Comparisons of demographic and clinical characteristics among the latent classes
| Variable | Class 1 (n=79) | Class 2 (n=74) | Class 3 (n=63) | P value |
| Age (mean±SD), years | 58.7±10.4 | 61.5±9.5 | 60.8±11.4 | 0.239 |
| Sex | 0.258 | |||
| Male | 35 (44.3%) | 32 (43.2%) | 20 (31.7%) | |
| Female | 44 (55.7%) | 42 (56.8%) | 43 (68.3%) | |
| Marital status | 0.320 | |||
| Married | 8 (10.1%) | 3 (4.1%) | 6 (9.5%) | |
| Separated/divorced/widowed | 71 (89.9%) | 71 (95.9%) | 57 (90.5%) | |
| Educational background | 0.477 | |||
| Junior high school or below | 53 (67.1%) | 54 (73.0%) | 46 (73.0%) | |
| High school | 12 (15.2%) | 14 (18.9%) | 9 (14.3%) | |
| University or above | 14 (17.7%) | 6 (8.1%) | 8 (12.7%) | |
| Employment status | 0.814 | |||
| Employed | 6 (7.6%) | 5 (6.8%) | 3 (4.8%) | |
| Medical leave | 2 (2.5%) | 5 (6.8%) | 3 (4.8%) | |
| Unemployed | 25 (31.7%) | 23 (31.1%) | 20 (31.7%) | |
| Retired | 28 (35.4%) | 31 (41.8%) | 23 (36.5%) | |
| Others | 18 (22.8%) | 10 (13.5%) | 14 (22.2%) | |
| Monthly family income (¥) | 0.001 | |||
| <5000 | 50 (63.3%) | 64 (86.5%) | 52 (82.5%) | |
| ≥5000 | 29 (36.7%) | 10 (13.5%) | 11 (17.5%) | |
| MM type | 0.797 | |||
| IgG type | 42 (53.1%) | 43 (58.1%) | 34 (54.0%) | |
| IgA type | 28 (35.4%) | 27 (36.4%) | 24 (38.1%) | |
| IgD type | 4 (5.1%) | 1 (1.4%) | 4 (6.3%) | |
| Light chain type | 4 (5.1%) | 2 (2.7%) | 1 (1.6%) | |
| Others | 1 (1.3%) | 1 (1.4%) | 0 (0.0%) | |
| Disease stage | 0.056 | |||
| New diagnosis | 6 (7.6%) | 2 (2.7%) | 5 (7.9%) | |
| Induction chemotherapy | 34 (43.1%) | 31 (41.9%) | 26 (41.3%) | |
| Consolidation chemotherapy | 22 (27.8%) | 25 (33.8%) | 15 (23.8%) | |
| Platform stage | 14 (17.7%) | 7 (9.4%) | 6 (9.5%) | |
| Unclear | 2 (2.5%) | 4 (5.4%) | 1 (1.6%) | |
| Recurrence | 1 (1.3%) | 5 (6.8%) | 10 (15.9%) | |
| Use of painkillers, antidepressants or hypnotic drugs | <0.001 | |||
| No | 71 (89.9%) | 59 (79.7%) | 39 (61.9%) | |
| Yes | 8 (10.1%) | 15 (20.3%) | 24 (38.1%) | |
| Complications | ||||
| No | 2 (2.5%) | 1 (1.4%) | 2 (3.2%) | 0.860 |
| Multiple myeloma bone disease | 20 (25.3%) | 41 (55.4%) | 36 (57.1%) | <0.001 |
| Impairment of renal function | 9 (11.4%) | 9 (12.2%) | 14 (22.2%) | 0.143 |
| Anaemia | 17 (21.5%) | 26 (35.1%) | 28 (44.4%) | 0.014 |
| Hypercalcaemia | 2 (2.5%) | 0 (0.0%) | 3 (4.8%) | 0.197 |
| Thrombosis | 1 (1.3%) | 3 (4.1%) | 1 (1.6%) | 0.531 |
| Inflammation | 16 (20.3%) | 16 (21.6%) | 8 (12.7%) | 0.355 |
| Other complications | 28 (35.4%) | 13 (17.6%) | 12 (19.0%) | 0.017 |
| Treatments | 0.804 | |||
| Oral drug therapy | 3 (3.8%) | 4 (5.4%) | 1 (1.6%) | |
| Chemotherapy | 64 (81.0%) | 55 (74.3%) | 51 (81.0%) | |
| Autologous haematopoietic stem cell transplantation | 5 (6.3%) | 9 (12.2%) | 5 (7.9%) | |
| Others | 7 (8.9%) | 6 (8.1%) | 6 (9.5%) | |
| BMI | 0.198 | |||
| <18.5 | 6 (7.6%) | 2 (2.7%) | 6 (9.5%) | |
| 18.5–23.9 | 50 (63.3%) | 52 (70.3%) | 34 (54.0%) | |
| 24–27.9 | 20 (25.3%) | 13 (17.6%) | 19 (30.2%) | |
| >27.9 | 3 (3.8%) | 7 (9.5%) | 4 (6.3%) | |
| Daily sleep time (mean±SD), hours | 7.2±1.4 | 6.7±1.4 | 6.5±1.5 | 0.014 |
| Daily step counts | 0.043 | |||
| <5000 | 49 (62.0%) | 54 (73.0%) | 51 (81.0%) | |
| ≥5000 | 30 (38.0%) | 20 (27.0%) | 12 (19.0%) |
BMI, body mass index; MM, multiple myeloma.