Blood metal concentrations and cardiac structure and function in total joint arthroplasty patients

Table 1 Characteristics of the study population, n (%)

Characteristic	Total
Age (years)
Mean (SD)	68.8 (9.2)
Median (IQR)	69.0 (63.0, 75.0)
Min, Max	44.0, 93.0
Women	45 (40.9)
Race
Pacific Islander	2 (1.8)
White	108 (98.2)
Smoking history
Current smoker	4 (3.6)
Previous smoker	36 (32.7)
Never smoker	58 (52.7)
History of heart failure	1 (0.9)
Body mass index (kg/m2)
Mean (SD)	30.3 (6.0)
Median (IQR)	30.0 (62.2, 34.3)
Min, Max	18.8, 47.0
Body surface area (m2)
Mean (SD)	2.1 (0.3)
Median (IQR)	2.1 (1.9, 2.2)
Min, Max	1.4, 2.7
Systolic blood pressure, mmHg
Mean (SD)	134.0 (18.9)
Median (IQR)	132.0 (122.0, 144.0)
Min, Max	90.0, 187.0
Diastolic blood pressure, mmHg
Mean (SD)	77.6 (8.8)
Median (IQR)	78.0 (72.0, 83.0)
Min, Max	60.0, 108.0
TJA history
Joint
Hip (total hip arthroplasty)	79 (71.8)
Knee (total knee arthroplasty)	11 (10.0)
Both	20 (18.2)
Revision surgery	59 (53.6)
Years between first TJA surgery and study visit
Mean (SD)	13.4 (5.7)
Median (IQR)	12 (10.0, 16.0)
Min, Max	2.0, 31.0

IQR: Interquartile range; TJA: Total joint arthroplasty.

Table 2 Metal concentrations by sex, n (%)

Metal concentrations (ng/mL)	Total	Men	Women
Detectable chromium,	43 (39.5)	28 (43.8)	15 (33.3)
Mean (SD)	3.8 (4.7)	3.0 (3.5)	5.2 (6.3)
Median (IQR)	1.9 (1.2, 3.8)	1.9 (1.3, 2.9)	2.8 (1.2, 5.8)
Min, max	1.1, 21.4	1.1,18.5	1.2,21.4
Detectable cobalt	51 (46.4)	36 (55.4)	15 (33.3)
Mean (SD)	4.9 (4.3)	5.2 (4.7)	4.1 (3.2)
Median (IQR)	3.7 (1.9, 6.3)	4.1 (2.1, 6.9)	3.2 (1.9, 5.2)
Min, max	1.1, 24.6	1.1, 24.6	1.1, 12
Detectable titanium	89 (80.9)	49 (75.4)	40 (88.9)
Mean (SD)	4.8 (5.1)	4.6 (6.1)	5.1 (3.5)
Median (IQR)	3.0 (2.0, 5.0)	3 (1,5)	4 (3,7)
Min, Max	1.0, 35.0	1,35	1,15

IQR: Interquartile range.

Table 3 Association of metal concentrations with echocardiographic parameters

	Measure available	Mean (SD); Median (interquartile range)	Regression estimates (95%CI)1
Measure (unit)			Chromium	Cobalt	Titanium
LV size and systolic function
2D Biplane LV end-diastolic volume (mL)	100	134.04 (34.14); 129.5 (109, 153)	1.20 (-5.23 to 7.64)	5.09 (0.02-10.17)a	-3.67 (-8.55 to 1.22)
3D LV end-diastolic volume (mL)	95	130.38 (32.14); 126 (110, 147)	0.95 (-4.59 to 6.50)	4.09 (-0.57 to 8.74)a	-1.69 (-6.35 to 2.96)
2D Biplane LV end-systolic volume (mL)	99	50.76 (18.22); 48 (38, 60)	0.44 (-3.05 to 3.92)	3.13 (0.40-5.87)	-1.53 (-4.20 to 1.14)
3D LV end-systolic volume (mL)	94	49.24 (14.2); 48 (38, 57)	0.44 (-1.86 to 2.75)	1.46 (-0.50 to 3.42)	-1.16 (-3.09 to 0.76)
3D LV ejection fraction	94	62.12 (4.34); 62 (60, 65)	-0.10 (-0.88 to 0.68)	-0.51 (-1.17 to 0.15)	0.07 (-0.59 to 0.73)
LV global longitudinal strain	108	-19.74 (2.12); -20 (-21, -19)	-0.15 (-0.55 to 0.26)	-0.27 (-0.60 to 0.07)	-0.38 (-0.70 to 0.06)b
LV stroke volume (mL)	108	94.5 (17.22)/91 (82.5, 105)	-0.28 (-3.43 to 2.87)	1.59 (-0.99 to 4.16)	-2.69 (-5.24 to 0.15)b
LV cardiac output (l/minute)	109	6.12 (1.3); 5.84 (5.22, 6.8)	-0.01 (-0.35 to 0.16)	0.01 (-0.20 to 0.22)	-0.20 (-0.40 to 0.004)a
LV cardiac index (l/minute/m2)	108	2.92 (0.4)/2.82 (2.68,3.16)	0.01 (-0.08 to 0.09)	0.01 (-0.06 to 0.07)	-0.08 (-0.15 to -0.01)b
LV diastolic function
LV diastolic function (normal/abnormal)	110	Normal 42 (38.2)	Reference	Reference	Reference
		Abnormal 68 (61.8)	1.21 (0.78-1.87)	1.14 (0.80-1.62)	0.67 (0.47-0.97)b
Medial E/e' ratio	106	10.76 (3.7)/10 (8.3,12.5)	-0.38 (-1.02 to 0.27)	-0.05 (-0.60 to 0.49)	0.18 (-0.34 to 0.70)
LA biplane vol index (mL/m2)	107	31.32 (9.02); 30 (25, 37)	1.26 (-1.36 to 3.86)	2.72 (0.60-4.84)b	-0.24 ( -2.3 to 1.82)
LA reservoir strain	105	29.9 (6.9); 29.5 (26.2, 33.9)	0.002 (-1.38 to 1.39)	0.083 (-1.06 to 1.22)	1.602 (0.55-2.66)c
Right heart parameters
RV systolic pressure (mmHg)	80	28.34 (5.34); 28 (23.5, 32)	-0.41 (-1.54 to 0.73)	-0.22 (-1.19 to 0.75)	-0.28 (-1.15 to 0.58)
RV size (normal/enlarged)	110	Normal 99 (90)	Reference	Reference	Reference
		Abnormal 11 (10)	1.66 (0.91-3.05)	1.80 (1.08-2.99)b	1.22 (0.74-2.01)
RV basal diameter (mm)	53	40.48 (6.3); 41 (36, 46)	0.37 (-1.18 to 1.92)	1.17 (-0.18 to 2.51)a	-0.17 (-1.42 to 1.08)
Tricuspid annular plane systolic excursion (mm)	91	23.58 (3.7); 23 (21, 26)	-0.34 (-1.21 to 0.53)	0.11 (-0.61 to 0.83)	0.17 (-0.50 to 0.84)
RV Basal Lateral Systolic Strain	34	-25.06 (4.88); -26 (-29, -24)	1.19 (-0.64 to 3.01)	0.40 (-1.50 to 2.29)	-0.59 (-2.12 to 0.94)
Other parameters
Mid ascending thoracic aortic diameter (mm)	82	35.9 (4.08); 36 (33, 38)	0.16 (-0.65 to 0.98)	0.43 (-0.27 to 1.13)	-0.71 (-1.38 to -0.05)b
N terminal pro b-type natriuretic peptide (pg/mL)	109	153.4 (269.3); 85 (42, 138)	-20.47 (-72.32 to 31.38)	10.01 (-32.78 to 52.80)	13.41 (-27.74 to 54.55)
Troponin (ng/mL)	108	13.4 (11.3); 11 (7, 15)	-0.97 (-2.94 to 0.99)	-0.85 (-2.47 to 0.77)	0.22 (-1.34 to 1.78)

¹Estimates from age and sex-adjusted linear regression models indicate the β coefficients as the mean change in echocardiographic measures or cardiac markers per log-unit increase in metal concentrations. Odds ratio estimates from age and sex-adjusted logistic regression models indicate the odds of abnormal findings per log-unit increase in metal concentrations.

^a0.05 ≤ P < 0.1;

^b0.01 ≤ P < 0.05;

^cP < 0.01. LA: left atrium; LV: Left ventricular; RV: right ventricle.