Endocrine Abstracts

Introduction: Patients undergoing transsphenoidal pituitary surgery (TPS) may develop water balance disorders post-operatively, with diabetes insipidus (DI) being the most common. Nonetheless, data on the prevalence of post-operative DI are not consistent necessitating a systematic review of the literature.

Aim: To estimate the prevalence of DI following TPS in patients with pituitary adenomas (PAs), craniopharyngiomas and Rathke’s cleft cysts (RCCs) by performing a systematic review and meta-analysis of published studies which have provided clear criteria of DI diagnosis.

Methods: Extensive literature search of Medline, Embase and Cochrane Library between 01/01/2000 and 31/12/2020 was conducted. Prevalence of postoperative DI, effect size (ES) and 95% confidence intervals (CIs) were estimated from each study and pooled using random effects meta-analysis model.

Results: From a total of 11,627 studies, 54 were finally included. Overall, 22% of patients who underwent TPS developed post-operative DI (ES 0.22; 95%CI, 0.17-0.27). In particular, DI was diagnosed in 19% (ES 0.19; 95%CI, 0.15-0.23), 61% (ES 0.61; 95%CI, 0.49-0.72) and 44% (ES 0.44; 95%CI, 0.27-0.61) of patients with PAs, craniopharyngiomas and RCCs, respectively. Data specifically on rates of transient and permanent post-operative DI were provided in 40 studies; prevalence of transient and permanent DI in total population was 17% (ES 0.17; 95%CI, 0.13-0.21) and 3% (ES 0.03; 95%CI, 0.02-0.05), respectively. Further subgroup analyses revealed prevalence of post-operative transient and permanent DI of 16% (ES 0.16; 95%CI, 0.12-0.20) and 2% (ES 0.02; 95%CI, 0.02-0.03) in patients with PAs, 31% (ES 0.31; 95%CI, 0.24-0.39) and 30% (ES 0.30; 95%CI, 0.22-0.39) in patients with craniopharyngiomas, as well as 35% (ES 0.35; 95%CI, 0.16-0.57) and 14% (ES 0.14; 95%CI, 0.06-0.23) in patients RCCs, respectively. Prevalence of DI was also affected by the diagnostic criteria used in each study. When hypotonic polyuria was sole criterion of diagnosis, post-operative DI was reported in 18% of patients (ES 0.18; 95%CI, 0.12-0.26), whilst in studies where both hypotonic polyuria and hypernatraemia were required as diagnostic criteria, prevalence was 29% (ES 0.29; 95%CI, 0.18-0.42). In those studies where diagnosis was based on desmopressin administration requirement, 26% of cases developed post-operative DI (ES 0.26; 95%CI, 0.09-0.48).

Conclusions: Overall, 22% of patients undergoing TPS for the above tumours will develop post-operative DI. This resolves in the majority of PAs and remains permanent in a significant number of craniopharyngiomas and RCCs. Diagnostic criteria for post-operative DI remain variable affecting the reported prevalence of this condition.