Abnormal plasma sodium concentrations in patients treated with desmopressin for cranial diabetes insipidus: results of a long-term retrospective study

Context and objectivePatients with cranial diabetes insipidus (CDI) are at risk of developing both hypernatraemia and hyponatraemia, due to the condition itself or secondary to treatment with vasopressin-analogues or during administration of i.v. fluids. We aimed to assess the frequency and impact of dysnatraemias in the inpatient (INPT) and outpatient (OPT) setting in desmopressin-treated CDI, comparing those with normal thirst with those with abnormal thirst.DesignThe study included 192 patients with cranial diabetes, who were identified from the Beaumont Pituitary Database, a tertiary referral centre. Retrospective case note audit was performed and the clinical and biochemical information of 147 patients with CDI were available for analysis.ResultsA total of 4142 plasma sodium measurements for 137 patients with normal thirst, and 385 plasma sodium measurements for ten patients with abnormal thirst were analysed. In those with normal thirst, the most common OPT abnormality was mild hyponatraemia (pNa+ 131–134 mmol/l) in 27%, while 14.6% had more significant hyponatraemia (pNa+ ≤130 mmol/l). Of those patients with normal thirst, 5.8% were admitted due to complications directly related to hyponatraemia. Compared with patients with normal thirst, those with abnormal thirst were more likely to develop significant OPT hypernatraemia (20% vs 1.4%, P=0.02) and significant INPT hyponatraemia (50% vs 11.1%, P 0.02).ConclusionOPT management of CDI is complicated by a significant incidence of hyponatraemia. In contrast, OPT hypernatraemia is almost exclusively a complication seen in adipsic CDI, who also had more frequent INPT hyponatraemia. CDI associated with thirst disorder requires increased physician attention and patient awareness of potential complications.

Systematic review of overactive bladder therapy in females

Although the prevalence of overactive bladder (OAB) is similarin both male and female populations, females have a greater tendencyto seek medical advice regarding their symptoms. A reviewof the evidence of therapy among women shows that a variety ofmodalities has been shown to be effective for symptom improvementin women with OAB. Bladder retraining/re-education shouldbe considered for all women with OAB. With respect to first-linepharmacotherapy with antimuscarinic agents, the development ofextended release preparations, bladder selective M3 antagonistsand alternative routes of delivery, have improved compliance andpersistence. Other pharmacotherapeutic options with potential forproviding benefit include antidepressants, vasopressin analogues,alpha-adrenoceptor antagonists and beta-adrenoceptor agonists.There are also a number of newer agents currently being investigated,including calcium channel blocking agents, potassium channelopening drugs, beta agonists and neurokinin receptor antagonists.Intravesical injections of botulinum toxin may be an alternative,while surgery can be considered for truly intractable cases.