Table 2.
Characteristics | Vitamin D metabolite diagnostic ratio |
||
---|---|---|---|
VMDR <25 (N = 848) | VMDR 25–80 (N = 118) | VMDR >80 (N = 8) | |
Males | 604 (71.2%) | 68 (57.6%) | 5 (62.5%) |
Age, years | 47.4 (14.2) | 47.8 (15.5) | 51.1 (15.2) |
Age at first self-reported stone event | 37.1 (14.1) | 36.2 (15.0) | 29.3 (9.0) |
Age at first stone composition analysis | 45.6 (14.3) | 46.6 (16.7) | 48.3 (17.7) |
Body mass index, kg/m2 | 27.0 (4.8) | 28.1 (5.4) | 24.9 (2.7) |
eGFR creatinine Equation CKD-EPI 2009, ml/min per 1.73 m2 BSA | 95.4 (18.7) | 93.6 (25.0) | 80.2 (25.4) |
Hypertension medication usage | 232 (27.4%) | 34 (28.8%) | 2 (25.0%) |
Diabetes | 94 (11.1%) | 20 (16.9%) | 0 (0.0%) |
Stone recurrence (≥2 stone events) | 689 (81.3%) | 96 (81.4%) | 8 (100.0%) |
Medications affecting plasma 25(OH) vitamin D3 | 55 (6.5%) | 15 (12.7%) | 1 (12.5%) |
Loop diuretics | 11 (1.3%) | 3 (2.5%) | 0 (0.0%) |
Thiazide diuretics | 115 (13.6%) | 11 (9.3%) | 1 (12.5%) |
DEXA parameters | |||
Femoral neck BMD, g/cm2 | 0.84 (0.76, 0.93) | 0.79 (0.72, 0.88) | 0.79 (0.65, 0.84) |
Femoral neck T-score, SD | −0.50 (−1.20, 0.10) | −0.80 (−1.48, −0.20) | −1.05 (−2.00, −0.70) |
Lumbar spine BMD, g/cm2 | 1.02 (0.94, 1.11) | 0.98 (0.85, 1.08) | 1.01 (0.97, 1.06) |
Lumbar spine T-score, SD | −0.60 (−1.28, 0.30) | −0.70 (−2.00, 0.18) | −0.70 (-0.98, −0.28) |
Blood parameters | |||
Total plasma calcium, mmol/l | 2.34 (2.28, 2.39) | 2.32 (2.26, 2.39) | 2.43 (2.34, 2.53) |
Corrected plasma calcium, mmol/l | 2.36 (2.30, 2.42) | 2.36 (2.29, 2.43) | 2.46 (2.34, 2.54) |
Ionized calcium, mmol/l | 1.20 (1.17, 1.22) | 1.20 (1.18, 1.23) | 1.24 (1.21, 1.26) |
Phosphate, mmol/l | 1.00 (0.88, 1.11) | 0.98 (0.87, 1.10) | 0.96 (0.91, 1.01) |
25(OH) vitamin D3, ng/ml | 22.00 (16.00, 30.00) | 12.00 (8.30, 18.00) | 12.50 (9.00, 31.30) |
1,25(OH)2 vitamin D3, pmol/l | 100.00 (76.00, 127.00) | 90.00 (67.00, 121.00) | 81.50 (72.50, 105.00) |
Total 24,25(OH)2 vitamin D ng/ml | 1.65 (0.96, 2.44) | 0.37 (0.24, 0.57) | 0.12 (0.07, 0.14) |
Intact PTH, ng/l | 38.60 (30.40, 49.00) | 44.00 (32.00, 59.50) | 42.00 (21.40, 45.00) |
cFGF23, RU/ml | 69.30 (54.20, 94.80) | 71.10 (55.20, 111.50) | 94.80 (65.70, 236.20) |
Urine parameters | |||
Urinary calcium, mmol/24h | 5.20 (3.43, 7.48) | 4.51 (2.66, 7.15) | 9.52 (6.07, 10.30) |
Fractional excretion of calcium, % | 2.72 (1.84, 3.56) | 2.66 (1.55, 3.55) | 3.59 (2.95, 5.24) |
RSS for calcium oxalate | 4.00 (2.00, 7.50) | 5.00 (2.70, 8.60) | 5.70 (2.60, 7.90) |
RSS for brushite | 0.70 (0.30, 2.00) | 1.00 (0.30, 3.10) | 1.30 (0.40, 4.70) |
Relative kidney stone composition ≥ 50% | |||
Total calcium oxalate | 525 (79.4%) | 65 (77.4%) | 5 (83.3%) |
Calcium oxalate monohydrate | 354 (54.4%) | 44 (53.7%) | 1 (16.7%) |
Calcium oxalate dihydrate | 112 (17.2%) | 16 (19.5%) | 4 (66.7%) |
Total calcium phosphate | 76 (11.5%) | 14 (16.7%) | 1 (16.7%) |
Apatite | 53 (8.0%) | 9 (10.7%) | 1 (16.7%) |
Brushite | 12 (1.8%) | 3 (3.6%) | 0 (0.0%) |
Uric acid | 57 (8.6%) | 3 (3.6%) | 0 (0.0%) |
Cystine | 8 (1.2%) | 1 (1.2%) | 0 (0.0%) |
BMD, bone mineral density; BSA, body surface area; cFGF23, C-terminal fibroblast growth factor 23; CKD-EPI, Chronic Kidney Disease-Epidemiology Collaboration; DEXA, dual-energy X-ray absorptiometry; eGFR, estimated glomerular filtration rate; PTH, parathyroid hormone; VMDR, Vitamin D metabolite diagnostic ratio.
Categorical variables are described by number of participants N (%), continuous variables are described by their mean (SD) or median (25th–75th percentile).