Clinical features, outcome and cost of hyponatremia-associated admission and hospitalization in elderly and very elderly patients: a single-center experience in Turkey

Purpose

Hyponatremia is a common electrolyte disorder in hospitalized patients. Clinical features, outcome and cost of hyponatremia-associated admission and hospitalization in elderly and very elderly patients are not well known.

Methods

Elderly (>64 years) patients admitted to the emergency department (ED) and hospitalized between January 1, 2010, and December 31, 2010, were evaluated. Hyponatremia was defined as serum sodium level below 135 mmol/L. Hyponatremic patients were divided into two groups: group 1 (n = 150, 65–74 years old) and group 2 (n = 103, >74 years old).

Results

A total of 4,960 patients above 65 years of age admitted to ED and hospitalized were included. Prevalence of ED in group 1 and group 2 was 4.1 % (150/3,651) and 7.8 % (103/1,309), respectively (p < 0.001). Vomiting and diarrhea were the most important complaints. A total of 111 (43.8 %) patients were being treated with renin–angiotensin system (RAS) blockers. Mortality, morbidity and hospital cost increased in parallel to decrease in serum Na⁺ level and increase in age. Group 2 subjects had not only higher intensive care need (p < 0.01) and mortality rates (p < 0.01), but also higher hospital cost burden (p < 0.05) compared to group 1. Alzheimer’s disease was one of the most common co-morbidity in patients, particularly in group 2 (5.3 % vs. 21.3 %, p < 0.001).

Conclusion

Hyponatremia-associated hospitalization is an important and potentially lethal condition in elderly and very elderly patients. Clinicians should be careful when prescribing RAS blockers and diuretics in elderly patients.     

Aminoguanidine prevents testicular damage–induced‐2,3,7,8‐tetrachlorodibenzo‐p‐dioxin (TCDD) in male rats

In this study, it was aimed to determinate protective effects of aminoguanidine (AG) against reproductive toxicity caused by 2,3,7,8‐tetrachlorodibenzo‐p‐dioxin (TCDD), an environmental contaminant. Thirty‐two rats were equally divided into four groups; the first group was kept as control and given corn oil as carrier. In second and third groups, TCDD and AG were orally administered at the dose of 2 μg kg^?1 per week and 100 mg kg^?1 per day for 45 days, respectively. In fourth group, TCDD and AG were given together at the same doses. Although TCDD significantly increased the formation of TBARS, it caused a significant decline in the levels of GSH, CAT, GPx and SOD in rats. On the other hand, AG, given together TCDD, reversed TCDD effects on TBARS SOD, GSH, GPx and CAT. In addition, sperm characteristics negatively affected and histopathological deformation occurred with TCDD exposure. However, AG treatment partly prevented these toxic effects of TCDD on spermatological parameters and histopathological changes. In conclusion, TCDD exposure induces testicular damage (oxidative stress, histopathological damage and sperm parameters), and AG treatment reversed TCDD‐induced testicular damage in rats. Thus, AG may be useful for the prevention and treatment of TCDD‐induced male infertility problems.     

How attentional boost interacts with reward: the effect of dopaminergic medications in Parkinson's disease

There is widespread evidence that dopamine is implicated in the regulation of reward and salience. However, it is less known how these processes interact with attention and recognition memory. To explore this question, we used the attentional boost test in patients with Parkinson's disease (PD) before and after the administration of dopaminergic medications. Participants performed a visual letter detection task (remembering rewarded target letters and ignoring distractor letters) while also viewing a series of photos of natural and urban scenes in the background of the letters. The aim of the game was to retrieve the target letter after each trial and to win as much virtual money as possible. The recognition of background scenes was not rewarded. We enrolled 26 drug‐naïve, newly diagnosed patients with PD and 25 healthy controls who were evaluated at baseline and follow‐up. Patients with PD received dopamine agonists (pramipexole, ropinirole, rotigotine) during the 12‐week follow‐up period. At baseline, we found intact attentional boost in patients with PD: they were able to recognize target‐associated scenes similarly to controls. At follow‐up, patients with PD outperformed controls for both target‐ and distractor‐associated scenes, but not when scenes were presented without letters. The alerting, orienting and executive components of attention were intact in PD. Enhanced attentional boost was replicated in a smaller group of patients with PD (n = 15) receiving l ‐3,4‐dihydroxyphenylalanine (L‐DOPA). These results suggest that dopaminergic medications facilitate attentional boost for background information regardless of whether the central task (letter detection) is rewarded or not.     

The epigenetic effect of nicotine on dopamine D1 receptor expression in rat prefrontal cortex

Nicotine is a highly addictive drug and exerts its effect partially through causing dopamine release, thereby increasing intrasynaptic dopamine levels in the brain reward systems. Dopaine D1 receptor (DRD1) mRNAs and receptors are localized in reward‐related brain regions, which receive cholinergic input. The aim of this study is to evaluate whether nicotine administration affects the expression of DRD1s, and if so, whether epigenetic mechanisms, such as histone acetylation, are involved. Twenty Male Sprague Dawley rats received nicotine (0.4 mg/kg/day, s.c.) or saline injections for 15 days. After nicotine/saline treatment, rats were perfused with saline; prefrontal cortex (PFC), corpus striatum (STR), and ventral tegmental area (VTA) were dissected. Homogenates were divided into two parts for total RNA isolation and histone H4 acetylation studies. DRD1 mRNA expression was significantly higher in the PFC of the nicotine‐treated group compared with controls; similar trends were observed in the VTA and STR. To study epigenetic regulation, the 2kb upstream region of the DRD1 gene promoter was investigated for histone H4 acetylation in PFC samples. After chromatin immunoprecipitation with anti‐acetyl histone H4 antibody, we found an increase in histone acetylation by two different primer pairs which amplified the ?1365 to ?1202 (P < 0.005) and ?170 to +12 (P < 0.05) upstream regions of the DRD1 promoter. Our results suggest that intermittent subcutaneous nicotine administration increases the expression of DRD1 mRNA in the PFC of rats, and this increase may be due to changes in histone H4 acetylation of the 2kb promoter of the DRD1 gene. Synapse 67:545–552, 2013. © 2013 Wiley Periodicals, Inc.     

Increased serum renalase in hemodialysis patients: is it related to left ventricular hypertrophy?

Introduction: Left ventricular hypertrophy (LVH) is one of the most common cardiac abnormalities in patients with end stage renal disease (ESRD). Hypertension, diabetes, increased body mass index, gender, age, anemia, and hyperparathyroidism have been described as risk factors for LVH in patients on dialysis. However, there may be other risk factors which have not been described yet. Recent studies show that renalase is associated with cardiovascular events. The aim of this study was to reveal the relation between renalase, LVH in patients under hemodialysis (HD) treatment.

Methods: The study included 50?HD patients and 35 healthy controls. Serum renalase levels and left ventricle mass index (LVMI) were measured in all participants and the relation between these variables was examined.

Findings: LVMI was positively correlated with dialysis vintage and C-reactive protein (CRP) (r?=?0.387, p?=?0.005 and r?=?0.597, p?r?=??0.324, p?=?0.022 and r?=??0.499, p?r?=?0.263, p?=?0.065). Serum renalase levels were significantly higher in HD patients (212?±?127?ng/mL) compared to controls (116?±?67?ng/mL) (p?r?=?0.677, p?r?=?0.625, p?Discussion: In our study, LVMI was correlated with dialysis vintage, residual diuresis, CRP, and hemoglobin. LVMI tends to correlate with renalase and this correlation may be significant in studies with more patient numbers. The main parameters affecting renalase levels are dialysis vintage and serum creatinine.