Table 1.
Baseline demographic and clinical characteristics of iHEART study participants
| Variable | All users in intervention arm (n = 105) | Group 1: Infrequent (<5 times/week) (n = 33) | Group 2: Moderate (>5 and <11 times/week) (n = 44) | Group 3: Frequent (>11 times/week) (n = 28) | P-value |
|---|---|---|---|---|---|
| Demographic | |||||
| Age (years) | 0.53 | ||||
| <65 | 58 (55%) | 24 (41%) | 20 (35%) | 14 (24%) | |
| 65–75 | 36 (34%) | 4 (11%) | 19 (53%) | 13 (36%) | |
| >75 | 11 (11%) | 5 (45%) | 5 (45%) | 1 (10%) | |
| Female | 26 (25%) | 8 (31%) | 13 (50%) | 5 (19%) | 0.54 |
| Race | 0.99 | ||||
| White | 80 (76%) | 28 (35%) | 29 (36%) | 23 (29%) | |
| Black/African-American | 2 (2%) | 1 (50%) | 0 (0%) | 1 (50%) | |
| Asian | 1 (1%) | 0 (0%) | 1 (100%) | 0 (0%) | |
| Unknown/not reported | 22 (21%) | 4 (18%) | 14 (64%) | 4 (18%) | |
| Ethnicity | 0.13 | ||||
| Hispanic/Latino | 10 (10%) | 1 (10%) | 9 (90%) | 0 (0%) | |
| Not Hispanic/Latino | 55 (52%) | 22 (40%) | 19 (35%) | 14 (25%) | |
| Unknown/not reported | 40 (38%) | 10 (25%) | 16 (40%) | 14 (35%) | |
| Clinical characteristics | |||||
| Type of AF | 0.99 | ||||
| Paroxysmal | 70 (67%) | 22 (31%) | 30 (43%) | 18 (26%) | |
| Persistent | 32 (30%) | 10 (31%) | 13 (41%) | 9 (28%) | |
| Unknown/not reported | 3 (3%) | 1 (33%) | 1 (33%) | 1 (33%) | |
| Family history of AF | 17 (16%) | 7 (41%) | 7 (41%) | 3 (18%) | 0.54 |
| Baseline rhythm | 0.96 | ||||
| AF | 68 (65%) | 22 (32%) | 28 (41%) | 18 (27%) | |
| AF/atrial flutter | 37 (35%) | 11 (30%) | 16 (43%) | 10 (27%) | |
| Procedure at enrolment | 0.92 | ||||
| Cardioversion | 49 (47%) | 15 (31%) | 20 (41%) | 14 (29%) | |
| Ablation | 56 (53%) | 18 (32%) | 24 (43%) | 14 (25%) | |
| AF recurrencea | 0.87 | ||||
| Recurrence | 64 (61%) | 19 (30%) | 28 (44%) | 17 (27%) | |
| No recurrence | 41 (39%) | 14 (34%) | 16 (39%) | 11 (27%) | |
| Median weekly number of AF episodesa | 1.4 ± 3.2 | 0.6 ± 1.0 | 1.1 ± 2.0 | 2.8 ± 5.3 | 0.26 |
| Median number of PACsa | 18.8 ± 8.3 | 14.1 ± 7.2 | 19.7 ± 8.6 | 23.1 ± 6.0 | <0.0001 |
| Diabetes | 12 (11%) | 3 (35%) | 9 (75%) | 0 (0%) | 0.03 |
| Hypertension | 61 (58%) | 15 (35%) | 30 (49%) | 16 (26%) | 0.14 |
| Obesity | 35 (33%) | 10 (29%) | 18 (51%) | 7 (20%) | 0.35 |
| History of smoking | 0.79 | ||||
| Current | 5 (5%) | 3 (60%) | 1 (20%) | 1 (20%) | |
| Past | 33 (31%) | 7 (21%) | 17 (52%) | 9 (27%) | |
| None | 67 (64%) | 23 (34%) | 26 (39%) | 18 (27%) | |
| Sleep apnoea | 24 (23%) | 9 (37%) | 10 (42%) | 5 (21%) | 0.69 |
| Heart failure | 18 (17%) | 3 (17%) | 11 (61%) | 4 (22%) | 0.17 |
| TIA or stroke | 10 (10%) | 2 (20%) | 5 (50%) | 3 (30%) | 0.71 |
| Symptoms and QOL | |||||
| AF Effect on QOL (AFEQT) | |||||
| Overall | 65.2 ± 20.5 | 67.2 ± 19.8 | 67.6 ± 19.8 | 60.7 ± 21.9 | 0.48 |
| Symptom burden | 71.6 ± 23.9 | 71.4 ± 22.9 | 80.3 ± 18.0 | 62.0 ± 27.3 | 0.03 |
| Treatment concern | 63.2 ± 27.1 | 70.2 ± 24.4 | 58.2 ± 29.0 | 61.9 ± 27.0 | 0.23 |
| Daily activities | 63.6 ± 26.7 | 62.7 ± 24.3 | 68.3 ± 26.8 | 59.2 ± 28.8 | 0.45 |
| Treatment satisfaction | 72.7 ± 24.0 | 78.8 ± 17.5 | 71.8 ± 29.5 | 67.9 ± 21.9 | 0.23 |
| AF severity (AFSS) | 10.0 ± 7.0 | 9.8 ± 6.8 | 8.9 ± 6.5 | 11.5 ± 7.9 | 0.52 |
| Depressive symptoms | 4.9 ± 5.8 | 4.9 ± 6.8 | 3.9 ± 4.2 | 6.0 ± 6.4 | 0.64 |
| Anxiety symptoms | |||||
| State | 31.5 ± 12.8 | 32.1 ± 14.9 | 31.0 ± 12.0 | 31.5 ± 11.9 | 0.89 |
| Trait | 31.4 ± 11.0 | 31.1 ± 12.7 | 30.3 ± 9.2 | 32.8 ± 11.5 | 0.54 |
| Self-management skills | |||||
| AF knowledge | 7.3 ± 2.0 | 6.9 ± 2.1 | 7.7 ± 1.4 | 7.4 ± 2.3 | 0.38 |
| Controls-attitudes | 26.5 ± 6.1 | 25.5 ± 6.3 | 27.3 ± 6.2 | 26.6 ± 5.9 | 0.55 |
| Self-efficacy in medication adherence | 35.2 ± 5.2 | 34.8 ± 5.4 | 35.4 ± 5.3 | 35.2 ± 5.2 | 0.74 |
| Reported medication adherence | 2.0 ± 0.9 | 1.9 ± 0.9 | 2.0 ± 0.8 | 2.1 ± 1.0 | 0.55 |
| Technology experience | |||||
| Cellphone owner | 83 (99%) | 25 (30%) | 31 (37%) | 27 (33%) | 0.44 |
| Smartphone owner | 75 (89%) | 23 (31%) | 27 (36%) | 25 (33%) | 0.52 |
| Use Internet on smartphone | 68 (82%) | 21 (31%) | 25 (37%) | 22 (32%) | 0.95 |
| Use email on smartphone | 68 (82%) | 21 (31%) | 25 (37%) | 22 (32%) | 0.95 |
| Downloaded apps on smartphone | 66 (80%) | 21 (32%) | 26 (39%) | 19 (29%) | 0.26 |
| Send/receive text messages | 80 (94%) | 25 (31%) | 30 (38%) | 25 (31%) | 0.86 |
| Followed link from text messages | 63 (74%) | 21 (33%) | 23 (37%) | 19 (30%) | 0.65 |
| Use computer at home | 78 (94%) | 23 (29%) | 31 (40%) | 24 (31%) | 0.68 |
| Internet access at home | 82 (96%) | 25 (30%) | 31 (38%) | 26 (32%) | 0.99 |
| Comfort using Internet on computer | 83 (99%) | 25 (30%) | 32 (39%) | 26 (31%) | 0.35 |
a
Data were collected with AliveCor™ device; all other data came from surveys or the electronic health record.
Measures: AF knowledge: AF Knowledge Scale (AFKS); Anxiety symptoms: State-Trait Anxiety Inventory (STAI); Controls-attitudes: Controls-Attitudes Scale-Revised (CAS-R); Depressive symptoms: Patient Health Questionnaire (PHQ-9); Reported medication adherence: Morisky Medication Adherence Scale (MMAS); Self-efficacy in medication adherence: Self-Efficacy in Medication Adherence scale (SEAMS).