Tolterodine can reduce storage symptoms in men treated with alpha-blockers for lower urinary tract symptoms suggestive of overactive bladder (OAB), a trial has shown.

A total of 652 men, aged 40 years or older, with persistent frequency and urgency despite being on a stable dose of an alpha-blocker for at least a month were studied. They were randomised to receive either tolterodine ER 4mg once daily or placebo for 12 weeks, while continuing their alpha-blocker therapy.

Using the Patient Perception of Bladder Condition questionnaire similar improvement was reported in the two groups, 63.6% on tolterodine and 61.6% on placebo. However, significant reductions in bladder diary end points were seen in the tolterodine group compared with the placebo group for: number of 24-hour (-1.8 vs -1.2; p=0.0079) and daytime (-1.3 vs -0.8; p=0.0123) micturitions , and 24-hour (-2.9 vs -1.8; p=0.0010), daytime (-2.2 vs -1.4; p=0.0017), and nocturnal (-0.5 vs-0.3; p=0.0378) urgency episodes.

Significantly greater improvements were also seen on the IPSS storage subscale (-2.6 vs -2.1; p=0.0370), OAB-q symptom bother scale (-17.9 vs -14.4; p=0.0086) and coping domain (15.4 vs 12.4; p=0.0491) in the tolterodine group.

The received wisdom that anticholinergics increase the risk of urinary retention was not seen, with retention episodes occurring in <1% of patients in both arms of the study, with no significant change in postvoid residual volume or maximum urinary flow rate.

The relationship between storage symptoms (frequency, urgency and nocturia) and voiding symptoms (poor flow, hesitancy etc) in men with presumed benign prostatic enlargement is complex. Most men with mixed symptoms are presumed to have benign prostatic obstruction and are treated first with medical therapy targeting the prostate and/or bladder neck (e.g. alpha blockers or

5-alpha reductase inhibitors). It has long been debated whether detrusor overactivity resulting in OAB symptoms (urgency, usually with daytime frequency and nocturia) may develop secondary to bladder outflow obstruction due to benign prostatic enlargement.

However, many men will have OAB symptoms independently of bladder outflow obstruction and these symptoms will often persist despite pharmacological or surgical treatment of outflow obstruction. Given that storage symptoms have a much greater impact on quality of life than voiding symptoms, failure to improve these symptoms adequately will result in poor patient satisfaction with treatment.

This study is directly applicable to patients seen in primary care. It would suggest a safe strategy of initiating an alpha-blocker in patients with mixed storage and voiding symptoms, reviewing at 4-6 weeks, and adding an anticholinergic for those patients whose storage symptoms remain bothersome. It is always possible to trial removing the anticholinergic after a few months of bladder retraining, particularly to see if a placebo effect had a significant role, with therapy reintroduced if storage symptoms relapse.

It is vital for GPs to be aware of the huge amount of bother associated with storage symptoms, and to see the improvement of these symptoms as one of the primary aims of medical therapy.