Predictors of Health-Related Quality of Life for Mental Health Status in Patients After Carotid Endarterectomy

Predictors of Health-Related Quality of Life for Mental Health Status in Patients After Carotid Endarterectomy

Original Article Predictors of Health-Related Quality of Life for Mental Health Status in Patients After Carotid Endarterectomy Qingjun Jiang1, Tao L...

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Original Article

Predictors of Health-Related Quality of Life for Mental Health Status in Patients After Carotid Endarterectomy Qingjun Jiang1, Tao Lin2, Lefeng Qu1

OBJECTIVE: To evaluate the health-related quality of life (HRQoL) in patients with carotid stenosis and identify the predictive factors that affect the mental health status in patients after carotid endarterectomy (CEA).

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METHODS: A retrospective study was conducted of all patients presenting with carotid stenosis treated with CEA. Clinical data and demographics were collected for logistic regression analysis. The Short-Form General Health Survey Questionnaire (SF-36) and minimum clinically important difference were used to evaluate the mental health status of patients after CEA.

CONCLUSIONS: Contralateral stenosis, dizziness improvement, and hoarseness may be the predictive factors that affect the mental health status in patients after CEA.

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RESULTS: Between January 2015 and September 2017, a total of 224 patients were enrolled in this study. At baseline, mean SF-36 scores for physical component summary (PCS) (60.1  26.3) and mental component summary (MCS) (59.9  23.1) were significantly lower in patients with carotid disease than the urban population (P < 0.001). After CEA, the SF-36 scores for PCS (62.5  21.7) and MCS (68.4  18.7) were increased. However, only the improvement of MCS achieved minimum clinically important difference. After multiple logistic regression analysis, contralateral stenosis ‡50% (odds ratio [OR] 0.266, 95% confidence interval [CI] 0.141e0.517) and hoarseness (OR 0.160, 95% CI 0.040e0.644) had negative effects on MCS. Dizziness improvement had positive effects on MCS (OR 2.882, 95% CI 1.569e5.298).

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Key words Carotid endarterectomy - Dizziness - Health-related quality of life - Mental health -

Abbreviations and Acronyms CEA: Carotid endarterectomy CHD: Coronary heart disease HRQoL: Health-related quality-of-life MCID: Minimum clinically important difference MCS: Mental component summary PCS: Physical component summary

INTRODUCTION

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trokes have become one of the leading causes of death and disability worldwide.1 Nearly, 80% of stroke cases are ischemic.2 Carotid artery atherosclerosis is a major cause of ischemic stroke. Carotid endarterectomy (CEA) plays a role in the therapy of carotid artery disease. It is well documented that CEA reduces the risk of death and strokes in patients with carotid artery stenosis.3,4 Although the beneficial effect of CEA has been well examined, most of these reports are limited to mortality and morbidity rates. Postoperative health-related quality of life (HRQoL) assessment is recognized by the World Health Organization and numerous authors as an important measure of surgical outcome. The effect of CEA on HRQoL still needs attention. There is a need to identify which characteristics are predictors of impairments or improvements in HRQoL. Clinical improvement after CEA can be claimed with a statistically significant change in HRQoL patient-reported outcome score. The 36-item Short-Form General Health Survey Questionnaire (SF-36) is an accepted questionnaire to evaluate the HRQoL of patients with CEA.5 In addition, an increased SF-36 score may not represent a significantly better recovery process. Thus, the concept of minimum clinically important difference (MCID) has

RLN: Recurrent laryngeal nerve SF-36: Short-Form General Health Survey Questionnaire From the 1Departments of Vascular and Endovascular Surgery and 2Orthopedics, Changzheng Hospital, Second Military Medical University, Shanghai, China To whom correspondence should be addressed: Lefeng Qu, M.D., Ph.D. [E-mail: [email protected]] Qingjun Jiang and Tao Lin contributed equally to this work. Citation: World Neurosurg. (2019). https://doi.org/10.1016/j.wneu.2019.02.060 Journal homepage: www.journals.elsevier.com/world-neurosurgery Available online: www.sciencedirect.com 1878-8750/$ - see front matter ª 2019 Elsevier Inc. All rights reserved.

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Table 1. Normative Value for Each Component of SF-36 Score and Minimum Clinically Important Difference Values Used in This Study Physical Component Summary

Mental Component Summary

78.5  19.6

80.7  16.1

8.2

6.0

Normal population MCID

Data are presented as mean  standard deviation or %. MCID, minimum clinically important difference.

been introduced. The MCID is defined as “smallest amount of improvement that is clinically relevant to the individual patient for various outcome measures.”6 MCID values used for SF-36 have been established by previous study.7 A low level of HRQoL among carotid stenosis patients was most pronounced for physical functioning, but mental health was also affected. Prior studies have reported the HRQoL after CEA,5,8 but these studies focus on overall HRQoL. Few studies have examined how the patients’ mental health is affected by the procedure. The purpose of this study was to assess the HRQoL in patients after CEA and to identify the potential predictive factors that influence the HRQoL.

Table 2. Baseline Characteristics of Patients Characteristic Demographics

Value (n [ 224) 224

Gender (male, %)

184 (82.1%)

Age (years)

67.4  6.9

Medical history Hypertension

92 (41.1%)

Dyslipidemia

44 (19.6%)

Diabetes

56 (25.0%)

Chronic heart disease

40 (17.9%)

Current smoker

92 (41.1%)

Lower extremity arterial stenosis

32 (14.3%)

Cerebrovascular history Symptomatic carotid disease

128 (57.1%)

Prior stroke

36 (16.1%)

Prior TIA

68 (30.4%)

Stenosis

82.3%  9.6%

Contralateral stenosis >50% Data are presented as mean  standard deviation or %. TIA, transient ischemic attack.

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60 (26.8%)

METHODS A post hoc analysis was undertaken of all patients presenting with carotid stenosis treated with CEA between January 2015 and September 2017. All operations were performed by 1 vascular surgeon using eversion techniques. All patients had the operation performed on a single side only. No patient was enrolled twice. Inclusion criteria were as follows: 1) patients who underwent CEA from September 2015 to September 2017 at the Shanghai Changzheng Hospital; 2) at least 1 years follow-up; 3) completed the SF-36 questionnaire before undergoing CEA and again at 1 year afterward. Exclusion criteria were as follows: 1) patients who underwent bilateral CEA; 2) patients without complete preoperative and postoperative HRQoL data. Data Collection The data collected included gender, symptoms, preoperative stroke, preoperative Transient ischemic attack (TIA), smoking, hypertension, hyperlipidemia, diabetes, hyperhomocysteinemia (HHcy), lower extremity arterial stenosis, coronary heart disease (CHD), contralateral stenosis, surgical side, property of plaque, clamping time, dizziness improvement, postoperative complications (hoarseness and incision numbness), and SF-36 score preoperatively and at final follow-up. Measures of HRQoL The SF-36 has become the most widely used measure of general health in clinical studies throughout the world. It currently generates 8 dimensions and 2 summary scales for overall physical and mental health. It has been well validated in patients with cardiovascular disease, in stroke patients, and in the general population.9,10 In this study, patients were assessed the overall physical component summary (PCS) and mental component summary (MCS). Scores for the SF-36 range from 0 to 100, with higher scores indicating better health status. The HRQoL outcomes were assessed at baseline and at 1-year follow-up. The MCID values and normative values for each component of the SF-36 score are summarized in Table 1. To assess the recovery processes, we categorized the patients into 2 groups based on change of SF-36 scores from baseline to 1year follow-up: 1) improvement: Diff  1 MCID; 2) no change: Diff < 1 MCID. Diff ¼

SF1year  SFbaseline MCID

Statistical Analysis Statistical analysis was performed by SPSS 22.0 for Windows software (IBM Corp, Armonk, New York, USA). The mean values are presented as mean  standard deviation. The Mann-Whitney U test was used to determine differences between groups. Univariate analysis was performed to identify factors associated with MCS using a c2 test. The multivariate logistic regression model selection was based on the forward method. Odds ratios (OR) with corresponding 95% confidence intervals (95% CIs) along with P values were calculated. A P value <0.05 was considered statistically significant for all analyses.

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Figure 1. Flow chart of selection of patients. CEA, carotid endarterectomy; HRQoL, health-related quality of life.

RESULTS Characteristics of Patients and Key Clinical Outcomes The baseline patient characteristics and preoperative details are shown in Table 2. There were 265 consecutive patients who had undergone CEA between January 2015 and September 2017. Forty-one patients were excluded (Figure 1). In total, 224 patients were enrolled in this study, of whom 184 were male. The mean age of the patients was 67.4  6.9 years, and the mean stenosis rate was 82.3%. Overall, 57.1% of patients were symptomatic. There were no perioperative deaths. There were two minor thrombotic strokes, 1 minor hemorrhagic stroke, and 9 hematomas not requiring surgical drainage. Baseline and 1-Year Follow-Up HRQoL Outcomes of MCS and PCS The MCID values7 and normative values11 of the SF-36 score are summarized in Table 3. At baseline, mean SF-36 scores for PCS (60.1  26.3) and MCS (59.9  23.1) were significantly lower in patients

with carotid disease than the urban population (P < 0.001). The 1year follow-up results showed that the SF-36 scores for PCS (62.5  21.7) and MCS (68.4  18.7) were increased after the CEA operation. However, only the improvement of MCS achieved MCID. According to the improvement of MCS, there were 152 patients in the improvement group and 72 in the nonimprovement group (Table 4). There was no difference in PCS and MCS between the 2 groups before operation. Factors Associated with Mental Components of HRQoL Eighteen potential predictive factors were analyzed. Table 5 shows the variables for which statistically significant differences in the MCS

Table 4. Baseline and 1-Year Follow-Up Results of SF-36 Scores Between Improvement Group and Nonimprovement Group Improvement, n [ 152

Nonimprovement, n [ 72

P Value

Physical component summary

60.6  25.9

58.9  27.3

0.65

Mental component summary

60.1  22.9

59.5  23.7

0.86

Physical component summary

61.9  22.1

63.7  21.0

0.56

Mental component summary

71.6  19.3

61.7  15.6

0.0001

Score

Table 3. Baseline and 1-Year Follow-Up Results of SF-36 Score Physical Component Summary

Mental Component Summary

Baseline scores

60.1  26.3

59.9  23.1

1-year scores

Factor

62.5  21.7

68.4  18.7

P value

0.29

0.0001

Change

<1 MCID

>1 MCID

Data are presented as mean  standard deviation or %. SF-36, Short-Form General Health Survey Questionnaire; MCID, minimum clinically important difference.

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Baseline

1-year

SF-36, Short-Form General Health Survey Questionnaire.

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Table 5. Factors Associated with Mental Components of HRQoL Factor Number of patients

Improvement, n (%)

Nonimprovement, n (%)

152 (67.9)

72 (32.1)

P Value

Gender

Table 5. Continued Improvement, n (%)

Nonimprovement, n (%)

Left

80 (69.0)

36 (31.0)

Right

72 (66.7)

36 (33.3)

Yes

88 (71.0)

36 (29.0)

No

64 (64.0)

36 (36.0)

Factor

P Value 0.713

Ulcerative plaque

Male

120 (65.2)

64 (34.8)

Female

32 (80.0)

8 (20.0)

Yes

92 (71.9)

36 (28.1)

No

60 (62.5)

36 (37.5)

Yes

28 (77.8)

8 (22.2)

No

124 (66.0)

64 (34.0)

Yes

52 (76.5)

16 (23.5)

No

100 (64.1)

56 (35.9)

Yes

56 (60.9)

36 (39.1)

No

96 (72.7)

36 (27.3)

0.07

Symptomatic

0.267

Clamping time (minutes) 0.137

Preoperative stroke

15

36 (75.0)

12 (25.0)

<15

116 (65.9)

60 (34.1)

0.232

Dizziness improvement 0.164

Preoperative TIA

Yes

144 (94.7)

8 (5.3)

No

8 (11.1)

64 (88.9)

Yes

12 (37.5)

20 (62.5)

No

140 (72.9)

52 (27.1)

Yes

20 (26.3)

56 (73.7)

No

136 (91.9)

12 (8.1)

0.001

Hoarseness 0.068

Smoking

0.001

Incisional numbness 0.062

Contralateral stenosis >50% Yes

28 (46.7)

32 (53.3)

No

124 (75.6)

40 (24.4)

Yes

36 (81.8)

8 (18.2)

No

116 (64.4)

64 (35.6)

Yes

76 (82.6)

16 (17.4)

No

76 (57.6)

56 (42.4)

High

48 (80.0)

12 (20.0)

Normal

104 (63.4)

60 (36.6)

0.001

Hyperlipidemia 0.027

Hypertension 0.001

HHcy 0.019

Diabetes Yes

52 (92.9)

4 (7.1)

No

100 (59.5)

68 (40.5)

0.001

Lower extremity arterial stenosis Yes

20 (62.5)

12 (37.5)

No

140 (72.9)

52 (27.1)

Yes

28 (70.0)

12 (30.0)

No

124 (67.4)

60 (32.6)

0.227

0.001

HRQoL, health-related quality of life; TIA, transient ischemic attack; HHcy, hyperhomocysteinemia.

were found. There were no significant differences in the MCS score relating to gender, symptom, preoperative stroke, preoperative TIA, smoking, lower extremity arterial stenosis, CHD, surgical side, the property of plaque, or clamping time. Eight variables (contralateral stenosis, hyperlipidemia, hypertension, HHcy, diabetes, dizziness improvement, hoarseness, and incisional numbness) obtained statistical significance (P < 0.05) in the univariate logistic regression models. Factors Associated with Mental Components of HRQoL in Multivariate Analysis According to multivariate logistic regression analysis, contralateral stenosis 50% (OR 0.266, 95% CI 0.141e0.517), dizziness improvement (OR 2.882, 95% CI 1.569e5.298), and hoarseness (OR 0.160, 95% CI 0.040e0.644) were included in the multivariate logistic regression model (Table 6). Other variables including hyperlipidemia, hypertension, HHcy, diabetes, and incisional numbness were excluded from the multivariate logistic regression model.

Chronic heart disease 0.749

Surgical side Continues

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DISCUSSION CEA plays a major role in stroke prevention in patients with carotid artery stenosis. Carotid disease also causes impairment of physical, cognitive, and mental health, which negatively affects HRQoL. In this study, we assessed the SF-36 scores in patients after CEA and further described the changes in 2 domains (PCS

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Table 6. Factors Associated with Mental Components of HRQoL in Multivariate Logistic Regression Analysis Odds Ratio (95% Confidence Interval)

P Value

50%

0.266 (0.141e0.517)

0.011

<50%

1

Factor Contralateral stenosis

Dizziness improvement Yes

2.882 (1.569e5.298)

No

1

0.0001

Hoarseness Yes

0.160 (0.040e0.644)

No

1

0.010

and MCS) using the MCID. When assessing the preoperative HRQoL, we found, as could be expected, that patients with carotid disease had significantly lower mean SF-36 scores than the general population, which was consistent with previous studies.8,12 At 1-year follow-up after CEA, there was both statistically and clinically significant improvement in the MCS domain. In multivariate analysis, contralateral stenosis, dizziness improvement, and hoarseness were the predictive factors that affected the MCS in patients after CEA. Previous studies have assessed HRQoL after CEA, with varying results. Not surprisingly, several studies have reported no improvement in HRQoL after CEA.13,14 Other studies have reported significant improvement in HRQoL after CEA.8,15 The reasons for the varying results might be the different questionnaires, study designs, small sample sizes, and observer bias. To reduce these biases, we used the SF-36 questionnaire, which has been well validated in vascular surgery. Furthermore, we used MCID instead of SF-36 score to evaluate the HRQoL change. At 1-year follow-up after CEA, MCS improved significantly but PCS did not improve, which is worth considering. HRQoL has been evaluated in numerous studies for the treatment of symptomatic vascular disease. For symptomatic conditions such as chronic stable angina8,16 and lower extremity claudication,17 patients generally experience symptom relief immediately after revascularization. However, in this study, the patients had carotid artery stenosis, which is generally clinically silent. This is a major distinction from studies that have compared the HRQoL. Anxiety, depression, and fatigue are common in carotid stenosis patients.18,19 These mental problems are all related to

REFERENCES 1. Rosenfield K, Matsumura JS, Chaturvedi S, et al. Randomized trial of stent versus surgery for asymptomatic carotid stenosis. N Engl J Med. 2016; 374:1011-1020. 2. Favate AS, Younger DS. Epidemiology of ischemic stroke. Neurol Clin. 2016;34:967-980.

HRQoL. One study found significantly less anxiety and depression after CEA.12 In addition, patients only perceived themselves as chronically ill but mentally healthy after they underwent CEA. These points may lead to improvement in MCS but not in PCS. In patients with contralateral stenosis, even after CEA, psychological problems such as anxiety and fatigue still exist. In the present research, contralateral stenosis 50% was found to be associated with negative effects on MCS (OR 3.761, 95% CI 1. 936e7.074). Dizziness is a common symptom in patients with carotid stenosis and seriously affects their HRQoL. Dizziness may result from decreased cerebral perfusion due to carotid stenosis.20 One study showed that patients with carotid stenosis who experienced dizziness had significantly lower SF-36 scores and that carotid revascularization can significantly improve HRQoL in patients with dizziness.21 In the present study, 152 patients experienced dizziness improvement after CEA. Of those, 144 (94.7%) patients achieved MCID in MCS. This result further confirm the positive impact of dizziness improvement on MCS (OR 2.882, 95% CI 1.569e5.298). Cranial nerve injury is the most common neurologic complication of CEA and can cause significant chronic disability.22 A meta-analysis revealed that the vagus nerve was the most frequently injured cranial nerve after CEA.23 The recurrent laryngeal nerve (RLN) originates from the thoracic segment of the vagal trunk. The RLN can be injured by surgical dissection, electrocautery, clamp injury, or compression by a postoperative hematoma.22 Hoarseness is the main manifestation of RLN injury. In this study, the incidence of hoarseness was 14.3% of patients; of those, only 1 (0.4%) patient experienced vocal cord palsy, confirmed by laryngoscope. The results of the present study show that patients who experienced hoarseness were more likely to have no improvement in MCS (OR 0.160, 95% CI 0.040e0.644). This study focused on the MCS in patients after CEA. Some factors—contralateral stenosis, dizziness improvement, and hoarseness—were the predictive factors affecting the MCS. Despite these findings, this study had several limitations. Although the data were collected prospectively, the analysis was retrospective in nature. In addition, the number of patients was relatively small. Further validation studies in larger populations are warranted.

CONCLUSION To evaluate the mental health status of patients after CEA, SF-36 combined with MCID is a more accurate method. Contralateral stenosis, dizziness improvement, and hoarseness may be the predictive factors that affect the mental health status in patients after CEA.

3. Brott TG, Howard G, Roubin GS, et al. Long-term results of stenting versus endarterectomy for carotid-artery stenosis. N Engl J Med. 2016;374: 1021-1031.

4. Halliday A, Harrison M, Hayter E, et al. 10-year stroke prevention after successful carotid endarterectomy for asymptomatic stenosis (ACST-1): A

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multicentre randomised trial. Lancet. 2010;376: 1074-1084.

5. Cohen DJ, Stolker JM, Wang K, et al. Healthrelated quality of life after carotid stenting versus carotid endarterectomy: Results from CREST (Carotid Revascularization Endarterectomy Versus Stenting Trial). J Am Coll Cardiol. 2011;58:1557-1565.

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6. Jaeschke R, Singer J, Guyatt GH. Measurement of .health status: Ascertaining the minimal clinically important difference. Control Clin Trials. 1989;10: 407-415.

13. Parker JC, Smarr KL, Granberg BW, et al. Neuropsychological parameters of carotid endarterectomy: A two-year prospective analysis. J Consult Clin Psychol. 1986;54:676-681.

7. Xue C, Bian L, Xie YS, et al. Low fT3 is associated with diminished health-related quality of life in patients with acute coronary syndrome treated with drug-eluting stent: A longitudinal observational study. Oncotarget. 2017;8:94580-94590.

14. Lloyd AJ, Hayes PD, London NJ, et al. Does carotid endarterectomy lead to a decline in cognitive function or health related quality of life? J Clin Exp Neuropsychol. 2004;26:817-825.

8. Dardik A, Minor J, Watson C, et al. Improved quality of life among patients with symptomatic carotid artery disease undergoing carotid endarterectomy. J Vasc Surg. 2001;33:329-333. 9. Ware JJ, Sherbourne CD. The MOS 36-item shortform health survey (SF-36). I. Conceptual framework and item selection. Med Care. 1992;30: 473-483. 10. Stolker JM, Mahoney EM, Safley DM, et al. Healthrelated quality of life following carotid stenting versus endarterectomy: Results from the SAPPHIRE (Stenting and Angioplasty with Protection in Patients at HIgh Risk for Endarterectomy) trial. JACC Cardiovasc Interv. 2010;3:515-523. 11. Longchao Z, Zhijun L, Yan H, et al. Survey on the applicability of SF-36 version-2 (SF-36v2) in assessment quality of life among urban residents in Chengdu city. Zhonghua Yu Fang Yi Xue Za Zhi. 2014;48:370-374. 12. Vlajinac H, Marinkovic J, Maksimovic M, et al. Health-related quality of life among patients with symptomatic carotid disease. Postgrad Med J. 2013; 89:8-13.

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15. Kazmierski P, Kasielska A, Bogusiak K, et al. Influence of internal carotid endarterectomy on patients’ life quality. Pol Przegl Chir. 2012;84:17-22. 16. Abah U, Dunne M, Cook A, et al. Does quality of life improve in octogenarians following cardiac surgery? A systematic review. Bmj Open. 2015;5: e6904. 17. Mays RJ, Casserly IP, Kohrt WM, et al. Assessment of functional status and quality of life in claudication. J Vasc Surg. 2011;53:1410-1421. 18. Goodwin RD, Devanand DP. Stroke, depression, and functional health outcomes among adults in the community. J Geriatr Psychiatry Neurol. 2008;21: 41-46. 19. Luijendijk HJ, Stricker BH, Wieberdink RG, et al. Transient ischemic attack and incident depression. Stroke. 2011;42:1857-1861. 20. Chen H, Shi Z, Feng H, et al. The relationship between dizziness and cervical artery stenosis. Neuroreport. 2015;26:1112-1118.

21. Hsu LC, Chang FC, Teng MM, et al. Impact of carotid stenting in dizzy patients with carotid stenosis. J Chin Med Assoc. 2014;77:403-408. 22. Hye RJ, Mackey A, Hill MD, et al. Incidence, outcomes, and effect on quality of life of cranial nerve injury in the Carotid Revascularization Endarterectomy versus Stenting Trial. J Vasc Surg. 2015;61:1208-1214. 23. Kakisis JD, Antonopoulos CN, Mantas G, et al. Cranial nerve injury after carotid endarterectomy: Incidence, risk factors, and time trends. Eur J Vasc Endovasc Surg. 2017;53:320-335.

Conflict of interest statement: This work was supported by the National Natural Science Foundation of China (grant numbers 81870347); National Natural Science Foundation of China (grant numbers 81700408); Science and Technology Commission of Shanghai, China (grant numbers 16411966500); and Special Professor Fund of University in Shanghai, China (grant numbers GZ2016008). Received 18 December 2018; accepted 16 February 2019 Citation: World Neurosurg. (2019). https://doi.org/10.1016/j.wneu.2019.02.060 Journal homepage: www.journals.elsevier.com/worldneurosurgery Available online: www.sciencedirect.com 1878-8750/$ - see front matter ª 2019 Elsevier Inc. All rights reserved.

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