR≤30	1.859	0.247	0.650	5.313
eGFR≤15	3.910	0.013	1.334	11.462
Natremia
Hyponatremia	1.254	0.535	0.613	2.562
Hypernatremia	3.405	0.001	1.622	7.146

Note: Bold text indicates statistical significance.

Abbreviation: eGFR, estimated glomerular filtration rate.