Risk of hypothyroidism following hemithyroidectomy: systematic review and meta-analysis of prognostic studies.
ABSTRACT The reported risk of hypothyroidism after hemithyroidectomy shows considerable heterogeneity in literature.
The aim of this systematic review and meta-analysis was to determine the overall risk of hypothyroidism, both clinical and subclinical, after hemithyroidectomy. Furthermore, we aimed to identify risk factors for postoperative hypothyroidism.
A systematic literature search was performed using several databases, including PubMed.
Original articles in which an incidence or prevalence of hypothyroidism after primary hemithyroidectomy could be extracted were included.
Study identification and data extraction were performed independently by two reviewers. In case of disagreement, a third reviewer was consulted.
A total of 32 studies were included in this meta-analysis. Meta-analysis was performed using logistic regression with random effect at study level. The overall risk of hypothyroidism after hemithyroidectomy was 22% (95% confidence interval, 19-27). A clear distinction between clinical (supranormal TSH levels and subnormal thyroid hormone levels) and subclinical (supranormal TSH levels and thyroid hormone levels within the normal range) hypothyroidism was provided in four studies. These studies reported on an estimated risk of 12% for subclinical hypothyroidism and 4% for clinical hypothyroidism. Positive anti-thyroid peroxidase status is a relevant preoperative indicator of hypothyroidism after surgery. Effect estimates did not differ substantially between studies with lower risk of bias and studies with higher risk of bias.
This meta-analysis showed that approximately one in five patients will develop hypothyroidism after hemithyroidectomy, with clinical hypothyroidism in one of 25 operated patients.
- [Show abstract] [Hide abstract]
ABSTRACT: ABSTRACT Purpose: No previous study regarding the correlation between post-operative thyroid function and underlying thyroid histopathology has been published. This study assessed the relationship between postoperative thyroid function after lobectomy and multiple factors in papillary thyroid microcarcinoma (PTMC) patients. Materials and methods: From January 2010 to December 2010, 338 patients who had undergone thyroid lobectomy for PTMC were enrolled. Patients with pre-operative hyperthyroidism or those with hypothyroidism but no pre-operative serological data were excluded, leaving a cohort of 285 patients. The relationships between post-operative thyroid function (based on successful cessation of thyroxine replacement therapy) and multiple factors (patient age and sex, serological data, the Pre-operative anteroposterior diameter of the thyroid gland, underlying histopathology of the thyroid gland, and number of attempts to stop thyroxine replacement therapy) were analyzed. Results: Out of 285 patients, 157 attempted to stop thyroxine replacement therapy once or twice after lobectomy; 91 successfully stopped thyroxine replacement therapy during the study period. The final histopathologic diagnoses after surgery included Hashimoto's thyroiditis (n = 5), non-Hashimoto type of lymphocytic thyroiditis (n = 17), and normal thyroid parenchyma (n = 135). Pre-operative thyroid-stimulating hormone (TSH) levels differed significantly between patients with postoperative hypothyroidism and those with postoperative euthyroidism (univariate logistic regression analysis, p = 0.0028; multivariate logistic regression analysis, p = 0.0029). No statistically significant differences were found for any other factors. Conclusions: The study results demonstrated that the Pre-operative TSH level was the only predictor for the development of post-operative hypothyroidism after thyroid lobectomy in PTMC patients.Endocrine Research 08/2014; 40(1):1-5. · 1.41 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: Background Thyroid function, as assessed by thyroid stimulating hormone (TSH) levels, was evaluated in patients after thyroid lobectomy. These assessments were analyzed against perioperative measurements to determine if any of these preoperative values were predictive of postoperative hypothyroidism and the need for postoperative levothyroxine treatment. Methods In a retrospective study, data from 276 thyroid lobectomy patients were examined. These surgeries occurred over the period from January 2003 to December 2012. Age, sex, volume of resected thyroid, thyroiditis, preoperative free T4, TSH, and microsomal antibody levels were analyzed for correlation with postoperative levothyroxine supplementation. Results The overall percentage of the patients taking postoperative levothyroxine was 23.6%. The preoperative TSH level showed strong correlation with TSH levels measured one month postoperatively (p < 0.001). Preoperative TSH levels > 2.5 mIU/L and positive microsomal antibody showed significant correlation with postoperative levothyroxine supplementation (p < 0.001; relative risk, 8.933 and 3.438, respectively). By stratifying the patients based on preoperative TSH levels and presence of microsomal antibodies, in the low-risk group with TSH < 2.5 mIU/L and negative microsomal antibody, 7% of patients received postoperative levothyroxine replacement but in the high-risk group with TSH > 2.5 mIU/L and positive microsomal antibody, 77.8% required levothyroxine replacement (p < 0.001). Conclusions The most significant preoperative predictors for levothyroxine supplementation are preoperative TSH level and presence of microsomal antibodies. Patients with preoperative TSH lower than 2.5 mIU/L showed a low risk of requiring postoperative levothyroxine supplementation.Journal of Surgical Research 07/2014; · 2.12 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: Objectives Diagnostic and therapeutic processing of a thyroid nodule in children and adolescents may require lobectomy-isthmusectomy (LI) or nodule-resection (NR). Very few data in the literature report the long-term evolution of the remaining thyroid lobe in a defined pediatric population. In this study, we aimed to answer the following questions: Does a nodule recurrence occur in the remainder lobe? Is a post-operative thyroxine treatment necessary? Material and Methods This retrospective study describes 28 patients under 18 who underwent LI (22 cases) or NR (6 cases) from January 2004 to March 2012. Ten of them were lost to follow up, 18 could be assessed (4 NR (22%) and 14 LI (78%) - mean follow-up 45 ± 31 months). All patients benefited of post-operative thyroid ultrasonography, and regular endocrinologic follow-up. The following data were analysed: emergence of new thyroid nodules, evolution of pre-existing nodules, occurrence of post-operative hypothyroidism and requirement for completion thyroidectomy. Results The mean age at the time of surgery was 14.3 ± 1.9 years. Two patients (11%) had pre-existing nodules in the remaining thyroid gland, none of which showed an increase in size after surgery. De novo nodules developed in 5 patients (27.8%). Three patients who underwent LI (21.4%) needed thyroxine treatment for post-operative hypothyroidism. One patient (5.5%) needed completion thyroidectomy. Conclusions In this children and adolescents population, after performing LI or NR, remaining thyroid tissue stays free of nodules in 72.2% of the cases. A post-operative thyroxin treatment is necessary in 21.4% of cases after LI.International Journal of Pediatric Otorhinolaryngology 10/2014; · 1.32 Impact Factor