Keywords
thyroidectomy - urinary tract infection - morbidity - mortality
Introduction
Thyroidectomy is a common surgical procedure used to manage both benign and malignant
thyroid pathologies. As the incidence of thyroid cancer continues to rise at a rate
of over 5% annually, the increasing demand for thyroidectomies could pose a significant
surgical burden.[1] Thyroidectomy is generally well-tolerated with a minimal morbidity rate.[2] However, complications such as recurrent laryngeal nerve injury, hematoma, and postoperative
hypocalcemia may occur.[3]
Urinary tract infections (UTIs) represent a well-known postoperative complication
across multiple surgical subspecialties. For instance, UTIs account for 40% of all
healthcare-associated infections, making it a significant concern for healthcare professionals.[4] In addition to complicating prognosis for patients, UTIs also incur a significant
financial burden. In fact, UTIs have cost over 450 million USD and resulted in more
than 13,000 deaths annually in the last decades.[4]
[5]
[6] Given these serious implications, it is imperative to mitigate their risk among
surgery patients and optimize care for patients with UTIs to reduce associated morbidity
and mortality.
The incidence of postoperative UTIs among patients undergoing thyroidectomy is rare,
with only 0.28% of cases reported in the literature.[7] As a result, there has been a lack of research on the risk factors and outcomes
of UTIs in this patient population. To fill this gap, our study aims to evaluate the
incidence, underlying risk factors, and postoperative outcomes of 30-day postoperative
UTIs in adult patients undergoing thyroidectomy.
Methods
This retrospective cohort study was conducted in adherence with the Strengthening
the Reporting of Observational Studies in Epidemiology (STROBE) reporting guideline,
utilizing the American College of Surgeons National Surgical Quality Improvement Program
(ACS-NSQIP) database. The ACS-NSQIP partnering hospitals collect standardized, audited
clinical data on patient characteristics, preoperative and intraoperative details,
and postoperative complications for a predetermined, random sample of their patients.
Postoperative outcomes are evaluated by qualified surgical clinical reviewers at each
participating center for up to 30 days after the index operation, regardless of patient
discharge status. These reviewers assess the patients' medical records, contact the
involved clinicians, and reach out to patients as necessary to obtain the required
ACS-NSQIP data elements. As this study utilized already deidentified data, it was
exempted from review by the Ethics Review Committee at the Aga Khan University in
Pakistan (reference ID: 2021–6794–19517).
Population
Our study population consisted of all adult patients (age ≥ 18 years) who underwent
partial, subtotal/total, or completion thyroidectomies for any indication between
January 1st, 2005, and December 31st, 2019. We identified these patients using current procedural terminology (CPT) codes
([Table 1]). We excluded patients who underwent emergency surgery and those with primary surgical
specialty coded other than general surgery or otolaryngology.
Table 1
Included current procedural terminology codes
Procedure
|
CPT codes
|
Partial thyroidectomy
|
60210: Partial total lobectomy
60212: Partial total lobectomy with contralateral subtotal lobectomy
60220: Total thyroid lobectomy, unilateral; with or without isthmusectomy
|
Total/subtotal thyroidectomy
|
60225: Total thyroid lobectomy, unilateral; with contralateral subtotal lobectomy,
including isthmusectomy
60240: Thyroidectomy, total or complete
60252: Thyroidectomy, total or subtotal for malignancy; with limited neck dissection
60254: Thyroidectomy, total or subtotal for malignancy; with radical neck dissection
60270: Thyroidectomy, including substernal thyroid; sternal split or transthoracic
approach
60271: Thyroidectomy, including substernal thyroid; cervical approach
|
Completion thyroidectomy
|
60260: Thyroidectomy, removal of all remaining thyroid tissue following previous removal
of a portion of thyroid
|
Abbreviation: CPT, current procedural terminology.
Measures
In the present study, both demographic and preoperative comorbidity variables were
examined. Age, gender, and race were the demographic variables, while preoperative
comorbidities included diabetes mellitus, functional health status, current smoking
status, ventilator dependency, chronic obstructive pulmonary disease (COPD), congestive
heart failure, hypertension necessitating medication, acute renal failure, dialysis,
and steroid/immunosuppressant use for chronic conditions. Additionally, surgical variables
such as American Society of Anesthesiologists (ASA) classification, wound classification,
surgical indication, type of thyroidectomy, inpatient/outpatient status, and operative
time were analyzed. The surgical indications were further classified as benign or
malignant using the International Classification of Diseases, Ninth and Tenth Revisions
(ICD-9-CM and ICD-10-CM, respectively).
Outcomes
The primary outcome of interest in this study was the development of UTIs within 30
days after the operation. Index markers for clinically diagnosing UTI included pyrexia
(> 38° C), urinary urgency, frequency, dysuria, or suprapubic discomfort in the presence
of a urine culture containing more than 100,000 colonies/mL and a maximum of 2 organism
species. Alternatively, patients were required to have 2 of the aforementioned symptoms
along with a positive dipstick test for leukocyte esterase or nitrates, pyuria greater
than 10 white blood cells/mm3 or greater than 3 white blood cells/hpf of unspun urine, organisms visualized on
urine gram stain, 2 urine cultures containing the same uropathogen >100 colonies/mL,
or one urine culture containing less than 100,000 colonies/mL in a patient who had
been prescribed an antibiotic.
Secondary outcomes of interest included all-cause mortality, surgical site infections
(SSIs; superficial, deep, or organ/space), sepsis, septic shock, wound disruption,
pneumonia, cerebrovascular accident (CVA) or stroke, cardiac arrest requiring cardiopulmonary
resuscitation, myocardial infarction, unplanned reintubation, prolonged postoperative
ventilator dependence of > 48 hours, progressive renal insufficiency, acute renal
failure requiring dialysis, pulmonary embolism, deep venous thrombosis, and unplanned
reoperation. Additionally, unplanned reoperation and prolonged length of stay (> 2
days) were also evaluated. Unplanned reoperation was not limited to the index hospital.
This study further analyzed composites of these outcomes, namely any complication,
infectious and non-infectious complications.
Statistical Analysis
Patients were first subdivided into UTI and non-UTI groups, and descriptive statistics
were reported. Continuous variables were confirmed to have non-parametric distribution
using the Kolmogorov-Smirnov test and were reported using median and interquartile
ranges (IQRs), and then compared between the two groups using the Mann-Whitney U test.
Categorical variables were described using frequencies and percentages and were compared
between the groups using the χ2 tests or Fisher exact tests, as appropriate.
To further assess the factors associated with postoperative UTIs in thyroidectomy
patients, binary logistic regression models were utilized. Similarly, multivariable
models were computed for secondary outcomes, with the development of UTI as the main
explanatory variable. Clinically relevant covariates occurring prior to the outcomes
and with p < 0.25 on univariate analyses were used to adjust these regression models.
All statistical analyses were performed using two-sided tests with α < 0.05 as the
threshold for significance. Adjusted odds ratios (ORs) along with 95% confidence intervals
(CIs) were reported. Missing data were included in flowcharts and summary tables,
which allowed denominators to remain consistent in calculations. The software used
for the analyses was the IBM SPSS Statistics for Windows, version 23.0 (IBM Corp.,
Armonk, NY USA).
Results
A total of 180,373 thyroidectomy cases were included in the study ([Fig. 1]), with only 0.28% of patients developing a postoperative UTI. Among these cases,
most were female patients, and other sociodemographic characteristics are described
in [Table 2]. The UTI and non-UTI groups were compared, and the univariate analysis demonstrated
several factors to be significantly associated with the incidence of UTIs. These factors
included a higher ASA classification, dependent functional health status, diabetes
mellitus, chronic steroid therapy, longer operative time, inpatient thyroidectomy,
and wound contamination. Moreover, the composite pulmonary and cardiovascular disorders,
as well as each of their individual components, were also significantly linked to
the occurrence of UTIs.
Fig. 1 Cohort creation. Abbreviations: ACS-NSQIP, American College of Surgeons National Surgical Quality Improvement Program;
PUF, participant use data file.
Table 2
Baseline characteristics, comorbidities, and operative variables stratified by urinary
tract infection status
Variable
|
No UTI
N = 179,883
|
UTI
N = 490
|
p-value
|
Age, in years
|
|
|
< 0.001
|
18–40
|
41,878 (23.3%)
|
69 (14.1%)
|
40–60
|
80,993 (45.1%)
|
155 (31.7%)
|
> 60
|
56,858 (31.6%)
|
265 (54.2%)
|
Missing
|
154
|
1
|
Age/years*
|
52.0 (23.0)
|
61.0 (23.0)
|
< 0.001
|
Gender
|
|
|
0.016
|
Female
|
142,944 (79.5%)
|
411 (83.9%)
|
Male
|
36,939 (20.5%)
|
79 (16.1%)
|
Race
|
|
|
0.511
|
White
|
121,636 (78.5%)
|
340 (80.6%)
|
Black
|
23,362 (15.1%)
|
54 (12.8%)
|
American Indian or Alaska Native
|
699 (0.5%)
|
3 (0.7%)
|
Asian, Native Hawaiian, or Pacific Islander
|
9,182 (5.9%)
|
25 (5.9%)
|
Missing
|
25,004
|
68
|
BMI (kg/m2)
|
|
|
0.133
|
Healthy (18.5-24.9)
|
43,195 (24.2%)
|
108 (22.3%)
|
Underweight (< 18.5)
|
1,876 (1.1%)
|
10 (2.1%)
|
Overweight (25.0–29.9)
|
53,829 (30.1%)
|
151 (31.1%)
|
Obese (30 or higher)
|
79,676 (44.6%)
|
216 (44.5%)
|
Missing
|
1,307
|
5
|
BMI (kg/m2)*
|
29.1 (9.4)
|
29.1 (9.1)
|
0.765
|
ASA classification
|
|
|
< 0.001
|
ASA 1–2
|
123,710 (68.9%)
|
251 (51.4%)
|
ASA 3–5
|
55,869 (31.1%)
|
237 (48.6%)
|
Missing
|
304
|
2
|
Functional health status
|
|
|
< 0.001
|
Independent
|
178,247 (99.5%)
|
460 (95.4%)
|
Partially independent
|
791 (0.4%)
|
15 (3.1%)
|
Totally independent
|
105 (0.1%)
|
7 (1.5%)
|
Missing
|
740
|
8
|
Current smoker
|
25,604 (14.2%)
|
60 (12.2%)
|
0.208
|
Diabetes mellitus
|
23,139 (12.9%)
|
97 (19.8%)
|
< 0.001
|
Pulmonary disease
|
3,865 (2.1%)
|
35 (7.1%)
|
< 0.001
|
COPD
|
3,823 (2.1%)
|
30 (6.1%)
|
< 0.001
|
Ventilator dependence
|
48 (0.0%)
|
7 (1.4%)
|
< 0.001
|
Cardiovascular disease
|
68,273 (38.0%)
|
258 (52.7%)
|
< 0.001
|
Hypertension
|
68,184 (37.9%)
|
258 (52.7%)
|
< 0.001
|
Congestive heart failure
|
408 (0.2%)
|
6 (1.2%)
|
0.001
|
Renal disease
|
729 (0.4%)
|
2 (0.4%)
|
0.727
|
Acute renal failure
|
72 (0.0%)
|
1 (0.2%)
|
0.180
|
Currently on dialysis
|
695 (0.4%)
|
1 (0.2%)
|
1.000
|
Chronic steroid therapy
|
3,990 (2.2%)
|
25 (5.1%)
|
< 0.001
|
Wound classification
|
|
|
0.009
|
Clean
|
175,857 (97.8%)
|
468 (95.5%)
|
Clean contaminated
|
3,399 (1.9%)
|
16 (3.3%)
|
Contaminated
|
589 (0.3%)
|
5 (1%)
|
Dirty/infected
|
38 (0.0%)
|
1 (0.2%)
|
Surgical Indication
|
|
|
0.912
|
Benign
|
119,986 (66.7%)
|
328 (66.9%)
|
Malignant
|
59,897 (33.3%)
|
162 (33.1%)
|
Type of thyroidectomy
|
|
|
0.223
|
Partial
|
64,756 (36%)
|
159 (32.4%)
|
Total
|
107,650 (59.8%)
|
307 (62.7%)
|
Completion
|
7,477 (4.2%)
|
24 (4.9%)
|
Inpatient/Outpatient status
|
|
|
< 0.001
|
Outpatient
|
113,286 (63.0%)
|
250 (51.0%)
|
Inpatient
|
66,597 (37.0%)
|
240 (49.0%)
|
Operative time/minutes
|
|
|
0.001
|
Less than 60
|
21,405 (11.9%)
|
54 (11%)
|
60–90
|
47,314 (26.3%)
|
126 (25.7%)
|
90–120
|
42,730 (23.8%)
|
88 (18%)
|
120–150
|
28,447 (15.8%)
|
79 (16.1%)
|
> 150
|
39,970 (22.2%)
|
143 (29.2%)
|
Missing
|
17
|
0
|
Operative time/minutes*
|
103.0 (68.0)
|
111.0 (85.0)
|
0.003
|
Abbreviations: ASA, American Society of Anesthesiologists; BMI, body mass index; COPD, chronic obstructive
pulmonary disease; UTI, urinary tract infection.
Note: * Reported with median and interquartile range; percentages are presented in columns.
After adjusting for clinically relevant covariates, the multivariable logistic regression
analysis identified several risk factors associated with the development of postoperative
UTI among thyroidectomy patients. These included age > 60 years (adjusted odd ratio
[OR]: 2.187, 95% CI: 1.618–2.956), female gender (OR: 1.767, 95% CI: 1.372–2.278),
ASA classifications 3 to 5 (OR: 1.463, 95% CI: 1.185–1.805), partially (OR: 4.267,
95% CI: 2.510–7.253) or totally dependent functional health status (OR: 9.658, 95%
CI: 4.170–22.370), pulmonary disease (OR: 1.907, 95% CI: 1.295–2.808), chronic steroid
therapy (OR 1.649, 95% CI 1.076–2.527), inpatient procedure (OR: 1.507, 95% CI: 1.251–1.814),
and operative time greater than 150 minutes (OR: 1.449, 95% CI: 1.027–2.044) ([Table 3]).
Table 3
Multivariable logistic regression analyses for risk factors of 30-day urinary tract
infection
Variable
|
Adjusted OR
|
p-value
|
Age/years
|
|
|
18–40
|
Reference
|
–
|
40–60
|
1,078 (0.803–1,445)
|
0.618
|
> 60
|
2,187 (1,618–2,956)
|
< 0.001
|
Gender
|
|
|
Female
|
Reference
|
–
|
Male
|
0.566 (0.439–0.729)
|
< 0.001
|
BMI (kg/m2)
|
|
|
Healthy (18.5–24.9)
|
Reference
|
–
|
Underweight (< 18.5)
|
1,892 (0.982–3.645)
|
0.057
|
Overweight (25.0–29.9)
|
1,048 (0.813–1,351)
|
0.716
|
Obese (30 or higher)
|
0.901 (0.704–1,153)
|
0.408
|
ASA classification
|
|
|
ASA 1–2
|
Reference
|
–
|
ASA 3–5
|
1,463 (1,185–1,805)
|
< 0.001
|
Functional health status
|
|
|
Independent
|
Reference
|
–
|
Partially independent
|
4,267 (2,510–7,253)
|
< 0.001
|
Totally independent
|
9,658 (4,170–22,370)
|
< 0.001
|
Current smoker
|
0.851 (0.641–1,129)
|
0.264
|
Diabetes mellitus
|
1,128 (0.881–1,444)
|
0.339
|
Pulmonary disease
|
1,907 (1,295–2,808)
|
0.001
|
Cardiovascular disease
|
1,096 (0.882–1,361)
|
0.408
|
Chronic steroid therapy
|
1,649 (1,076–2,527)
|
0.022
|
Wound classification
|
|
|
Clean
|
Reference
|
–
|
Clean contaminated
|
1,413 (0.840–2,380)
|
0.193
|
Contaminated
|
2,545 (0.941–6,886)
|
0.066
|
Dirty/infected
|
3,677 (0.387–34,976)
|
0.257
|
Type of thyroidectomy
|
|
|
Partial
|
Reference
|
–
|
Total
|
0.964 (0.782–1,187)
|
0.727
|
Completion
|
1,185 (0.769–1,826)
|
0.441
|
Inpatient/outpatient status
|
|
|
Outpatient
|
Reference
|
–
|
Inpatient
|
1,507 (1,251–1,814)
|
< 0.001
|
Operative time/minutes
|
|
|
Less than 60
|
Reference
|
–
|
60–90
|
1,133 (0.816–1,574)
|
0.455
|
90–120
|
0.854 (0.599–1,217)
|
0.382
|
120–150
|
1,114 (0.770–1,612)
|
0.565
|
> 150
|
1,449 (1,027–2,044)
|
0.035
|
Abbreviations: ASA, American Society of Anesthesiologists; BMI, body mass index; OR, odds ratio.
Note: Only cases with complete data on all covariates were included (N = 177,847).
Complications
The UTI group was found to have significant associations with various postoperative
complications compared with the non-UTI group, including any complication, infectious
and non-infectious complications, sepsis, septic shock, pneumonia, unplanned reoperation,
CVA/stroke with neurological deficit, prolonged length of stay, mortality, and composites
of cardiac, vascular, and pulmonary complications ([Table 4]).
Table 4
Postoperative complications at 30-days, stratified by urinary tract infection status
Outcome
|
No UTI
N = 179,883
|
UTI
N = 490
|
p-value
|
Any complication
|
2,126 (1.2%)
|
79 (16.1%)
|
< 0.001
|
Non-infectious complication
|
1,015 (0.6%)
|
37 (7.6%)
|
< 0.001
|
CVA/stroke with neurological deficit
|
48 (0.0%)
|
3 (0.6%)
|
< 0.001
|
Cardiac complications
|
168 (0.1%)
|
3 (0.6%)
|
0.012
|
Myocardial infarction
|
95 (0.1%)
|
3 (0.6%)
|
0.003
|
Cardiac arrest requiring CPR
|
77 (0.0%)
|
0 (0.0%)
|
1.000
|
Pulmonary complications
|
674 (0.4%)
|
30 (6.1%)
|
< 0.001
|
Ventilator > 48 hours
|
254 (0.1%)
|
19 (3.9%)
|
< 0.001
|
Unplanned intubation
|
579 (0.3%)
|
23 (4.7%)
|
< 0.001
|
Renal complications
|
58 (0.0%)
|
1 (0.2%)
|
0.148
|
Progressive renal insufficiency
|
35 (0.0%)
|
0 (0.0%)
|
1.000
|
Acute renal failure
|
23 (0.0%)
|
1 (0.2%)
|
0.063
|
Vascular complications
|
203 (0.1%)
|
4 (0.8%)
|
0.003
|
Pulmonary embolism
|
109 (0.1%)
|
2 (0.4%)
|
0.037
|
DVT/thrombophlebitis
|
109 (0.1%)
|
2 (0.4%)
|
0.037
|
Infectious complications
|
1,285 (0.7%)
|
58 (11.8%)
|
< 0.001
|
Surgical site infection
|
848 (0.5%)
|
5 (1.0%)
|
0.085
|
Superficial
|
632 (0.4%)
|
3 (0.6%)
|
0.249
|
Deep
|
139 (0.1%)
|
1 (0.2%)
|
0.317
|
Organ/space
|
84 (0.0%)
|
1 (0.2%)
|
0.206
|
Sepsis
|
158 (0.1%)
|
43 (8.8%)
|
< 0.001
|
Septic shock
|
42 (0.0%)
|
6 (1.2%)
|
< 0.001
|
Wound disruption
|
72 (0.0%)
|
1 (0.2%)
|
0.180
|
Pneumonia
|
327 (0.2%)
|
12 (2.4%)
|
< 0.001
|
Unplanned reoperation
|
2,723 (1.5%)
|
24 (4.9%)
|
< 0.001
|
Prolonged length of stay
|
|
|
|
No
|
170,756 (95%)
|
406 (83.4%)
|
< 0.001
|
Yes
|
9,062 (5%)
|
81 (16.6%)
|
|
Missing
|
65
|
3
|
|
Mortality
|
97 (0.1%)
|
2 (0.4%)
|
0.030
|
Abbreviations: CPR, cardiopulmonary resuscitation; CVA, cerebrovascular accident; DVT, deep vein
thrombosis; UTI, urinary tract infection.
Note: Percentages are presented in columns.
After identifying the significant associations between UTIs and various complications,
an adjusted analysis was conducted. The results showed that the occurrence of UTIs
was strongly associated with any complication (OR: 12.298, 95% CI: 9.471–15.969),
acute renal failure (OR: 9.275, 95% CI: 1.223–70.337), and CVA/stroke with neurological
deficit (OR: 11.996, 95% CI: 3.652–39.401). In addition, the occurrence of UTIs was
also significantly associated with any pulmonary (OR: 10.281, 95% CI: 6.846–15.440),
vascular (OR: 3.702, 95% CI: 1.169–11.724), and cardiac complication (OR: 3.476, 95%
CI: 1.094–11.045). Infectious complications (OR: 15.561, 95% CI: 11.617–20.844), sepsis
(OR: 84.598, 95% CI: 57.738–123.954), septic shock (OR: 32.902, 95% CI: 13.531–80.006),
and pneumonia (OR: 8.616, 95% CI: 4.725–15.714) were also significantly associated
with postoperative UTIs. Finally, UTIs were found to be associated with prolonged
length of stay (OR: 2.914, 95% CI: 2.202–3.855) and unplanned reoperation (OR: 2.818,
95% CI: 1.856–4.279) as well ([Table 5]).
Table 5
Multivariable logistic regression analyses for different 30-day postoperative complications
with urinary tract infection as the main explanatory covariate
Outcome
|
Adjusted OR
|
p-value
|
Any complication
|
12,298 [9,471–15,969]
|
< 0.001
|
Non-infectious complications
|
8,601 [5,944–12,445]
|
< 0.001
|
CVA/stroke with neurological deficit
|
11,996 [3,652–39,401]
|
< 0.001
|
Cardiac complication
|
3,476 [1,094–11,045]
|
0.035
|
Myocardial Infarction
|
6,569 [2,052–21,025]
|
0.002
|
Cardiac arrest requiring CPR
|
Could not be computed
|
-
|
Pulmonary complication
|
10,281 [6,846–15,440]
|
< 0.001
|
Ventilator > 48 hours
|
14,841 [8,853–24,879]
|
< 0.001
|
Unplanned intubation
|
9,403 [6,014–14,701]
|
< 0.001
|
Renal complication
|
3,537 [0.483–25,914]
|
0.214
|
Progressive renal insufficiency
|
Could not be computed
|
-
|
Acute renal failure
|
9,275 [1,223–70,337]
|
0.031
|
Vascular complication
|
3,702 [1,169–11,724]
|
0.026
|
Pulmonary embolism
|
2,344 [0.324–16,946]
|
0.399
|
DVT/thrombophlebitis
|
4,424 [1,076–18,190]
|
0.039
|
Infectious complications
|
15,561 [11,617–20,844]
|
< 0.001
|
Surgical site infection
|
2,001 [0.824–4,859]
|
0.125
|
Superficial
|
1,667 [0.533–5,213]
|
0.380
|
Deep
|
2,182 [0.302–15,766]
|
0.439
|
Organ/space
|
3,943 [0.542–28,653]
|
0.175
|
Sepsis
|
84,598 [57,738–123,954]
|
< 0.001
|
Septic shock
|
32,902 [13,531–80,006]
|
< 0.001
|
Wound disruption
|
3,850 [0.524–28,265]
|
0.185
|
Pneumonia
|
8,616 [4,725–15,714]
|
< 0.001
|
Unplanned reoperation
|
2,818 [1,856–4,279]
|
< 0.001
|
Prolonged length of stay
|
2,914 [2,202–3,855]
|
< 0.001
|
Mortality
|
3,407 [0.820–14,149]
|
0.092
|
Abbreviations: CVA, cerebrovascular accident; DVT, deep vein thrombosis; OR, odds ratio.
Notes: No urinary tract infection was the reference group.
Regression adjusted for age, gender, body mass index, American Society of Anesthesiologists
physical status, wound class, operation time, indication, type of thyroidectomy, and
inpatient/outpatient surgery.
Only cases with complete data on all covariates and outcomes were included (N = 178,589).
Discussion
To provide a comprehensive understanding of UTIs among thyroidectomy patients, our
study investigated the risk factors and outcomes. Our findings identified several
significant risk factors, including age > 60 years, female gender, ASA classification
3 to 5, partially or totally dependent functional health status, pulmonary disease,
steroid therapy, inpatient procedure, and an operative time > 150 minutes. Notably,
our analysis also revealed that the development of UTIs was associated with an increased
likelihood of experiencing various complications, such as pulmonary, vascular, or
cardiac complication, stroke, acute renal failure, infectious complications, sepsis,
septic shock, pneumonia, prolonged length of stay, unplanned reoperation, and mortality.
These results underscore the importance of understanding the risk factors associated
with UTIs in this patient population and implementing effective control measures to
minimize the occurrence of complications.
Our study found advancing age and female gender to be significant demographic risk
factors for UTIs following thyroidectomy. These results are consistent with the well-established
association between female gender and UTI risk, as adult women are known to be 30
times more likely to develop UTIs than adult males below 50 years of age.[8] It is worth noting that a previous retrospective analysis reported no difference
in UTI rates between young, elderly, and supra-elderly age groups following thyroidectomy.[9] However, the prior study did not perform regression analysis specifically for the
development of UTIs and reported only univariate differences, which may explain the
disparity in results.
Our analysis revealed several surgical risk factors associated with the development
of UTIs following thyroidectomy, including ASA classification 3 to 5, inpatient procedure,
and an operative time > 150 minutes. The association between ASA class and postoperative
morbidity and mortality has been previously validated.[10] Although a recent study reported an association between dependent status and morbidity
following thyroidectomy, it did not specifically analyze the regression model for
UTIs, instead using a composite outcome that included UTIs along with other complications.[11] Furthermore, inpatient total thyroidectomies are well-known to be associated with
a significantly increased risk of UTIs, which could be due to the higher baseline
risk of more complex cases considered for inpatient surgery.[2] Another possible explanation is the faster and more frequent diagnosis of UTIs in
the inpatient setting. Similarly, a longer operative time is a known independent risk
factor for morbidity following multiple surgical procedures.[12] Taken together, our findings provide insight into the surgical risk factors associated
with UTIs following thyroidectomy and can inform targeted interventions to reduce
the incidence of this complication.
The importance of UTIs as a target for quality improvement initiatives is highlighted
by the Centers for Medicare & Medicaid Services (CMS) and Joint Commission.[13] Our findings have clinical relevance as they demonstrate that UTIs are linked to
several postoperative complications and mortality. This is consistent with a previous
study that found UTIs to be associated with increased risk of postoperative complications
and longer hospital stay in patients undergoing head and neck cancer surgery.[14] The inflammatory process that often accompanies UTIs can lead to urosepsis, a condition
that carries a high risk of mortality. Additionally, acute kidney injury resulting
from UTIs can lead to septic shock.[15] Notably, UTIs have been associated with up to a 3-fold increase in mortality among
patients undergoing colorectal cancer surgery.[16] Despite thyroidectomy being a comparatively simple procedure, the risks of morbidity
and mortality following UTIs are concerning.
The current study has several implications. First, our findings highlight the need
for a better understanding of modifiable risk factors to prevent the development of
UTIs and subsequent morbidity. It is crucial to optimize comorbid diseases associated
with UTIs preoperatively. Additionally, further investigation is needed to evaluate
and implement surgical techniques and equipment that can shorten operative time. As
our results indicate that UTIs increase the risk of postoperative complications, patients
who are catheterized or susceptible to UTIs should be counseled to remain vigilant
for any signs of developing a UTI. However, the impact of catheterization on the development
of UTIs could not be explored in this study, as it is not captured in the ACS-NSQIP.
Lastly, following the development of UTIs among thyroidectomy patients, it is imperative
to provide optimized care to prevent or adequately manage associated complications
and improve patient outcomes.
One major strength of our study is the analysis of a large and diverse sample of thyroidectomy
patients from a multi-institutional database, which enhances the generalizability
of our findings. However, our study has several limitations that must be acknowledged.
Notably, the ACS-NSQIP database lacks information on catheterization and its duration,
a known risk factor for UTI development in the inpatient setting.[17] Additionally, we could not differentiate the risk of UTIs based on the method of
diagnosis due to the lack of relevant data in the ACS-NSQIP. Our results are limited
to the 30-day postoperative period, and we cannot make conclusions beyond this time
frame. We also acknowledge the possibility of errors in the database as well as the
inherent limitations of retrospective studies, which only allow for the establishment
of associations rather than causation. Despite these limitations, our study provides
valuable insights into the association between UTIs and postoperative complications
following thyroidectomy.
Conclusion
Although UTIs may be rare among patients undergoing thyroidectomy, they carry a significant
morbidity and mortality burden for this cohort. This study has identified the risk
factors and outcomes of UTIs among thyroidectomy patients and recommends preoperative
optimization of comorbid diseases and reducing operative times as potential measures
to mitigate the risk of UTIs. Overall, this study highlights the importance of addressing
and managing UTIs in the context of thyroidectomy, which can potentially improve patient
outcomes and reduce the burden of postoperative complications.
Bibliographical Record
Usama Waqar, Warda Ahmed, Zoha Zahid Fazal, Ahmad Areeb Chaudhry, Haissan Iftikhar,
Afsheen Ziauddin, Syed Akbar Abbas. Incidence, Risk Factors and Outcomes of Urinary
Tract Infections among Patients Undergoing Thyroidectomy: Insights from the ACS-NSQIP.
Int Arch Otorhinolaryngol 2025; 29: s00441788769.
DOI: 10.1055/s-0044-1788769