In addition to malnutrition and renal function impairment, anemia is associated with hyponatremia in the elderly

Uric acid en route to gout

Gout and hyperuricemia (HU) have generated immense attention due to increased prevalence. Gout is a multifactorial metabolic and inflammatory disease that occurs when increased uric acid (UA) induce HU resulting in monosodium urate (MSU) crystal deposition in joints. However, gout pathogenesis does not always involve these events and HU does not always cause a gout flare. Treatment with UA-lowering therapeutics may not prevent or reduce the incidence of gout flare or gout-associated comorbidities. UA exhibits both pro- and anti-inflammation functions in gout pathogenesis. HU and gout share mechanistic and metabolic connections at a systematic level, as shown by studies on associated comorbidities. Recent studies on the interplay between UA, HU, MSU and gout as well as the development of HU and gout in association with metabolic syndromes, non-alcoholic fatty liver disease (NAFLD), and cardiovascular, renal and cerebrovascular diseases are discussed. This review examines current and potential therapeutic regimens and illuminates the journey from disrupted UA to gout.

High Blood Uric Acid Is Associated With Reduced Risks of Mild Cognitive Impairment Among Older Adults in China: A 9-Year Prospective Cohort Study

Background: It remains unsolved that whether blood uric acid (UA) is a neuroprotective or neurotoxic agent. This study aimed to evaluate the longitudinal association of blood UA with mild cognitive impairment (MCI) among older adults in China.

Methods: A total of 3,103 older adults (aged 65+ years) free of MCI at baseline were included from the Healthy Aging and Biomarkers Cohort Study (HABCS). Blood UA level was determined by the uricase colorimetry assay and analyzed as both continuous and categorical (by quartile) variables. Global cognition was assessed using the Mini-Mental State Examination four times between 2008 and 2017, with a score below 24 being considered as MCI. Cox proportional hazards models were used to examine the associations.

Results: During a 9-year follow-up, 486 (15.7%) participants developed MCI. After adjustment for all covariates, higher UA had a dose-response association with a lower risk of MCI (all P_{for  trend} < 0.05). Participants in the highest UA quartile group had a reduced risk [hazard ratio (HR), 0.73; 95% (CI): 0.55–0.96] of MCI, compared with those in the lowest quartile group. The associations were still robust even when considering death as a competing risk. Subgroup analyses revealed that these associations were statistically significant in younger older adults (65–79 years) and those without hyperuricemia. Similar significant associations were observed when treating UA as a continuous variable.

Conclusions: High blood UA level is associated with reduced risks of MCI among Chinese older adults, highlighting the potential of managing UA in daily life for maintaining late-life cognition.

Hyponatremia is a Prognostic Factor in Patients Receiving Nutrition Support

BACKGROUND

Hyponatremia, the most common electrolyte disorder, has been reported to be related to increased mortality. However, the association between hyponatremia and prognoses remains unclear in patients with nutrition support team (NST) intervention. This study aimed to determine the prevalence of abnormal serum sodium levels, its relation to patient data, and the impact of hyponatremia on prognosis.

METHODS

Patients who received nutrition support at Tokushima University Hospital for the first time and whose serum sodium levels were measured at the start of NST intervention were enrolled. Patients were classified into three groups according to their serum Na levels at the start of NST intervention: hyponatremia group, normonatremia group, and hypernatremia group.

RESULTS

In the hyponatremia group compared to the normonatremia group, body weight and body mass index were significantly lower. C-reactive protein levels and urea nitrogen/creatinine ratios were significantly higher. Meanwhile, there was no significant difference in the estimated glomerular filtration rate among the groups. The prevalence of malnutrition and anemia were the highest in the hyponatremia group. The 3-year survival rate was approximately 45% in the hyponatremia group, which was the lowest of all three groups. The mortality risk ratio of the hyponatremia group to the normonatremia group was 2.29.

CONCLUSIONS

Hyponatremia in NST intervention patients is an independent prognostic predictor. Therefore, adding an assessment of serum sodium at the beginning of NST intervention can identify patients at high risk at an early stage and may improve the quality of NST activity.

Contribution of SLC22A12 on hypouricemia and its clinical significance for screening purposes

Differentiating between inherited renal hypouricemia and transient hypouricemic status is challenging. Here, we aimed to describe the genetic background of hypouricemia patients using whole-exome sequencing (WES) and assess the feasibility for genetic diagnosis using two founder variants in primary screening. We selected all cases (N = 31) with extreme hypouricemia (<1.3 mg/dl) from a Korean urban cohort of 179,381 subjects without underlying conditions. WES and corresponding downstream analyses were performed for the discovery of rare causal variants for hypouricemia. Two known recessive variants within SLC22A12 (p.Trp258*, pArg90His) were identified in 24 out of 31 subjects (77.4%). In an independent cohort, we identified 50 individuals with hypouricemia and genotyped the p.Trp258* and p.Arg90His variants; 47 of the 50 (94%) hypouricemia cases were explained by only two mutations. Four novel coding variants in SLC22A12, p.Asn136Lys, p.Thr225Lys, p.Arg284Gln, and p.Glu429Lys, were additionally identified. In silico studies predict these as pathogenic variants. This is the first study to show the value of genetic diagnostic screening for hypouricemia in the clinical setting. Screening of just two ethnic-specific variants (p.Trp258* and p.Arg90His) identified 87.7% (71/81) of Korean patients with monogenic hypouricemia. Early genetic identification of constitutive hypouricemia may prevent acute kidney injury by avoidance of dehydration and excessive exercise.

Hyponatremia and mortality among very elderly residents in a geriatric health service facility

INTRODUCTION

Hyponatremia is common among elderly patients. This study aimed to examine the prognostic value of hyponatremia among elderly residents in a geriatric facility.

METHODS

We retrospectively examined the association between serum sodium levels and mortality among 118 residents (82% female, mean age 85.5 years) in a single geriatric health service facility. We defined hyponatremia as Na < 135 mEq/L. On the basis of single measurements of serum sodium at periodic examinations, the patients were divided into hyponatremia and non-hyponatremia groups. Multivariable Cox proportional hazards models were used to evaluate the effect of hyponatremia on mortality from May 2005 to April 2007.

RESULTS

Thirty-three patients (28%) had hyponatremia. Over a 1-year follow-up period, the cumulative survival rate was significantly lower in patients with hyponatremia than in those without hyponatremia. In a multivariate analysis, including traditional risk factors for death, hyponatremia was associated with an increased mortality risk (adjusted hazard ratio 2.73; 95% confidence interval 1.01-5.16; p = 0.047).

CONCLUSIONS

Hyponatremia is common and is a predictor of mortality in the near future among very elderly residents of a geriatric facility.

Factors Associated with Anemia in the Institutionalized Elderly

As a common problem in long-term care facilities (LTCFs), anemia affects 25–63% of the elderly. The aim of the present study was to describe the prevalence and characteristics of anemia and its associated factors in the institutionalized elderly. The cross-sectional study was carried out with three hundred thirteen individuals aged ≥ 60 years, of both genders, living in long-term care facilities for the elderly in Salvador, Bahia, Brazil. Poisson regression (PR) with robust variance estimates was used to assess the factors related to anemia. The prevalence of anemia was 38%. Mild anemia was predominant in both genders (male: 26.8%; female: 21.1%), as normocytic and normochromic anemia, with no anisocytosis (69.75%). Anemia was associated with thinness (PR: 1.68; 95% CI: 1.04–2.72) and with moderate (PR: 1.98; 95% CI: 1.07–3.63) and total (PR: 2.61; 95% CI: 1.34–5.07) dependence in the final model. Severe dependence exhibited borderline significance (PR: 1.94; 95% CI: 1.00–3.77). The prevalence of anemia was high in the institutionalized elderly in both genders, with characteristics suggesting chronic diseases as the causal factor, and the frequency of occurrence was higher in thinness elderly with moderate to total dependence.

The risk of hyponatremia with desmopressin use for nocturnal polyuria

BACKGROUND

Desmopressin is used for treating nocturnal polyuria, but hyponatremia is an associated concern in the elderly due to impaired urinary dilution. This study was undertaken to characterize hyponatremia occurring in adults using desmopressin for nocturnal polyuria.

METHODS

Data from 172 patients who were prescribed desmopressin for nocturnal polyuria at a urology clinic from September 2010 through February 2013 were retrospectively analyzed. Demographic and laboratory parameters were investigated to examine the risk factors for desmopressin-associated hyponatremia.

RESULTS

The average follow-up serum sodium measured 21 ± 22 days after using desmopressin was 138 ± 5 mmol/l. Hyponatremia (<135 mmol/l) was found in 24 patients (14%), and it was severe in 7 (<126 mmol/l). In the hyponatremic patients, serum sodium decreased by 11 ± 6 mmol/l. Patients with hyponatremia were older than those with normonatremia (78 ± 7 vs. 68 ± 9 years, p < 0.0001). The presence of either hyponatremia-predisposing comorbidities or concurrent medications was associated with hyponatremia. Patients with hyponatremia had lower basal hemoglobin (11 ± 2 vs. 13 ± 2 g/dl, p < 0.001) and serum sodium (139 ± 2 vs. 140 ± 2 mmol/l, p < 0.05) than those with normonatremia. Multivariate logistic regression after adjustment for basal serum sodium showed that advanced age (OR 1.15; 95% CI 1.03-1.27) and lower hemoglobin level (OR 0.64; 95% CI 0.43-0.94) were independently associated with hyponatremia.

CONCLUSION

Hyponatremia is not infrequently associated with desmopressin use. Those with advanced age (≥65 years) and lower hemoglobin are at risk of desmopressin-associated hyponatremia and need to be carefully monitored.

Selenium is inversely associated with interleukin-6 in the elderly

BACKGROUND

Selenium is an essential trace element with antioxidant property. Decreased serum selenium concentration with aging had been found in previous report. In this study, we aim to investigate the association between serum selenium and the inflammatory cytokine interleukin-6 in the elderly living in long-term care facilities in Taiwan.

MATERIALS AND METHODS

A total of 336 subjects aged 65 years and older (range of age: 65 - 101 years) were recruited from eight long-term care facilities in 2002-2003. Baseline characteristics, anthropometric indices, and biochemical data were obtained. Selenium deficiency was defined as serum selenium concentration < 80 μg/L. Multiple logistic and linear regression analyses were used to examine the relationships between selenium deficiency and interleukin-6 (divided into quartiles).

RESULTS

The prevalence of selenium deficiency was 35.6% in men and 43.2% in women, respectively. After adjusting for potential confounders using multiple logistic regression analysis, interleukin-6 quartiles were significantly associated with selenium deficiency. Compared to the interleukin-6 quartile I, the adjusted odds ratios of having selenium deficiency for interleukin-6 quartile II, III, IV were 1.00(0.50~2.01), 1.24 (0.62~2.50), and 2.35(1.15~4.83), respectively. The increasing odds ratios for selenium deficiency in higher interleukin-6 quartiles revealed dose-response effects (p < 0.05). Moreover, multiple linear regression analysis showed that serum selenium was significantly inversely associated with interleukin-6 after adjusting for potential confounders.

CONCLUSIONS

Serum selenium was inversely associated with inflammatory cytokine interleukin-6 among elderly living in long-term care facilities in Taiwan. Monitoring serum selenium should be considered in these institutionalized elderly.