Effects of sildenafil and vardenafil treatments on sleep quality and depression in hemodialysis patients with erectile dysfunction

Exploring the Multifaceted Potential of Sildenafil in Medicine

Phosphodiesterase type 5 (PDE5) is pivotal in cellular signalling, regulating cyclic guanosine monophosphate (cGMP) levels crucial for smooth muscle relaxation and vasodilation. By targeting cGMP for degradation, PDE5 inhibits sustained vasodilation. PDE5 operates in diverse anatomical regions, with its upregulation linked to various pathologies, including cancer and neurodegenerative diseases. Sildenafil, a selective PDE5 inhibitor, is prescribed for erectile dysfunction and pulmonary arterial hypertension. However, considering the extensive roles of PDE5, sildenafil might be useful in other pathologies. This review aims to comprehensively explore sildenafil's therapeutic potential across medicine, addressing a gap in the current literature. Recognising sildenafil's broader potential may unveil new treatment avenues, optimising existing approaches and broadening its clinical application.

Phosphodiesterase inhibitors in psychiatric disorders

RATIONALE

Challenges in drug development for psychiatric disorders have left much room for the introduction of novel treatments with better therapeutic efficacies and indices. As a result, intense research has focused on identifying new targets for developing such pharmacotherapies. One of these targets may be the phosphodiesterase (PDE) class of enzymes, which play important roles in intracellular signaling. Due to their critical roles in cellular pathways, these enzymes affect diverse neurobiological functions from learning and memory formation to neuroinflammation.

OBJECTIVES

In this paper, we reviewed studies on the use of PDE inhibitors (PDEIs) in preclinical models and clinical trials of psychiatric disorders including depression, anxiety, schizophrenia, post-traumatic stress disorder (PTSD), bipolar disorder (BP), sexual dysfunction, and feeding disorders.

RESULTS

PDEIs are able to improve symptoms of psychiatric disorders in preclinical models through activating the cAMP-PKA-CREB and cGMP-PKG pathways, attenuating neuroinflammation and oxidative stress, and stimulating neural plasticity. The most promising therapeutic candidates to emerge from these preclinical studies are PDE2 and PDE4 inhibitors for depression and anxiety and PDE1 and PDE10 inhibitors for schizophrenia. Furthermore, PDE3 and 4 inhibitors have shown promising results in clinical trials in patients with depression and schizophrenia.

CONCLUSIONS

Larger and better designed clinical studies of PDEIs in schizophrenia, depression, and anxiety are warranted to facilitate their translation into the clinic. Regarding the other conditions discussed in this review (most notably PTSD and BP), better characterization of the effects of PDEIs in preclinical models is required before clinical studies.

Vardenafil in the Treatment of Male Erectile Dysfunction: A Systematic Review and Meta-Analysis

INTRODUCTION

We carried out this systemic review and meta-analysis of relevant randomized controlled trials to determine different dosage regimens of vardenafil in the treatment of male erectile dysfunction (ED).

METHODS

Using appropriate keywords, we searched PubMed, the Cochrane Library, and Embase for relevant literature before March 2020. We evaluated odds ratio (OR), weighted mean difference (WMD), and 95% confidence interval (95% CI) to assess the results of each study.

RESULTS

We included 14 studies with a total of 3221 patients. Compared with the placebo, vardenafil significantly increased International Erectile Function Index (IIEF) overall satisfaction (WMD 3.37, 95% CI 2.02-4.71), IIEF-erectile function (WMD 7.93, 95% CI 6.00-9.85), IIEF sexual desire (WMD 0.79, 95% CI 0.24-1.35), IIEF intercourse satisfaction (WMD 5.24, 95% CI 3.35-7.13), IIEF orgasmic function (WMD 3.81, 95% CI 2.26-5.35), Sexual Encounter Profile (SEP) Q2 (WMD 26.36, 95% CI 22.95-29.77), and SEP Q3 (WMD 35.18, 95% CI 31.89-38.48).

CONCLUSIONS

Vardenafil demonstrated significant efficacy in the treatment of ED, but the optimal dose and course of vardenafil remain to be established.

Resistance training improves sleep quality, redox balance and inflammatory profile in maintenance hemodialysis patients: a randomized controlled trial

Patients in maintenance hemodialisys (HD) present sleep disorders, increased inflammation, unbalanced redox profiles, and elevated biomarkers representing endothelial dysfunction. Resistance training (RT) has shown to mitigate the loss of muscle mass, strength, improve inflammatory profiles, and endothelial function while decreasing oxidative stress for those in HD. However, the relation between those factors and sleep quality are inadequately described. The aim of this study was to verify the effects of 3 months of RT on sleep quality, redox balance, nitric oxide (NO) bioavailability, inflammation profile, and asymmetric dimethylarginine (ADMA) in patients undergoing HD. Our primary goal was to describe the role of RT on sleep quality. Our secondary goal was to evaluate the effect of RT on NO, metabolism markers, and inflammatory and redox profiles as potential mechanisms to explain RT-induced sleep quality changes. Fifty-five men undergoing maintenance hemodialysis were randomized into either a control (CTL, n = 25) and RT group (RTG; n = 30). Participants in the RT group demonstrated an improvement in sleep pattern, redox, inflammatory profiles, and biomarkers of endothelial function (NO₂^- and ADMA). This group also increased muscle strength (total workload in RT exercises of upper and lower limbs). These findings support that RT may improve the clinical status of HD patients by improving their sleep quality, oxidative and inflammatory parameters.

Interventions for improving sleep quality in people with chronic kidney disease

BACKGROUND

Sleep disorders are commonly experienced by people with chronic kidney disease (CKD). Several approaches for improving sleep quality are used in clinical practice including relaxation techniques, exercise, acupressure, and medication.

OBJECTIVES

To assess the effectiveness and associated adverse events of interventions designed to improve sleep quality among adults and children with CKD including people with end-stage kidney disease (ESKD) treated with dialysis or kidney transplantation.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 8 October 2018 with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) or quasi-randomised RCTs of any intervention in which investigators reported effects on sleep quality. Two authors independently screened titles and abstracts of identified records.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed the risk of bias for included studies. The primary outcomes were sleep quality, sleep onset latency, sleep duration, sleep interruption, and sleep efficiency. Risks of bias were assessed using the Cochrane tool. Evidence certainty was assessed using the GRADE approach. We calculated treatment estimates as risk ratios (RR) for dichotomous outcomes or mean difference (MD) or standardised MD (SMD) for continuous outcomes to account for heterogeneity in measures of sleep quality.

MAIN RESULTS

Sixty-seven studies involving 3427 participants met the eligibility criteria. Thirty-six studies involving 2239 participants were included in meta-analyses. Follow-up for clinical outcomes ranged between 0.3 and 52.8 weeks (median 5 weeks). Interventions included relaxation techniques, exercise, acupressure, cognitive-behavioural therapy (CBT), educational interventions, benzodiazepine treatment, dopaminergic agonists, telephone support, melatonin, reflexology, light therapy, different forms of peritoneal dialysis, music, aromatherapy, and massage. Incomplete reporting of key methodological details resulted in uncertain risk of bias in many studies.In very low certainty evidence relaxation techniques had uncertain effects on sleep quality and duration, health-related quality of life (HRQoL), depression, anxiety, and fatigue. Studies were not designed to evaluate the effects of relaxation on sleep latency or hospitalisation. Exercise had uncertain effects on sleep quality (SMD -1.10, 95% CI -2.26 to 0.05; I2 = 90%; 5 studies, 165 participants; very low certainty evidence). Exercise probably decreased depression (MD -9.05, 95% CI -13.72 to -4.39; I2 = 0%; 2 studies, 46 participants; moderate certainty evidence) and fatigue (SMD -0.68, 95% CI -1.07 to -0.29; I2 = 0%; 2 studies, 107 participants; moderate certainty evidence). Compared with no acupressure, acupressure had uncertain effects on sleep quality (Pittsburgh Sleep Quality Index (PSQI) scale 0 - 21) (MD -1.27, 95% CI -2.13 to -0.40; I2 = 89%; 6 studies, 367 participants: very low certainty evidence). Acupressure probably slightly improved sleep latency (scale 0 - 3) (MD -0.59, 95% CI -0.92 to -0.27; I2 = 0%; 3 studies, 173 participants; moderate certainty evidence) and sleep time (scale 0 - 3) (MD -0.60, 95% CI -1.12 to -0.09; I2 = 68%; 3 studies, 173 participants; moderate certainty evidence), although effects on sleep disturbance were uncertain as the evidence certainty was very low (scale 0 - 3) (MD -0.49, 95% CI -1.16 to 0.19; I2 = 97%). In moderate certainty evidence, acupressure probably decrease fatigue (MD -1.07, 95% CI -1.67 to -0.48; I2 = 0%; 2 studies, 137 participants). Acupressure had uncertain effects on depression (MD -3.65, 95% CI -7.63 to 0.33; I2 = 27%; 2 studies, 137 participants; very low certainty evidence) while studies were not designed to evaluate the effect of acupressure on HRQoL, anxiety, or hospitalisation. It was uncertain whether acupressure compared with sham acupressure improved sleep quality (PSQI scale 0 to 21) because the certainty of the evidence was very low (MD -2.25, 95% CI -6.33 to 1.82; I2 = 96%; 2 studies, 129 participants), but total sleep time may have been improved (SMD -0.34, 95% CI -0.73 to 0.04; I2 = 0%; 2 studies, 107 participants; low certainty evidence). 2 =2 =There were no studies designed to directly examine and/or correlate efficacy of any interventions aimed at improving sleep that may have been attempted for the spectrum of sleep disordered breathing. No studies reported treatment effects for children. Adverse effects of therapies were very uncertain.

AUTHORS' CONCLUSIONS

The evidence base for improving sleep quality and related outcomes for adults and children with CKD is sparse. Relaxation techniques and exercise had uncertain effects on sleep outcomes. Acupressure may improve sleep latency and duration, although these findings are based on few studies. The effects of acupressure were not confirmed in studies in which sham acupressure was used as the control. Given the very low certainly evidence, future research will very likely change the evidence base. Based on the importance of symptom management to patients, caregivers and clinicians, future studies of sleep interventions among people with CKD should be a priority.

Proconvulsant effects of sildenafil citrate on pilocarpine-induced seizures: Involvement of cholinergic, nitrergic and pro-oxidant mechanisms

Sildenafil is a phosphodiesterase 5 inhibitor used for the treatment of erectile dysfunction and pulmonary hypertension. Proconvulsant effect is a serious adverse event associated with sildenafil use. Here, we investigated the possible proconvulsant effects of sildenafil in pilocarpine (PILO)-induced seizures model, which mimics some aspects of temporal lobe epilepsy. We also evaluated sildenafil's effects on hippocampal markers related to PILO-induced seizure, for instance, acetylcholinesterase (AChE) activity, oxidative stress and nitric oxide (NO) markers, namely nitrite, inducible NO synthase (iNOS) and neuronal NOS (nNOS). The influences of muscarinic receptors blockade on sildenafil proconvulsant effects and brain nitrite levels were also evaluated. Male mice were submitted to single or repeated (7 days) sildenafil administration (2.5, 5, 10 and 20 mg/kg). Thirty minutes later, PILO was injected and mice were further evaluated for 1 h for seizure activity. Sildenafil induced a dose- and time-progressive proconvulsant effect in PILO-induced seizures. Sildenafil also potentiated the inhibitory effect of PILO in AChE activity and induced a further increase in nitrite levels and pro-oxidative markers, mainly in the hippocampus. Repeated sildenafil treatment also increased the hippocampal expression of iNOS and nNOS isoforms, while the blockade of muscarinic receptors attenuated both sildenafil-induced proconvulsant effect and brain nitrite changes. Our data firstly demonstrated the proconvulsant effect of sildenafil in PILO-model of seizures. This effect seems to be related to an increased cholinergic-nitrergic tone and pro-oxidative brain changes. Also, our findings advert to caution in using sildenafil for patients suffering from neurological conditions that reduces seizure threshold, such as epilepsy.

Gonadal dysfunction in chronic kidney disease

Sexual dysfunction is a common finding in both men and women with chronic kidney failure. Common disturbances include erectile dysfunction in men, menstrual abnormalities in women, and decreased libido and fertility in both sexes. These abnormalities are primarily organic in nature and are related to uremia as well as the other comorbid conditions that frequently occur in the chronic kidney failure patient. Fatigue and psycho social factors related to the presence of a chronic disease are also contributory factors. Disturbances in the hypothalamic-pituitary-gonadal axis can be detected prior to the need for dialysis but continue to worsen once dialytic therapy is initiated. Impaired gonadal function is prominent in uremic men while the disturbances in the hypothalamic-pituitary axis are more subtle. By contrast, central disturbances are more prominent in uremic women. Therapy is initially directed towards optimizing the delivery of dialysis, correcting anemia with recombinant erythropoietin, and controlling the degree of secondary hyperparathyroidism with vitamin D. For many practicing nephrologists sildenafil has become the first line therapy in the treatment of impotence. In the hypogonadal man whose only complaint is decreased libido, testosterone may be of benefit. Regular gynecologic follow up is required in uremic women to guard against potential complications of unopposed estrogen effect. Uremic women should be advised against pregnancy while on dialysis. Successful transplantation is the most effective means of restoring normal sexual function in both men and women with chronic kidney failure.

The effect of foot reflexology and back massage on hemodialysis patients' fatigue and sleep quality

OBJECTIVE

The aim of this study is to examine the effectiveness of foot reflexology and back massage on optimizing the sleep quality and reducing the fatigue of hemodialysis patients.

METHODS

The study includes 105 volunteer patients who were registered at a private dialysis clinic and were receiving hemodialysis treatment. Foot reflexology and back massage were administered to the patients two times a week for four weeks. The Visual Analogue Scale for Fatigue and the Pittsburg Sleep Quality Index were used to collect data.

RESULTS

The differences between the pretest and posttest score averages of the patients on the Visual Analogue Scale for Fatigue and the Pittsburg Sleep Quality Index were statistically significant (p < 0.001).

CONCLUSION

Foot reflexology and back massage were shown to improve the sleep quality and reduce the fatigue of hemodialysis patients. Compared to back massage, foot reflexology was determined to be more effective.

Antidepressants for treating depression in adults with end-stage kidney disease treated with dialysis

BACKGROUND

Depression affects approximately one-quarter of people treated with dialysis and is considered an important research uncertainty by patients and health professionals. Treatment for depression in dialysis patients may have different benefits and harms compared to the general population due to different clearances of antidepressant medication and the severity of somatic symptoms associated with end-stage kidney disease (ESKD). Guidelines suggest treatment of depression in dialysis patients with pharmacological therapy, preferably a selective serotonin reuptake inhibitor. This is an update of a review first published in 2005.

OBJECTIVES

To evaluate the benefit and harms of antidepressants for treating depression in adults with ESKD treated with dialysis.

SEARCH METHODS

We searched Cochrane Kidney and Transplant's Specialised Register to 20 January 2016 through contact with the Information Specialist using search terms relevant to this review.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing antidepressant treatment with placebo or no treatment, or compared to another antidepressant medication or psychological intervention in adults with ESKD (estimated glomerular filtration rate < 15 mL/min/1.73 m(2)).

DATA COLLECTION AND ANALYSIS

Data were abstracted by two authors independently onto a standard form and subsequently entered into Review Manager. Risk ratios (RR) for dichotomous data and mean differences (MD) for continuous data were calculated with 95% confidence intervals (95% CI).

MAIN RESULTS

Four studies in 170 participants compared antidepressant therapy (fluoxetine, sertraline, citalopram or escitalopram) versus placebo or psychological training for 8 to 12 weeks. In generally very low or ungradeable evidence, compared to placebo, antidepressant therapy had no evidence of benefit on quality of life, had uncertain effects on increasing the risk of hypotension (3 studies, 144 participants: RR 1.72, 95% CI 0.75 to 3.92), headache (2 studies 56 participants: RR 2.91, 95% CI 0.73 to 11.57), and sexual dysfunction (2 studies, 101 participants: RR 3.83, 95% CI 0.63 to 23.34), and increased nausea (3 studies, 114 participants: RR 2.67, 95% CI 1.26 to 5.68). There were few or no data for hospitalisation, suicide or all-cause mortality resulting in inconclusive evidence. Antidepressant therapy may reduce depression scores during treatment compared to placebo (1 study, 43 participants: MD -7.50, 95% CI -11.94 to -3.06). Antidepressant therapy was not statistically different from group psychological therapy for effects on depression scores or withdrawal from treatment and a range of other outcomes were not measured.

AUTHORS' CONCLUSIONS

Despite the high prevalence of depression in dialysis patients and the relative priority that patients place on effective treatments, evidence for antidepressant medication in the dialysis setting is sparse and data are generally inconclusive. The relative benefits and harms of antidepressant therapy in dialysis patients are poorly known and large randomised studies of antidepressants versus placebo are required.