Association between albuminuria and thyroid function in patients with chronic kidney disease

Impaired sensitivity to thyroid hormones is associated with albuminuria in the euthyroid population: results from NHANES

PURPOSE

The relationship between thyroid hormone sensitivity and albuminuria remains unclear. We aimed to investigate the association between thyroid hormone sensitivity and the risk of albuminuria in a euthyroid population.

METHODS

This cross-sectional study included 7634 euthyroid adults collected from the National Health and Nutrition Examination Survey (NHANES) between 2007 and 2012. Central sensitivity to thyroid hormones was evaluated using the thyroid-stimulating hormone index (TSHI), the thyrotrophic thyroxine resistance index (TT4RI), and the thyroid feedback quantile-based index (TFQI). Peripheral sensitivity to thyroid hormones was measured using the free triiodothyronine/free thyroxine (FT3/FT4) ratio. Furthermore, the independent relationship between sensitivity to thyroid hormones and albuminuria was assessed.

RESULTS

The proportion of albuminuria increased with a higher interquartile range of TFQI levels (7.31% vs. 7.89% vs. 7.95% vs. 9.89%, P = 0.024). Furthermore, TFQI was found to be independently associated with the risk of albuminuria after adjusting for confounding factors (OR = 1.28, 95% CI 1.01-1.60, P = 0.037). Subgroup analysis revealed a significant relationship between TFQI and albuminuria, especially among individuals over 60.

CONCLUSIONS

In euthyroid subjects, impaired central sensitivity to thyroid hormones is associated with albuminuria. TFQI holds significant potential as an epidemiological tool for quantifying the impact of impaired central sensitivity on the risk of albuminuria.

Analysis of Thyroid Function in ANCA-Associated Vasculitis Patients with Renal Injury

BACKGROUND

Previous studies indicated common thyroid dysfunction in various kidney diseases. This study aimed to investigate the thyroid function in patients with antineutrophil cytoplasmic antibody-associated vasculitis (AAV) with renal injury.

METHODS

Briefly, 174 patients diagnosed as having AAV with renal injury and without previous thyroid disease history were included in the retrospective and prospective study. The clinical parameters were collected and compared between different groups.

RESULTS

Of the patients included, 24 exhibited normal thyroid function, while 150 had thyroid dysfunction, including 55 (36.67%) with hypothyroidism. Those AAV patients with thyroid dysfunction showed different clinical parameters from those with normal thyroid function. The patients were followed up for a median of 68.6 (64.3; 72.8) months. Those with thyroid dysfunction were more prone to progressing to dialysis dependence compared to the group with normal thyroid function. Logistic regression analysis showed advanced age and decreased albumin as independent risk factors for thyroid dysfunction in patients with AAV. Survival analysis and multivariate Cox regression analysis showed that thyroid dysfunction was a risk factor for AAV patients with renal injury to progress to the endpoint of dialysis dependence.

CONCLUSION

Thyroid dysfunction, predominantly hypothyroidism, was commonly complicated in AAV patients with renal injury. AAV patients with thyroid dysfunction were presented with different clinical parameters and more prone to progressing to dialysis dependence compared to those with normal thyroid function.

Urinary excretion of thyroid hormone in CKD patients: a proof-of-concept of nephrogenic hypothyroidism

PURPOSE

Patients with chronic kidney disease (CKD) complicated by hypothyroidism exhibit a higher prevalence of urine protein than that in the general population. This study was aimed at investigating thyroid hormones and thyroid hormone-binding proteins excreted in urine to elucidate the urine protein-associated underlying mechanisms of hypothyroidism.

METHODS

Between November 2016 and August 2018, thyroid function (serum free T3 [sFT3], free T4 [sFT4], and thyroid-stimulating hormone [sTSH]), kidney function (estimated glomerular filtration rate [eGFR]), thyroid antibodies and albumin (Alb) were evaluated in 99 Japanese CKD patients with proteinuria at our outpatient clinic. A urine examination was also performed to assess the following parameters: total T3, total T4, TSH, Alb, preAlb, thyroid-binding globulin, and protein.

RESULTS

The median patient age at study recruitment was 60 years; 50 patients (50.5%) were male. The median eGFR and Alb level were 20.3 ml/min/1.73 m2 and 3.8 g/dL, respectively. 21 patients (21.2%) were diagnosed with nephrotic syndrome (NS). The median sFT3, sFT4, and sTSH levels were within normal limits. Approximately 70% of the patients had thyroid dysfunction and 51.5% had overt or subclinical hypothyroidism without predominantly antibody positive. Regarding NS and non-NS patients, age and Alb were significantly different between these groups, while sex and eGFR were not significant, but the urinary T4 and TSH levels were higher in the NS group; thus, more severe hypothyroid.

CONCLUSION

We found a significant association between hypothyroidism and NS regardless of sex and antibodies. Urinary loss of thyroid hormones must be a factor influencing hypothyroidism independent of autoimmunity.

Measurement of free fraction, total concentration and protein binding for testosterone, triiodothyronine and thyroxine

Aims: Measuring the total and free concentrations of hormones is useful, but the technology to do this simultaneously is lacking. Methods: A new method offers the ability to measure these parameters concurrently for testosterone, thyroxine and triiodothyronine. Results: The free concentrations showed significant correlations with patients' vital statistics. Overall, 67% of correlations for total concentration showed that the new and classical methods had equal accuracy, or that comprehensive ultrafiltration was more accurate. The protein binding term was found to correlate significantly with the patients' luteinizing hormone, prostate-specific antigen and height. Conclusion: Comprehensive ultrafiltration for measuring the total concentration, free concentration and protein binding term uses less sample and is much faster than measuring these parameters with three separate methods.

High Thyroid-Stimulating Hormone and Low Free Triiodothyronine Levels Are Associated with Chronic Kidney Disease in Three Population-Based Studies from Germany

High serum thyroid-stimulating hormone (TSH) levels have previously been associated with a low estimated glomerular filtration rate (eGFR), but studies associating thyroid hormone levels with albuminuria revealed inconsistent results. We used cross-sectional data from 7933 individuals aged 20 to 93 years of the Berlin Aging Study II and the Study of Health in Pomerania to associate serum TSH, fT3, and fT4 levels with eGFR and albuminuria. In multivariable analyses adjusted for confounding, we found inverse non-linear associations of serum TSH levels with eGFR, while serum fT3 levels showed a positive association with eGFR. High as well as low serum fT4 levels were associated with a lower eGFR. Age but not sex modified the association between thyroid hormone levels and eGFR. The inverse associations between serum TSH levels and eGFR were strongest in the youngest age groups, while the positive associations between serum fT3 levels and eGFR were strongest in older individuals. No significant associations between thyroid hormone levels and albuminuria were found. Our results indicate that hypothyroidism might be associated with a reduced kidney function. Thyroid function might be more tightly related to the eGFR than to albuminuria in the general population.

Advance in the Correlation between Diabetic Nephropathy and Abnormal Serum Thyroid Hormone Levels in Patients

This study was developed to explore the correlation between diabetic nephropathy (DN) and abnormal serum thyroid hormone (TH) levels in patients, which can provide a reference for disease prevention and control in patients with DN. DN is the most serious complication of diabetes. The mortality rate of diabetic patients with DN is approximately 30 times higher than that of diabetic patients without DN. DN leads to high blood sugar, which causes vascular dysfunction in patients, causes cardiovascular disease, aggravates the disease and disease complexity, and thus increases the mortality of patients. DN patients often have oxidative stress and even fibrosis in severe cases. TH has a potential renal protective effect and can also regulate glucose metabolism and improve abnormal glucose tolerance and insulin resistance. Abnormal serum TH levels increase the risk of DN. Normal thyroid function plays an important role in regulating the physiological functions of the human body. Hormonal disorders promote the development of diabetes mellitus (DM) into DN. The pathogenesis, clinical manifestations, detection, and treatment methods of DN were reviewed in this study. The research progress of the influence of TH on DN was analyzed. This study is conducive to clinical research on DN and provides a reference.

It’s Not Lupus This Time! A Case of Worsening Hypothyroidism in a Patient With Nephrotic Syndrome

Nephrotic syndrome can result in worsening of existing hypothyroidism in patients requiring thyroid hormone supplementation. The urinary loss of thyroxine-binding globulin, as well as increased gut edema, likely lead to reduced absorption and retention of exogenous thyroid hormone. Here, we present a case of a patient with Hashimoto’s thyroiditis, previously well-controlled on levothyroxine, who developed symptomatic hypothyroidism as a result of newly diagnosed nephrotic syndrome, whose symptoms improved with transition to an alternative formulation of levothyroxine and treatment of her underlying nephrotic syndrome. It is important to consider nephrotic syndrome as a cause of worsening hypothyroidism in a patient on a fixed dose of levothyroxine given the potential morbidity associated with a missed diagnosis and often need for escalation of dosage. There is no standardized therapy for hypothyroidism exacerbated by nephrotic syndrome, but liquid or gel formulations of levothyroxine may be more effective in patients with absorption problems.

The Correlation between Thyroid Hormone Levels and the Kidney Disease Progression Risk in Patients with Type 2 Diabetes

OBJECTIVE

We investigated the relationship between thyroid hormones and the risk of diabetic kidney disease (DKD) progression.

METHODS

A total of 452 patients with type 2 diabetes were included, and a cross-sectional analysis was performed. Urine albumin/creatinine ratio (ACR) and estimated glomerular filtration rate (eGFR) were used to diagnose persistent albuminuria and stage chronic kidney disease, respectively. The Kidney Disease: Improving Global Outcomes (KDIGO) clinical practice guideline was used to describe the risk of DKD progression (low, moderate, and high or very high risks).

RESULTS

The DKD group had higher levels of thyroid-stimulating hormone (TSH) and lower levels of free triiodothyronine (FT3) and free thyroxine (FT4) than the non-DKD group. The prevalence of thyroid dysfunction in the DKD group was significantly higher than in the non-DKD group, especially the prevalence of subclinical hypothyroidism. FT3 levels decreased gradually with the deterioration of DKD. TSH levels increased with an increasing KDIGO category. FT3 and FT4 levels were negatively correlated with serum creatinine levels and ACR, and positively correlated with eGFR. Contrastingly, TSH was positively correlated with ACR, and negatively correlated with eGFR. After adjustment, an increase in FT3 levels significantly reduced the risk of DKD [odds ratio, OR (95% confidence interval, CI)=0.58 (0.42-0.79)] and DKD progression [ORs (95% CIs)=0.65 (0.45-0.93) for the moderate risk group and 0.50 (0.33-0.74) for the high or very high-risk group, using the low-risk group as a reference]. FT3 levels below 4.30 pmol/L in men and 3.99 pmol/L in women were the cut-off points for an increased risk of DKD progression.

CONCLUSION

Low FT3 level is an independent risk factor for DKD and DKD progression. FT3 ≤4.30 pmol/L in men and ≤3.99 pmol/L in women will greatly increase the risk of kidney disease progression in patients with type 2 diabetes.