Predictors of cancer mortality in elderly subjects

The association between serum liver enzymes and cancer mortality

Interpreting levels of liver enzymes is often challenging because they may be influenced by metabolic processes beyond the liver. Given their pathophysiologic roles in inflammation and oxidative stress, higher levels of these enzymes may be associated with increased risk of mortality. However, studies have found inconsistent results. Thus, we examined the association of liver enzymes levels with cancer mortality in the general US adult population. We used the US National Health and Nutrition Examination Survey from 1999 to 2016. Kaplan-Meier survival curve comparisons were examined across quartiles of liver enzymes. Cox proportional hazards models were built to examine the relationship between cancer mortality and liver enzymes quartiles without and with adjustment for potential confounding factors. During the 338,882 person-years follow-up, 1059 participants had cancer-related deaths. There was a nonlinear U-shaped relationship between serum alanine and aspartate aminotransferase (ALT and AST) levels and cancer mortality. There was no relationship between cancer mortality and gamma-glutamyltransferase (GGT); however, each 10 IU/L increase in GGT after median was associated with 1% higher mortality risk (HR = 1.01; 95% CI = 1.00, 1.02; P = 0.001). Only subjects with high levels of alkaline phosphatase (ALP) had higher cancer mortality (HR = 1.63; 95CI = 1.30, 2.05; P < 0.001 and HR = 1.52; 95%CI = 1.20, 1.94; P = 0.001, respectively). Only the lowest and highest serum ALT and AST levels are associated with increased cancer mortality. For ALP, the relationship is present at higher levels. The association with GGT was not robust to different analyses. The mechanisms underlying the observed relationships need further exploration.

High serum uric acid concentration predicts poor survival in patients with breast cancer

BACKGROUND

Uric acid is a product of purine metabolism. Recently, uric acid has gained much attraction in cancer. In this study, we aim to investigate the clinicopathological and prognostic significance of serum uric acid concentration in breast cancer patients.

METHODS

A total of 443 female patients with histopathologically diagnosed breast cancer were included. After a mean follow-up time of 56months, survival was analysed using the Kaplan-Meier method. To further evaluate the prognostic significance of uric acid concentrations, univariate and multivariate Cox regression analyses were applied.

RESULTS

Of the clinicopathological parameters, uric acid concentration was associated with age, body mass index, ER status and PR status. Univariate analysis identified that patients with increased uric acid concentration had a significantly inferior overall survival (HR 2.13, 95% CI 1.15-3.94, p=0.016). In multivariate analysis, we found that high uric acid concentration is an independent prognostic factor predicting death, but insufficient to predict local relapse or distant metastasis. Kaplan-Meier analysis indicated that high uric acid concentration is related to the poor overall survival (p=0.013).

CONCLUSIONS

High uric acid concentration predicts poor survival in patients with breast cancer, and might serve as a potential marker for appropriate management of breast cancer patients.

Investigation of risk factors for mortality in aged guide dogs: A retrospective cohort study

The overall median lifespan of domestic dogs has been estimated to 9-12 years, but little is known about risk factors for mortality in aged and a priori healthy dogs. The objective of this retrospective cohort study was to determine which characteristics are associated with mortality in aged and a priori healthy guide dogs, in a retrospective cohort study of 116 guide dogs followed from a systematic geriatric examination at the age of 8-10 years old. A geriatric grid collected the clinical data and usual biological parameters were measured at the time of examination. Univariate (Kaplan-Meier estimates) and multivariable (Cox proportional hazard model) survival analyses were used to assess the associations with time to all-cause death. The majority of dogs were Golden Retrievers (n=48) and Labrador Retrievers (n=27). Median age at geriatric examination was 8.9 years. A total of 76 dogs died during follow-up, leading to a median survival time from geriatric examination of 4.4 years. After adjustment for demographic and biological variables, an increased alanine amionotransferase level (adjusted Hazard Ratio (adjusted HR), 6.2; 95% confidence interval [95%CI], 2.0-19.0; P<0.01), presenting skin nodules (adjusted HR, 1.9; 95% CI, 1.0-3.4; P=0.04), and not being a Labrador Retriever (adjusted HR, 3.3; 95%CI, 1.4-10; P<0.01) were independently associated with a shorter time to death. This study documents independent associations of alanine aminotransferase level, skin nodules and breed with mortality in aged guide dogs. These results may be useful for preventive medical care when conducting a geriatric examination in working dogs.

Serum Uric Acid Increases Risk of Cancer Incidence and Mortality: A Systematic Review and Meta-Analysis

SUA is a potent antioxidant and thus may play a protective role against cancer. Many epidemiological studies have investigated this hypothesis but provided inconsistent and inconclusive findings. We aimed to precisely elucidate the association between SUA levels and cancer by pooling all available publications. Totally, 5 independent studies with 456,053 subjects and 12 with 632,472 subjects were identified after a comprehensive literature screening from PubMed, Embase, and Web of Science. The pooled RRs showed that individuals with high SUA levels were at an increased risk of total cancer incidence (RR = 1.03, 95% CI 1.01–1.05, P = 0.007). Positive association between high SUA levels and total cancer incidence was observed in males but not females (for men: RR = 1.05, 95% CI 1.02–1.08, P = 0.002; for women, RR = 1.01, 95% CI 0.98–1.04, P = 0.512). Besides, high SUA levels were associated with an elevated risk of total cancer mortality (RR = 1.17, 95% CI 1.04–1.32, P = 0.010), particularly in females (RR = 1.25, 95% CI 1.07–1.45, P = 0.004). The study suggests that high SUA levels increase the risk of total cancer incidence and mortality. The data do not support the hypothesis of a protective role of SUA in cancer.

Increased Risk of Cancer in relation to Gout: A Review of Three Prospective Cohort Studies with 50,358 Subjects

Gout is a common inflammatory disease characterized by acute arthritis and hyperuricemia. A number of epidemiological studies have suggested the critical role of gout in carcinogenesis. The aim of this study was to estimate the association between gout and cancer risk by meta-analysis of all relevant studies published to date. A comprehensive literature search in PubMed and Embase databases from their inception up to July 1, 2014, was performed to identify eligible studies. The strength for relationship between gout and the risk of different cancers was evaluated by calculating pooled relative risks (RRs) with 95% confidence intervals (95% CIs). All analyses were carried out by STATA 12.0 software. Gout patients were at an increased risk of cancer, particularly urological cancers, digestive system cancers, and lung cancer. No such significant association between gout and the risk of breast or brain cancers was observed. Sensitivity analysis did not materially alter the pooled results. Gout is a risk factor of cancer, particularly that of urological cancers, digestive system cancers, and lung cancer. The pooled data further support the hypothesis of a link between gout and carcinogenesis.

Inhibition of xanthine oxidase reduces wasting and improves outcome in a rat model of cancer cachexia

Cachexia is a common co-morbidity in cancer occurring in up to 80% of patients depending on the type of cancer. Uric acid (UA), the end-product of the purine metabolism, is elevated in cachexia due to tissue wasting and upregulated xanthine oxidase (XO) activity. High serum UA levels indicate increased XO-dependent production of oxygen free radicals (reactive oxygen species; ROS) and correlate with metabolic illness and poor survival. We hypothesized that XO-inhibition might reduce inflammatory signals accounting for tissue wasting and improve survival in experimental cancer cachexia. Animals were inoculated intraperitoneally with AH-130 hepatoma cells and treated with two XO-inhibitors: allopurinol [Allo, low (LD) and high dose (HD) 4 and 40 mg/kg/d] and its more effective active metabolite oxypurinol (Oxy, 4 and 40 mg/kg/d) or placebo for 15 days. Weight loss and tissue wasting of both fat and lean tissue (assessed by NMR-scanning) was reduced by both LD and HD Allo and LD-Oxy, but not by HD-Oxy. A robust induction of XO-activity for generation of reactive oxygen species was seen in the placebo group (assessed by electron paramagnetic spectroscopy), which was reduced by XO-inhibition. Increased ROS induced cytokine signaling, proteolytic activity and tissue degradation were all attenuated by XO inhibition. Survival was significantly and dose dependently improved. Food intake and spontaneous locomotor activity were higher, indicating a higher quality of life. Inhibition of XO can reduce tissue wasting and improve survival in cancer cachexia and clearly clinical studies are needed.

Elevated serum alanine aminotransferase and gamma-glutamyltransferase and mortality in the United States population

BACKGROUND & AIMS

Elevated serum alanine aminotransferase (ALT) and gamma-glutamyltransferase (GGT) activities are markers of liver injury, but may also be associated with other diseases and death. In a prospective, national, population-based sample, we examined whether elevated ALT and GGT were associated with increased risk of all-cause and disease-specific mortality.

METHODS

Death certificate-based 12-year mortality was analyzed among 14,950 adult participants in the third US National Health and Nutrition Examination Survey, 1988-1994, who were negative for markers of viral hepatitis B and C. Abnormal ALT was defined as >30 U/L in men or >19 U/L in women, and abnormal GGT as >51 U/L in men or >33 U/L in women.

RESULTS

Cumulative mortality was 13.9% from all causes, including 4.2% from cardiovascular disease, 4.2% from neoplasms, 0.44% from diabetes, and 0.13% from liver disease. In multivariate-adjusted analyses, elevated ALT was not associated with all-cause mortality (hazard ratio [HR], 1.2; 95% confidence interval [CI], 0.88-1.6). ALT elevation was associated with deaths from liver disease (HR, 8.2; 95% CI, 2.1-31.9), but not from cardiovascular disease (HR, 0.90; 95% CI, 0.56-1.4), neoplasms (HR, 1.0; 95% CI, 0.65-1.5), or diabetes (HR, 2.4; 95% CI, 0.65-9.1). All-cause mortality increased with elevated GGT (HR, 1.5; 95% CI, 1.2-1.8), as did mortality from liver disease (HR, 13.0; 95% CI, 2.4-71.5), neoplasms (HR, 1.5; 95% CI, 1.01-2.2), and diabetes (HR, 3.3; 95% CI, 1.4-7.6), but not from cardiovascular disease (HR, 1.3; 95% CI, 0.80-2.0).

CONCLUSIONS

In the US population, elevated GGT was associated with mortality from all causes, liver disease, cancer, and diabetes, while ALT was associated only with liver disease mortality.

Prognostic value of serum liver enzymes levels in type 2 diabetic patients

BACKGROUND

Elevated liver enzymes are associated with cardiovascular disease, while their relationship with cancer-related mortality has not been assessed so far in diabetic patients.

METHODS

An observational cohort study was performed on a consecutive series of 1952 type 2 diabetic patients. The association of liver enzymes with all-cause and cause-specific mortality was assessed. Information on all-cause mortality was obtained by the City of Florence Registry Office.

RESULTS

The average duration of follow-up was 6.4 +/- 2.7 years. Over that period, 362 deaths were recorded (26.9%), with a yearly mortality rate of 4.2%. Age- and sex-adjusted HR of all-cause mortality for gamma glutamyl-transpeptidase (gamma-GT) gamma-GT > 40 U/l was 1.610 [1.245-2.082]. An increased cardiovascular mortality rate was observed in patients with elevation of gamma-GT, and gamma-GT and/or alanine aminotransferase (ALT), when compared with the rest of the sample (15.3 vs 10.8%, p < 0.05; and 15.2 vs 10.7%, p < 0.05, respectively). Similar results were observed when considering cancer-related mortality. The association of higher gamma-GT levels with all-cause, cardiovascular, and cancer-related mortality was confirmed at a multivariate analysis after adjustment for potential confounders.

CONCLUSIONS

The present study shows that, in type 2 diabetic patients, higher gamma-GT, but not ALT, is associated with increased mortality for cardiovascular disease and malignancies.

Uric acid as a prognostic factor for survival time: a prospective cohort study of terminally ill cancer patients

The aim of this prospective cohort study was to determine whether serum uric acid level is useful as a predictor of survival in terminally ill cancer patients. One hundred eighteen terminally ill cancer patients, including 63 (53.4%) males, were categorized into four groups by serum uric acid levels and followed up until death or to the end of the study. Cox's proportional hazard model was adopted to evaluate the joint effect of some clinicobiological variables on survival. From an initial model containing 51 variables, a final parsimonious model was obtained by means of a stepwise method. Repetitive dispersion analysis was performed for serum uric acid level in 39 subjects for 3 weeks until death. During the study period, 113 (95.76%) subjects expired, and the median survival time was 14 days. In univariate analysis, survival time of the fourth highest group (> or =7.2mg/dL) was significantly shorter than that of the others (hazard ratio (HR)=2.784, P<0.001). After adjustment for low performance status, moderate to severe pain, prolonged prothrombin time, hypocholesterolemia, and high lactate dehydrogenase (LDH) level, high serum uric acid level (> or =7.2mg/dL) was significantly and independently associated with short survival time (HR=2.637, P=0.001). Serum uric acid levels were also significantly increased between the first and the second week before death. These findings suggest that serum uric acid level can be useful in predicting life expectancy in terminally ill cancer patients.

Patterns and Predictors of Smoking Cessation in an Elderly Cohort

OBJECTIVES

To identify subject characteristics that predict smoking cessation and describe patterns of cessation and recidivism in a cohort of elderly smokers.

DESIGN

Prospective cohort study.

SETTING

Piedmont region, North Carolina.

PARTICIPANTS

Five hundred seventy-three subjects enrolled in the North Carolina Established Populations for Epidemiologic Studies of the Elderly who responded "yes" to question 179 on the baseline survey (Do you smoke cigarettes regularly now?) and survived at least 3 years, until the next in-person follow-up (1989/90). Subjects were classified as quitters (n=100) or nonquitters (n=473) based on subsequent smoking behavior.

MEASUREMENTS

Reported smoking behavior, demographic characteristics of the smokers at baseline or subsequent interviews, 7-year mortality.

RESULTS

After controlling for all characteristics studied, subjects who quit smoking were more likely to be female (P=.03) and showed a trend toward greater likelihood of a recent cancer diagnosis (P=.11). Recidivism was observed in only 16% (19/119) of subjects who reported no smoking in 1989/90. The percentage of subjects who died during 7 years of follow-up was 44.0% of quitters, compared with 51.6% of nonquitters. Smoking cessation was not associated with a statistically significant decrease in risk of death after controlling for other variables (odds ratio=0.78, 95% confidence interval=0.48-1.26).

CONCLUSION

Smoking cessation in this elderly cohort was associated with different subject characteristics from those that predict successful cessation in younger populations, suggesting that older smokers may have unique reasons to stop smoking. Further study is needed to assess potential motives and benefits associated with smoking cessation at an advanced age.

Heritability of biochemical kidney markers and relation to survival in the elderly--results from a Danish population-based twin study

BACKGROUND AND AIM

We performed a twin study to assess the relative contribution of genetic and environmental factors to serum levels of urea, creatinine, urate and sodium in a population of 688 elderly twins (73-95 years). Furthermore, we tested the association between these biochemical values and mortality to examine the consequence of an abnormal biochemical kidney parameter in an aging population.

RESULTS

A third to a half of the variation in the biochemical kidney tests is due to genetic factors except for creatinine in males. Survival analysis show that all four parameters influence mortality and values below reference interval for urea and urate have a more pronounced impact on survival [hazard ratios (95% confidence interval): 2.32 (1.03-5.26) and 3.56 (1.46-8.69), respectively] than values above [1.20 (0.87-1.64) and 1.50 (1.11-2.02), respectively]. Increased creatinine (above 130 micromol/l) and decreased sodium (below 136 mmol/l) also have a significant impact on survival with hazard ratios on 1.83 (1.13-2.95) and 1.56 (1.22-1.99), respectively. Between 5% and 44% of the measured values are outside the established reference interval.

CONCLUSION

This study provides evidence for the importance of genetic factors in determining the biochemical kidney parameters in an aging population. Furthermore, our data shows that abnormal kidney parameters are common in older adults and results in a significant increase in mortality risk.

Oxidant stress and glioblastoma multiforme risk: serum antioxidants, gamma-glutamyl transpeptidase, and ferritin

Case-control studies of serum antioxidants are difficult to interpret, because antioxidants may be altered by the disease under study. However, because glioblastoma multiforme (GBM) is a relatively rare disease, a cohort study would require a large sample observed for many years. In the present case-control pilot study (34 cases and 35 controls), we evaluated the association between serum levels of ascorbic acid (AA) and alpha- and gamma-tocopherol (alpha-T and gamma-T) measured before diagnostic surgery. To control for influence of GBM on serum AA, alpha-T, and gamma-T, we adjusted for oxidant stress indexes (gamma-glutamyl transpeptidase and uric acid) and an acute-phase response index (serum ferritin). When adjusted, AA is inversely related to GBM (p for trend = 0.007). In addition, AA interacts with alpha-T to further reduce GBM risk (test for interaction, p = 0.04). gamma-T is not associated with GBM (p = 0.71). However, gamma-glutamyl transpeptidase (p = 0.004), coenzyme Q (p = 0.01), and ferritin (p = 0.009) are positively and uric acid (p = 0.000) is negatively related to GBM. We conclude that 1) AA and alpha-T are jointly related to GBM after adjustment for GBM-produced oxidant stress and 2) there is a strong association between the presence of GBM and oxidant stress.