Effects of methylphenidate on the lower urinary tract in patients with attention deficit hyperactivity disorder and
Mahmut Taha Ölçücü1, Hilal Tuğba Kiliç2, Kadir Yildirim3
1Agri State Hospital, Department of Urology, Agri, Turkey; University of Health Sciences, Antalya Training and Research Hospital, Department of Urology, Antalya, Turkey.
Background:
Attention deficit hyperactivity disorder (ADHD) is characterised by a range of symptoms, such as excessive mobility, difficulty in maintaining attention and inadequate impulse control. Methylphenidate (MPH) is widely prescribed as a treatment for ADHD. In the literature, studies investigating the effects of MPH on the lower urinary tract (LUT) are limited.
Objective:
The aim of the study was to evaluate MPH-induced LUT symptoms (LUTSs) in patients with ADHD without a diagnosis of voiding dysfunction (VD).
Study Design:
After ethical committee approval, volunteers aged 7-17 y were divided into two groups, with group 1 composed of individuals diagnosed with ADHD but not VD and group 2 (control) composed of healthy individuals. Lower urinary tract symptoms and quality of life, in addition to uroflowmetry test results and postvoiding residual volume (PVRV), were evaluated in both groups at baseline and again 4 wk later. The individuals in group 1 were treated with MPH after baseline screening. The dysfunctional voiding scoring system questionnaire was used for scoring LUTSs. Postvoiding residual volume was measured by ultrasound. Bladder capacity (BC) was calculated as the sum of voided volume (VV) and PVRV. The means of the maximum flow rate (Q max), mean flow rate (Q mean), VV, PVRV and BC were recorded.
Results:
After exclusions, there were 43 participants in group 1 and 39 participants in group 2. There was no significant difference between the mean age of groups (p = 0.727). Compared with the baseline, VV and BC increased significantly in group 1 (p = 0.001 and p = 0.002, respectively) at the 4-wk follow-up. There was no significant difference in these parameters in group 2.
Discussion:
This study demonstrated that VV and BC increased after MPH treatment in patients with ADHD without a diagnosis of VD. The mechanism underlying this effect is unclear, but it may be associated with dopaminergic and noradrenergic effects.
Conclusion:
The findings of the present study can inform further studies on the mechanism underlying the effect of MPH on the LUT. In a future study, the authors suggest evaluating the effects of MPH in a urodynamic study in patients with ADHD diagnosed with VD.
Related Concept Videos
01:30Attention-Deficit/Hyperactivity Disorder
Diagnostic Criteria and Symptoms
To diagnose ADHD, symptoms must manifest before age 12 and be evident across multiple settings....
01:26The Micturition Reflex
The process begins with bladder filling, where the bladder wall stretches as urine accumulates. This stretching activates the urine storage reflex, mediated by the sacral spinal segments and the pontine storage center. Efferent sympathetic impulses stimulate the detrusor muscle to relax and the internal urethral sphincter to contract, facilitating...
01:28Adrenergic Agonists: Mixed-Action Agents
Ephedrine and pseudoephedrine lack a catecholamine group, making them less susceptible to degradation by metabolic enzymes. They have increased oral bioavailability and lipophilicity, resulting in a longer duration of action. Their response is reduced by...
01:24Antiasthma Drugs: Methylxanthines
Theophylline is thought to inhibit phosphodiesterase enzymes, increasing intracellular levels of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP). This rise in cAMP and cGMP concentrations stimulates cardiac function,...
01:19Urodynamic Studies: Uroflowmetry
01:28Cholinergic Antagonists: Pharmacological Actions
Gastrointestinal Effects: Antimuscarinics reduce gut contractions, increase gastric emptying, and slow intestinal transit. They partly inhibit gastric acid secretion...