The effects of dialysis modality choice on cognitive functions in patients with end-stage renal failure: a systematic review and meta-analysis

Analysis of the trajectory of cognitive function changes and influencing factors in maintenance hemodialysis patients: a prospective longitudinal study

OBJECTIVES

To explore the trajectory of cognitive function changes and influencing factors in maintenance hemodialysis (MHD) patients.

METHODS

A convenience sampling method was used to select MHD patients from a tertiary hospital in Chengdu from August 2023 to April 2024. The general information questionnaire, Chinese version of the Montreal Cognitive Assessment (MoCA), Pittsburgh Sleep Quality Index (PSQI), Appetite Visual Analogue Scale (VAS), and Family Care Index (APGAR) were used for the investigation. Patients' cognitive function levels were assessed at baseline and at 3, 6, and 9 months after the initial survey. A latent growth model was used to identify potential categories of cognitive function trajectory, and univariate and binary logistic regression analyses were performed to analyze the influencing factors.

RESULTS

A total of 154 MHD patients completed the entire study. The trajectory of cognitive function changes was divided into two potential categories: low cognitive function-fast decline group and high cognitive function-slow decline group. Binary logistic regression results showed that educational level, hypertension, sleep quality, appetite, and family care were influencing factors for the trajectory of cognitive function changes in MHD patients.

CONCLUSIONS

Cognitive function in MHD patients showed an overall declining trend over time. The cognitive function change trajectory could be divided into two potential categories: fast decline group and high cognitive function-slow decline group. Healthcare professionals can develop targeted nursing intervention programs based on the characteristics of different patient types and their influencing factors to improve cognitive function and enhance quality of life.

Dialysis and cognitive impairment

People with chronic kidney disease who require maintenance dialysis characteristically experience accelerated and aggravated cognitive decline compared with those with advanced kidney disease who are not receiving this form of kidney replacement therapy. This effect is inadequately appreciated, but of crucial importance to patients, their carers and the health-care systems that support them. Although many of the comorbid conditions prevalent in this patient population have the potential to affect brain structure and function, an evolving body of evidence indicates that the dialysis therapy itself has a central role in the pathophysiology of progressive cognitive impairment. Both haemodialysis and peritoneal dialysis are associated with structural and functional changes in the brain that can lead to characteristic short-term symptoms, such as headache, confusion, delirium and brain fog, as well as long-term reductions in cognitive functional ability. Here, we explore the mechanisms, both established and putative, underlying these effects and consider approaches to addressing this issue with both single and complex therapeutic interventions.

Nutrition, cognition and chronic kidney disease: A comprehensive review of interactions and interventions

BACKGROUND

Cognitive impairment is a prevalent complication in chronic kidney disease (CKD), ranging from mild deficits in early stages to more severe conditions, such as mild cognitive impairment and dementia in advanced stages. CKD patients exhibit reduced performance in memory, attention, language, visuospatial abilities and executive functions.

RESULTS AND DISCUSSION

Contributing factors include uraemic toxins, structural brain changes, blood-brain barrier dysfunction, anaemia and comorbidities like diabetes mellitus. Malnutrition, affecting nearly half of CKD patients, exacerbates cognitive decline through inflammation, oxidative stress and protein-energy wasting. Nutritional deficiencies, particularly in protein, vitamin D, B vitamins, omega-3 fatty acids and antioxidants, are linked to impaired cognition. Emerging evidence highlights the role of the gut-brain axis, with gut-derived uraemic toxins and microbiome alterations contributing to cognitive dysfunction. Processed foods and microplastics further compound risks by promoting inflammation and neurotoxicity. Dialysis and kidney transplantation offer opportunities for cognitive recovery, though challenges remain, particularly in haemodialysis patients. Nutritional interventions, including tailored protein intake, micronutrient supplementation and dietary counselling, are critical for mitigating cognitive decline. Addressing CKD comorbidities, such as anaemia and diabetes through targeted nutritional and pharmacological strategies, improves outcomes. Integrating psychological and social support enhances quality of life, given the high prevalence of anxiety and depression in CKD patients.

CONCLUSIONS

Future research should focus on personalized nutrition, gut microbiota modulation and routine cognitive assessments to optimise care. A holistic approach combining medical, nutritional and psychosocial strategies is essential for improving cognitive and overall health in CKD patients.

Care pathways for patients with cognitive impairment and chronic kidney disease

Various epidemiological datasets and pathophysiological hypotheses have highlighted a significant link between chronic kidney disease (CKD) and cognitive impairment (CI); each condition can potentially exacerbate the other. Here, we review the mutual consequences of CKD and CI on health outcomes and care pathways and highlight the complexities due to the involvement of different specialists. Our narrative review covers (i) the burden of CI among patients with CKD, (ii) the impact of CI on kidney health, (iii) access to kidney replacement therapy for people with CI, (iv) resources in cognitive care and (v) potential models for integrated 'nephro-cognitive' care. CI (ranging from mild CI to dementia) has a significant impact on older adults, with a high prevalence and a strong association with CKD. Furthermore, CI complicates the management of CKD and leads to a higher mortality rate, poorer quality of life and higher healthcare costs. Due to difficulties in symptom description and poor adherence to medical guidelines, the presence of CI can delay the treatment of CKD. Access to care for patients with both CKD and CI is hindered by physical, cognitive and systemic barriers, resulting in less intensive, less timely care. Multidisciplinary approaches involving nephrologists, geriatricians, neurologists and other specialists are crucial. Integrated care models focused on person-centred approaches, shared decision-making and continuous co-management may improve outcomes. Future research should focus on the putative beneficial effects of these various strategies on both clinical and patient-reported outcomes.

Combining hemodialysis with peritoneal dialysis improves cognitive function: a three-case report

Chronic kidney disease (CKD) is associated with multiple complications, with recent scholarly attention underscoring cognitive impairment as a salient manifestation. Considering societal aging, preserving cognitive function has emerged as an urgent medical concern. Prolonged dialysis, encompassing hemodialysis (HD) and peritoneal dialysis (PD), has been associated with a decline in cognitive function. Here, we present the cases of three patients undergoing PD who exhibited a noticeable improvement in cognitive function upon the initiation of HD. One patient had exhibited mild cognitive decline, whereas the remaining two presented more severe impairment. Apart from a mild tendency for fluid retention, none of the three patients exhibited abnormalities in physical or imaging examinations. Evaluation using the Japanese version of the Montreal Cognitive Assessment (MoCA-J) yielded decreased scores across multiple domains, notably in executive and attention functions. However, after HD initiation, all patients demonstrated a marked enhancement in multiple MoCA-J parameters, accompanied by a significant improvement in subjective symptoms. Moreover, improvements in anemia and hypoalbuminemia were observed in all three patients, whereas consistent trends in other parameters were absent. These clinical observations suggest that the integration of HD into the therapeutic regimen of patients undergoing PD may enhance cognitive function, highlighting the contributory roles of hemoglobin and albumin in CKD-associated cognitive impairment.

Does Dialysis Therapy Cause Cognitive Impairment in Older Adults? A Propensity Score Matching Retrospective Study From a Japanese Long-Term Care Insurance Certification Survey

This study explored the longitudinal connection between dialysis therapy in older adults and the incidence of cognitive impairment, and trends of general abilities. We conducted a retrospective propensity score matching (PSM) analysis of data from the care-needs certification survey in City A, Japan, spanning 2017 to 2021. Our sample comprised 11 443 initially cognitively intact older adults from the baseline year 2017. Among them, individuals had received dialysis therapy at baseline, and 216 individuals were included after PSM. The dialysis group had a significantly lower incidence of cognitive impairment during follow-up than the control group (P = 0.02). The competing risk of death was significantly higher in the dialysis group than in the control group (P < .001). Both groups showed a decline in their comprehensive ability over the time. There have been several reports of a negative association between dialysis and cognitive impairment, but more detailed investigation of the longitudinal relationship may be needed. Comprehensive support remains critical for both dialysis and non-dialysis older adults.

Treatment of chronic kidney disease in older populations

As the world population ages, an expected increase in the prevalence of chronic kidney disease (CKD) among older individuals will pose a considerable challenge for health care systems in terms of resource allocation for disease management. Treatment strategies for older patients with CKD should ideally align with those applied to the general population, focusing on minimizing cardiovascular events and reducing the risk of progression to kidney failure. Emerging therapies, such as SGLT-2 inhibitors and GLP-1 receptor agonists, hold promise for the effective management of CKD in older individuals. In addition, non-pharmacological interventions such as nutritional and exercise therapies have a crucial role. These interventions enhance the effects of pharmacotherapy and, importantly, contribute to the maintenance of cognitive function and overall quality of life. Various factors beyond age and cognitive function must be taken into account when considering kidney replacement therapy for patients with kidney failure. Importantly, all treatment options, including dialysis, transplantation and conservative management approaches, should be tailored to the individual through patient-centred decision-making. The dynamic integration of digital technologies into medical practice has the potential to transform the management of CKD in the aging population.

Cognitive Dysfunction Screening in Peritoneal Dialysis Patients: A Cross-Sectional Study

Background

Mild cognitive impairment (MCI) in peritoneal dialysis (PD) patients has been described as a risk factor for worse outcomes such as peritonitis, technique failure, and mortality. In this study, we aimed to determine the prevalence of MCI in a population of PD patients and identify the possible risk factors associated with MCI.

Materials and Methods

We performed an observational, cross-sectional study to evaluate cognitive function using the Montreal Cognitive Assessment (MOCA) test and the Mini Mental State Examination (MMSE) test in PD patients. Patients with diagnosis of dementia or severe neurologic impairment, active cancer, or infection were excluded.

Results

We evaluated 66 patients (mean age 60 years); 53% were male. Prevalence of MCI assessed by MOCA test and MMSE test was 65% and 33%, respectively. Predictors of MCI with MOCA test were higher age (P = 0.0001), lower education level (P = 0.005), need of a helper (P = 0.009), and continuous ambulatory PD modality (P = 0.019). Higher Charlson comorbidity index (P = 0.002), coronary artery disease (P = 0.006), and peripheral artery disease (P = 0.033) were also associated with MCI. Lower Kt/V (P = 0.012) and lower levels of normalized protein catabolic rate (nPCR; P < 0.000) were related to MCI. MCI patients had more episodes of peritonitis (P = 0.047). Multivariable analysis showed that lower education, Kt/V, and nPCR were the most relevant factors connected to MCI (P = 0.029, P = 0.037, and P = 0.019, respectively).

Conclusion

In our PD population, MCI was detected in more than half of the patients. Patients with MCI were older, had lower education level, more disease burden, and higher risk for developing peritonitis. Lower Kt/V and nPCR levels were associated with MCI.

Cognitive Impairment and Brain Atrophy in Patients with Chronic Kidney Disease

In Japan, the aging of the population is rapidly accelerating, with an increase in patients with chronic kidney disease (CKD) and those undergoing dialysis. As a result, the number of individuals with cognitive impairment (CI) is rising, and addressing this issue has become an urgent problem. A notable feature of dementia in CKD patients is the high frequency of vascular dementia, making its prevention through the management of classical risk factors such as hypertension, diabetes mellitus, dyslipidemia, smoking, etc., associated with atherosclerosis and arteriosclerosis. Other effective measures, including the use of renin-angiotensin system inhibitors, addressing anemia, exercise therapy, and lifestyle improvements, have been reported. The incidence and progression of CI may also be influenced by the type of kidney replacement therapy, with reports suggesting that long-duration dialysis, low-temperature hemodialysis, peritoneal dialysis, and kidney transplantation can have a preferable effect on the preservation of cognitive function. In conclusion, patients with CKD are at a higher risk of developing CI, with brain atrophy being a contributing factor. Despite the identification of various preventive measures, the evidence substantiating their efficacy remains limited across all studies. Future expectations lie in large-scale randomized controlled trials.

[Neuropsychological impairments in patients undergoing peritoneal dialysis treatment]

BACKGROUND

Patients with chronic kidney disease on hemodialysis (HD) often have cognitive deficits. However, there are few studies that have examined the neuropsychological impairments of patients receiving peritoneal dialysis (PD).

METHODS

Executive functions, processing speed and verbal memory were assessed in 27 PD patients, 42 HD patients, and 42 healthy participants (HP). Systolic blood pressure and total time on renal replacement therapy (RRT) were controlled statistically. Associations between performance and clinical factors were analyzed using correlations and multiple regression.

RESULTS

The DP group showed better performance compared to the HD group in verbal fluency, working memory, cognitive flexibility, planning and decision making. The DP group showed worse execution than the HP group in verbal inhibition and memory. Executive function scores were positively associated with total months on PD, total months on RRT, total months on HD, albumin, total cholesterol, and phosphorus, and negatively with ferritin.

CONCLUSION

Global executive functioning was more optimal in PD patients than in HD patients. The results show the positive effect of PD on executive functions, which must be taken into account when choosing the TRS. The associations observed between biochemical factors and performance show the importance of maintaining an adequate nutritional status in these patients.

Subjective cognitive complaints in end-stage renal disease: a systematic review and meta-analysis

Cognitive impairment is common in patients with end-stage renal disease (ESRD) and is associated with compromised quality of life and functional capacity, as well as worse clinical outcomes. Most previous research and reviews in this area were focused on objective cognitive impairment, whereas patients' subjective cognitive complaints (SCCs) have been less well-understood. This systematic review aimed to provide a broad overview of what is known about SCCs in adult ESRD patients. Electronic databases were searched from inception to January 2022, which identified 221 relevant studies. SCCs appear to be highly prevalent in dialysis patients and less so in those who received kidney transplantation. A random-effects meta-analysis also shows that haemodialysis patients reported significantly more SCCs than peritoneal dialysis patients (standardised mean difference -0.20, 95% confidence interval -0.38 to -0.03). Synthesis of longitudinal studies suggests that SCCs remain stable on maintenance dialysis treatment but may reduce upon receipt of kidney transplant. Furthermore, SCCs in ESRD patients have been consistently associated with hospitalisation, depression, anxiety, fatigue, and poorer quality of life. There is limited data supporting a strong relation between objective and subjective cognition but preliminary evidence suggests that this association may be domain-specific. Methodological limitations and future research directions are discussed.

Outcomes of Remote Patient Monitoring in Peritoneal Dialysis: A Meta-Analysis and Review of Practical Implications for COVID-19 Epidemics

The present study seeks to determine clinical outcomes associated with remote patient monitoring of peritoneal dialysis (RPM-PD), with potential implications during COVID-19 outbreaks. We performed a systematic review in the PubMed, Embase, and Cochrane databases. We combined all study-specific estimates using the inverse-variant weighted averages of logarithmic relative risk (RR) in the random-effects models. Confidence interval (CI) including the value of 1 was used as evidence to produce a statistically significant estimate. Twenty-two studies were included in our meta-analysis. Quantitative analysis demonstrated that RPM-PD patients had lower rates of technique failure (log RR = -0.32; 95% CI, -0.59 to -0.04), lower hospitalization rates (standardized mean difference = -0.84; 95% CI, -1.24 to -0.45), and lower mortality rates (log RR = -0.26; 95% CI, -0.44 to -0.08) compared with traditional PD monitoring. RPM-PD has better outcomes in multiple spheres of outcomes when compared with conventional monitoring and likely increases system resilience during disruptions of healthcare operations.

The impact of hemodiafiltration on cognitive function in patients with end-stage renal disease

Background

Patients with end-stage renal disease are more likely to suffer cognitive impairment. Cognitive impairment may lead to long-term severe adverse consequences.

Purpose

To explore the impact of different blood purification therapy on cerebral blood flow and cognitive functions in end-stage renal disease.

Materials and methods

This prospective study evaluated patients with end-stage renal disease undergoing blood purification from January to March 2021. Matched healthy controls were also included. Participants performed neurocognitive measurements, including a mini-mental state examination, logical memory test-20-minutes delayed, verbal fluency test, digit span test, clock drawing test, and stroop color and word test C. In addition, we tested plasma amyloid-β protein levels, serum Fe and hemoglobin levels in blood samples. Cerebral blood flow was measured using pulsed pseudocontinuous arterial spin labeling. We analyzed and compared the correlation between cognitive function, biomarkers, and cerebral blood flow between patients and healthy subjects, as well as between patients with different treatments.

Results

A total of 44 patients with end-stage renal disease (mean age, 57.39 years ± 8.63) and 46 healthy controls (mean age, 56.15 years ± 6.40) were recruited. Patients receive hemodialysis three times a week, and 27 of them have been replaced hemodialysis for hemodiafiltration twice a month. The cognitive function of patients was worse than healthy controls (P < 0.05). The patients showed higher plasma concentrations of amyloid-β40, amyloid-β42, Tau, and pTau181 than healthy controls (P < 0.05). The group receiving both hemodialysis and hemodiafiltration had higher cerebral blood flow signal values in the left caudate nucleus (chuster-level P < 0.05, voxel-level P < 0.001). They also exhibited better verbal fluency function than the hemodialysis-only group (P < 0.05).

Conclusion

Patients with the end-stage renal disease showed widespread cognitive declines. Cerebral blood flow generally decreased in the cerebral cortex and increased in subcortical regions. The hemodiafiltration may protect verbal function by increasing cerebral blood flow in the left caudate.

Comparative Analysis of Efficacy and Prognosis of Hemodialysis and Peritoneal Dialysis for End-Stage Renal Disease: A Meta-analysis

Objective

This meta-analysis is aimed at systematically assessing the efficacy and prognosis of hemodialysis (HD) and peritoneal dialysis (PD) in the treatment of end-stage renal disease (ESRD).

Methods

China National Knowledge Infrastructure, VIP, SinoMed, Cochrane Library, PubMed, and Embase databases were searched for relevant studies to evaluate the two different dialysis methods for ESRD. The search time was set from 2010 to 2021. Meta-analysis was performed using Stata16.0. The treatment group received PD, while the control group was given HD.

Results

Out of 317 articles initially retrieved, 14 studies were finally included in our meta-analysis. The analysis results showed that there was no marked difference in the 1-year survival rate between the two groups (RR = 1.05; 95% CI: 1.00, 1.10; P > 0.05), but the incidence rate of adverse reactions in the treatment group was significantly lower than that in the control group (RR = 0.51; 95% CI: 0.37, 0.70; P < 0.05). In addition, PD and HD treatments caused significant decreases in serum creatinine levels (PD, SMD = −2.91; 95% CI: -3.79, -2.04; P < 0.05; HD, SMD = −3.09; 95% CI: -4.01, -2.16; P < 0.05) and blood urea nitrogen levels (PD, SMD = −2.54, 95% CI: -3.37, -1.72, P < 0.05; HD, SMD = −2.62, 95% CI: -3.47, -1.77, P < 0.05); however, there was no significant statistical difference in posttreatment levels of serum creatinine and blood urea nitrogen between the two groups. Compared with the control group, the hemoglobin (SMD = 0.56, 95% CI: 0.07, 1.06; P < 0.05) and serum albumin (SMD = 1.11, 95% CI: 0.46, 1.76, P < 0.05) levels were significantly increased in the treatment group after treatment.

Conclusion

In summary, both PD and HD can improve renal function in uremic patients, but PD is superior to HD in reducing the incidence of adverse reactions, improving the nutritional status, and therefore improving the quality of life of patients.

Peritoneal Dialysis for Potential Kidney Transplant Recipients: Pride or Prejudice?

Kidney transplantation (KT) is recognized as the gold-standard of treatment for patients with end-stage renal disease. Additionally, it has been demonstrated that receiving a pre-emptive KT ensures the best recipient and graft survivals. However, due to an overwhelming discrepancy between the organs available and the patients on the transplant waiting list, the vast majority of transplant candidates require prolonged periods of dialysis before being transplanted. For many years, peritoneal dialysis (PD) and hemodialysis (HD) have been considered competitive renal replacement therapies (RRT). This dualistic vision has recently been questioned by evidence suggesting that an individualized and flexible approach may be more appropriate. In fact, tailored and cleverly planned changes between different RRT modalities, according to the patient's needs and characteristics, are often needed in order to achieve the best results. While home HD is still under scrutiny in this particular setting, current data seems to favor the use of PD over in-center HD in patients awaiting a KT. In this specific population, the demonstrated advantages of PD are superior quality of life, longer preservation of residual renal function, lower incidence of delayed graft function, better recipient survival, and reduced cost.

Retrospective analysis of nontraumatic subdural hematoma incidence and outcomes in Egyptian patients with end-stage renal disease on hemodialysis

Background

The incidence of subdural hematoma (SDH) in chronic maintenance hemodialysis (CMH) patients may change over time, along with the evolving characteristics of the underlying populations.

Methods

We conducted a retrospective, single-center study at Cairo University hospitals, assessing the incidence, associated risk factors, and outcomes of nontraumatic SDH in CMH patients between January 2006 and January 2019.

Results

Out of 1217 CMH patients, nontraumatic SDH was diagnosed in 41 (3.37%) during the study, increasing with the enrollees’ age but stable over the observation period and translating into an annual incidence rate of 28 per 1000 patients per year. SDH patients were likely to use central venous catheters, reported pruritis and history of bone fractures, and had higher phosphorus, parathyroid hormone, and alkaline phosphatase values (p < 0.001); however, there was no association with atrial fibrillation or use of anticoagulants. In the SDH cohort (n = 41), six patients did not need surgical intervention and 13 patients died before becoming surgically fit for intervention; mortality correlated with ischemic heart disease (p = 0.033) and the presence of atrial fibrillation or chronic anticoagulation with warfarin (p < 0.0001 for both), among others. Twenty-two patients received surgical operations and of these 2 died postoperatively; overall patient mortality was 12/41 (29.27%) at 30 days and 15/41 (36.59%) at 1 year.

Conclusion

Our study demonstrated a striking enrichment for underlying comorbidities in those patients developing SDH and a high risk of immediate mortality. The benefit of chronic anticoagulation therapy should be carefully weighed against the risk of CNS bleed in MHD patients.

Evaluation of cerebral dysfunction in patients with chronic kidney disease using neuropsychometric and neurophysiological tests

Background

Uremic encephalopathy is defined as cerebral dysfunction due to toxin accumulation in patients with chronic kidney disease (CKD). This condition is characterized by subtle to florid symptoms, and its clinical course is always progressive when untreated but partially reversible with renal replacement therapy. While no test exists to measure subclinical uremic encephalopathy, two tests have been validated to measure minimal hepatic encephalopathy: the critical flicker frequency (CFF) test and the psychometric hepatic encephalopathy score (PHES).

Objective

To use CFF and PHES to measure the prevalence of cerebral dysfunction in individuals with CKD.

Methods

This cross-sectional study included a total of 69 patients with stage-5 CKD. Cutoff points for minimal encephalopathy were established using existing clinical guidelines: ≤39 Hz for CFF and < −4 for PHES. All participants were also screened for cognitive function and depression.

Results

Eighteen cases (26.1%) of cerebral dysfunction linked to uremic encephalopathy were detected with CFF, while twelve (17.4%) were detected by PHES; only six cases (8.7%) were diagnosed by both methods. Half of the cases (50%) had diabetes, and 61% were on hemodialysis. Cognitive function scores did not differ significantly between those receiving dialysis, hemodialysis, or no renal replacement therapy.

Conclusions

It is essential to identify cerebral dysfunction when uremic encephalopathy is in early subclinical stages to reduce preventable events as traffic and work accidents.

Sufficiency of Knowledge Processed in Patient Education in Dialysis Care

PURPOSE

Patient education improves health and treatment adherence of patients with chronic kidney disease. However, evidence about the sufficiency of patients' knowledge processed in patient education is limited. The purpose of this study was to evaluate subjective and objective sufficiency of knowledge processed in patient education in dialysis care and treatment.

PATIENTS AND METHODS

A cross-sectional study design was used. The sample (n=162) comprised patients in predialysis or home dialysis. All eligible patients during the data collection timeframe (2016-2017) in two university hospital districts in Finland were invited to participate. Subjective sufficiency was evaluated with a structured questionnaire having 34 items divided into six dimensions of empowering knowledge (bio-physiological, functional, social, experiential, ethical, and financial) on a Likert scale (1=not sufficient at all, 4=very sufficient). Objective sufficiency was evaluated with a structured knowledge test with 10 items (score range 0-10, correct=1, wrong/no knowledge=0) based on the multidimensional content of patient education emphasizing bio-physiological dimension.

RESULTS

In subjective sufficiency of knowledge, the mean was 3.27 (SD 0.54). The bio-physiological dimension of empowering knowledge was the most sufficient (mean 3.52, SD 0.49) and the experiential the least (mean 2.8, SD 0.88). In objective sufficiency, the means ranged 5.15-5.97 (SD 2.37-2.68) among patients in different modalities of dialysis care and treatment. The least sufficient objective scores were bio-physiological and functional knowledge. The subjective and objective sufficiency did not correlate with each other.

CONCLUSION

Patients' knowledge, either subjective or objective, does not seem to be sufficient. Hence, attention should be paid to supporting patients with more personalized knowledge. Furthermore, the relationship between subjective and objective sufficiency needs future consideration, as their non-correspondence was a new discovery.