Reduction in Heart Rate Variability in Autosomal Dominant Polycystic Kidney Disease

The Effect of Caffeine on Heart Rate Variability in Newborns: A Pilot Study

Neonatal apnoea can be treated with caffeine, which affects the central nervous and cardiovascular systems. Heart rate variability (HRV) reflects the activity of the autonomic nervous system (ANS) and might be used as a measure of ANS maturation in newborns. We aimed to establish the effect of caffeine on HRV in newborns and investigated the potential correlation between HRV and postmenstrual age (PMA). In 25 haemodynamically stable newborns hospitalized due to apnoea and treated with caffeine (2.5 mg/kg), we assessed breathing frequency, arterial oxygen saturation, body temperature, and the heart rate while they were sleeping. We assessed HRV by spectral analysis using fast Fourier transformation. The same protocol was reapplied 100 h after caffeine withdrawal to assess the control parameters. Caffeine increased breathing frequency (p = 0.023) but did not affect any other parameter assessed including HRV. We established a positive correlation between postmenstrual age and HRV during treatment with caffeine as well as after caffeine had been withdrawn (total power: p = 0.044; low-frequency band: p = 0.039). Apparently, the maintenance dose of caffeine is too low to affect the heart rate and HRV. A positive correlation between PMA and HRV might reflect maturation of the ANS, irrespective of caffeine treatment.

Autonomic cardiac modulation in postmenopausal women with dry eye syndrome: a cross-sectional analytical study

OBJECTIVE

The aim of this study was to assess cardiac autonomic modulation in postmenopausal women with and without dry eye syndrome (DES) and to identify associations between clinical and socioeconomic factors.

METHODS

A cross-sectional study was carried out at the Institute of Ocular Surgery of the Northeast (ICONE), Brazil. Convenience sample of postmenopausal women, over 40 years old, who were divided into two groups: with and without DES. Clinical, sociodemographic, and ophthalmological characteristics of these women were assessed. Capture of RR intervals was performed using a cardio frequency meter. Differences between the groups were analyzed using the Chi-square test, the Student's t test, and the Mann-Whitney test.

RESULTS

Women with DES were present in 60.4% (n=58), highest median age (63.5 years, 95%CI 62.0-67.9; p<0.001), median length of time menopause (19 years old, 95%CI 10.4-24.0; p<0.001). There was a difference in the standard deviation of all normal-to-normal index between the groups. However, when the differences were adjusted to the clinical model, no association was found between DES and heart rate variability (HRV).

CONCLUSIONS

The analysis of cardiac autonomic modulation in postmenopausal women is similar in the presence or absence of DES. Clinical factors, time of menopause, and intensity of symptoms were not associated with HRV indices.

Cardiovascular Risk and Quality of Life in Autosomal Dominant Polycystic Kidney Disease Patients on Therapy With Tolvaptan: A Pilot Study

INTRODUCTION

Cardiovascular (CV) complications are the most frequent cause of morbidity and mortality in autosomal dominant polycystic kidney disease (ADPKD) patients. In 2017, the Italian Medicines Agency authorised tolvaptan, a vasopressin V2 receptor antagonist, for the treatment of ADPKD, based on the Tolvaptan Phase 3 Efficacy and Safety Study in ADPKD (TEMPO 3: 4), TEMPO 4: 4 and Replicating Evidence of Preserved Renal Function: An Investigation of Tolvaptan Safety and Efficacy (REPRISE) studies.

AIM OF THE STUDY

The aim of the study was to assess the impact of tolvaptan on CV risk and quality of life, evaluated by nutritional, inflammatory, metabolic, instrumental parameters and psychocognitive tests on ADPKD patients.

METHODS AND MATERIALS

We evaluated 36 patients with ADPKD; 10 patients (7 males, mean age 42.5±7.0 years) treated with tolvaptan and 26 controls (11 males, mean age 36.7±9.1 years). They underwent, at T0, monthly, and at T1 (1 year) clinical, laboratory and instrumental evaluation, in addition to psychocognitive tests.

RESULTS

In ADPKD patients treated with tolvaptan, we found at T1, a decrease in carotid intima-- media thickness (p=0.048), epicardial adipose tissue thickness (p=0.002), C-reactive protein (p=0.026), sympathovagal balance during night (p=0.045) and increased flow-mediated dilation (p=0.023) with a reduction in depression (Hamilton and Beck tests, p=0.008 and p=0.002, respectively) compared with controls.

CONCLUSION

These preliminary results suggest that treatment with tolvaptan could improve early atherosclerosis and endothelial dysfunction markers and improve mood in ADPKD patients (probably by acting on endothelial cell and adipocyte V2 receptors).