Table 1.
Patients’ baseline demographics and stone characteristics
| Group 1 age 75–79 years N = 189 | Group 2 age 80–84 years N = 113 | Group 3 age ≥ 85 N = 64 | p value | |
|---|---|---|---|---|
| Gender, n (%) | 0.021 | |||
| Male | 107 (56.6) | 64 (56.6) | 24 (37.5) | |
| Female | 82 (43.4) | 49 (43.4) | 40 (62.5) | |
| Ethnicity, n (%) | 0.28 | |||
| Asian | 62 (32.8) | 39 (34.5) | 28 (43.8) | |
| Non-Asian | 127 (67.2) | 74 (65.5) | 36 (56.3) | |
| First presentation of stone, n (%) | 137 (72.5) | 90 (79.6) | 55 (85.9) | 0.063 |
| Symptoms on presentationc, n (%)& | ||||
| Hematuria | 15 (7.9) | 8 (7.1) | 6 (9.4) | 0.314 |
| Pain | 79 (41.8) | 43 (38.1) | 21 832.8) | 0.316 |
| Hematuria and pain | 16 (8.5) | 10 (8.8) | 4 (6.3) | 0.309 |
| Elevated creatinined | 12 (6.3) | 22 (19.5) | 8 (12.5) | 0.001 |
| Fever | 26 (13.8) | 25 (22.1) | 21 (32.8) | 0.002 |
| Incidental finding of stone | 23 (12.2) | 19 (16.8) | 7 (10.9) | 0.240 |
| Pre-operative positive urine culture, n (%) | 93 (49.2) | 54 (47.8) | 41 (64.1) | 0.07 |
| Pre-stented, n (%) | 109 (57.7) | 69 (61.1) | 46 (71.9) | 0.183 |
| Stone characteristicsb | ||||
| HU, median (IQR) | 1010 (791–1215) | 900 (555–1200) | 849 (622–1151.25) | 0.127 |
| Multiple stones& | 84 (44.4) | 52 (46) | 31 (48.4) | 0.982 |
| Sizea, mm, median (IQR) | 8 (6–14) | 11.1 (6–15) | 8.0 (5–13) | 0.467 |
| Locationc& | ||||
| Upper pole | 35 (18.5) | 21 (18.6) | 15 (23.4) | 0.773 |
| Mid pole | 68 (36.0) | 39 (34.5) | 28 (43.8) | 0.485 |
| Lower pole | 83 (43.4) | 51(45.1) | 34 (53.1) | 0.234 |
| Renal pelvis | 33 (17.5) | 28 (24.8) | 11 (17.2) | 0.110 |
Bold value stands for significant p value
IQR interquartile range, HU hounsfield unit
aLargest diameter
bThe results include stones as per location both for solitary and in those patients where there were reported multiple stones in different locations
cMore than one choice possible
dDefined as creatinine ≥ 1.2 mg/dL
&Fisher’s test