Sex-Based Differences in Risk Factors and Complications of Chronic Kidney Disease

Sex Differences in Cardiovascular-Kidney-Metabolic Syndrome: 30-Year US Trends and Mortality Risks-Brief Report

BACKGROUND

The American Heart Association recently published guidelines on how to clinically identify and categorize individuals with cardiovascular-kidney-metabolic (CKM) syndrome. The extent to which CKM syndrome prevalence and prognosis differ by sex remains unknown. This study aimed to examine the impact of sex on trends in prevalence over 30 years and the long-term prognosis of CKM syndrome in the United States.

METHODS

We analyzed nationally representative National Health and Nutrition Examination Survey 1988 to 2018 data collected from 33 868 US adults (aged ≥20 years) who were under surveillance for all-cause mortality through December 31, 2019. We examined the sex-specific prevalence of CKM syndrome and sex-specific CKM associations with all-cause mortality.

RESULTS

Of the 33 868 adults studied, the mean±SD age was 48.4±18.3 years with 52% women and 56% non-White. Overall prevalence of CKM syndrome increased steadily from 1988 to 2018 in both sexes, with a larger temporal rise in prevalent stage 3 CKM seen for men (from 18.9% to 22.4%) compared with women (from 13.9% to 15.2%). Over a median follow-up of 13.3 years, there were 8745 deaths. In the multivariable Cox regression analysis, worsening CKM severity was associated with all-cause mortality (P<0.001 for both sexes), with greater magnitudes of risk seen in women (hazards ratio, 1.24-3.33) compared with men (hazards ratio, 0.85-2.60) across all stages (likelihood ratio test χ2, 19.0; Pinteraction<0.001); results were similar for cardiovascular mortality (likelihood ratio test χ2, 22.3; Pinteraction<0.001).

CONCLUSIONS

Women, compared with men, exhibited a lower prevalence of CKM stage 3 but experienced excess mortality risk across the spectrum of multisystem CKM dysfunction. These findings underscore the importance of identifying mechanisms underlying joint cardiovascular, kidney, and metabolic system pathophysiology to close a potentially widening sex disparities gap in multiorgan disease risk.

Sex differences in chronic kidney disease-related complications and mortality across levels of glomerular filtration rate

BACKGROUND

Chronic kidney disease (CKD) is a growing global health concern. Recent research has indicated sex disparities in CKD-related complications, yet the impact of sex differences on critical kidney function levels that trigger these complications and mortality remains inadequately documented.

METHODS

We investigated sex-specific disparities in CKD-related complications and mortality according to estimated glomerular filtration rate (eGFR) levels. We analyzed National Health and Nutrition Examination Survey (NHANES) data spanning from 1999 to 2018, including adult participants with an eGFR of 15-150 mL/min/1.73 m2. The outcomes were CKD-related complications [hypertension, anaemia, cardiovascular (CV) diseases, acidosis, hyperphosphatemia, hyperparathyroidism] and all-cause and cause-specific mortality (CV mortality and non-CV mortality). Sex-stratified multivariable logistic and Cox regression models yielded odds ratios and hazard ratios for the relationship between eGFR categories and outcomes. Sex-stratified natural splines were used to explore the relationship between continuous eGFR and outcomes and identified eGFR thresholds of statistical significance.

RESULTS

The study included 49 558 participants (50.3% women, 49.7% men). Multivariable logistic regression demonstrated a significant eGFR association with all CKD-related complications, exhibiting a linear trend across eGFR categories. Modelling eGFR as a natural spline revealed varied significance thresholds between sexes for anaemia and hyperparathyroidism. Additionally, the eGFR-hyperphosphatemia association was more pronounced in men. We observed substantial but not statistically significant differences between men and women in the thresholds of statistical significance for CV (significance appeared at a higher eGFR in men) and non-CV mortality (significance appeared at a higher eGFR in women).

CONCLUSIONS

Research shows sex disparities in most CKD-related complications. Men develop anaemia and hyperparathyroidism earlier; women show a steeper anaemia increase. Men have higher CV mortality risk. As eGFR decreased, men faced a higher risk of CV mortality at a higher eGFR threshold than women.

Sex-Specific Impact of Serum Calcium Levels on Acute Coronary Syndrome Risk: A 19-Year Cohort Study in Korea

Background: This study aims to investigate the association between serum calcium levels and acute coronary syndrome (ACS) risk, examining whether this relationship differs by sex, given the known differences in calcium metabolism and hormonal influences between males and females. Methods: Utilizing the Korean Genome Epidemiology Study (KoGES) prospective cohort data, our primary exposure variables were serum calcium level and sex. The incidence of ACS served as the main outcome of interest. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox regression analysis. An interaction analysis was conducted to assess the interaction effect of calcium level and sex on ACS incidence. Results: After adjusting for confounding variables, high calcium intake did not significantly increase ACS incidence, with a hazard ratio (HR) of 1.07 (95% CI: 0.90-1.26). There was also no significant difference in ACS risk between females and males (HR: 0.81, 95% CI: 0.61-1.04). However, interaction effect analysis revealed that higher calcium levels were associated with an increased risk of ACS only in females (HR: 1.24, 95% CI: 1.07-1.58), whereas the association in males was not statistically significant (HR: 0.90, 95% CI: 0.71-1.15). Conclusion: Our study results indicate that elevated serum calcium levels alone did not independently increase the risk of ACS; however, high serum calcium levels were associated with an increased risk of ACS in females but not in males, underscoring the importance of sex-specific factors in assessing and managing ACS risk and highlighting the necessity for personalized medical approaches to improve cardiovascular health outcomes for women.

Sex-disaggregated analysis of acute kidney injury in hospitalized children with sickle cell anemia in Uganda

A growing body of research is categorizing sex differences in both sickle cell anemia (SCA) and acute kidney injury (AKI); however, most of this work is being conducted in high-resource settings. Here, we evaluated risk factors and clinical parameters associated with AKI and AKI severity, stratified by sex, in a cohort of children hospitalized with SCA and vaso-occlusive pain crisis (VOC). The purpose of this study was to explore sex disparities in a high-risk, vulnerable population. This study was a secondary analysis of data collected from a cohort of Ugandan children between 2 and 18 yr of age prospectively enrolled. A total of 185 children were enrolled in the primary study; 41.6% were female and 58.4% were male, with a median age of 8.9 yr. Incident or worsening AKI (P = 0.026) occurred more frequently in female compared with male children, despite no differences in AKI on admission. Female children also had altered markers of renal function including higher creatinine levels at admission (P = 0.03), higher peak creatinine (P = 0.006), and higher urine neutrophil gelatinase-associated lipocalin (NGAL) at admission (P = 0.003) compared with male children. Female children had elevated total (P = 0.045) and conjugated bilirubin at admission (P = 0.02) compared with male children and higher rates of hematuria at admission (P = 0.004). Here, we report sex differences in AKI in children with SCA and VOC, including increased incidence and worsening of AKI in female pediatric patients, in association with an increase in biological indicators of poor renal function including creatinine, estimated glomerular filtration rate, and NGAL.NEW & NOTEWORTHY In this study, we report an increased risk of developing acute kidney injury (AKI) during hospitalization, worsening AKI, and death among females with sickle cell anemia (SCA) hospitalized with an acute pain crisis compared with males. The sex differences in AKI were not explained by socioeconomic differences, severity of pain, or disease severity among females compared with males. Together, these data suggest that female children with SCA may be at increased risk of AKI.

Chronic kidney disease and the global public health agenda: an international consensus

Early detection is a key strategy to prevent kidney disease, its progression and related complications, but numerous studies show that awareness of kidney disease at the population level is low. Therefore, increasing knowledge and implementing sustainable solutions for early detection of kidney disease are public health priorities. Economic and epidemiological data underscore why kidney disease should be placed on the global public health agenda - kidney disease prevalence is increasing globally and it is now the seventh leading risk factor for mortality worldwide. Moreover, demographic trends, the obesity epidemic and the sequelae of climate change are all likely to increase kidney disease prevalence further, with serious implications for survival, quality of life and health care spending worldwide. Importantly, the burden of kidney disease is highest among historically disadvantaged populations that often have limited access to optimal kidney disease therapies, which greatly contributes to current socioeconomic disparities in health outcomes. This joint statement from the International Society of Nephrology, European Renal Association and American Society of Nephrology, supported by three other regional nephrology societies, advocates for the inclusion of kidney disease in the current WHO statement on major non-communicable disease drivers of premature mortality.

Novel Perspectives in Chronic Kidney Disease-Specific Cardiovascular Disease

Chronic kidney disease (CKD) affects > 10% of the global adult population and significantly increases the risk of cardiovascular disease (CVD), which remains the leading cause of death in this population. The development and progression of CVD-compared to the general population-is premature and accelerated, manifesting as coronary artery disease, heart failure, arrhythmias, and sudden cardiac death. CKD and CV disease combine to cause multimorbid cardiorenal syndrome (CRS) due to contributions from shared risk factors, including systolic hypertension, diabetes mellitus, obesity, and dyslipidemia. Additional neurohormonal activation, innate immunity, and inflammation contribute to progressive cardiac and renal deterioration, reflecting the strong bidirectional interaction between these organ systems. A shared molecular pathophysiology-including inflammation, oxidative stress, senescence, and hemodynamic fluctuations characterise all types of CRS. This review highlights the evolving paradigm and recent advances in our understanding of the molecular biology of CRS, outlining the potential for disease-specific therapies and biomarker disease detection.

Are Differences in Living Kidney Donation Rates a Sex or a Gender Disparity?

Sex-disaggregated data reveal significant disparities in living kidney donation, with more female than male living kidney donors in most countries and proportions over 60% in some countries. We summarize the present state of knowledge with respect to the potential drivers of this disparity and argue that it is primarily driven by gender-related factors. First, we present the differences between sex and gender and then proceed to summarize the potential medical reasons that have been proposed to explain why males are less likely to be living kidney donors than females, such as the higher prevalence of kidney failure in males. We then present counterarguments as to why biological sex differences are not enough to explain lower living kidney donation among males, such as a higher prevalence of chronic kidney disease among females, which could affect donation rates. We argue that gender differences likely provide a better explanation as to why there are more women than men living kidney donors and explore the role of economic and social factors, as well as gender roles and expectations, in affecting living kidney donation among both men and women. We conclude with the need for a gender analysis to explain this complex psychosocial phenomenon in living kidney donation.

Association between cumulative uric acid to high-density lipoprotein cholesterol ratio and the incidence and progression of chronic kidney disease

Objective

The ratio of uric acid to high-density lipoprotein cholesterol (UHR) was related to the risk of chronic kidney disease (CKD), we aimed to investigate the association of cumulative UHR (cumUHR) with incidence and progression of CKD.

Methods

Our study included a total of 49,913 participants (mean age 52.57 years, 77% males) from the Kailuan Study conducted between 2006 and 2018. Participants who completed three consecutive physical examinations were included. Cumulative UHR (cumUHR) was computed as the summed average UHR between two consecutive physical examinations, multiplied by the time between the two examinations. Participants were then categorized into four groups based on cumUHR quartiles. Subsequently, participants were further divided into a CKD group and a non-CKD group. The associations between cumUHR and CKD and it's progression were assessed by Cox proportional hazards regression models. The cumulative incidence of endpoint events was compared between the cumUHR groups using the log-rank test. The C-index, net reclassification improvement (NRI) and integrated discrimination improvement (IDI) were calculated to assess the predictive performance of cumUHR.

Results

After a mean follow-up of 8.0 ± 1.7 years, there were 4843 cases of new-onset CKD, 2504 of low eGFR, and 2617 of proteinuria in the non-CKD group. Within the CKD group, there were 1952 cases of decline in eGFR category, 1465 of >30% decline in eGFR, and 2100 of increased proteinuria. In the non-CKD group, the adjusted hazard ratios (HRs) and confidence intervals (CIs) in the fourth quartile were 1.484 (1.362-1.617), 1.643 (1.457-1.852), and 1.324 (1.179-1.486) for new-onset CKD, low eGFR, and proteinuria, respectively. In the CKD group, the adjusted HRs in the fourth quartile were 1.337 (1.164-1.534), 1.428 (1.216-1.677), and 1.446 (1.267-1.651) for decline in eGFR category, >30% decline in eGFR, and increase in proteinuria, respectively. In addition, we separately added a single UHR measurement and cumUHR to the CKD base prediction model and the CKD progression base prediction model, and found that the models added cumUHR had the highest predictive value.

Conclusion

High cumUHR exposure was an independent risk factor for the incidence and progression of CKD, and it was a better predictor than a single UHR measurement.

Smokeless tobacco consumption and its association with risk factors of chronic kidney disease in rural and peri-urban Bangladesh

INTRODUCTION

Compared to smoking, which has major consequences in chronic kidney disease (CKD) initiation and progression, smokeless tobacco (SLT) consumption is considered to have fewer health consequences. We investigated the prevalence of SLT consumption and its association with risk factors of CKD in a rural and peri-urban Bangladeshi population.

METHODS

Using random sampling we recruited 872 adults in 2020, from the Mirzapur Demographic Surveillance System of Bangladesh, who had resided in the area for at least five years. Interviews using a semi-structured questionnaire, physical examination and anthropometric measurements were done, followed by blood and urine testing. The blood and urine tests were repeated in selected participants after three months as per the CKD Epidemiology Collaboration equation.

RESULTS

The prevalence of SLT consumption was 29%. Being aged ≥46 years (OR=7.10; 95% CI: 4.79-10.94), female (OR=1.64; 95% CI: 1.21-2.22), housewife (OR=1.82; 95% CI: 1.35-2.45), farmer (OR=1.71; 95% CI: 1.06-2.76), widow (OR=3.40; 95% CI: 2.24-5.17), and having no formal schooling (OR=4.91; 95% CI: 3.59-6.72), family income of <$100/month (OR=1.66; 95% CI: 1.13-2.43), sleeping duration <7 hours per day (OR=2.33; 95% CI: 1.70-3.19), were associated with a significantly higher odds of SLT consumption. However, being aged 31-45 years (OR=0.25; 95% CI: 0.16-0.38) had significantly lower odds of being an SLT consumer. Among the diseases investigated, undernutrition (OR=1.63; 95% CI: 1.15-2.33), hypertension (OR=1.52; 95% CI: 1.13-2.05), anemia (OR=1.94; 95% CI: 1.39-2.71) and CKD (OR=1.62; 95% CI: 1.15-2.27) were significantly associated with SLT consumption. In the multivariable analysis, being aged 31-45 years (AOR=3.06; 95% CI: 1.91-4.90), ≥46 years (AOR=15.69; 95% CI: 4.64-53.09) and having no formal schooling (AOR=2.47; 95% CI: 1.72-3.55) were found to have a significant association with being an SLT consumer.

CONCLUSIONS

SLT consumption is associated with most of the established risk factors of CKD within the studied population.

Association between the High-Sensitivity C-Reactive Protein/Albumin Ratio and New-Onset Chronic Kidney Disease in Chinese Individuals

INTRODUCTION

Inflammation is associated with development of chronic kidney disease (CKD). However, the association of the high-sensitivity C-reactive protein (hs-CRP)/albumin ratio (CAR) on the risk of CKD in the general population is unknown. This study explored the relationship between the CAR and CKD and the ability of this ratio to predict CKD in the general population.

METHODS

A total of 47,472 participants in the Kailuan study who met the inclusion criteria in 2010 were selected and grouped using the quartile method. A Cox proportional hazard regression model was used to evaluate the association of the CAR on the risk of CKD. The C-index, net reclassification index (NRI), and overall identification index (IDI) were calculated to evaluate the ability of the CAR to predict CKD.

RESULTS

During a follow-up of 378,383 person-years, CKD events occurred in 6,249 study participants (13.16%). The Cox proportional hazard regression model showed that the hazard ratio (95% confidence interval) for CKD events was 1.18 (1.10-1.28) in the Q3 group and 1.42 (1.32-1.53) in the Q4 group when compared with the Q1 group. Compared with the single index, the C-index, NRI, and IDI values were significantly improved when the CAR was added for prediction of risk of CKD.

CONCLUSIONS

A higher CAR was an independent risk factor for CKD. The ability of the CAR to predict CKD was better than that of hs-CRP or albumin. The CAR provides an important reference index for predicting the risk of CKD.

Gender-based research underscores sex differences in biological processes, clinical disorders and pharmacological interventions

Earlier research has presumed that the male and female biology is similar in most organs except the reproductive system, leading to major misconceptions in research interpretations and clinical implications, with serious disorders being overlooked or misdiagnosed. Careful research has now identified sex differences in the cardiovascular, renal, endocrine, gastrointestinal, immune, nervous, and musculoskeletal systems. Also, several cardiovascular, immunological, and neurological disorders have shown differences in prevalence and severity between males and females. Genetic variations in the sex chromosomes have been implicated in several disorders at young age and before puberty. The levels of the gonadal hormones estrogen, progesterone and testosterone and their receptors play a role in the sex differences between adult males and premenopausal women. Hormonal deficiencies and cell senescence have been implicated in differences between postmenopausal and premenopausal women. Specifically, cardiovascular disorders are more common in adult men vs premenopausal women, but the trend is reversed with age with the incidence being greater in postmenopausal women than age-matched men. Gender-specific disorders in females such as polycystic ovary syndrome, hypertension-in-pregnancy and gestational diabetes have attained further research recognition. Other gender-related research areas include menopausal hormone therapy, the "Estrogen Paradox" in pulmonary arterial hypertension being more predominant but less severe in young females, and how testosterone may cause deleterious effects in the kidney while having vasodilator effects in the coronary circulation. This has prompted the National Institutes of Health (NIH) initiative to consider sex as a biological variable in research. The NIH and other funding agencies have provided resources to establish state-of-the-art centers for women health and sex differences in biology and disease in several academic institutions. Scientific societies and journals have taken similar steps to organize specialized conferences and publish special issues on gender-based research. These combined efforts should promote research to enhance our understanding of the sex differences in biological systems beyond just the reproductive system, and provide better guidance and pharmacological tools for the management of various clinical disorders in a gender-specific manner.

Cardiovascular Outcomes in De Novo Kidney Transplant Recipients Receiving Everolimus and Reduced Calcineurin Inhibitor or Standard Triple Therapy: 24-month Post Hoc Analysis From TRANSFORM Study

BACKGROUND

The comparative impact of everolimus (EVR)-based regimens versus standard of care (mycophenolic acid+standard calcineurin inhibitor [MPA+sCNI]) on cardiovascular outcomes in de novo kidney transplant recipients (KTRs) is poorly understood. The incidence of major adverse cardiac events (MACEs) in KTRs receiving EVR+reduced CNI (rCNI) or MPA+sCNI from the TRANSplant eFficacy and safety Outcomes with an eveRolimus-based regiMen study was evaluated.

METHODS

The incidence of MACE was determined for all randomized patients receiving at least 1 dose of the study drug. Factors associated with MACEs were determined by logistic regression. Risk of MACE out to 3 y post-study was calculated using the Patient Outcome in Renal Transplantation equation.

RESULTS

MACE occurred in 81 of 1014 (8.0%; EVR+rCNI) versus 89 of 1012 (8.8%; MPA+sCNI) KTRs (risk ratio, 0.91 [95% confidence interval [CI], 0.68-1.21]). The incidence of circulatory death, myocardial infarction, revascularization, or angina was similar between the arms. Incidence of MACE was similar between EVR+rCNI and MPA+sCNI arms with a higher incidence in prespecified risk groups: older age, pretransplant diabetes (15.1% versus 15.9%), statin use (8.5% versus 10.8%), and low estimated glomerular filtration rate (Month 2 estimated glomerular filtration rate <30 versus >60 mL/min/1.73 m 2 ; odds ratio, 2.23 [95% CI, 1.02-4.86]; P = 0.044), respectively. Predicted risk of MACE within 3 y of follow-up did not differ between the treatment arms.

CONCLUSIONS

Cardiovascular morbidity and mortality were similar between de novo KTRs receiving EVR+rCNI and MPA+sCNI. EVR+rCNI is a viable alternative to the current standard of care in KTRs.

Risk factors for heart, cerebrovascular, and kidney diseases: evaluation of potential side effects of medications to control hypertension, hyperglycemia, and hypercholesterolemia

Background

Heart disease (HD), cerebrovascular disease (CBD), and kidney disease (KD) are serious diseases worldwide. These diseases constitute the leading causes of death worldwide and are costly to treat. An analysis of risk factors is necessary to prevent these diseases.

Data and Methods

Risk factors were analyzed using data from 2,837,334, 2,864,874, and 2,870,262 medical checkups obtained from the JMDC Claims Database. The side effects of medications used to control hypertension (antihypertensive medications), hyperglycemia (antihyperglycemic medications), and hypercholesterolemia (cholesterol medications), including their interactions, were also evaluated. Logit models were used to calculate the odds ratios and confidence intervals. The sample period was from January 2005 to September 2019.

Results

Age and history of diseases were found to be very important factors, and the risk of having diseases could be almost doubled. Urine protein levels and recent large weight changes were also important factors for all three diseases and made the risks 10%-30% higher, except for KD. For KD, the risk was more than double for individuals with high urine protein levels. Negative side effects were observed with antihypertensive, antihyperglycemic, and cholesterol medications. In particular, when antihypertensive medications were used, the risks were almost doubled for HD and CBD. The risk would be triple for KD when individuals were taking antihypertensive medications. If they did not take antihypertensive medications and took other medications, these values were lower (20%-40% for HD, 50%-70% for CBD, and 60%-90% for KD). The interactions between the different types of medications were not very large. When antihypertensive and cholesterol medications were used simultaneously, the risk increased significantly in cases of HD and KD.

Conclusion

It is very important for individuals with risk factors to improve their physical condition for the prevention of these diseases. Taking antihypertensive, antihyperglycemic, and cholesterol medications, especially antihypertensive medications, may be serious risk factors. Special care and additional studies are necessary to prescribe these medications, particularly antihypertensive medications.

Limitations

No experimental interventions were performed. As the dataset was comprised of the results of health checkups of workers in Japan, individuals aged 76 and above were not included. Since the dataset only contained information obtained in Japan and the Japanese are ethnically homogeneous, potential ethnic effects on the diseases were not evaluated.

Sex Differences in Inflammation and Muscle Wasting in Aging and Disease

Only in recent years, thanks to a precision medicine-based approach, have treatments tailored to the sex of each patient emerged in clinical trials. In this regard, both striated muscle tissues present significant differences between the two sexes, which may have important consequences for diagnosis and therapy in aging and chronic illness. In fact, preservation of muscle mass in disease conditions correlates with survival; however, sex should be considered when protocols for the maintenance of muscle mass are designed. One obvious difference is that men have more muscle than women. Moreover, the two sexes differ in inflammation parameters, particularly in response to infection and disease. Therefore, unsurprisingly, men and women respond differently to therapies. In this review, we present an up-to-date overview on what is known about sex differences in skeletal muscle physiology and disfunction, such as disuse atrophy, age-related sarcopenia, and cachexia. In addition, we summarize sex differences in inflammation which may underly the aforementioned conditions because pro-inflammatory cytokines deeply affect muscle homeostasis. The comparison of these three conditions and their sex-related bases is interesting because different forms of muscle atrophy share common mechanisms; for instance, those responsible for protein dismantling are similar although differing in terms of kinetics, severity, and regulatory mechanisms. In pre-clinical research, exploring sexual dimorphism in disease conditions could highlight new efficacious treatments or recommend implementation of an existing one. Any protective factors discovered in one sex could be exploited to achieve lower morbidity, reduce the severity of the disease, or avoid mortality in the opposite sex. Thus, the understanding of sex-dependent responses to different forms of muscle atrophy and inflammation is of pivotal importance to design innovative, tailored, and efficient interventions.