Table 1.
Clinicodemographics of the subcohort for developing the clinical nomogram to predict bladder outlet obstruction and of the split-sample subcohort for validation of the nomogram
| Characteristics | Total subjects | Subcohort for nomogram development | Subcohort for split-sample validation | Pa |
|---|---|---|---|---|
| Patients, n (%) | 750 (100.0) | 570 (76.0) | 180 (24.0) | |
| Age (year) | ||||
| Mean (s.d.) | 65.5 (7.5) | 65.6 (7.7) | 65.2 (6.9) | 0.956 |
| Median (range) | 66 (50–90) | 66 (50–90) | 66 (51–87) | |
| History of acute urinary retention, n (%) | 29 (3.9) | 22 (3.9) | 7 (3.9) | 0.891 |
| Number of previous LUTS medication | ||||
| Mean (s.d.) | 3.8 (0.6) | 3.8 (0.7) | 3.8 (0.5) | 0.944 |
| Median (range) | 4.0 (3.0–6.0) | 4.0 (3.0–6.0) | 4.0 (3.0–6.0) | |
| Duration of previous medication (month) | ||||
| Mean (s.d.) | 11.5 (4.2) | 11.4 (5.1) | 11.8 (3.9) | 0.796 |
| Median (range) | 11 (6–18) | 11 (6–17) | 11 (6–18) | |
| Previous LUTS medication, n (%) | ||||
| α-blocker | 750 (100.0) | 570 (100.0) | 180 (100.0) | 0.865 |
| 5α-reductase inhibitor | 541 (72.1) | 418 (73.3) | 123 (68.3) | |
| Anticholinergic | 608 (81.1) | 461 (80.9) | 147 (81.7) | |
| Desmopressin | 188 (25.1) | 142 (24.9) | 46 (25.6) | |
| Cholinergic | 178 (23.7) | 132 (23.2) | 46 (25.6) | |
| Others | 44 (5.9) | 34 (6.0) | 10 (5.6) | |
| IPSS after medication, n (%) | ||||
| 0–7 | 10 (1.3) | 7 (1.2) | 3 (1.7) | 0.902 |
| 8–19 | 507 (67.6) | 390 (68.4) | 117 (65.0) | |
| 20–35 | 233 (31.1) | 173 (30.4) | 60 (33.3) | |
| PSA (ng ml−1) | ||||
| Mean (s.d.) | 3.0 (8.5) | 3.1 (9.1) | 2.7 (8.2) | 0.806 |
| Median (range) | 1.6 (0.2–24.0) | 1.7 (0.4–24.0) | 1.6 (0.2–18.0) | |
| Qmax (ml s−1), n (%)b | ||||
| ≤5 | 50 (6.7) | 37 (6.5) | 13 (7.2) | 0.921 |
| 5.1–10.0 | 153 (20.4) | 111 (19.5) | 42 (23.3) | |
| 10.1–15.0 | 478 (63.7) | 368 (64.6) | 110 (61.1) | |
| 15.1–20.0 | 62 (8.3) | 48 (8.4) | 14 (7.8) | |
| ≥20.1 | 7 (0.9) | 6 (1.0) | 1 (0.6) | |
| PVR after medication (ml)b | ||||
| Mean (s.d.) | 42.2 (73.8) | 42.1 (77.3) | 43.0 (70.1) | 0.781 |
| Median (range) | 20 (0–400) | 20 (0–395) | 22 (0–400) | |
| TPV (ml) | ||||
| Mean (s.d.) | 36.4 (19.8) | 37.0 (20.5) | 36.1 (18.6) | 0.839 |
| Median (range) | 32.2 (9.5–100.0) | 32.8 (10.5–95.0) | 32.1 (9.5–100.0) | |
| TZI (%) | ||||
| Mean (s.d.) | 40.2 (15.7) | 40.6 (15.8) | 39.2 (15.6) | 0.897 |
| Median (range) | 37.8 (14.5–85.0) | 38.6 (15.5–82.0) | 37.1 (14.5–85.0) | |
| BOO, n (%) | 226 (30.1) | 170 (29.8) | 56 (31.1) | 0.412 |
aComparisons between the both subcohorts; bfree uroflowmetry after medication. s.d.: standard deviation; BOO: bladder outlet obstruction; LUTS: lower urinary tract symptoms; IPSS: International Prostate Symptom Score; PSA: prostate-specific antigen; Qmax: maximum flow rate; PVR: postvoid residual; TPV: total prostate volume; TZI: transitional zone index