Epidemiology of Arrhythmias and Conduction Disorders in Older Adults

Androgen deprivation therapy (ADT) has been associated with coronary heart disease and myocardial infarction (MI) in prostate cancer patients, but controversy persists regarding its effects on cardiovascular mortality (CVM).

We assessed the long-term relationship between ADT and CVM in a prostate cancer randomized trial (NRG Oncology/Radiation Therapy Oncology Group 9202).

From 1992 to 1995, 1554 men with locally advanced prostate cancer (T2c–T4, prostate-specific antigen <150 ng/ml) received radiotherapy with 4 mo (short-term [STADT]) versus 28 mo (longer-term [LTADT]) of ADT.

Using the Fine-Gray and Cox regression models, the relationship between ADT and mortality was evaluated.

With a median follow-up of 19.6 yr, LTADT was associated with improved overall survival (OS) versus STADT (adjusted hazard ratio [HR] 0.88; p = 0.03) and prostate cancer survival (subdistribution HR [sHR] 0.70, p = 0.003). Comparing LTADT with STADT, prostate cancer mortality improved by 6.0% (15.6% [95% confidence interval 13.0–18.3%] vs 21.6% [18.6–24.7%]) at 15 yr, while CVM increased by 2.2% (14.9% [12.4–17.6%] vs 12.7% [10.4–15.3%]). In multivariable analyses, LTADT was not associated with increased CVM versus STADT (sHR 1.22 [0.93–1.59]; p = 0.15). An association between LTADT and MI death was detected (sHR 1.58 [1.00–2.50]; p = 0.05), particularly in patients with prevalent cardiovascular disease (CVD; sHR 2.54 [1.16–5.58]; p = 0.02).

With 19.6 yr of follow-up, LTADT was not significantly associated with increased CVM in men with locally advanced prostate cancer. Patients may have increased MI mortality with LTADT, particularly those with baseline CVD. Overall, there remained a prostate cancer mortality benefit and no OS detriment with LTADT.

In a long-term analysis of a large randomized prostate cancer trial, radiation with 28 mo of hormone therapy did not increase the risk of cardiovascular death significantly versus 4 mo of hormone therapy. Future studies are needed for patients with pre-existing heart disease, who may have an increased risk of myocardial infarction death with longer hormone use.

Past research based on observations has suggested that the gut microbiome (GM) could play a role in developing arrhythmias and conduction blocks. Nonetheless, the nature of this association remains uncertain due to the potential for reverse causation and confounding factors in observational research. The aim of this investigation is to elucidate the causal relationship between GM and the development of arrhythmias as well as conduction blocks.

This study collected summary statistics regarding GM, arrhythmias, and conduction blocks. Two-sample Mendelian randomization (MR) analysis was carried out employing various methods, with inverse variance weighted being the primary approach, followed by weighted median, simple mode, MR-Egger, and MR-PRESSO. Moreover, the MR findings were corroborated through multiple sensitivity analyses.

Among them, for atrial fibrillation and flutter (AF), phylum_Actinobacteria and genus_RuminococcaceaeUCG004 demonstrated a negative correlation, while order_Pasteurellales, family_Pasteurellaceae, and genus_Turicibacter were associated with an increased risk. In the case of paroxysmal tachycardia (PT), genus_Holdemania and genus_Roseburia were found to reduce risk. For atrioventricular block (AVB), order_Bifidobacteriales, family_Bifidobacteriaceae, and genus_Alistipes exhibited a negative correlation, whereas genus_CandidatusSoleaferrea showed a positive correlation. Concerning the left bundle-branch block (LBBB), family_Peptococcaceae appeared to decrease the risk, while genus_Flavonifractor was linked to an increased risk. Lastly, no causative GM was identified in the right bundle-branch block (RBBB) context.

We have uncovered potential causal links between some GM, arrhythmias, and conduction blocks. This insight may aid in designing microbiome-based interventions for these conditions and their risk factors in future trials. Additionally, it could facilitate the discovery of novel biomarkers for targeted prevention strategies.

Diffuse large B-cell lymphoma (DLBCL) patients have been reported to have cardiac manifestations, however, arrhythmias have not been characterized in this population. We examined the predictors of arrhythmias and assessed the impact of arrhythmias on inpatient outcomes among DLBCL patients.

Retrospective cohort analysis was performed using the National Inpatient Sample data collected between 2016 and 2018. Multivariable logistic and linear regression models were used to examine the predictors of arrhythmias and inpatient outcomes among DLBCL patients.

11% of DLBCL patients had a diagnosis of arrhythmias. Patients aged 70 years or older had 2.6 times higher odds (95% CI: 2.37–2.78) of having arrhythmias compared to patients younger than 70 years. Females were 23% (AOR: 0.77; 95% CI: 0.71–0.83) less likely to have a diagnosis of arrhythmias relative to their male counterparts. Compared to non-Hispanic whites, patients who were non-Hispanic blacks (AOR: 0.69; 95% CI: 0.60–0.81), Hispanics (AOR: 0.60; 95% CI: 0.52–0.69) or in the non-Hispanic other category (AOR: 0.80; 95% CI: 0.70–0.91) were significantly less likely to be diagnosed with arrhythmias. Other factors that predicted arrhythmias were patient disposition and comorbidity index. Additionally, arrhythmias were associated with higher inpatient mortality, length of stay and hospital costs.

Older male patients were more likely to be diagnosed with arrhythmias while non-Hispanic blacks and Hispanics were less likely to have arrhythmias. These findings highlight the need for surveillance to enable early detection of arrhythmias in this population.

Life expectancy is increasing due to developments in socioeconomic conditions and medicine. However, cardiovascular diseases, which are the most common cause of death in the geriatric population, appear more frequently and in a complex manner, especially in developed countries. Since many age-related cardiovascular and cerebrovascular diseases gradually increase their effects due to changes in arterial function, today it is of great importance to determine the mechanisms of arterial aging and to take precautions. Although it is well known that diabetes, hyperlipidemia, sedentary lifestyle, and genetic factors can cause a range of cardiovascular diseases such as hypertension, coronary artery disease, and cerebrovascular cases, it is also a fact that aging is indisputably the biggest risk factor for vascular diseases. This chapter discusses the pathophysiological mechanisms affecting cardiovascular aging and their interrelationships.