Thyroid surgery and obesity: Cohort study of surgical outcomes and local specific complications

Clinical Impact of Obesity on Postoperative Outcomes of Patients With Thyroid Cancer Undergoing Thyroidectomy: A 5-Year Retrospective Analysis From the US National Inpatient Sample

BACKGROUND

The clinical impact of obesity on postoperative outcomes of patients undergoing thyroidectomy remains controversial.

METHODS

Patients aged ≥ 18 years who were diagnosed with thyroid malignancy and underwent thyroidectomy between 2016 and 2020 were included, and divided into two groups: patients with body mass index (BMI) < 30 kg/m2 and those with BMI ≥ 30 kg/m2. Patients in the obese group were then subdivided into four groups: Group 1 (BMI 30.0-34.9 kg/m2), Group 2 (BMI 35.0-39.9 kg/m2), Group 3 (BMI 40.0-44.9 kg/m2), and Group 4 (BMI ≥ 45.0 kg/m2) to evaluate the association between degree of obesity and clinical outcomes. We performed propensity score matching, compared outcome variables between the groups, and conducted adjusted multivariate logistic regression analyses of postoperative outcomes.

RESULTS

A total of 6778 patients diagnosed with thyroid cancer who underwent thyroidectomy were screened, of whom 1299 (19.2%) patients were obese. Patients in the obese group had higher total hospital charges (p < 0.001) and an increased risk of overall postoperative complications (34.7% vs. 30.5%, p = 0.023). Specifically, patients in the obese group had increased odds of respiratory complication (adjusted odds ratio (aOR) 1.66, 95% confidence interval (CI) [1.26-2.19]), acute renal failure (aOR 1.87, 95% CI [1.13-3.09]), and wound complication (aOR 2.77, 95% CI [1.21-6.37]) than those in the non-obese group. Moreover, trend tests showed that the risks of unfavorable discharge, infection, acute renal failure, and respiratory complication all exhibited an upward trend with increased BMI.

CONCLUSION

Obesity is associated with an increased risk of postoperative complications in patients with thyroid cancer undergoing thyroidectomy. This finding suggests that obese patients should be treated with more caution during postoperative recovery.

The impact of body mass index on operative time in transoral endoscopic thyroidectomy vestibular approach for thyroid cancer

BACKGROUND

The impact of body mass index (BMI) on operative time in transoral endoscopic thyroidectomy vestibular approach (TOETVA) for thyroid cancer is still a subject of debate. This study assessed the impact of BMI on operative time and postoperative complications in patients undergoing TOETVA.

METHODS

The study has been conducted to compare the outcomes of TOETVA in patients with high BMI (≥25) and those with normal BMI (<25). Postoperative outcomes, including operative time, blood lost, recurrent laryngeal nerve (RLN) palsy, hypocalcemia and postoperative pain score, were evaluated.

RESULTS

A total of 62 patients who underwent TOETVA were included in the study. The high BMI group consisted of 39 patients, while the normal BMI group included 23 patients. No significant differences were observed between the two groups regarding operative time, blood loss, postoperative pain score, and postoperative complications such as recurrent laryngeal nerve (RLN) palsy and hypocalcemia.

CONCLUSIONS

BMI was not significantly associated with operative time and postoperative complications in patients undergoing TOETVA, indicating its safety and feasibility for elevated BMI patients.

Thyroidectomy Outcomes in Obese Patients

INTRODUCTION

Obese patients often have higher complication rates after elective general surgeries; however, few studies have examined the outcomes after thyroidectomy. This study examines whether increased body mass index (BMI) is associated with poor postoperative outcomes after thyroid surgery.

METHODS

A retrospective review of patients who underwent thyroidectomy from 2015 to 2018 was performed. Demographics, comorbidities, pathology, and extent of resection (total versus hemithyroidectomy) were examined. Patients were classified into BMI groups according to the WHO definitions, and the incidence of surgical outcomes was determined in each group. Surgical outcomes of interest included readmission rates (RRs), length of stay, average operating room time, return to the operating room, hypocalcemia, postop infections, hematomas, and recurrent laryngeal nerve injury. Between-subjects statistics including independent samples t-test, ANOVA, and chi-square analyses were performed.

RESULTS

There were n = 465 patients included with a mean BMI 32.35 (standard deviation = 8.55) and median BMI 30.78 (Q1 = 26.26, Q3 = 36.73). There were no differences between BMI groups in age, gender, smoking, heart disease. There was a positive association between increased BMI and postoperative infection (P < 0.001), pneumonia (P = 0.018), and surgical site infection (P = 0.04), which were highest for BMI > 40. Increased BMI was associated with a higher 30-d RR (P = 0.008), particularly for BMI >40 versus BMI <40 (6.2% versus 1.05%; P = 0.003). There were no significant differences between surgical outcomes for patients with increased BMI who underwent total thyroidectomy or hemithyroidectomy.

CONCLUSIONS

Excellent postoperative outcomes were observed in all BMI categories. Higher postoperative infection and 30-d RRs were observed in the morbidly obese. Contrary to previous studies, operating room times were similar regardless of BMI.

The impact of obesity on thyroidectomy outcomes: a case-matched study

Obesity is a well-known public health concern in Western World. Accordingly, an elevated number of obese patients undergo thyroidectomy every year. We aim to assess the impact of obesity on intraoperative and postoperative outcomes of patients who undergo thyroidectomy. 1228 patients underwent thyroidectomy at our department between January 2021 and September 2021. We divided patients into two groups according to body mass index (BMI): non-obese (BMI < 30 kg/m2) and obese (BMI ≥ 30 kg/m2). A propensity score approach was performed to create 1:1 matched pairs (matching according to age, gender, diagnosis, nodule size and type of operation). After matching, the final population included 522 patients, equally divided between each group: non-obese group (Group A; n = 261) and obese group (Group B; n = 261). The primary endpoint of the study was the overall rate of postoperative complications; secondary endpoints of the study were operative time, use of energy device and length of hospital stay. The duration of hospital stay resulted longer in Group B (p = 0.002). No statistically significant differences were documented in terms of operative time (p = 0.206), use of energy devices (p = 0.855) and surgical complications (p = 0.429). Moreover, no statistically significant differences were documented considering each specific complication: transient and permanent hypocalcemia (p = 0.336; p = 0.813, respectively), transient and permanent recurrent laryngeal nerve palsy (p = 0.483; p = 0.523, respectively), hematoma (p = 0.779), bleeding (p = 0.178), wound infection (p = 0.313) and cheloid formation (p = 0.412). Thyroidectomy can safely be performed in obese patients. Outcomes resulted comparable; nonetheless, obesity correlates to longer hospital stay.

Accurate Operative Time Prediction in Thyroid Surgery: A Rural Tertiary Care Facility Experience

OBJECTIVE

To determine whether surgeons can estimate thyroid operative time more accurately than a system-generated average time estimate.

METHODS

Four otolaryngologists at a single institution with extensive endocrine surgery experience were asked to predict their operative times for all eligible thyroid surgeries. These estimates were compared to system-generated operative time predications based on averaging the surgeon's previous 10 cases with the same Current Procedural Terminology code. The surgeon-generated estimations and system-generated estimations were then compared to each other and the actual operative time.

RESULTS

A final sample of 73 cases was used for all analyses. Average age was 51 years old and the majority of patients were female. Surgeon-generated operative time estimates were significantly more accurate than system-generated estimates based on time averaging (P < .001). These findings were consistent across each surgeon individually and within each procedure type (hemithyroidectomy and total thyroidectomy). These findings had a power of over 99% based on mean differences.

CONCLUSION

As the financial center of modern hospitals, an efficient operating room is integral to economic success. Improving the precision of operative time estimation reduces costly unplanned staff overtime, canceled cases, and underutilization. Our research at a rural tertiary care center shows that experienced thyroid surgeons can substantially reduce the error of estimating thyroid operative times by considering individual patient characteristics. Although no objective variables have so far been identified to correlate with thyroid operative time, surgeon-generated operative time estimation is significantly more accurate than a generic system approach of averaging previous operative times.

Transient Hypocalcemia After Total Thyroidectomy: The Obesity Paradox at Work?

INTRODUCTION

With increasing rates of obesity worldwide, a correlation between high body mass index (BMI) and postoperative morbidity after thyroid surgery remains unclear. Postoperative transient hypocalcemia is common after total thyroidectomy due to interruption of parathyroid function. This study examines the relationship between BMI and hypocalcemia after total thyroidectomy.

MATERIALS AND METHODS

A retrospective review of prospectively collected data for 1135 patients who underwent total thyroidectomy for cancer, multinodular goiter (MNG), or Graves' disease between June 2009 and November 2020 at a single institution was performed. BMI groups followed the World Health Organization classification. Hypocalcemia was defined as serum calcium ≤8 mg/dL. Calcium levels measured on postoperative day 0 and the following morning were compared between the BMI groups.

RESULTS

Of 1135 total thyroidectomy patients, 85% were women. The mean age and standard deviation of patients was 49 (± 13) y, with most of Hispanic origin (64%). Overall, 41.5% of patients had cancer, 45% nontoxic MNG, 5.8% toxic MNG, and 12% Graves' disease. Stratified by BMI, 27% of patients were normal, 34% overweight, and 39% obese. Overall, overweight and obese patients experienced less transient hypocalcemia at both time points compared to normal patients postoperatively (P = 0.01 and P = 0.009). Furthermore, overweight and obese patients with Graves' disease experienced less transient hypocalcemia at both time points (P = 0.04 and P = 0.05). There was no statistical difference in other groups.

CONCLUSIONS

A protective role of higher BMI or "obesity paradox" for postoperative hypocalcemia may exist in those obese patients after total thyroidectomy.

Obesity as a Risk Factor for Postoperative Adverse Events in Skull Base Surgery

OBJECTIVE

To determine the implications of obesity on postoperative adverse events following skull base surgery.

METHODS

The 2005-2017 American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was queried for adverse events in skull base surgery cases. Patients were stratified by body mass index (BMI) into normal weight (18.5 ≤ BMI < 25), overweight (25 ≤ BMI < 30), and obese (BMI ≥ 30) cohorts. Logistic regression was used to assess the association of overweight or obese BMI with various 30-day postoperative adverse events.

RESULTS

A total of 2305 patients were included for analysis, of which 732 (31.8%) and 935 (40.6%) were overweight or obese, respectively. The mean age was 53.8 ± 15.3 years and 1214 (52.7%) patients were female. Obese patients were younger (P = .033) and possessed higher frailty (P < .001) and ASA scores (P < .001). Operation times and lengths of hospitalization were not significantly different across patient cohorts (all P > .05). On propensity score-adjusted multivariable analysis, only bleeding (OR = 0.42, P < .001) and deep vein thrombosis (OR = 6.46, P = .015) were significantly associated with obesity. There were no significant differences in rates of readmission, reoperation, or mortality between normal weight and obese patients (all P > .05).

CONCLUSIONS

Obesity was associated with decreased postoperative bleeding and increased deep vein thromboses. Obese patients were otherwise at no higher risk for medical or surgical complications. Elevated BMI did not confer an increased risk for readmission, reoperation, or death. Thus, patient obesity should not be a major determinant in offering skull base surgery in individuals who would otherwise benefit from treatment.

Association of BMI with Clinicopathological Features of Papillary Thyroid Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

Papillary thyroid cancer (PTC) is the most common subtype of thyroid cancer. The incidence of PTC is rising in tandem with an obesity epidemic. Associations have been demonstrated between increased body mass index (BMI) and worse oncological outcomes in a number of malignancies. However, research on this topic in PTC to date has been inconsistent, often due to limited data. This study aimed to measure the association between BMI and potentially adverse clinicopathological features of PTC.

METHODS

A meta-analysis of studies reporting outcomes after surgical treatment of PTC was performed. PubMed, Embase and the Cochrane Library were searched systematically to identify studies which provided data on BMI and clinicopathologic features of PTC. Relevant data were extracted and synthesis performed using adjusted odds ratios where available and crude values when not. Data were analysed by inverse variance using random and fixed effects models.

RESULTS

Data on 35,237 patients from 15 studies met the criteria for inclusion. Obesity was associated with larger tumour size (MD = 0.17 cm [0.05, 0.29]), increased rates of multifocality (OR = 1.41 [1.16, 1.70]), extrathyroidal extension (OR = 1.70 [1.39, 2.07]) and nodal spread (OR = 1.18 [1.07, 1.30]). Associations were more pronounced as BMI increased. There was no association between BMI and bilaterality, vascular invasion or metastatic spread.

CONCLUSION

Increased BMI is significantly associated with multiple potentially adverse features of PTC. The effect on long-term oncological outcomes requires further evaluation.

Hyperthyroidism Symptoms, Management, and Outcomes in Children and Adults Seeking Definitive Surgical Treatment

OBJECTIVE

To identify the difference in presentation, time to treatment, and outcomes between hyperthyroid adults and children referred to surgical evaluation.

BACKGROUND

There is little data on differences in presenting symptoms, time to treatment, and outcomes between adults and children presenting for thyroidectomy for Graves' disease.

METHODS

We retrospectively reviewed records of patients with hyperthyroidism referred for thyroidectomy between January 2016 and April 2017. We divided our cohort into 2 groups based on age, children (age ≤18 years), and adults (age >18), and evaluated the difference in prevalence of symptoms, time from diagnosis, and initiation of antithyroid medications to surgery, and outcomes.

RESULTS

We identified 38 patients (27 adults and 11 children) with data on hyperthyroidism symptoms referred for thyroidectomy. Relative to hyperthyroid adults, children with hyperthyroidism were more likely to present with hoarseness (55% vs 15%, P = 0.01) and difficulty concentrating (45% vs 7%, P = 0.01) at initial presentation. There was no statistically significant difference in prevalence of vision changes, exophthalmos, pretibial myxedema, palpitations, fatigue, temperature intolerance, dysphagia, tremors, or constitutional symptoms. A median of 15 months elapsed from diagnosis to thyroidectomy among adult and 6 months among pediatric patients. Adult and pediatric patients waited a median of 13 and 6 months from initiation of antithyroid medications to thyroidectomy, respectively. There was no significant difference in outcomes.

CONCLUSIONS

Children with hyperthyroidism were more likely to present with hoarseness and difficulty concentrating than adults. Concentration and communication are critical skills in developing children, and early intervention with definitive therapy may improve such symptoms.

Central neck dissection is an independent risk factor for incidental parathyroidectomy

OBJECTIVE

This study aims to determine the frequency of incidental parathyroidectomy (IP), to reveal the risk factors and to present the clinical importance of IP through the experiences of our clinic.

MATERIALS AND METHODS

Patients undergoing thyroid surgery between June 2016 and May 2019 were reviewed retrospectively. Along with demographic data, surgery reports, pathology results and postoperative follow-up data were examined. Factors assumed to be associated with IP and postoperative hypocalcemia were compared between the IP group and the non-IP group.

RESULTS

A total of 633 patients with a mean age of 48 ± 13 years were included in this study. IP was detected in 138 (21.8%) patients and parathyroid glands were localized 29.72% intrathyroidal. Postoperative hypocalcemia in the IP group was approximately 2-fold higher than the no-IP group (%15.94 to %7.27), (p < .001). Gender (p = .014), body mass index (p = .021), both preoperative and postoperative diagnosis of malignancy (p < .001) and performing central neck dissection (CND) (p < .001) were significantly associated with IP in univariate analysis. However, multivariate analysis demonstrated that CND was independently associated with IP (OR = 0.301, 95% Cl: 0.161-0.562, p < .001).

CONCLUSION

This study reveals that IP increases the frequency of postoperative temporary and permanent hypocalcemia in patients undergoing thyroid surgery, and CND is the only independent risk factor for IP. Highlights of the study This study reveals that central neck dissection is the most important and only independent risk factor for incidental parathyroidectomy in patients undergoing thyroid surgery. According to our analysis, both temporary and permanent hypocalcemia, which occurs in the postoperative period, are associated with incidental parathyroidectomy.

A Cohort Study Assessing the Association Between Body Composition Parameters and Symptomatic Hypocalcemia After Total Thyroidectomy

BACKGROUND

Postoperative hypocalcemia is one of the major concerns following thyroidectomy and the most frequent cause of prolonged hospital stay. The aim of this study was to evaluate the relationship between body composition parameters and symptomatic hypocalcemia following total thyroidectomy. In addition, the effects of disease- and patient-related factors on hypocalcemia were investigated.

METHODS

A total of 144 patients were prospectively included between March 2014 and September 2017. Patients were divided into 2 groups according to the presence or absence of clinical symptoms of hypocalcemia. Subsequently, the relationship between body composition parameters and hypocalcemia was evaluated.

RESULTS

Postoperative hypocalcemia-related symptoms occurred in 28 patients (19.4%). Permanent hypocalcemia was not encountered in any patient. Patients with hypocalcemic symptoms were more likely to have nodules ≥40 mm (39.3% vs. 17.2%, P = .011), retrosternal goiters (25.0% vs. 7.8%, P = .017), central lymph node dissection (LND) (32.1% vs. 11.2%, P = .015), and parathyroid autotransplantation (28.6% vs. 3.4%, P < .001) than those without symptoms. However, no differences were observed in the body composition parameters between symptomatic and asymptomatic patients. On multivariate analysis, lower preoperative intact parathyroid hormone (iPTH) levels (odds ratios (ORs) .96, 95% confidence intervals (CIs) .93-.99), the presence of retrosternal goiters (OR 10.26, 95% CI 2.23-47.14), central LND (OR 16.05, 95% CI 3.90-66.07), and parathyroid autotransplantation (OR 36.22, 95% CI 6.76-194.13) predicted hypocalcemia.

DISCUSSION

This study demonstrates that patients with lower preoperative iPTH levels, retrosternal goiters, central LND, and parathyroid autotransplantation are at an increased risk of developing clinical symptoms of hypocalcemia. Body composition parameters have no effect on the incidence of hypocalcemia after total thyroidectomy.

Can thyroidectomy be considered safe in obese patients? A retrospective cohort study

BACKGROUND

Obesity is a growing public health concern in most western countries. More and more patients with high body mass index (BMI) are undergoing surgical procedures of all kinds and, in this context, obese patients are undergoing thyroid surgery more than ever before. The aim of the present study was to evaluate whether thyroidectomy can be considered safe in obese patients.

METHODS

Patients undergoing thyroidectomy in our Unit between January 2014 and December 2018 were retrospectively analysed. Patients were divided into two groups: those with BMI < 30 kg/m² were included in Group A, while those with BMI ≥ 30 kg/m² in Group B. Univariate analysis was performed to compare these two groups. Moreover, multivariate analyses were performed to evaluate whether the BMI value (considered in this case as a continuous variable) had a significant role in the development of each individual postoperative complication.

RESULTS

A total of 813 patients were included in this study: 31 (3.81%) were underweight, 361 (44.40%) normal-weight, 286 (35.18%) overweight, 94 (11.57%) obese and 41 (5.04%) morbidly obese. Six hundred and seventy-eight patients were included in Group A and 135 in Group B. At univariate analysis, the comparison between the two groups, in terms of operative time and thyroid weight resulted in statistically significant results (P = 0.001, P = 0.008; respectively). These features were significantly higher in Group B than in Group A. About postoperative stay and complications, no statistically significant difference was found between the two groups. At multivariate analyses, only the development of cervical haematoma was statistically significantly correlated to the BMI value. Patients with high BMI had a lower risk of cervical haematoma (P = 0.045, OR 0.797, 95% CI 0.638-0.995).

CONCLUSIONS

This study showed that obesity, in the field of thyroid surgery, is not associated with any increase of postoperative complications. Thus, it is possible to conclude that thyroidectomy can be performed safely in obese patients. Our result about operative times had no clinical significance.

The relationship between thyroidectomy complications and body mass index

INTRODUCTION

Obesity is a growing public health problem associated with many comorbid diseases. The aim of this study was to evaluate the relationship between body mass index and complications of thyroidectomy.

METHODS

Patients who underwent total thyroidectomy between January 2015 and December 2018 were enrolled. Patients were divided into two groups, i.e., BMI <25 (group A) and BMI≥ 25 (group B). Demographics, operative time, and complications were retrospectively reviewed.

RESULTS

The study included 145 patients (66 in Group A and 79 in Group B). There was no significant difference between the two groups in terms of age (p=0.330) and gender (p=0.055). No surgical site infection and bleeding complications were observed in any patients. The mean operative time was 148.4 minutes (90-235) in Group A and 153.4 minutes (85-285) in Group B (p=0.399). Transient hypocalcemia was observed in 25 (37.9%) patients in group A, and 23 (29.1%) patients in Group B (p = 0.291). Permanent hypocalcemia was not observed in any patient in group A, and in 2 patients in Group B (2.5%) (p = 0.501). Transient recurrent nerve palsy was observed in 1 (1.5%) patient in Group A and in 3 (3.8%) patients in Group B (p=0.626). None of the patients had permanent recurrent nerve palsy. Parathyroid autotransplantation was performed on 1 patient (1.5%) in group A and on 7 (8.9%) patients in Group B (p=0.055).

CONCLUSION

We think there is no relationship between a high BMI and thyroidectomy complications, and surgery can also be performed safely in this patient group.

Influence of Body Mass Index on Survival and Prognosis in Squamous Cell Carcinoma of Head and Neck

OBJECTIVE

Differences in body mass index (BMI) were used to analyze the survival and prognosis of SCCHN patients.

PATIENTS AND METHODS

A retrospective cohort study was conducted to select 323 patients who underwent surgical treatment for SCCHN from June 2013 to June 2016. The patients were divided into a healthy BMI group (BMI<24kg/m2), an overweight group (24kg/m2≤BMI<28kg/m2) and an obese group (BMI≥28 kg/m2). Various statistical methods were used to summarize and analyze clinical data, complications, disease specific survival (DSS), the overall survival (OS), and recurrence-free survival (RFS) within the last 3 y.

RESULTS

At 3 y, OS (54.40%) and DSS (51.94%) were slightly lower in the obese group compared with the overweight (64.62%, 61.92%) and healthy BMI groups (64.66%, 65.02%), but no statistical significance was found in DSS (P=0.178), OS (P=0.123) and RFS (P=0.362). The difference in operation duration (P=0.008) and bleeding volume (P=0.001) in obese patients was consistent with those in diabetes mellitus (P=0.002) and coronary heart disease (P=0.000). A high incidence of pharyngeal fistula was observed in obese (P=0.014) and overweight patients (P=0.025), but mouth floor fistula (P=0.038), lung infection (P=0.047), fat liquefaction (P=0.003) and lower extremities deep venous thrombosis (P=0.020) were only found in the obese group. Cox univariatable and multivariatable analysis showed that clinical stage, T stage, and N stage were independent prognostic factors for patients with SCCHN, which was not related to BMI.

CONCLUSION

BMI was associated with a higher probability of complications. However, BMI had no significant correlation with 3-year OS, RFS and DSS, and was not a prognostic indicator for patients with SCCHN.

Obesity May Not Affect Outcomes of Transoral Robotic Thyroidectomy: Subset Analysis of 304 Patients

OBJECTIVES/HYPOTHESIS

Obesity is an increasing health concern worldwide. It has been associated with perioperative complications that could affect patient outcomes. Our aim was to compare surgical outcomes in obese and nonobese patients after transoral robotic thyroid (TORT) surgery.

STUDY DESIGN

Retrospective cohort study.

METHODS

A total of 304 consecutive patients who underwent TORT between January 2012 to December 2017 were included in the study. Patients were divided into two groups according to their body mass index (BMI): BMI < 30 kg/m² and BMI ≥30 kg/m² . Patient demographics, operative extent, pathological data, surgical outcomes, and postoperative complications were included and analyzed. A χ² test was used to compare categorical variables, and a Student t test was used to compare changes of continuous variables between groups. Statistical significance was conferred by a two-tailed P value of ≤.05.

RESULTS

There were 290 patients in the non-obese group and 14 patients in the obese group. There was no statistically significant difference between the two groups in terms of patient demographics, operative procedure, or pathological characteristics. The only statistically significant difference was for lymph node dissection (P = .012); however, for both groups, unilateral central node dissection was the most common procedure. There was also no statistically significant difference found for operative time, length of stay, pain score, or postoperative complications including TORT-specific complications such as oral commissure tear and general complications such as recurrent nerve injury.

CONCLUSIONS

This initial experience shows that TORT appears to be a safe and feasible option for obese patients pursuing scarless thyroid surgery.

LEVEL OF EVIDENCE

NA Laryngoscope, 130:1343-1348, 2020.