Effect of adjuvant androgen deprivation on thyroid function tests in prostate cancer patients

Androgen deprivation therapy for prostate cancer and the risk of thyroid diseases

BACKGROUND

Androgen deprivation therapy (ADT) is the major treatment for metastatic prostate cancer (PCa), but few studies have investigated the effects of ADT on thyroid diseases.

METHODS

This population-based, nationwide cohort study utilized the Taiwan National Health Insurance Research Database (NHIRD) with 17,192 PCa patients between 1997 and 2013. We used the Cox proportional hazards models and propensity score-matched analysis to analyze the association between ADT and the development of thyroid diseases.

RESULTS

A total of 17,192 newly diagnosed men with PCa were selected from the NHIRD. There were 6200 ADT users and 6200 non-ADT users after 1:1 propensity score matching. There was a significantly decreased risk of thyroid diseases among ADT users compared with non-ADT users (adjusted hazard ratio (aHR): 0.79, 95% confidence interval (CI): 0.65-0.95, p < 0.001). Further analysis showed a significantly decreased risk of thyroid diseases with increasing ADT duration (p < 0.001).

CONCLUSIONS

The result showed that ADT use in men with PCa was associated with a decreased risk of thyroid disease development.

Myxedema Coma Following the Administration of Gonadotropin-releasing Hormone Agonist Complicated by Acute Pancreatitis

Gonadotropin-releasing hormone (GnRH) agonists have been used for the treatment of various diseases. Although autoimmune thyroid disease has been reported as a rare complication of these agents, the symptoms are almost always transient and non-life-threatening. We herein report a rare case of an 83-year-old man receiving GnRH agonist treatment for prostate cancer who developed myxedema coma complicated by acute pancreatitis. This is the first report of myxedema coma potentially associated with a GnRH agonist. The follow-up of the thyroid function is necessary for patients undergoing treatment with GnRH agonists, especially those known to have or to be susceptible to autoimmune thyroid disease.

Hypothalamic-Pituitary-Thyroid Axis Set Point Alterations Are Associated With Body Composition in Androgen-Deprived Men

Objective:

Androgen deprivation therapy (ADT) given to men with prostate cancer is associated with metabolically adverse changes in body composition leading to insulin resistance, but the underlying mechanisms are not fully understood. We investigated prospectively whether androgen deprivation or its consequences may be associated with alterations in thyroid function in men.

Design:

We performed a prespecified secondary analysis of a prospective case control study.

Methods:

We prospectively followed men with nonmetastatic prostate cancer newly commencing ADT (n = 34) and age-matched controls (n = 29) for 12 months. We assessed secondary outcomes on thyrotropin (TSH) and thyroid hormones using a linear mixed model to determine mean adjusted differences (MADs) between groups.

Results:

After a 12-month follow-up period, TSH increased in cases compared with control subjects [MAD, 0.69 mIU/L; 95% confidence interval (CI), 0.58–0.82; P < 0.001]. This was accompanied by a rise in FT4 (MAD, 2.2 pmol/L; 95% CI, 1.1–3.2; P < 0.001), reduced FT3-FT4 conversion (MAD, −0.07; 95% CI, −0.10 to −0.4; P < 0.001), and stable FT3. TSH change correlated significantly with changes in weight, body mass index, and fat mass in cases but not with waist circumference, lean mass, visceral fat, insulin resistance, testosterone, sex hormone binding globulin, and estradiol. The rise in TSH after 12 months was strongly associated with changes in leptin.

Conclusions:

A profound rise in TSH in the absence of peripheral hypothyroidism under ADT suggests set point adaptations of the hypothalamic-pituitary-thyroid axis. This appears to be mediated by body composition changes and by the fat-associated hormone leptin rather than by androgen deficiency. Further studies are required to determine the causality and biological implications of these findings.

Long-term side effects of androgen deprivation therapy in men with non-metastatic prostate cancer: A systematic literature review

Increasing numbers of men with non-metastatic disease are receiving androgen deprivation therapy (ADT) for a variety of indications, some of which are supported by evidence from randomized trials. Balanced against possible survival benefits and better disease control are data that ADT adversely affects quality of life, particularly in the areas of sexual function, physical function, and energy. There is some evidence of worsening upper extremity physical strength but no clear evidence of decline in daily function with ADT. The impact of ADT on cognitive function is not clear at this time. ADT is associated with declines in bone mineral density within 6-12 months of commencing treatment, with increased fracture rates within 5 years of treatment. ADT use is also associated with a 10-15g/L decline in hemoglobin, although the clinical significance of this drop appears to be limited for most patients. It is reasonable for physicians who are about to start men on ADT to obtain a baseline bone mineral density, to counsel them about the impact on sexual function and possible treatments for sexual dysfunction, and to encourage regular exercise. Further insight into adverse effects of ADT and strategies to minimize these adverse effects await data from ongoing studies.

Effect of androgen deprivation therapy in the thyroid function test of patients with prostate cancer

We have assessed the effect of androgen deprivation therapy (ADT) in the thyroid function test in prostate cancer patients. Serum levels of tri-iodothyronine (T3), thyroxine (T4), free thyroxine (FT4) and thyroid-stimulating hormone (TSH) were determined in a cross-sectional study that included 279 patients diagnosed with prostate cancer. A subset of 96 patients free of prostate-specific antigen relapse after radical prostatectomy became a control group and 183 patients under continuous ADT formed the study group. Sixty-four patients out of the study group were treated with luteinizing hormone-releasing hormone (LHRH) agonist and 119 with LHRH agonist plus bicalutamide. The average time of ADT was 42.5 months (3-218). Results were as follows. Mean T3 level was 122.7 ng/dl (72.6-213.0) in the control group and 123.8 ng/dl (64.4-228.2) in patients under ADT, p=0.472. Mean T4 level was 7.66 (1.81-4.30) and 7.66 microg/dl (3.60-13.30), respectively, p=0.884. Mean TSH level was 1.58 (0.44-11.70) and 1.81 mU/dl (0.15-6.58), respectively, p=0.007. Mean FT4 level was 1.24 (0.80-1.90) and 1.18 ng/dl (0.80-1.90), respectively, p=0.018. No statistically significant differences between the T3, T4, TSH and FT4 serum levels were detected according to the modality of ADT. The serum level of TSH was higher than 5 mU/l in six patients (2.1%); however, all cases had a normal FT4 serum level. This mild hypothyroidism was detected in two of the 96 patients of the control group (2.1%) and in four of the 183 under ADT (2.2%). Our data show that ADT seems to alter the thyroid function test. A statistically significant increase in TSH serum level and a decrease in FT4 serum level were detected in patients under ADT. However, only a mild hypothyroidism was detected in about 2% of the patients with prostate cancer, independently of ADT.