Clusters
The analysis resulted in 7 significant clusters, 4 in the case of patients with T2DM, and 3 in the non-diabetic patients. Dendrograms portraying patients with and without T2DM are shown in supplementary figure 1.
The resulting clusters are shown in table 1 and figure 3 (above). Clusters 1, 2, 3 and 4 pertain to patients with T2DM. Cluster number 1 (n: 201) included predominantly female patients with high cardiovascular risk without arrhythmia (only 1% had AF/flutter). They had high systolic blood pressure (SBP) and high prevalence of both dyslipidemia and atherothrombotic stroke. Cluster number 2 (n: 303) included older patients, also predominantly women, with no dyslipidemia, lower SBP, and a prevalence of AF/flutter greater than 50%. Cluster number 3 (n: 140) included mostly male patients with COPD, dyslipidemia, and liver disease. Although the presence of AF/flutter was 58.6%, this cluster showed the lowest rate of cerebrovascular disease (92.1% patients without any stroke). Cluster number 4 (n: 263) was similar to number 1. However, the prevalence of AF/flutter (93.9%), TIA (7.2%), and cardioembolic stroke (3.4%) was much higher. Clusters 5, 6 and 7 pertain to patients without T2DM. On average, these clusters portrayed older patients, with lower SBP and BMI and better eGFR than those with T2DM. Overall, the associations among the variables included are less significant (figure 2). However, variables such as hemoglobin and eGFR are more significant in defining the clusters, whereas the presence of arrhythmia is not. Cluster 5 contains predominantly men (66.5%) with COPD and a high prevalence of AF/flutter (64.8%). They also have the highest levels of eGFR (62.3 +/- 32.7ml/min, p=0.0001) and hemoglobin (12.8 +/- 2.9 gr/dl, p=0.01). Cluster 6 again contains mainly women (69.6%) with excess weight and a high prevalence of dyslipidemia (97.1%) and stroke, both hemorrhagic and cardioembolic or atherothrombotic (p=0.003). Approximately half have AF/flutter (55.1%) and of the three clusters without T2DM, patients in cluster 6 have the lowest levels of eGFR (p=0.0001) and hemoglobin (p=0.01). Finally, cluster 7, with a 67% predominance of women, is quite undifferentiated, with a slightly higher SBP than the other clusters without T2DM, and a notable prevalence of AF/flutter (63.2%) and TIA (4%).
Some additional findings by clusters are shown in Table 2. Patients with T2DM had more history of hypertension, mainly clusters 3 and 4. Charlson comorbidity index is similarly higher in these patients, the highest levels being found in cluster 3. Regarding etiology of HF, ischemic cardiomyopathy was significantly prevalent in patients with T2DM (p=0.001), particularly in cluster 3 (40%). Finally, significant differences in treatment were detected among the clusters. Overall, patients with T2DM were more often treated with angiotensin-converting enzyme inhibitors (ACEi)/angiotensin receptor blockers (ARB) (p=0.004), beta-blockers (p=0.003), loop diuretics (p=0.007), and thiazides (p=0.009).