Frequency of subjects who developed ATL by demographic characteristics and by VL level
| Demographic characteristics . | No. of subjects . | No. of ATLs (% of subjects) . | Frequency of ATL by VL level, n (% of subjects in each quartile in Table 2) . | ||
|---|---|---|---|---|---|
| Quartiles 1 and 2 (VL: < 1.60)* . | Quartile 3 (VL: 1.60-4.54) . | Quartile 4 (VL: ≥ 4.54) . | |||
| Total | 1218 | 14 (1.1) | 0 | 1 (0.3) | 13 (4.3) |
| Sex | |||||
| Male | 426 | 4 (0.9) | 0 | 1 (1.1) | 3 (2.0) |
| Female | 792 | 10 (1.3) | 0 | 0 | 10 (6.4) |
| Age, y | |||||
| Younger than 40 | 167 | 0 | — | — | — |
| 40-49 | 200 | 2 (1.0) | 0 | 0 | 2 (3.7) |
| 50-59 | 273 | 3 (1.1) | 0 | 0 | 3 (3.7) |
| 60-69 | 260 | 3 (1.2) | 0 | 0 | 3 (4.5) |
| 70 or older | 318 | 6 (1.9) | 0 | 1 (1.3) | 5 (6.5) |
| First opportunity for HTLV-1 testing | |||||
| Screening | 661 | 4 (0.6) | 0 | 0 | 4 (2.8) |
| Revelation of HTLV-1-positive family | 134 | 2 (1.5) | 0 | 0 | 2 (8.3) |
| During treatment for other diseases | 265 | 7 (2.6) | 0 | 1 (1.8) | 6 (7.0) |
| Unknown | 158 | 1 (0.6) | 0 | 0 | 1 (2.0) |
| Family history of HTLV-1–related diseases | |||||
| Absence or carrier/HU/HAU only | 385 | 5 (1.3) | 0 | 1 (1.0) | 4 (5.0) |
| HAM/TSP | 9 | 0 | — | — | — |
| ATL | 107 | 3 (2.8) | 0 | 0 | 3 (9.7) |
| Leukemia or lymphoma | 36 | 0 | 0 | 0 | 0 |
| Unknown family history | 681 | 6 (0.9) | 0 | 0 | 6 (3.4) |
| Comorbidity | |||||
| Absence | 961 | 10 (1.0) | 0 | 0 | 10 (4.1) |
| Infectious diseases | 45 | 1 (2.2) | 0 | 0 | 1 (5.9) |
| Autoimmune diseases | 29 | 0 | — | — | — |
| Malignant diseases | 80 | 1 (1.3) | 0 | 0 | 1 (5.9) |
| Skin diseases | 16 | 1 (6.3) | 0 | 1 (33.3) | 0 |
| Other disease | 87 | 1 (1.1) | 0 | 0 | 1 (5.3) |
| Demographic characteristics . | No. of subjects . | No. of ATLs (% of subjects) . | Frequency of ATL by VL level, n (% of subjects in each quartile in Table 2) . | ||
|---|---|---|---|---|---|
| Quartiles 1 and 2 (VL: < 1.60)* . | Quartile 3 (VL: 1.60-4.54) . | Quartile 4 (VL: ≥ 4.54) . | |||
| Total | 1218 | 14 (1.1) | 0 | 1 (0.3) | 13 (4.3) |
| Sex | |||||
| Male | 426 | 4 (0.9) | 0 | 1 (1.1) | 3 (2.0) |
| Female | 792 | 10 (1.3) | 0 | 0 | 10 (6.4) |
| Age, y | |||||
| Younger than 40 | 167 | 0 | — | — | — |
| 40-49 | 200 | 2 (1.0) | 0 | 0 | 2 (3.7) |
| 50-59 | 273 | 3 (1.1) | 0 | 0 | 3 (3.7) |
| 60-69 | 260 | 3 (1.2) | 0 | 0 | 3 (4.5) |
| 70 or older | 318 | 6 (1.9) | 0 | 1 (1.3) | 5 (6.5) |
| First opportunity for HTLV-1 testing | |||||
| Screening | 661 | 4 (0.6) | 0 | 0 | 4 (2.8) |
| Revelation of HTLV-1-positive family | 134 | 2 (1.5) | 0 | 0 | 2 (8.3) |
| During treatment for other diseases | 265 | 7 (2.6) | 0 | 1 (1.8) | 6 (7.0) |
| Unknown | 158 | 1 (0.6) | 0 | 0 | 1 (2.0) |
| Family history of HTLV-1–related diseases | |||||
| Absence or carrier/HU/HAU only | 385 | 5 (1.3) | 0 | 1 (1.0) | 4 (5.0) |
| HAM/TSP | 9 | 0 | — | — | — |
| ATL | 107 | 3 (2.8) | 0 | 0 | 3 (9.7) |
| Leukemia or lymphoma | 36 | 0 | 0 | 0 | 0 |
| Unknown family history | 681 | 6 (0.9) | 0 | 0 | 6 (3.4) |
| Comorbidity | |||||
| Absence | 961 | 10 (1.0) | 0 | 0 | 10 (4.1) |
| Infectious diseases | 45 | 1 (2.2) | 0 | 0 | 1 (5.9) |
| Autoimmune diseases | 29 | 0 | — | — | — |
| Malignant diseases | 80 | 1 (1.3) | 0 | 0 | 1 (5.9) |
| Skin diseases | 16 | 1 (6.3) | 0 | 1 (33.3) | 0 |
| Other disease | 87 | 1 (1.1) | 0 | 0 | 1 (5.3) |
ATL indicates adult T-cell leukemia; HTLV-1, human T-cell leukemia virus type 1; VL, HTLV-1 proviral load; HU, HTLV-1 uveitis; HAU, HTLV-1–associated uveitis; HAM, HTLV-1 myelopathy; TSP, tropical spastic paraparesis; and —, not applicable.
The VL was categorized based on quartile cutoff points (the 25th, 50th, and 75th percentiles of the VL distribution) in 1218 HTLV-1 carriers. The unit of VL was copies/100 PBMCs.