Table 3.
Change in PACs and secondary endpoints (i.e., systolic blood pressure (SBP), diastolic blood pressure (DBP), serum glucose, serum magnesium) according to treatment group.
| Magnesium (400 mg Daily) Mean (SD) | Placebo Mean (SD) | Intervention Effect Coefficient * (95% CI) | p-Value | |
|---|---|---|---|---|
| Primary outcome (episodes/h) | ||||
| Log PAC burden | 0.94 (0.69, 1.3) ** | 0.73 | ||
| Baseline | 1.26 (1.4) | 1.04 (1.49) | ||
| Follow-up † | 1.16 (1.41) | 1.09 (1.53) | ||
| Change | −0.06 (0.68) | 0.05 (0.75) | ||
| PAC burden | 0.44 (−2.58, 3.46) | |||
| Baseline | 8.5 ± 14 | 20.2 ± 80 | ||
| Follow-up † | 8.1 ± 12 | 14.6 ± 48 | ||
| Change | −0.6 ± 7 | −5.6 ± 33 | ||
| Secondary outcomes | ||||
| Serum magnesium, mEq/L | 0.07 (0.03, 0.12) | 0.002 | ||
| Baseline | 1.74 (0.12) | 1.71 (0.1) | ||
| Follow-up ‡ | 1.8 (0.13) | 1.71 (0.11) | ||
| Change | 0.07 (0.09) | 0 (0.1) | ||
| Serum glucose, mg/dL | ||||
| Baseline | 94.2 (10.6) | 103.2 (40.2) | 2.4 (−3.0, 7.7) | 0.39 |
| Follow-up ‡ | 96.3 (12.2) | 96.2 (13.7) | ||
| Change | 1.8 (7.5) | −7.1 (32.8) | ||
| Serum glucose ¥, mg/dL | ||||
| Baseline | 94.2 (10.6) | 96.2 (11.6) | 2.8 (−0.9, 6.4) | 0.14 |
| Follow-up ‡ | 96.3 (12.2) | 95 (12.4) | ||
| Change | 1.75 (7.5) | −1.21 (6.7) | ||
| Systolic blood pressure, mmHg | 2.9 (−1.8, 7.2) | 0.18 | ||
| Baseline | 119 (14) | 119 (18) | ||
| Follow-up ‡ | 118 (14) | 115 (14) | ||
| Change | −1 (10) | −4 (10) | ||
| Diastolic blood pressure, mmHg | −0.5 (−3.5, 2.5) | 0.74 | ||
| Baseline | 71.8 (8. 7) | 70.6 (10.3) | ||
| Follow-up ‡ | 71.0 (8.8) | 70.8 (8.7) | ||
| Change | −0.5 (7.1) | 0.2 (6.1) | ||
CI, confidence Interval; DBP, diastolic blood pressure; PAC, premature atrial contractions; SD, standard deviation; and SBP, systolic blood pressure. * Adjusted for age (≥65 or <65), and baseline concentration (e.g., when change in glucose is the outcome, models were adjusted for baseline glucose). The numbers of observations included in linear models are 57, 57, 54, 54, 53, 58, and 58 for the outcomes log PAC burden, PAC burden, serum magnesium, serum glucose, serum glucose excluding outlier, systolic blood pressure and diastolic blood pressure, respectively. ** Presented as a ratio of geometric means (i.e., exp(coefficient)). † ZioPatch was worn for a 2-week period, from the follow-up clinic visit (intervention week 10) through the end of the study (intervention week 12). ‡ Follow-up information obtained at clinic visit (intervention week 10). ¥ Outlier removed.