Table 1.
Demographic characteristics according to MIC and classifications equally divided by two baseline biomarkers
| A | B | C | D | E | P value | |
|---|---|---|---|---|---|---|
| Range of biomarkers | ||||||
| MIC based on AHTKV-α (%/year) | < 1.5 | 1.5–3.0 | 3.0–4.5 | 4.5–6.0 | ≥ 6.0 | |
| Baseline AHTKV-α (%/year) | < 2.59 | 2.59–3.47 | 3.47–4.34 | 4.34–5.27 | ≥ 5.27 | |
| Baseline-measured HtTKV slope (%/year) | < − 2.05 | − 2.05–2.9 | 2.9–6.85 | 6.85–11.1 | ≥ 11.1 | |
| Patient number (male/female) | ||||||
| MIC based on AHTKV-α | 11 (3/8) | 69 (19/50) | 112 (42/70) | 80 (36/44) | 24 (13/11) | 0.0893 |
| Baseline AHTKV-α | 59 (16/43) | 59 (15/44) | 60 (25/35) | 59 (27/32) | 59 (30/29) | 0.0107 |
| Baseline-measured HtTKV slope | 59 (14/45) | 59 (22/37) | 60 (27/33) | 59 (22/37) | 59 (28/31) | 0.0721 |
| Baseline age (year) | ||||||
| MIC based on AHTKV-α | 55.9 (10.5) | 49.6 (14.8) | 49.7 (13.3) | 40.5 (10.3) | 33.6 (7.7) | < 0.0001 |
| Baseline AHTKV-α | 51.4 (14.3) | 50.8 (14.1) | 49.0 (13.4) | 43.7 (9.4) | 35.8 (10.0) | < 0.0001 |
| Baseline-measured HtTKV slope | 49.3 (13.1) | 48.4 (14.4) | 43.8 (12.9) | 47.7 (13.5) | 41.5 (13.1) | 0.0061 |
| Baseline TKV (mL) | ||||||
| MIC based on AHTKV-α | 485.2 (237.2) | 814.0 (94.7) | 1634.4 (74.3) | 2150.2 (88.0) | 2518.3 (160.6) | < 0.0001 |
| Baseline AHTKV-α | 694.6 (251.5) | 1221.8 (506.3) | 1745.7 (800.9) | 2053.0 (884.8) | 2340.2 (1150.1) | < 0.0001 |
| Baseline-measured HtTKV slope | 1672.2 (943.5) | 1628.1 (1023.8) | 1540.9 (997.7) | 1760.2 (1011.0) | 1457.3 (903.0) | 0.4954 |
| Baseline HtTKV (mL/m) | ||||||
| MIC based on AHTKV-α | 308.1 (52.0) | 512.1 (225.3) | 1004.8 (459.5) | 1296.5 (652.8) | 1503.2 (629.4) | < 0.0001 |
| Baseline AHTKV-α | 435.6 (163.7) | 765.8 (331.8) | 1066.4 (498.9) | 1243.6 (541.7) | 1403.7 (712.5) | < 0.0001 |
| Baseline-measured HtTKV slope | 1040.2 (591.5) | 1000.2 (618.2) | 944.6 (628.5) | 1062.5 (602.2) | 869.7 (528.3) | 0.4023 |
| Age at ADPKD diagnosis (year) | ||||||
| MIC based on AHTKV-α | 53.5 (10.8) | 42.7 (12.7) | 41.0 (12.6) | 32.5 (8.9) | 24.0 (7.9) | < 0.0001 |
| Baseline AHTKV-α | 45.5 (13.1) | 42.7 (13.8) | 39.0 (11.7) | 35.4 (9.0) | 27.6 (8.8) | < 0.0001 |
| Baseline-measured HtTKV slope | 38.4 (13.5) | 40.6 (13.6) | 36.8 (11.5) | 38.6 (14.9) | 36.4 (11.1) | 0.4773 |
| Age at onset of disease manifestations (year) | ||||||
| MIC based on AHTKV-α | 49.8 (12.2) | 41.9 (13.5) | 40.4 (11.7) | 31.4 (9.1) | 25.4 (8.2) | < 0.0001 |
| Baseline AHTKV-α | 44.2 (13.0) | 42.6 (12.6) | 38.6 (12.1) | 33.6 (9.8) | 27.9 (8.7) | < 0.0001 |
| Baseline-measured HtTKV slope | 40.1 (13.7) | 39.5 (12.7) | 36.3 (12.8) | 36.7 (12.4) | 43.4 (11.5) | 0.1260 |
| Age at onset of HTN (year) (n = 194) | ||||||
| MIC based on AHTKV-α | 47.8 (11.8) | 46.4 (11.5) | 43.2 (10.7) | 35.0 (7.8) | 29.2 (6.8) | < 0.0001 |
| Baseline AHTKV-α | 48.2 (12.5) | 44.7 (10.0) | 42.3 (10.7) | 36.4 (8.0) | 31.9 (8.1) | < 0.0001 |
| Baseline-measured HtTKV slope | 44.4 (12.5) | 41.4 (10.1) | 40.4 (12.7) | 38.6 (10.4) | 36.6 (9.0) | 0.0192 |
| Hypertensive patients, % (n = 267) | ||||||
| MIC based on AHTKV-α | 55.6 | 64.6 | 86.5 | 77.3 | 95.5 | 0.0015 |
| Baseline AHTKV-α | 58.9 | 82.4 | 88.7 | 81.5 | 81.1 | 0.0021 |
| Baseline-measured HtTKV slope | 85.7 | 73.1 | 70.4 | 83.3 | 78.4 | 0.2445 |
Values are mean (SD) for continuous variables. Using MIC, subgroups A–E correspond to the original subgroups 1A–1E. Baseline age was age at the initial measurement of TKV. Family history and hypertension data were not available for 26 and 29 patients, respectively. P values were obtained by ANOVA for continuous variables and by Pearson Chi-squared test for categorical variables
MIC Mayo Clinic Image Classification for ADPKD, AHTKV-α age- and height-adjusted TKV growth rate as described in the text, TKV total kidney volume, HtTKV height-adjusted TKV, eGFR estimated glomerular filtration rate calculated using serum creatinine according to the Isotope Dilution Mass Spectrometry and Modification of Diet in Renal Disease (IDMS–MDRD) with the Japanese coefficient, HTN hypertension