Serum Albumin and Cerebro-cardiovascular Mortality During a 15-year Study in a Community-based Cohort in Tanushimaru, a Cohort of the Seven Countries Study

The association between hypoalbuminemia and risk of death due to cancer and vascular disease in individuals aged 65 years and older: findings from the prospective Moli-sani cohort study

Background

Serum albumin is inversely associated with overall mortality, but its association with specific causes of death remains uncertain. This study aims to investigate whether hypoalbuminemia, defined as serum albumin levels ≤35 g/L, is associated with mortality specifically attributed to cancer and/or vascular diseases.

Methods

Serum albumin levels were measured in the population-based, prospective cohort of the Moli-sani study, established between 2005 and 2010. Hypoalbuminemia was defined as serum albumin levels ≤35 g/L. Cause-specific mortality was assessed using the validated Italian mortality registry and coded according to the International Classification of Diseases, Revision 9. Over a median follow-up period of 13.1 years, the relationship between serum albumin and mortality, adjusted for covariates, was investigated using competing-risk survival analysis.

Findings

The analysed cohort comprised 17,930 individuals aged ≥35 years, of whom 8445 were men (47.1%). The mean age was 54 years (standard deviation (SD) = 11 years), with 3299 individuals (18.4%) aged older than 65 years. All participants had C-reactive protein levels <10 mg/L and no history of liver, renal, cardiovascular, or cancer disease. Hypoalbuminemia was found in 406 individuals (2.3%). The study documented a total of 1428 deaths, with 574 attributed to cancer and 464 to vascular causes. Hypoalbuminemia was independently associated with mortality when compared to serum albumin >40 g/L (Hazard Ratio (HR) = 1.61, 95% Confidence Interval: 1.21-2.13). A decrease of 1-SD in serum albumin levels corresponded to HR of 1.16 (1.09-1.22), 1.16 (1.05-1.28), and 1.13 (1.03-1.23) for total, vascular and cancer mortality, respectively. Upon stratifying by age, hypoalbuminemia was associated with total mortality solely in those aged ≥65 years (HR = 1.83; 1.33-2.50) but not in the <65 years group (HR = 1.03; 0.53-2.00; P < 0.0001 for difference). Similar age-related patterns emerged for vascular death (per 1-SD decrease HR = 1.19; 1.07-1.33 in individuals ≥65 years and HR = 1.05; 0.86-1.29 in individuals <65 years) and cancer mortality (HR = 1.15; 1.02-1.30; ≥65 years and HR = 1.08; 0.96-1.23; <65 years).

Interpretation

Individuals ≥65 years old with serum albumin levels ≤35 g/L are at higher risk of total, cancer, and vascular mortality.

Funding

This paper was developed within the project funded by Next Generation EU-"Age-It - Ageing well in an ageing society" project (PE0000015), National Recovery and Resilience Plan (NRRP)-PE8-Mission 4, C2, Intervention 1.3.

Serum albumin and cardiovascular disease: a Mendelian randomization study

BACKGROUND

An increasing body of evidence suggests that serum albumin levels play a role in cardiovascular diseases. However, the specific causal relationship between serum albumin levels and cardiovascular disease remains partially unknown.

METHODS

Mendelian randomization (MR) was employed in this study to examine potential causal relationships between instrumental variables and cardiovascular diseases. Specifically, we utilized genetic variants of serum albumin levels within the reference range as our instrumental variables. To acquire data on genetic associations with cardiovascular diseases, we sourced information from renowned genome-wide association studies such as UK BioBank, EMBL-EBI, and FinnGen. Notably, our study leveraged summary statistics from large cohorts that have been previously described.

RESULTS

We explored the association between serum albumin levels and various conditions, including heart failure (HF), venous thromboembolism (VTE), stroke, atrial fibrillation (AF), coronary artery disease (CAD), type 2 diabetes (T2DM), and pulmonary heart disease (PHD). Genetically predicted serum albumin levels were associated with PHD (odds ratio = 0.737, 95% CI = 0.622 - 0.874, P < 0.001), AF (odds ratio = 0.922, 95% CI = 0.870 - 0.977, P = 0.006), VTE (odds ratio = 0.993, 95% CI = 0.991 - 0.995, P < 0.001), and Stroke (odds ratio = 0.997, 95% CI = 0.995 - 0.999, P = 0.002). However, genetically predicted serum albumin level traits were not associated with HF, CAD and T2DM.

CONCLUSION

Our study demonstrates a significant association between serum albumin levels and cardiovascular disease, underscoring the crucial role of low serum albumin as a predictive factor in patients with cardiovascular disease.

Association between extremely high-density lipoprotein cholesterol and adverse cardiovascular outcomes: a systematic review and meta-analysis

Background

The association between high-density lipoprotein cholesterol (HDL-C) and adverse cardiovascular outcomes is understudied. Based on cohort studies, the current study aimed to investigate the association of extremely high HDL-C with all-cause, atherosclerotic cardiovascular disease (CVD) mortality, and stroke risk.

Methods

A systematic literature search in Embase, PubMed, Cochrane Library, and Web of Science was performed to collect relevant cohort studies published before August 20, 2022. A random-effects model was used to pool relative risks (RRs) and 95% confidence intervals (CIs).

Results

A total of 17 cohort studies involving 19,630,829 participants were included, encompassing 18,547,132 total deaths (1,328,036 CVD deaths). All-cause mortality, CVD mortality, and stroke risk in the extremely high HDL-C group were increased by 15% (RR = 1.15, 95% CI:1.05-1.25), 14% (RR = 1.14, 95% CI:0.96-1.35) and 14% (RR = 1.14, 95% CI:0.82-1.58), compared to the normal HDL-C group. In subgroup analyses, extremely high HDL-C was associated with a reduced risk of CVD mortality in women and a lower risk of stroke in men compared to normal HDL-C levels.

Conclusions

The extremely high levels of HDL-C were associated with elevated risks of all-cause mortality, CVD mortality, and stroke. More well-designed studies are needed to confirm our findings.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=370201, identifier: CRD42022370201.

J-shaped association between serum albumin levels and long-term mortality of cardiovascular disease: Experience in National Health and Nutrition Examination Survey (2011-2014)

BACKGROUND

Cardiovascular disease (CVD) is a constellation of heart, brain, and peripheral vascular diseases with common soil hypothesis of etiology, and its subtypes have been well-established in terms of the albumin-mortality association. However, the association between albumin and the mortality of CVD as a whole remains poorly understood, especially the non-linear association. We aimed to investigate the association of albumin levels with long-term mortality of CVD as a whole.

MATERIALS AND METHODS

This study included all CVD patients who participated in the National Health and Nutrition Examination Survey (NHANES 2011-2014). CVD was defined as coronary heart disease, stroke, heart failure, or any combination of these two or three diseases. Serum albumin was tertile partitioned: tertile 1, <4.1; tertile 2, 4.1-4.3; and tertile 3, >4.3 g/dl. COX proportional hazards model was used to assess the association between the serum albumin levels and CVD mortality. Restricted cubic spline (RCS) curves were used to explore the non-linear relationship.

RESULTS

A total of 1,070 patients with CVD were included in the analysis, of which 156 deaths occurred during a median 34 months of follow-up. On a continuous scale, per 1 g/dl albumin decrease was associated with an adjusted HR (95% CI) of 3.85 (2.38-6.25). On a categorical scale, as compared with tertile 3, the multivariable adjusted hazard ratio (95% CI) was 1.42 (0.74-2.71) for the tertile 2, and 2.24 (1.20-4.16) for the tertile 1, respectively, with respect to mortality. RCS curve analysis revealed a J-shaped association between albumin and CVD mortality.

CONCLUSION

A J-shaped association between low serum albumin levels and increased long-term mortality of CVD has been revealed. This J-shaped association's implications for CVD prevention and treatment are deserving of being further studied.

Low serum albumin: A neglected predictor in patients with cardiovascular disease

Albumin, the most abundant circulating protein in blood, is an essential protein which binds and transports various drugs and substances, maintains the oncotic pressure of blood and influences the physiological function of the circulatory system. Albumin also has anti-inflammatory, antioxidant, and antithrombotic properties. Evidence supports albumin's role as a strong predictor of cardiovascular (CV) risk in several patient groups. Its protective role extends to those with coronary artery disease, heart failure, hypertension, atrial fibrillation, peripheral artery disease or ischemic stroke, as well as those undergoing revascularization procedures or with aortic stenosis undergoing transcatheter aortic valve replacement, and patients with congenital heart disease and/or endocarditis. Hypoalbuminemia is a strong prognosticator of increased all-cause and CV mortality according to several cohort studies and meta-analyses in hospitalized and non-hospitalized patients with or without comorbidities. Normalization of albumin levels before discharge lowers mortality risk, compared with hypoalbuminemia before discharge. Modified forms of albumin, such as ischemia modified albumin, also has prognostic value in patients with coronary or peripheral artery disease. When albumin is combined with other risk factors, such as uric acid or C-reactive protein, the prognostic value is enhanced. Although albumin supplementation may be a plausible approach, its efficacy has not been established and in patients with hypoalbuminemia, priority is focused on diagnosing and managing the underlying condition. The CV effects of hypoalbuminemia and relevant issues are considered in this review. Large cohort studies and meta-analyses are tabulated and the physiologic effects of albumin and the deleterious effects of low albumin are pictorially illustrated.

A dose-response meta-analysis to evaluate the relationship between high-density lipoprotein cholesterol and all-cause and cardiovascular disease mortality

PURPOSE

Previous studies have not fully described the relationship between high-density lipoprotein cholesterol (HDL-C) and death risks from all cause and cardiovascular disease (CVD). This study quantitatively evaluates HDL-C-mortality associations.

METHODS

Embase and PubMed databases were searched for relevant articles published up to 1 June 2019. Random-effects models were used to pool relative risks (RRs) and 95% confidence intervals (CIs). We used restricted cubic splines to model the dose-response association.

RESULTS

We identified 32 prospective cohort studies including 369,904 participants and 33,473 total deaths (9426 CVD deaths). Compared to the lowest HDL-C levels, all cause and CVD mortality risks were reduced by 18% (RR 0.82; 95% CI, 0.73-0.93) and 36% (0.64, 0.46-0.89), respectively, for the highest HDL-C levels. All cause and CVD mortality risks were reduced by 15% (0.85, 0.79-0.92) and 23% (0.77, 0.69-0.87), respectively, with each 1 mmol/L increment of HDL-C. We found evidence of nonlinear and negative dose-response associations of HDL-C with all cause and CVD mortality (P_nonlinearity < 0.001), and the lowest death risks from all cause and CVD were observed at approximately 1.34 and 1.55 mmol/L, respectively.

CONCLUSION

HDL-C is inversely associated with all cause and CVD mortality risks under approximately 2.05 and 2.33 mmol/L, respectively. Optimal doses require investigation via clinical practice or high-quality research.

Impact of resting heart rate on cardiovascular mortality according to serum albumin levels in a 24-year follow-up study on a general Japanese population: NIPPON DATA80

BackgroundElevated resting heart rate (RHR) is associated with an increased risk for cardiovascular disease (CVD) and all-cause mortality. However, the findings of cohort studies differed. Thus, the impact of RHR on CVD mortality might be different according to the background of the population. Therefore, we examined the relationship of RHR and CVD mortality according to serum ALB levels in a Japanese general population.MethodsIn total, 8363 individuals without a history of CVD were followed-up for 24.0 years. The participants were divided into four groups according to the quartiles of RHR (Q1-Q4), and they were further classified into the high and low ALB groups based on a median value of 44 g/L. We estimated the multivariable-adjusted hazard ratios (HRs) of CVD mortality in each RHR group based on ALB levels, and the interaction between RHR and ALB groups on CVD mortality was evaluated.ResultsWe found no significant association between RHR and CVD mortality. However, the Q4 of RHR was significantly associated with an increased risk for CVD mortality (HR: 1.27 [95% confidence interval, CI: 1.02-1.57]) in participants with a low ALB level. Meanwhile, the Q4 of RHR was significantly correlated with a decreased risk for CVD morality in those with a high ALB level (HR: 0.61 [95% CI: 0.47-0.79]) after adjusting for covariates. A significant interaction between RHR and ALB for CVD mortality was shown (p<0.001).ConclusionsThe impact of RHR on CVD mortality differed according to ALB levels in a general Japanese population.

Association between Albumin, Total Bilirubin, and Uric Acid Serum Levels and the Risk of Cancer: A Prospective Study in a Korean Population

PURPOSE

In this prospective study, we evaluated the association between the serum levels of antioxidants uric acid (UA), albumin, and total bilirubin and the risk of cancer in a Korean population.

MATERIALS AND METHODS

A total of 15882 subjects were followed up for cancer development and cancer-related death. During the follow-up period, 1619 cancer diagnoses and 617 cancer-related deaths were recorded. Cox proportional regression was performed to calculate the hazard ratio (HR) per standard deviation (SD) increment and 95% confidence interval (CI). The model was adjusted for covariates such as the age, sex, smoking, alcohol consumption, physical activity, education level, body mass index, and family history. Sensitivity analyses using the study subjects with physiological serum levels of each indicator were also performed.

RESULTS

UA levels were positively correlated with cancer risk (HR per SD increment 1.04; 95% CI, 1.01-1.09), and albumin levels were inversely associated with the overall cancer risk (HR, 0.92; 95% CI, 0.88-0.96) and cancer-related death (HR, 0.86; 95% CI, 0.80-0.93). Total bilirubin levels were negatively correlated with the risk of cancer-related death (HR, 0.91; 95% CI, 0.83-0.99). By cancer type, UA was positively associated with prostate cancer, total bilirubin was positively associated with liver cancer, and albumin was inversely associated with lung cancer.

CONCLUSION

The findings of this study support the role of antioxidants in carcinogenesis. Future large-cohort studies are needed to confirm the predictive value of albumin, UA, and total bilirubin levels in each type of cancer.

Serum Albumin and Risks of Stroke and Its Subtypes - The Circulatory Risk in Communities Study (CIRCS)

BACKGROUND

Few studies have investigated the association between serum albumin levels and the risk of stroke subtypes among the general Japanese population.Methods and Results:In this study, 5,071 men and 7,969 women aged 40-74 years, initially free from stroke, coronary artery disease, and kidney and hepatic failure, and residing in 4 Japanese communities completed a baseline risk factor survey between 1985 and 1994. During the 24-year follow-up, 528 men and 553 women experienced stroke. In the entire study cohort, multivariable hazard ratios (HRs) and 95% confidence intervals (CIs) of total stroke, ischemic stroke, and intracerebral hemorrhage for the lowest vs. highest quartiles of serum albumin were 1.45 (1.18-1.77), 1.52 (1.17-1.97), and 1.57 (1.04-2.37), respectively. In men, multivariable HRs (95% CIs) for total stroke, ischemic stroke, and intracerebral hemorrhage in the lowest vs. highest serum albumin quartile were 1.44 (1.07-1.92), 1.48 (1.03-2.11) and 1.71 (0.92-3.18), respectively, whereas in women they were 1.50 (1.13-1.99), 1.63 (1.11-2.39), and 1.56 (0.89-2.74), respectively. Similar inverse associations were observed for each of the ischemic stroke subtypes, but not for subarachnoid hemorrhage.

CONCLUSIONS

Low serum albumin levels were associated with an increased risk of total stroke, ischemic stroke, ischemic stroke subtypes, and intracerebral hemorrhage.

Lower albumin levels are associated with frailty measures, trace elements, and an inflammation marker in a cross-sectional study in Tanushimaru

Background

There is little data on the association between the lower nutrition represented by serum albumin levels and related factors in a general population. The present study aimed to determine whether the albumin level positioned as some kind of biomarker with frailty measures, trace elements, and an inflammation marker.

Methods

In 2018, we performed an epidemiological survey in 1368 subjects who resided in Tanushimaru, Japan, in which we examined the blood chemistry including albumin, trace elements, hormone levels, and carotid ultrasonography. Albumin levels were categorized into 4 groups (G1 [3.2–3.9 mg/dL], G2 [4.0–4.3 mg/dL], G3 [4.4–4.6 mg/dL], and G4 [4.7–5.3 mg/dL]). The participants underwent measurements of handgrip strength and were tested by asking to walk 5 m. Their cognitive functions were evaluated by the mini-mental state examination (MMSE).

Results

Multiple stepwise regression analysis demonstrated that albumin levels were significantly and independently associated with age (inversely), systolic blood pressures, estimated glomerular filtration rate (eGFR), MMSE score, frailty measures (handgrip strength), an inflammation marker (high-sensitivity C-reactive protein), hormones (growth hormone (inversely) and insulin-like growth factor-1), and trace elements (calcium, magnesium, iron, and zinc), with a linear trend.

Conclusions

Lower albumin levels, even in the normal range, were found to be related factors of frailty measures, trace elements, and an inflammation marker in a general population.

Commonly used clinical chemistry tests as mortality predictors: Results from two large cohort studies

Background

The normal ranges for clinical chemistry tests are usually defined by cut-offs given by the distribution in healthy individuals. This approach does however not indicate if individuals outside the normal range are more prone to disease.

Methods

We studied the associations and risk prediction of 11 plasma and serum biomarkers with all-cause mortality in two population-based cohorts: a Swedish cohort (X69) initiated in 1969, and the UK Biobank (UKB) initiated in 2006–2010, with up to 48- and 9-years follow-up, respectively.

Results

In X69 and in UKB, 18,529 and 425,264 individuals were investigated, respectively. During the follow-up time, 14,475 deaths occurred in X69 and 17,116 in UKB. All evaluated tests were associated with mortality in X69 (P<0.0001, except bilirubin P<0.005). For calcium, blood urea nitrogen, bilirubin, hematocrit, uric acid, and iron, U-shaped associations were seen (P<0.0001). For leukocyte count, gamma-glutamyl transferase, alkaline phosphatases and lactate dehydrogenase, linear positive associations were seen, while for albumin the association was negative. Similar associations were seen in UKB. Addition of all biomarkers to a model with classical risk factors improved mortality prediction (delta C-statistics: +0.009 in X69 and +0.023 in UKB, P<0.00001 in both cohorts).

Conclusions

Commonly used clinical chemistry tests were associated with all-cause mortality both in the medium- and long-term perspective, and improved mortality prediction beyond classical risk factors. Since both linear and U-shaped relationships were found, we propose to define the normal range of a clinical chemistry test based on its association with mortality, rather than from the distribution.

Impact of the Serum Level of Albumin and Self-Assessed Chewing Ability on Mortality, QOL, and ADLs for Community-Dwelling Older Adults at the Age of 85: A 15 Year Follow up Study

Quality of life (QOL) and mortality are true endpoints of epidemiological or medical research, especially for community-dwelling older adults. Nutritional status and activities of daily living (ADLs) are associated with QOL and mortality. Good oral health status supports a good nutritional status. The aim of this study was to elucidate the complex structure of these important health-related factors. We surveyed 354 healthy older adults at the age of 85. Nutritional status was evaluated by the serum level of albumin. QOL, ADLs, self-assessed chewing ability, serum albumin level, and mortality during the 15 year follow up period were analyzed. Self-assessed chewing ability was associated with QOL and ADLs. Self-assessed chewing ability for slight-hard foods was associated with mortality in men. However, it was not associated with the serum albumin level. The serum albumin level was associated with mortality in women. These results indicate that maintaining good oral function is not enough. Nutritional instruction in accordance with oral function is indispensable for health promotion in older adults. When planning health promotion strategies for older adults, different strategies are needed for men and women.

Baseline serum albumin and its dynamic change is associated with type 2 diabetes risk: A large cohort study in China

BACKGROUND

The study aimed to investigate the associations of baseline serum albumin level and its dynamic change with type 2 diabetes mellitus (T2DM) risk in a large Chinese cohort study.

METHODS

This cohort study included 30 442 adults without T2DM at first entry, who completed at least one follow-up of annual examinations between 2009 and 2016. Serum albumin level was measured at baseline and at every annual check-up. The dynamic change in serum albumin level (∆ALB) was calculated by subtracting serum albumin level at baseline from that at the last follow-up. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated with Cox regression models.

RESULTS

During 7 years of follow-up, we identified 1634 T2DM events. From the lowest to the highest quartile of serum albumin level, adjusted HRs (95% CI) were 1.00 (reference), 0.96 (0.94, 1.01), 0.98 (0.95, 1.02) and 0.88 (0.85, 0.98), respectively. As compared with stable change in serum albumin (-0.2 ≤ ∆ALB <1.0 g/L), the risk of T2DM increased for ∆ALB < -2.0 g/L (HR 1.44, 95% CI 1.24-1.68) and decreased for ∆ALB ≥3.0 g/L (0.81, 0.68-0.97) after adjusting for potential confounding factors. Restricted cubic splines showed a linear dose-response association between baseline serum albumin level and T2DM risk (P_nonlinearity 0.715) and a nonlinear dose-response association between ∆ALB and T2DM risk (P_nonlinearity 0.011).

CONCLUSIONS

Baseline serum albumin level appears to be inversely associated with T2DM risk. Adults with reduced serum albumin level could be early identified for diabetes risk in clinical practice.

Serum albumin, cardiometabolic and other adverse outcomes: systematic review and meta-analyses of 48 published observational cohort studies involving 1,492,237 participants

Objectives. A general body of evidence suggests that low serum albumin might be associated with increased risk of adverse cardiometabolic outcomes, but findings are divergent. We aimed to quantify associations of serum albumin with the risk of type 2 diabetes (T2D), cardiovascular disease (CVD), all-cause mortality, and other adverse outcomes using a systematic review and meta-analyses of published observational cohort studies. Design. MEDLINE, Embase, Web of Science, and manual search of relevant bibliographies were systematically searched to January 2020. Relative risks (RRs) with 95% confidence intervals (CIs) comparing top versus bottom thirds of serum albumin levels were pooled. Results. Fifty-four articles based on 48 unique observational cohort studies comprising of 1,492,237 participants were eligible. Multivariable adjusted RRs (95% CIs) comparing the top vs bottom third of serum albumin levels were: 1.03 (0.86-1.22) for T2D; 0.60 (0.53-0.67) for CVD; 0.74 (0.66-0.84) for coronary heart disease (CHD); 0.57 (0.36-0.91) for CHD death; 0.76 (0.65-0.87) for myocardial infarction; 0.66 (0.55-0.77) for all-cause mortality; 0.71 (0.61-0.83) for venous thromboembolism; 0.65 (0.48-0.88) for cancer mortality; and 0.62 (0.46-0.84) for fracture. Heterogeneity between contributing studies of T2D was partly explained by sample sizes of studies (p for meta-regression = .035). Conclusions. Elevated levels of serum albumin are associated with reduced risk of vascular outcomes, all-cause mortality, certain cancers, and fracture. Inconsistent findings for T2D may be attributed to selective reporting by studies. Further research is needed to assess any potential causal relevance to these findings and the role of serum albumin concentrations in disease prevention.Systematic review registration: PROSPERO 2019: CRD42019125869.

New Insights About Albumin and Liver Disease

Decompensated liver cirrhosis has a dismal prognosis, with an overall survival of 2-4 years, which is worse than for many oncological diseases. Albumin is an important tool in the management of patients with cirrhosis, since it decreases for less than half the risk for post-paracentesis cardiocirculatory dysfunction and mortality associated with spontaneous bacterial infection, as well as, it triplicates the response to terlipressin in patients with hepatorenal syndrome. Recently, research on albumin has been a hot topic, with important new insights such as the characterization of the pleiotropic effects of albumin (which surpass its oncotic properties) and the concept of effective albumin concentration. In fact, patients with liver cirrhosis present posttranslational modifications on albumin that compromises its function. Those modified albumin forms were proved to have prognostic value and its knowledge may change the paradigm of albumin treatment. In this review, we critically summarize the latest evidence on the potential benefits of albumin in patients with end-stage liver disease.

Critical appraisal of the role of serum albumin in cardiovascular disease

Concentration of serum albumin (SA), a multifunctional circulatory protein, is influenced by several factors, including its synthesis rate, catabolism rate, extravascular distribution, and exogenous loss. Moreover, both nutritional status and systemic inflammation affect the synthesis of SA. Determining SA concentration aids in risk prediction in various clinical settings. It is of interest to understand the prognostic value of SA in the full spectrum of cardiovascular disease (CVD) in the era of newly developed pharmacological and interventional treatments. Proper interpretation of SA in addition to established risk factors potentially provides a better risk discrimination and thereby presents an option to modify therapeutic strategies accordingly. In this narrative review, we summarize the basic features of SA and its associated physiological functions contributing to its prognostic impacts on CVD. Finally, we discuss the prognostic role of SA in CVDs based on existing evidence.