Table 1
Demographic characteristics for the study sample, stratified by insomnia status
| All patients N = 227 | Insomnia N = 138 | No insomnia N = 89 | P value | ||
|---|---|---|---|---|---|
| Age | Mean ± SD | 55.7 ± 17.2 | 55.8 ± 17.7 | 55.6 ± 16.6 | 0.92 |
| Gender | Male | 122 (53.7%) | 67 (48.6%) | 55 (61.8%) | 0.05 |
| Female | 105 (46.3%) | 71 (51.4%) | 34 (38.2%) | ||
| Marital Status | Married | 25 (11.0%) | 16 (11.6%) | 9 (10.1%) | 0.15 |
| Single | 155 (68.3%) | 88 (63.8%) | 67 (75.3%) | ||
| Divorced/Widowed | 47 (20.7%) | 34 (24.6%) | 13 (14.6%) | ||
| Education level | Illiterate | 100 (44.1%) | 63 (45.7%) | 37 (41.6%) | 0.83 |
| Elementary | 46 (20.3%) | 29 (21.0%) | 17 (19.1%) | ||
| Preparatory | 35 (15.4%) | 21 (15.2%) | 14 (15.7%) | ||
| High school | 22 (9.7%) | 13 (9.4%) | 9 (10.1%) | ||
| University | 24 (10.6%) | 12 (8.7%) | 12 (13.5%) | ||
| Occupation | Employed | 115 (50.7%) | 65 (47.1%) | 50 (56.2%) | 0.51 |
| Unemployed | 112 (49.3%) | 73 (52.9%) | 39 (43.8%) |
Table 2
Association between insomnia status and other characteristics (shift and type of dialysis, lifestyle habits, and underlying medical problems)
| Characteristics | Insomnia N = 138 | No insomnia N = 89 | OR | CI | P value | |
|---|---|---|---|---|---|---|
| Dialysis | ||||||
| Shift | Morning | 60 (54.1%) | 29 (37.7%) | Ref | Ref | - |
| Afternoon | 30 (27.0%) | 35 (45.5%) | 0.41 | 0.21 - 0.80 | 0.009 | |
| Evening | 21 (18.9%) | 13 (16.9%) | 0.78 | 0.34 - 1.78 | 0.56 | |
| Type | Hemodialysis | 111 (80.4%) | 77 (86.5%) | Ref | Ref | - |
| Peritoneal | 27 (19.6%) | 12 (13.5%) | 1.56 | 0.75 - 3.27 | 0.24 | |
| Duration of dialysis | ≤ 12 months | 50 (36.2%) | 27 (30.3%) | Ref | Ref | - |
| 13-48 months | 48 (34.8%) | 38 (42.7%) | 0.68 | 0.36 - 1.28 | 0.24 | |
| 49-84 months | 21 (15.2%) | 18 (20.2%) | 0.63 | 0.29 - 1.38 | 0.25 | |
| > 84 | 19 (13.8%) | 6 (6.7%) | 1.71 | 0.61 - 4.79 | 0.31 | |
| Lifestyle characteristics | ||||||
| BMI categories | Normal | 60 (43.5%) | 39 (43.8%) | Ref | Ref | - |
| Overweight | 46 (33.3%) | 26(29.2%) | 1.15 | 0.61 - 2.15 | 0.66 | |
| Obese | 32 (23.2%) | 24 (27.0%) | 0.87 | 0.45 - 1.69 | 0.67 | |
| Smoking | Smoker | 28 (20.3%) | 24 (27.0%) | Ref | Ref | - |
| Ex/Nonsmoker | 110 (79.7%) | 65 (73.%) | 0.69 | 0.37 - 1.29 | 0.24 | |
| Coffee intake | Yes | 102 (73.9%) | 70 (78.7%) | Ref | Ref | - |
| No | 36 (26.1%) | 19 (21.3%) | 0.77 | 0.41 - 1.45 | 0.42 | |
| Medical conditions | ||||||
| DM | Yes | 73 (52.9%) | 46 (51.7%) | Ref | Ref | - |
| No | 65 (47.1%) | 43 (48.3%) | 1.05 | 0.62 - 1.79 | 0.86 | |
| Hypertension | Yes | 117 (84.8%) | 73 (82.0%) | Ref | Ref | - |
| No | 21 (15.2%) | 16 (18.0%) | 1.22 | 0.60 - 2.49 | 0.58 | |
| Erythropoietin & iron supply | Yes | 135 (97.8%) | 84 (94.4%) | Ref | Ref | - |
| No | 3 (2.2%) | 5 (5.6%) | 2.68 | 0.62 - 11.5 | 0.19 | |
| Biochemical parameters | ||||||
| KTV (Hemodialysis) | ≥1.2 | 89 (89.9%) | 65 (89.0%) | Ref | Ref | - |
| < 1.2 | 10 (10.1%) | 8 (11.0%) | 0.91 | (0.34-2.44) | 0.86 | |
| KTV (Peritoneal dialysis) | ≥1.7 | 15 (75.0%) | 7 (77.8%) | Ref | Ref | - |
| < 1.7 | 5 (25.0%) | 2 (22.2%) | 1.17 | (0.18-7.56) | 0.87 | |
| Albumin | Normal | 118 (87.4%) | 74 (85.1%) | Ref | Ref | - |
| Low | 17 (12.6%) | 13 (14.9%) | 0.82 | (0.38-1.79) | 0.62 | |
| Hgb | Normal | 59 (44.7%) | 34 (40.5%) | Ref | Ref | - |
| Low | 73 (55.3%) | 50 (59.5%) | 0.84 | (0.48-1.47) | 0.54 | |
| 2.10-2.55 (Normal) | 90 (66.7%) | 63 (74.1%) | Ref | Ref | - | |
| Calcium | < 2.10 | 33 (24.4%) | 20 (23.5%) | 1.16 | (0.61-2.20) | 0.66 |
| > 2.55 | 12 (8.9%) | 2 (2.4%) | 4.20 | (0.91-19.42) | 0.05 | |
| Normal | 66 (50.0%) | 40 (48.2%) | Ref | Ref | - | |
| Phosphorus | Low | 8 (6.1%) | 7 (8.4%) | 0.69 | (0.23-2.06) | 0.51 |
| High | 58 (43.9%) | 36 (43.4%) | 0.98 | (0.55-1.73) | 0.94 | |
| Ferritin | ||||||
| Normal | 42 (33.6%) | 29 (35.8%) | Ref | Ref | - | |
| Low | 0 (0.0%) | 2 (2.5%) | - | - | - | |
| High | 83 (66.4%) | 50 (60.2%) | 1.15 | (0.64-2.07) | 0.65 | |
Table 3
Association between insomnia and other sleep disturbances
| Other sleep disorders | Insomnia N = 138 | No insomnia N = 89 | OR | CI | P value | |
|---|---|---|---|---|---|---|
| RLS | Positive | 86 (62.3%) | 28 (31.5%) | Ref | Ref | - |
| Negative | 52 (37.7%) | 61 (68.5%) | 2.18 | 1.18 - 4.06 | 0.01 | |
| PSQI | Good Sleep | 0 (0.0%) | 3 (3.4%) | Ref | Ref | - |
| Bad Sleep | 138 (100.0%) | 86 (96.6%) | NA | NA | NA | |
| Berlin | Low risk | 22 (16.2%) | 36 (43.4%) | Ref | Ref | - |
| High risk | 114 (83.8%) | 47 (56.6%) | 2.10 | 1.15 - 3.81 | 0.02 | |
| ESS | Positive | 78 (56.5%) | 22 (24.7%) | Ref | Ref | - |
| Negative | 60 (43.5%) | 67 (75.3%) | 2.13 | 1.09 - 4.15 | 0.03 | |
Table 4
Patient responses to insomnia questions
| Total = 227 | < 1 month | > 1 month* | |
|---|---|---|---|
| 1- Do you often have difficulty falling asleep? | 121 (53.3%) | 5 (2.2. %) | 116 (51.1%) |
| 2- Do you have frequent awakening with difficulty falling asleep again? | 131 (57.7%) | 5 (2.2%) | 126 (55.5%) |
| 3- Do you wake up too early? | 133 (58.6%) | 4 (1.7%) | 129 (56.8%) |
| 4- Do you often feel tired when you awaken in the morning due to sleep loss? | 147 (64.8%) | 6 (2.6%) | 141 (62.1%) |
| 5- Does sleep loss affect your mood during the day, making you feel tense, irritable or depressed? | 107 (47.1%) | 2 (0.88%) | 105 (46.2%) |
*Some patients had more than one answer