主催: The Japanese Pharmacological Society, The Japanese Society of Clinical Pharmacology
会議名: WCP2018 (18th World Congress of Basic and Clinical Pharmacology)
開催地: Kyoto
開催日: 2018/07/01 - 2018/07/06
Background
Symptoms of overactive bladder (urgency, frequency, incontinence, nocturia) are sometimes reported as means (implying close to normal distribution of the parameter) or as medians (not making such assumptions). Using data from a large non-interventional study, we have explored whether and how much such data (baseline and treatment outcomes) deviate from a normal distribution.
Methods
We analyzed data from a non-interventional study in which 1335 overactive bladder patients were treated with 30 to 45 mg/day propiverine ER for 12 weeks. Baseline data and improvements upon treatments, were analyzed by the D'Agostino & Pearson omnibus K2 test. To assess implications, means and medians were compared.
Results
Baseline data for urgency, frequency, urgency incontinence, nocturia did not exhibit Gaussian distribution (K2 values of 461, 546, 1584 and 1505, respectively; each P < 0.0001). While means generally overestimated basal symptom severity as compared to medians, the difference was only large for incontinence (urgency: 10.40 vs. 10, frequency: 13.65 vs. 13, incontinence: 3.59 vs. 2, nocturia: 3.34 vs. 3). Considering only patients without incontinence nocturia at baseline did not change this substantially.
Treatment data for urgency, frequency, urgency incontinence, nocturia also did not exhibit Gaussian distribution, regardless whether expressed as absolute (episode number) or relative improvements (% reduction) but differences were again small except for incontinence episodes. For instance, in the subgroup receiving 30 mg propiverine throughout the entire study (n=773), mean vs. median improvements (% reduction from baseline) were 73% vs. 80%, 42% vs. 42%, 83% vs. 100% and 59% vs. 60% for urgency, frequency, urgency incontinence and nocturia, respectively.
Conclusions
We conclude that basal overactive bladder symptoms and treatment responses do not exhibit normal distribution. This leads to an overestimation of basal symptoms and absolute treatment responses and an underestimation of relative treatment responses; these effects were always strongest for incontinence. Therefore, quantitative reporting of overactive bladder symptoms should be based on medians.
