International Prostate Symptom Scores in young asymptomatic American men

To establish 'normal' ranges of responses to the International Prostate Symptom Score (IPSS) questionnaire from a sample of young, asymptomatic men, as the IPSS is useful both clinically and in research studies, but there are little or no data on the normal ranges of the IPSS.

During a previously conducted study of 284 ambulatory men who considered themselves to have normal urinary function, asymptomatic men completed a 24-h urinary diary and the IPSS questionnaire. Diary variables and the IPSS were analysed using nonparametric Kruskal-Wallis and Spearman's tests.

The IPSS was recorded for 243 men aged < 50 years; 153 (63%) were Caucasian, 67 (28%) African-American, 11 (5%) Hispanic and 11 (5%) Asian. Although all men denied lower urinary tract symptoms during study screening, the total IPSS increased with age. Of men aged 18-29 years, 2% reported 'moderate' symptoms (IPSS > 7) compared to 12% of men aged 40-49 years (P = 0.002). No subject reported 'severe' symptoms (IPSS > 19). When responses to individual IPSS questions were analysed, all item scores except frequency (question 2) and hesitancy (question 6) increased with age. Nocturia (question 7) was often reported, and 11% of men aged 18-29 and 31% of men aged 40-49 years reported two or more nightly voids.

In this study, the consistently increasing positive IPSS with ageing in almost all symptom categories suggests underlying changes in urinary habits even in this asymptomatic group. Studies of normal urinary habits remain critically important to understanding normal and abnormal function, both for the design of research studies and for counselling patients.