Table 2.
Characteristics of 248 HFE C282Y Homozygotes by HOMA-IR Quartiles
| HOMA-IR quartiles | ||||||
|---|---|---|---|---|---|---|
| Characteristica | 1 (n = 62) | 2 (n = 62) | 3 (n = 62) | 4 (n = 62) | P (quartile 1 vs. 4)b | P (Pearson's r for trend)b |
| HOMA-IR, range | ≤1.26 | 1.27–2.01 | 2.02–3.05 | ≥3.06 | — | — |
| Mean age, year | 50 ± 15 | 51 ± 13 | 51 ± 12 | 58 ± 13 | 0.0016 | 0.2413 (0.7587) |
| Male, % (n) | 30.6 (19) | 43.5 (27) | 38.7 (24) | 59.7 (37) | 0.0010 | 0.1317 (0.8683) |
| Mean BMI, kg/m2 | 24.4 [23.6, 25.5] | 26.7 [25.5, 27.8] | 26.7 [25.5, 27.8] | 31.5 [29.9, 33.3] | <0.0001 | 0.0794 (0.9206) |
| Mean SBP, mm Hg | 121 ± 20 | 124 ± 16 | 126 ± 19 | 133 ± 18 | 0.0005 | 0.0379 (0.9621) |
| Mean DBP, mm Hg | 73 ± 11 | 78 ± 10 | 80 ± 11 | 81 ± 9 | <0.0001 | 0.0569 (0.9431) |
| MP joint hypertrophy, % (n) | 16.1 (10) | 11.3 (7) | 3.2 (2) | 25.8 (16) | 0.1856 | 0.7129 (0.2871) |
| Hepatomegaly, % (n) | 4.8 (3) | 4.8 (3) | 6.5 (4) | 21.0 (13) | 0.0074 | 0.1736 (0.8264) |
| Mean neutrophils ×103/μL | 3.2 [2.9, 3.5] | 3.5 [3.1, 3.9] | 3.7 [3.4, 4.0] | 4.0 [3.6, 4.4] | 0.0020 | 0.0029 (0.9971) |
| Mean lymphocytes ×103/μL | 1.5 [1.3, 1.6] | 1.7 [1.6, 1.8] | 1.7 [1.5, 1.8] | 1.7 [1.5, 1.9] | <0.0001 | 0.2254 (0.7746) |
| Mean ALT, IU/L | 16 [14, 19] | 20 [17, 23] | 23 [19, 26] | 29 [25, 34] | <0.0001 | 0.0101 (0.9899) |
| Mean AST, IU/L | 21 [19, 22] | 22 [20, 24] | 23 [20, 26] | 25 [23, 28] | <0.0001 | 0.0173 (0.9827) |
| CRP >0.5 mg/dL, % (n) | 25.8 (16) | 27.4 (17) | 38.7 (24) | 41.9 (26) | 0.0578 | 0.0434 (0.9566) |
| Mean TS, % | 73 ± 25 | 70 ± 25 | 57 ± 26 | 66 ± 25 | 0.1344 | 0.3686 (−0.6314) |
| Mean SF, μg/L | 279 [205, 380] | 284 [202, 401] | 206 [141, 302] | 313 [222, 441] | 0.6266 | 0.8674 (−0.1326) |
| Metabolic syndrome, % (n) | 0 (0) | 0 (0) | 4.8 (3) | 24.2 (15) | 0.0020 | 0.8671 (0.1329) |
| Diabetes, % (n) | 4.8 (3) | 1.6 (1) | 3.2 (2) | 32.2 (20) | <0.0001 | 0.2569 (0.7431) |
Results are displayed as mean ±1 SD, mean [95% CI], or percentage (n), as appropriate.
Reference ranges: white blood cells 4.0–11.0 × 103/μL; absolute neutrophils 1.6–8.3 × 103/μL; absolute lymphocytes 0.8–5.3 × 103/μL; ALT 0–31 IU/L (F) and 0–40 IU/L (M); AST 0–31 IU/L (F) and 0–37 IU/L (M); and CRP 0–0.5 mg/dL. ALT activity <4 IU/L was imputed as 3 IU/L. CRP <0.3 mg/dL was imputed as 0.2 mg/L. Elevated CRP levels were defined as >0.5 mg/dL. Reference ranges for iron-related analytes included the following: serum iron concentration 45–160 μg/dL (M) and 30–160 μg/dL (F); serum total iron-binding capacity 228–428 μg/dL; and TS 15%–50%; SF 20–300 μg/L (M); SF 10–120 μg/L (F 15–45 year); and SF 10–300 μg/L (F > 45 year). TS <15% was imputed as 7.5%. The reference ranges for serum glucose and serum insulin were 60–115 mg/dL and 0–20 mIU/L, respectively.
Bonferroni correction for 16 comparisons yielded a revised P for significance of <0.0031.
ALT, alanine aminotransferase; AST, aspartate aminotransferase; BMI, body mass index; CRP, C-reactive protein; DBP, diastolic blood pressure; HOMA-IR, homeostasis model assessment-insulin resistance; MP, metacarpophalangeal; SBP, systolic blood pressure; SF, serum ferritin; TS, transferrin saturation.