Figure 1: Kaplan-Meier survival curves for all-cause mortality or AF-related rehospitalization in patients having atleast 1 comorbidity vs patients with AF alone.
Log Rank Chi-Square 21.71, 1df, p<0.001
Parameters |
Patients admitted with a primary diagnosis of AF /flutter (from New South Wales) N = 1664 |
Age, years |
68.0 (58.0 – 77.0) |
Age ≥ 75 years old |
540 (32.5%) |
Males |
928 (55.8%) |
Aboriginal / Torres Strait Islander |
16 (1.0%) |
Born in Australia |
854 (51.3%) |
Admitted via Emergency Department |
1129 (67.8%) |
Additional diagnosis during current admission |
1444 (86.8%) |
Length of hospital stay, days (IQR) |
2.0 (1.0 – 4.0) |
ICU* admissions |
20 (1.2%) |
Length of ICU stay (for patients admitted to ICU), hours (IQR) |
44.5 (13.5 – 132.5) |
Composite score |
|
‡CHA2DS2VASc score |
2.0 (1.0 – 3.0) |
AF related procedures |
|
Electrical cardioversion |
213 (12.8%) |
Pulmonary vein isolation |
91 (5.5%) |
Current comorbidities |
|
Cardiac risk factors: |
|
Hypertension |
630 (37.9%) |
Smoking |
415 (24.9%) |
Diabetes mellitus |
341 (20.5%) |
Obesity |
90 (5.4%) |
Alcohol consumption |
18 (1.1%) |
Hypercholesterolaemia |
6 (0.4%) |
Cardiac conditions: |
|
Heart failure |
178 (10.7%) |
Ischaemic heart disease |
149 (9.0%) |
Acute coronary syndromes: Unstable angina or Myocardial infarction |
30 (1.8%) |
Atrioventricular block |
28 (1.7%) |
Supraventricular tachycardia |
25 (1.5%) |
Ventricular tachycardia or ventricular fibrillation |
23 (1.4%) |
Sick sinus syndrome |
23 (1.4%) |
Pulmonary embolism |
9 (0.5%) |
Cerebral infarction |
7 (0.4%) |
Peripheral vascular disease |
3 (0.2%) |
Cardiac arrest |
3 (0.2%) |
Transient ischaemic attack |
2 (0.1%) |
Non-cardiac conditions: |
|
COPD† |
124 (7.5%) |
Chronic kidney disease |
107 (6.4%) |
Acute kidney failure |
84 (5.0%) |
Asthma |
61 (3.7%) |
Anaemia |
59 (3.5%) |
Thyrotoxicosis |
24 (1.4%) |
Hyperkalaemia |
24 (1.4%) |
Obstructive sleep apnoea |
15 (0.9%) |
Sepsis (flagged for sepsis) |
13 (0.8%) |
Pulmonary hypertension |
3 (0.2%) |
Presenting symptoms in patients presenting via ED (N = 1129) |
1006 (89.1%) |
Syncope |
38 (3.4%) |
Chest pain |
363 (32.2%) |
Shortness of breath |
120 (10.6%) |
Palpitations |
438 (38.8%) |
Dizziness |
46 (4.1%) |
Continuous variables are expressed as medians with interquartile range in brackets; all others represent numbers of patients with values in brackets representing percentages.
Abbrevations: *ICU: Intensive Care Unit
†COPD: Chronic obstructive pulmonary disease
‡CHA2DS2VASc score is calculated by adding points for each of the following:
Congestive heart failure: 1 point, Hypertension: 1 point, Age = 75 years: 2 points; Age 65 – 74: 1 point, Diabetes: 1 point, Stroke / TIA/ Thromboembolism: 2 points, Vascular disease (prior myocardial infarction, peripheral artery disease or aortic plaque): 1 point, Sex category (Female sex): 1 point
Table 1: Baseline patient characteristics during index acute AF/flutter admission at Westmead Hospital from 1 May 2014 to 31 May 2018
Parameters |
Patients admitted with a primary diagnosis of AF /flutter (from New South Wales) |
AF-related rehospitalization for: recurrent AF/flutter, CHF, MI and / or stroke |
|
Clinical outcomes at short-term follow-up (30 days) |
|
30-day AF-related rehospitalization |
123 (7.4%) |
30-day rehospitalization with a primary diagnosis of AF/flutter |
110 (6.6%) |
30-day rehospitalization with a primary diagnosis of CHF, MI or stroke |
13 (0.8%) |
First composite outcome during long-term follow-up: AF-related rehospitalization or all-cause mortality (over a mean follow-up of 2.1 ± 1.5 years) |
|
1st AF-related rehospitalization OR all-cause mortality |
683 (41.0%) |
1st rehospitalization with a primary diagnosis of AF/flutter AF/flutter only |
549 (33.0%) 483 (29.0%) |
1st rehospitalization with a primary diagnosis of CHF, MI or stroke |
85 (5.1%) |
All-cause mortality |
|
Deaths during initial admission |
9 (0.5%) |
Deaths (till end of study 31 May 2019) |
119 (7.2%) |
Cumulative event rate |
|
AF-related rehospitalization within 1 year of initial admission |
436 (26.2%) |
All-cause mortality within 1 year of initial admission |
56 (3.4%) |
Table 2: AF-related outcomes of AF/flutter patients admitted to Westmead Hospital from 1 May 2014 to 31 May 2018 and followed up till 31 May 2019
Univariable analysis |
|||
Parameters |
Unadjusted Odds Ratio |
95% Confidence Interval |
p value |
Age at episode, per 1 year |
1.02 |
1.00 – 1.03 |
0.016 |
Age at episode ≥ 75 years |
1.52 |
1.05 – 2.22 |
0.027 |
Males |
0.82 |
0.57 – 1.19 |
0.29 |
Aboriginal and Torres Strait Islander |
0.83 |
0.11 – 6.35 |
0.86 |
Length of hospital stay |
0.99 |
0.96 – 1.03 |
0.62 |
Admission via Emergency |
1.75 |
1.13 – 2.72 |
0.013 |
Having ≥1 comorbidity |
2.01 |
1.00 – 4.02 |
0.049 |
Hypertension |
1.46 |
1.01 – 2.11 |
0.045 |
Diabetes |
1.28 |
0.83 – 1.96 |
0.27 |
Obesity |
1.24 |
0.58 – 2.62 |
0.58 |
Smoking |
0.88 |
0.57 – 1.36 |
0.56 |
Alcohol consumption |
0.74 |
0.10 – 5.57 |
0.77 |
Ischaemic heart disease |
1.22 |
0.67 – 2.23 |
0.52 |
Heart failure |
1.08 |
0.60 – 1.93 |
0.80 |
Sick sinus syndrome |
0.57 |
0.08 – 4.23 |
0.58 |
Chronic kidney disease |
2.38 |
1.35 – 4.20 |
0.003 |
Acute kidney failure |
1.34 |
0.63 – 2.85 |
0.45 |
Asthma |
1.66 |
0.74 – 3.73 |
0.22 |
Chronic obstructive pulmonary disease |
1.52 |
0.83 – 2.79 |
0.17 |
Anaemia |
1.17 |
0.46 – 2.97 |
0.75 |
Table 3: Univariable logistic regression of potential predictor factors for AF-related rehospitalization 30 days after an acute AF / flutter admission
Univariable analysis |
|||
Parameters |
Unadjusted Hazard Ratio |
95% Confidence Interval |
p value |
Age at episode, per 1 year |
1.02 |
1.01 – 1.02 |
< 0.001 |
Age at episode ≥ 75 years |
1.43 |
1.23 – 1.67 |
< 0.001 |
Males |
0.89 |
0.76 – 1.03 |
0.11 |
Aboriginal and Torres Strait Islander |
0.89 |
0.40 – 2.00 |
0.78 |
Admission via Emergency |
1.50 |
1.26 – 1.78 |
< 0.001 |
Having ≥1 comorbidity |
1.86 |
1.43 – 2.42 |
< 0.001 |
Admitted length of stay |
1.01 |
1.00 – 1.02 |
0.005 |
Hypertension |
1.45 |
1.25 – 1.69 |
< 0.001 |
Diabetes |
1.28 |
1.08 – 1.53 |
0.006 |
Obesity |
0.99 |
0.69 – 1.41 |
0.94 |
Smoking |
0.93 |
0.78 – 1.10 |
0.38 |
Alcohol consumption |
0.51 |
0.19 – 1.36 |
0.18 |
Ischaemic heart disease |
1.37 |
1.07 – 1.74 |
0.012 |
Heart failure |
1.52 |
1.22 – 1.89 |
< 0.001 |
Stroke |
0.61 |
0.15 – 2.43 |
0.48 |
Ventricular fibrillation or tachycardia |
0.87 |
0.44 – 1.75 |
0.70 |
Chronic obstructive pulmonary disease |
1.69 |
1.31 – 2.17 |
< 0.001 |
Acute kidney failure |
1.84 |
1.39 – 2.45 |
< 0.001 |
Chronic kidney disease |
2.20 |
1.73 – 2.81 |
< 0.001 |
Mean follow-up of 2.1 ± 1.5 years to first AF-related rehospitalization or all-cause mortality or last censored date (till end of study follow-up 31 May 2019)
Table 4: Univariable Cox regression analysis of potential predictor factors for first AF-related rehospitalization or all-cause mortality after an acute AF / flutter admission
Univariable analysis |
|||
Parameters |
Unadjusted Hazard Ratio |
95% Confidence Interval |
p value |
Age at episode, per 1 year |
1.07 |
1.05 – 1.09 |
< 0.001 |
Age at episode ≥ 75 years |
3.22 |
2.24 – 4.64 |
< 0.001 |
Males |
1.07 |
0.75 – 1.54 |
0.71 |
Aboriginal and Torres Strait Islander |
0.91 |
0.13 – 6.50 |
0.92 |
Admission via Emergency |
1.68 |
1.09 – 2.59 |
0.02 |
Having ≥1comorbidity |
2.65 |
1.24 – 5.70 |
0.012 |
Length of hospital stay, days |
1.03 |
1.02 – 1.04 |
< 0.001 |
ICU stay |
5.23 |
2.30 – 11.9 |
< 0.001 |
Sepsis |
5.20 |
1.92 – 14.1 |
0.001 |
Hypertension |
2.29 |
1.59 – 3.30 |
< 0.001 |
Diabetes mellitus |
1.83 |
1.24 – 2.69 |
0.002 |
Obesity |
0.60 |
0.19 – 1.90 |
0.39 |
Smoking |
1.51 |
1.03 – 2.21 |
0.034 |
Ischaemic heart disease |
1.86 |
1.09 – 3.15 |
0.022 |
Heart failure |
4.07 |
2.75 – 6.02 |
< 0.001 |
Ventricular tachycardia or ventricular fibrillation |
3.72 |
1.52 – 9.12 |
0.004 |
Chronic obstructive pulmonary disease |
3.23 |
2.01 – 5.19 |
< 0.001 |
Acute kidney failure |
3.42 |
2.02 – 5.79 |
< 0.001 |
Chronic kidney disease |
5.53 |
3.66 – 8.37 |
< 0.001 |
Table 5: Univariable Cox regression analysis of potential predictor factors for all-cause mortality after an acute AF / flutter admission
Multivariable analysis* |
|||
Parameters |
Adjusted Odds Ratio |
95% Confidence Interval |
p value |
Age at episode, per 1 year |
1.01 |
1.00 – 1.02 |
0.17 |
Males |
1.08 |
0.73 – 1.58 |
0.71 |
Having ≥1 comorbidity |
1.53 |
0.74 – 3.16 |
0.25 |
Hypertension |
1.10 |
0.74 – 1.65 |
0.63 |
Chronic kidney disease |
1.94 |
1.07 – 3.50 |
0.028 |
Admission via Emergency |
1.52 |
0.97 – 2.38 |
0.07 |
*Multivariable logistic regression method was used to identify independent predictors of first 30 day rehospitalization after an acute AF / flutter admission.
Only variables with p<0.05 on univariable analysis were included in the multivariable analysis, except for age and gender which were included irrespective of p value.
Table 6: Independent predictors of AF-related rehospitalization 30 days after an acute AF/flutter admission
Multivariable analysis * |
|||
Parameters |
Adjusted Hazard Ratio |
95% Confidence Interval |
p value |
Age at episode, per 1 year |
1.01 |
1.01 – 1.02 |
< 0.001 |
Males |
0.99 |
0.85 – 1.16 |
0.91 |
Aboriginal and Torres Strait Islander |
1.00 |
0.45 – 2.25 |
0.99 |
Admission via Emergency |
1.29 |
1.08 – 1.54 |
0.005 |
Having ≥1 comorbidity |
1.37 |
1.04 – 1.83 |
0.03 |
Length of hospital stay, days |
1.00 |
0.99 – 1.01 |
0.99 |
Hypertension |
1.09 |
0.92 – 1.29 |
0.32 |
Diabetes mellitus |
1.06 |
0.89 – 1.28 |
0.51 |
Ischaemic heart disease |
1.03 |
0.80 – 1.34 |
0.81 |
Heart failure |
1.11 |
0.88 – 1.40 |
0.38 |
Chronic obstructive pulmonary disease |
1.41 |
1.09 – 1.83 |
0.008 |
Acute kidney failure |
1.10 |
0.79 – 1.53 |
0.56 |
Chronic kidney disease |
1.63 |
1.23 – 2.16 |
0.001 |
*Multivariable Cox proportional hazards regression method was used to identify independent predictors of first AF-related rehospitalization or all-cause mortality after an acute AF / flutter admission.
Only variables with p<0.05 on univariable analysis were included in the multivariable analysis, except for age and gender which were included irrespective of p value.
Mean follow-up of 2.1 ± 1.5 years (till end of study follow-up 31 May 2019)
Table 7: Independent predictors of first AF-related rehospitalization or all-cause mortality after an acute AF/flutter admission
Multivariable analysis * |
|||
Parameters |
Adjusted Hazard Ratio |
95% Confidence Interval |
p value |
Age at episode, per 1 year |
1.07 |
1.05 – 1.09 |
< 0.001 |
Males |
1.54 |
1.04 – 2.28 |
0.03 |
Hypertension |
1.23 |
0.83 – 1.83 |
0.30 |
Diabetes |
1.15 |
0.76 – 1.73 |
0.51 |
Heart failure |
2.03 |
1.33 – 3.10 |
0.001 |
Ischaemic heart disease |
0.78 |
0.44 – 1.39 |
0.41 |
Chronic obstructive pulmonary disease |
1.91 |
1.16 – 3.15 |
0.011 |
Acute kidney failure |
0.92 |
0.49 – 1.70 |
0.78 |
Chronic kidney disease |
2.97 |
1.79 – 4.90 |
< 0.001 |
Ventricular fibrillation or ventricular tachycardia |
2.75 |
1.10 – 6.90 |
0.031 |
Sepsis |
2.82 |
1.01 – 7.88 |
0.049 |
Smoking |
1.51 |
1.01 – 2.26 |
0.043 |
*Multivariable Cox proportional hazards regression method was used to identify independent predictors of first AF-related rehospitalization or all-cause mortality after an acute AF / flutter admission.
Only univariables with p<0.05 were included in the multivariable analysis, except for age and gender which were included irrespective of p value. Cardiac arrest, anaemia and hyperkalaemia were not included in the models
Mean follow-up of 3.0 ± 1.3 years to all-cause mortality or last censored date (till end of study follow-up 31 May 2019)
Table 8: Independent predictors of all-cause mortality after an acute AF / flutter admission
Figure 1: Kaplan-Meier survival curves for all-cause mortality or AF-related rehospitalization in patients having atleast 1 comorbidity vs patients with AF alone.
Log Rank Chi-Square 21.71, 1df, p<0.001
Figure 2: Kaplan-Meier survival curves for all-cause mortality or AF-related rehospitalization in patients with and without electrical cardioversion during index hospitalization
Log Rank Chi-Square 13.96, 1df, p<0.001
Figure 3: Kaplan-Meier survival curves for all-cause mortality or AF-related rehospitalization in patients with and without hypertension
Log Rank Chi-Square 23.18, 1df, p<0.001
Figure 4: Kaplan-Meier survival curves for all-cause mortality or AF-related rehospitalization in patients with and without chronic Kidney disease (CKD)
Log Rank Chi-Square 42.68, 1df, p<0.001
Figure 5: Kaplan-Meier survival curves for all-cause mortality or AF-related rehospitalization in patients with and without chronic obstructive pulmonary disease (COPD)
Log Rank Chi-Square 17.17, 1df, p<0.001
Tables at a glance
Figures at a glance