Subclinical thyroid dysfunction and cognitive decline in old age

<p>Background: Subclinical thyroid dysfunction has been implicated as a risk factor for cognitive decline in old age, but results are inconsistent. We investigated the association between subclinical thyroid dysfunction and cognitive decline in the PROspective Study of Pravastatin in the Elderly at Risk (PROSPER).</p> <p>Methods: Prospective longitudinal study of men and women aged 70–82 years with pre-existing vascular disease or more than one risk factor to develop this condition (N = 5,154). Participants taking antithyroid medications, thyroid hormone supplementation and/or amiodarone were excluded. Thyroid function was measured at baseline: subclinical hyper- and hypothyroidism were defined as thyroid stimulating hormones (TSH) <0.45 mU/L or >4.50 mU/L respectively, with normal levels of free thyroxine (FT4). Cognitive performance was tested at baseline and at four subsequent time points during a mean follow-up of 3 years, using five neuropsychological performance tests.</p> <p>Results: Subclinical hyperthyroidism and hypothyroidism were found in 65 and 161 participants, respectively. We found no consistent association of subclinical hyper- or hypothyroidism with altered cognitive performance compared to euthyroid participants on the individual cognitive tests. Similarly, there was no association with rate of cognitive decline during follow-up.</p> <p>Conclusion: We found no consistent evidence that subclinical hyper- or hypothyroidism contribute to cognitive impairment or decline in old age. Although our data are not in support of treatment of subclinical thyroid dysfunction to prevent cognitive dysfunction in later life, only large randomized controlled trials can provide definitive evidence.</p&gt

Subclinical thyroid dysfunction and cognitive decline in old age

<p>Background: Subclinical thyroid dysfunction has been implicated as a risk factor for cognitive decline in old age, but results are inconsistent. We investigated the association between subclinical thyroid dysfunction and cognitive decline in the PROspective Study of Pravastatin in the Elderly at Risk (PROSPER).</p> <p>Methods: Prospective longitudinal study of men and women aged 70–82 years with pre-existing vascular disease or more than one risk factor to develop this condition (N = 5,154). Participants taking antithyroid medications, thyroid hormone supplementation and/or amiodarone were excluded. Thyroid function was measured at baseline: subclinical hyper- and hypothyroidism were defined as thyroid stimulating hormones (TSH) <0.45 mU/L or >4.50 mU/L respectively, with normal levels of free thyroxine (FT4). Cognitive performance was tested at baseline and at four subsequent time points during a mean follow-up of 3 years, using five neuropsychological performance tests.</p> <p>Results: Subclinical hyperthyroidism and hypothyroidism were found in 65 and 161 participants, respectively. We found no consistent association of subclinical hyper- or hypothyroidism with altered cognitive performance compared to euthyroid participants on the individual cognitive tests. Similarly, there was no association with rate of cognitive decline during follow-up.</p> <p>Conclusion: We found no consistent evidence that subclinical hyper- or hypothyroidism contribute to cognitive impairment or decline in old age. Although our data are not in support of treatment of subclinical thyroid dysfunction to prevent cognitive dysfunction in later life, only large randomized controlled trials can provide definitive evidence.</p&gt

Multi-Omics Analysis Reveals MicroRNAs Associated With Cardiometabolic Traits

MicroRNAs (miRNAs) are non-coding RNA molecules that regulate gene expression. Extensive research has explored the role of miRNAs in the risk for type 2 diabetes (T2D) and

ApoE Plasma Levels and Risk of Cardiovascular Mortality in Old Age

BACKGROUND: The ɛ2, ɛ3, and ɛ4 alleles of the apolipoprotein E gene (APOE) encode three isoforms, apoE2, E3, and E4, respectively. The apoE isoforms circulate in different plasma concentrations, but plasma concentrations of the same isoform also differ between individuals. Whereas the isoforms have been associated with cardiovascular disease, the relation between plasma apoE levels and cardiovascular disease is unknown. METHODS AND FINDINGS: We assessed APOE genotypes, plasma levels of apoE, cardiovascular risk factors, and mortality in a population-based sample of 546 individuals aged 85 y who participated in the Leiden 85-plus Study and were prospectively followed for specific causes of death for 5 y. Participants in the highest tertile of apoE levels suffered a twofold-increased risk of cardiovascular mortality (hazard ratio compared to lowest tertile, 2.08; 95% confidence interval [CI], 1.30 to 3.33). Among the 324 participants with the ɛ3ɛ3 genotype, the hazard from cardiovascular disease was threefold increased (highest versus lowest tertile 3.01; 95% CI 1.60 to 5.66), with similar estimates for men and women. Other causes of death were not increased significantly. Plasma levels of apoE in ɛ3ɛ3 participants were positively correlated with total cholesterol ( p < 0.001), low-density lipoprotein cholesterol ( p < 0.001) and triglycerides ( p < 0.001) and negatively with high-density lipoprotein cholesterol levels ( p = 0.010). Adjustment for plasma lipids did not change the hazard ratios, whereas interaction was absent. The risk associated with high levels of apoE, however, was strongest in participants from the lowest tertile of C-reactive protein (CRP) levels and absent in those from the highest tertile ( p (interaction) < 0.001). Among participants from the lowest tertile of CRP levels, those with a high apoE levels had a significantly steeper increase in CRP than those with low apoE levels ( p = 0.020). Similar cardiovascular mortality risks as in ɛ3ɛ3 participants were found in ɛ2 and ɛ4 carriers. CONCLUSIONS: In old age, high plasma apoE levels precede an increase of circulating CRP and strongly associates with cardiovascular mortality, independent of APOE genotype and plasma lipids

Predominance of the adrenomyeloneuropathy phenotype of X-linked adrenoleukodystrophy in The Netherlands: a survey of 30 kindreds

X-linked adrenoleukodystrophy (X-ALD) is an inherited disorder of peroxisomal beta-oxidation associated with accumulation of saturated very long-chain fatty acids, which results in central and peripheral demyelination and in impaired function of adrenal cortex and testes. The phenotypic expression is highly variable, childhood cerebral ALD (CCALD) and adrenomyeloneuropathy (AMN) being the main variants. We explored the 30 Dutch kindreds well known to the Dutch X-ALD/AMN Study Group and phenotyped 77 male patients: 35 (46%) had AMN and 24 (31%) CCALD or adolescent cerebral ALD (AdolCALD). These percentages differ significantly from previous reports, in which 25 to 28% of the patients developed AMN and 53 to 57% CCALD or AdolCALD. Our findings indicate that--at least in the Netherlands--AMN may be the most frequent phenotype of X-AL

Circadian variations in serum levels and the renal toxicity of aminoglycosides in patients

Animals show a faster clearance and a lower incidence of nephrotoxicity and ototoxicity when aminoglycosides are administered during the activity period. Human data on a circadian rhythm in pharmacokinetics are conflicting, and there are no data on a circadian rhythm in toxicity. When aminoglycosides are administered once daily, as is often done, a circadian rhythm in pharmacokinetics or toxicity could have clinical implications. In a prospective study we investigated the influence of drug administration time on serum drug levels and the incidence of nephrotoxicity in 221 patients with serious infections treated with gentamicin or tobramycin once daily. We did not find statistically significant differences in trough or peak levels for the three time periods (midnight to 7:30 AM, 8 AM to 3:30 PM, and 4 to 11:30 PM). Nephrotoxicity occurred significantly more frequently when the aminoglycosides were administered during the rest period (midnight to 7:30 AM; p = 0.004). In addition to the coadministration of high-dose furosemide or other nephrotoxic antibiotics and the duration of treatment, the time of administration was still an independent risk factor in a multivariate analysi

Validation and nephrotoxicity of a simplified once-daily aminoglycoside dosing schedule and guidelines for monitoring therapy.

There is no established dosing schedule for once-daily aminoglycoside dosing regimens, and accepted guidelines for monitoring therapy are lacking. We derived a simplified schedule from the Hull and Sarubbi (J. H. Hull and F. A. Sarubbi, Ann. Intern. Med. 85:183-189, 1976) nomogram, for which efficacy and safety in a once-daily dosing regimen were previously demonstrated, and prospectively followed serum aminoglycoside levels in patients. The standard treatment was gentamicin or tobramycin at 4 mg/kg of body weight given intravenously once daily. When the renal function was decreased, the daily dose was reduced, as follows: for an estimated creatinine clearance of between 50 and 80 ml/min, the daily dose was 3.25 mg/kg, for an estimated creatinine clearance of between 30 and 50 ml/min, the daily dose was 2.5 mg/kg, and for an estimated creatinine clearance of below 30 ml/min, the daily dose was 2 mg/kg. A total of 221 patients were studied (184 received gentamicin and 37 received tobramycin). First trough levels above 2 mg/liter were recorded in 11% of the patients, and they all had a baseline creatinine clearance below 50 ml/min, or a substantial decrease in clearance between enrollment and the day that the trough level was obtained. A peak level below 6 mg/liter was recorded in 6% of the patients, and half of them received the lowest daily dose. Twenty-five of the 179 evaluable patients (14%; 95% confidence interval, 9 to 19%) fulfilled the criteria for nephrotoxicity. In a multiple regression analysis, the duration of treatment and the use of other nephrotoxic antibiotics or high-dose furosemide, but not trough levels, were significant risk factors. Since the meaning of low peak levels is unclear and since most studies with multiple daily regimens confirm the lack of an association between trough levels and toxicity, we believe that monitoring of serum drug levels can be restricted to monitoring of trough levels in patients with a creatinine clearance below 50 ml/min or with a deteriorating renal function

Risk factors for hepatotoxicity in HIV-1-infected patients receiving ritonavir and saquinavir with or without stavudine

Liver enzyme elevation (LEE) is commonly observed after combination antiretroviral therapy (ARVT) for HIV infection is begun. Potential risk factors for LEE after treatment with ritonavir and saquinavir with or without stavudine were investigated in 208 HIV-infected patients, by use of the Cox proportional hazard model. Eighteen patients (9%) developed LEE during the 48-week follow-up. Multivariate analysis, adjusted for baseline levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), showed that hepatitis B surface antigen (HBsAg) positivity (relative risk [RR], 8.8; 95% confidence interval [CI], 3.3-23.1) and the use of stavudine (RR, 4.9; 95% CI, 1.5-16.0) were the only significant risk factors for developing LEE. After LEE occurred, ALT and AST concentrations decreased by >50% in 13 of 14 patients who continued ARVT during LEE. In this study, it appeared safe to continue ARVT during LEE; however, more data from larger studies are required to confirm this finding

Predictive value for survival of soluble tumor necrosis factor receptors p55 and p75 during zidovudine-containing treatment in symptomatic human immunodeficiency virus type 1 infection

Previous studies of asymptomatic human immunodeficiency virus (HIV) infection have shown that serum levels of soluble tumor necrosis factor receptors (sTNFR) are good predictors of disease progression and clinical outcome during zidovudine (ZDV) therapy. The present study of symptomatic HIV infection was designed to evaluate whether sTNFR p55 and p75 at weeks 0 (pretreatment) and 24 and 48 are predictors of death or = 150 x 10(6)/L were included. At baseline, in the nonsurvivor group, mean age (42.1 vs. 34.4 years, p = 0.002) and neopterin (24.7 vs. 18.0 nmol/L, p = 0.02) were higher, whereas mean CD4+ T-cell counts (202 vs. 295 x 10(6)/L, p = 0.02) were lower than in the survivors. All analyses were adjusted for age. For the pretreatment marker values, a significant relative risk (RR) for death was noted only in the univariate analysis for sTNFR-p55 > 1.7 ng/ml [RR 3.1; 95% confidence interval (CI) 1.1-8.8; p = 0.04]. During therapy, CD4+ counts 20 nmol/ml at week 48 were independent predictors of survival in the uni- and multivariate analysis. Marker values relative to baseline were not predictive. sTNFR-p55 and p75 were of little use as surrogate markers for clinical efficacy during ZDV-containing drug regimens in symptomatic HIV-infected patients with CD4+ counts 150 x 10(6)/