Table 3.
Cause-specific hospitalizations in heart failure patients for serum potassium ≤4 mEq/L
| Cause for hospitalization* | Rate/10,000 person-years follow up (number of events/follow-up in years) | Rate difference* (/10,000 person-years) | Matched hazard ratio (95% confidence interval)† | P value | |
|---|---|---|---|---|---|
| Serum potassium ≥4 mEq/L (N = 1187) | Serum potassium <4 mEq/L (N = 1187) | ||||
| All-cause | 3846 (768/1997) | 4243 (796/1876) | + 397 | 1.12 (0.99–1.27) | 0.073 |
| Cardiovascular | 3621 (865/2389) | 3980 (888/2231) | + 359 | 1.13 (0.99–1.29) | 0.082 |
| Worsening heart | 1766 (509/2883) | 2004 (546/2725) | + 238 | 1.14 (0.99–1.31) | 0.075 |
| Ventricular arrhythmia, | 172 (58/3369) | 169 (55/3261) | − 3 | 0.94 (0.59–1.52) | 0.808 |
| SV arrhythmias§ | 194 (65/3359) | 255 (82/3218) | + 61 | 1.20 (0.79–1.83) | 0.394 |
| AV block, bradyarrhythmia | 17 (6/3434) | 24 (8/3308) | +7 | 2.50 (0.49–12.89) | 0.273 |
| Suspected digoxin toxicity | 76 (26/3400) | 66 (22/3303) | −10 | 0.61 (0.29–1.29) | 0.198 |
| Myocardial infarction | 265 (89/3361) | 320 (104/3249) | + 55 | 1.40 (0.96–2.05) | 0.085 |
| Unstable angina | 683 (218/3193) | 644 (196/3042) | − 39 | 1.20 (0.92–1.57) | 0.176 |
| Stroke | 242 (81/3354) | 265 (86/3247) | + 23 | 0.85 (0.55–1.30) | 0.448 |
| Coronary revascularization¶ | 82 (28/3395) | 104 (34/3272) | +21 | 1.19 (0.61–2.31) | 0.613 |
| Cardiac transplantation | 53 (18/3421) | 21 (7/3300) | −32 | 0.86 (0.29–2.55) | 0.782 |
| Other cardiovascular** | 632 (203/3211) | 687 (209/3043) | + 55 | 1.11 (0.85–1.45) | 0.453 |
| Respiratory infection | 415 (138/3327) | 382 (122/3196) | −33 | 1.06 (0.76–1.50) | 0.728 |
| Other non-cardiovascular | 2054 (561/2731) | 2086 (554/2656) | + 32 | 1.03 (0.87–1.21) | 0.735 |
| Unspecified | 23 (8/3425) | 18 (6/3311) | −5 | 0.75 (0.17–3.35) | 0.706 |
| Number of hospitalizations | 14696 (3389/2306) | 13708 (3438/2508) | −988 | ||
Data shown include the first hospitalization of each patient due to each cause.
Absolute rate differences were calculated by subtracting the rates of hospitalization in the normal-potassium group from the rates of hospitalization in the low-potassium group
Hazard ratios and confidence intervals (CI) were estimated from a Cox proportional-hazards models that used the first hospitalization of each patient for each reason.
Supraventricular (SV) arrhythmias include Atrioventricular (AV) block and bradyarrhythmias
This category includes coronary-artery bypass grafting and percutaneous transluminal coronary angioplasty
This category includes embolism, venous thrombosis, peripheral vascular disease, hypertension, other vascular surgery, cardiac catheterization, other types of catheterization, pacemaker implantation, installation of automatic implantable cardiac defibrillator, electrophysiologic testing, transplant-related evaluation, nonspecific chest pain, atherosclerotic heart disease, hypotension, orthostatic hypotension, and valve operation