Increased Mortality Risk in Patients With Primary and Secondary Adrenal Insufficiency

The Journal of Clinical Endocrinology & Metabolism, dgab096, https://doi.org/10.1210/clinem/dgab096

Abstract

Context

Mortality data in patients with adrenal insufficiency are inconsistent, possibly due to temporal and geographical differences between patients and their reference populations.

Objective

To compare mortality risk and causes of death in adrenal insufficiency with an individually-matched reference population.

Design

Retrospective cohort study.

Setting

UK general practitioner database (CPRD).

Participants

6821 patients with adrenal insufficiency (primary, 2052; secondary, 3948) and 67564 individually-matched controls (primary, 20366; secondary, 39134).

Main outcome measures

All-cause and cause-specific mortality; hospital admission from adrenal crisis.

Results

With follow-up of 40799 and 406899 person-years for patients and controls respectively, the hazard ratio (HR; [95%CI]) for all-cause mortality was 1.68 [1.58 – 1.77]. HRs were greater in primary (1.83 [1.66 – 2.02]) than in secondary (1.52 [1.40 – 1.64]) disease; (HR; primary versus secondary disease, 1.16 [1.03 – 1.30]). The leading cause of death was cardiovascular disease (HR 1.54 [1.32-1.80]), along with malignant neoplasms and respiratory disease. Deaths from infection were also relatively high (HR 4.00 [2.15 – 7.46]). Adrenal crisis contributed to 10% of all deaths. In the first two years following diagnosis, the patients’ mortality rate and hospitalisation from adrenal crisis were higher than in later years.

Conclusion

Mortality was increased in adrenal insufficiency, especially primary, even with individual matching and was observed early in the disease course. Cardiovascular disease was the major cause but mortality from infection was also high. Adrenal crisis was a common contributor. Early education for prompt treatment of infections and avoidance of adrenal crisis hold potential to reduce mortality.

PDF available at https://academic.oup.com/jcem/advance-article-abstract/doi/10.1210/clinem/dgab096/6141434?redirectedFrom=fulltext

Successful Cushing’s Surgery Leads to Better Bone Density

Biomarkers in a majority of Cushing’s syndrome patients with surgically induced disease remission showed a high rate of bone turnover and greater bone mineral density one and two years later, a study reports.

Before treatment, these patients were found to have greater bone degradation and poorer bone formation, as can be common to disease-related bone disorders.

Researchers believe their work is the first study of its kind, “and the data obtained will be instrumental for clinicians who care for patients with Cushing’s syndrome.”

The study, “The Effect of Biochemical Remission on Bone Metabolism in Cushing’s Syndrome: A 2‐Year Follow‐Up Study,” was published in the Journal of Bone and Mineral Research.

Two common co-conditions of Cushing’s syndrome are osteopenia, a loss of bone mass, and osteoporosis, in which the body makes too little bone, loses too much bone, or both. Studies suggest up to 80% of people with Cushing’s have evidence of reduced bone mineral density affecting the entire skeleton.

However, few risk factors to predict bone health have been identified so far, and guidelines for osteoporosis management due to Cushing’s are lacking. Uncertainty as to the natural course of osteoporosis once a diagnosis of Cushing’s syndrome has been made is also still evident.

Investigators at the University of Munich, reportedly for a first time, analyzed the natural course of bone mineral density and bone turnover (recycling) in a group of people with endogenous Cushing’s syndrome — which refers to the disease caused by excess cortisol in the bloodstream, often due to a tumor in the adrenal or pituitary glands.

They examined medical records of 89 Cushing syndrome patients with a mean age of 44, of which 74% were women. Of these, 65% had pituitary Cushing’s (Cushing’s disease), 28% had adrenal, and 7% had ectopic Cushing’s, which is caused by tumors outside the adrenal or pituitary glands. A group of 71 age- and sex-matched healthy participants were included as controls.

In all patients, blood samples were collected at the time of diagnosis (baseline) and one and two years after removing one or both adrenal glands or moving tumors affecting the pituitary gland. Blood samples were analyzed for biomarkers related to bone formation and degradation (resorption).

At the study’s beginning, the mean levels of two bone formation markers, osteocalcin and intact PINP, were significantly decreased in patients compared with controls, whereas the bone formation marker alkaline phosphatase was increased.

Both markers for bone degradation — called CTX and TrAcP — were also high, which demonstrated “increased bone resorption and decreased bone formation in [Cushing’s syndrome],” the team wrote.

While bone markers were similar in participants with a reduced bone mass relative to those with a normal bone mass, bone mineral density was lower overall. Bone mineral density was significantly lower in the neck and spine compared with the femur (thigh bone). Normal bone mineral density was reported in 28 (32%) patients, while 46 (52%) had osteopenia, and the remaining 15 (17%) lived with osteoporosis.

A history of low-trauma bone fractures due to osteoporosis occurred in 17 (19%) patients, taking place shortly before diagnosis in more than half of these (58%) people, and more than two years before a Cushing’s diagnosis in the remaining group (42%).

Compared to patients without fractures, those with fractures had a significantly lower T‐score, a bone density measure that represents how close a person is to average peak bone density. While Cushing’s subtype, age, or body mass index (BMI, body fat based on height) did not differ between groups, men had a significantly higher risk of fractures than women (35% of men vs. 14% of women).

Both disease severity and duration did not contribute to fractures rates, but urinary free cortisol (a circulating cortisol measure) was significantly higher in patients with a low T‐score.

At the one year after tumor removal, which led to Cushing’s remission based on blood tests, a significant increase in bone formation markers was reported. These biomarkers decreased slightly at two years post-surgery, but remained elevated.

At the beginning of the study, bone resorption markers were mildly increased, which rose further one year after surgery before returning almost to normal levels by two years. In parallel, bone density measures conducted in 40 patients showed a matching increase in T-score, particularly in the spine.

After two years, bone mineral density improved in 78% of patients, and T-scores improved in 45% of them. No fractures occurred after Cushing’s treatment, and there was no significant correlation between bone turnover markers and better bone mineral density.

“This study analyzes for the first time in a comprehensive way bone turnover markers during the course of [Cushing’s syndrome],” the researchers wrote. “Our data suggest that the phase immediately after remission from [Cushing’s syndrome] is characterized by a high rate of bone turnover, resulting in a spontaneous net increase in bone mineral density in the majority of patients.”

These results “will influence future therapeutic strategies in patients” with Cushing’s syndrome, they added.

 

Steve holds a PhD in Biochemistry from the Faculty of Medicine at the University of Toronto, Canada. He worked as a medical scientist for 18 years, within both industry and academia, where his research focused on the discovery of new medicines to treat inflammatory disorders and infectious diseases. Steve recently stepped away from the lab and into science communications, where he’s helping make medical science information more accessible for everyone.

New study identifies the main genetic causes of autoimmune Addison’s disease

Novel genetic associations could pave the way for early interventions and personalized treatment of an incurable condition.

Scientists from the University of Bergen (Norway) and Karolinska Institutet (Sweden) have discovered the genes involved in autoimmune Addison’s disease, a condition where the body’s immune systems destroys the adrenal cortex leading to a life-threatening hormonal deficiency of cortisol and aldosterone.

Groundbreaking study

The rarity of Addison’s disease has until now made scanning of the whole genome for clues to the disease’s genetic origins difficult, as this method normally requires many thousands of study participants. However, by combining the world’s two largest Addison’s disease registries, Prof. Eystein Husebye and his team at the University of Bergen and collaborators at Karolinska Institutet in Sweden (prof. Kämpe) were able to identify strong genetic signals associated with the disease. Most of them are directly involved in the development and functioning of the human immune system including specific molecular types in the so-called HLA-region (this is what makes matching donors and recipients in organ transplants necessary) and two different types of a gene called AIRE (which stands for AutoImmune REgulator).

AIRE is a key factor in shaping the immune system by removing self-reacting immune cells. Variants of AIRE, such as the ones identified in this study, could compromise this elimination of self-reacting cells, which could lead to an autoimmune attack later in life.

Knowing what predisposes people to develop Addison’s disease opens up the possibilities of determining the molecular repercussions of the predisposing genetic variation (currently ongoing in Prof. Husebye’s lab). The fact that it is now feasible to map the genetic risk profile of an individual also means that personalised treatment aimed at stopping and even reversing the autoimmune adrenal destruction can become a feasible option in the future.

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Contact information:

Professor at the University of Bergen, Eystein Husebye – Eystein.Husebye@uib.no – cell phone +47 99 40 47 88

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.

From https://www.eurekalert.org/pub_releases/2021-02/tuob-nsi021221.php

Thyroid dysfunction highly prevalent in Cushing’s syndrome

Central hypothyroidism is prevalent in about 1 in 2 adults with Cushing’s syndrome, and thyroid function can be restored after curative surgery for most patients, according to study findings.

“Our study findings have confirmed and greatly extended previous smaller studies that suggested a link between hypercortisolism and thyroid dysfunction but were inconclusive due to smaller sample size and short follow-up,” Skand Shekhar, MD, an endocrinologist and clinical investigator in the reproductive physiology and pathophysiology group at the National Institute of Environmental Health Sciences, NIH, told Healio. “Due to our large sample and longer follow-up, we firmly established a significant negative correlation between hypercortisolemia measures — serum and urinary cortisol, serum adrenocorticotropic hormone — and thyroid hormones triiodothyronine, free thyroxine and thyrotropin.”

Shekhar and colleagues conducted a retrospective review of two groups of adults aged 18 to 60 years with Cushing’s syndrome. The first group was evaluated at the NIH Clinical Center from 2005 to 2018 (n = 68; mean age, 43.8 years; 62% white), and the second group was evaluated from 1985 to 1994 (n = 55; mean age, 37.2 years; 89% white). The first cohort was followed for 6 to 12 months to observe the pattern of thyroid hormone changes after surgical cure of adrenocorticotropic hormone-dependent Cushing’s syndrome. The second group underwent diurnal thyroid-stimulating hormone evaluation before treatment and during remission for some cases.

Urinary free cortisol and morning thyroid hormone levels were collected for all participants. In the second group, researchers evaluated diurnal patterns of TSH concentrations with hourly measurements from 3 to 7 p.m. and midnight to 4 p.m. In the first group, adrenocorticotropic hormone and serum cortisol were measured.

In the first cohort, seven participants were receiving levothyroxine for previously diagnosed primary or central hypothyroidism. Of the remaining 61 adults, 32 had untreated central hypothyroidism. Thirteen participants had free T4 at the lower limit of normal, and 19 had subnormal levels. There were 29 adults with subnormal levels of T3 and seven with subnormal TSH.

Before surgery, 36 participants in the first group had central hypothyroidism. Six months after surgery, central hypothyroidism remained for 10 participants. After 12 months, the number of adults with central hypothyroidism dropped to six. Preoperative T3 and TSH levels were negatively associated with morning and midnight cortisol, adrenocorticotropic hormone and urinary free cortisol. In post hoc analysis, a baseline urinary free cortisol of more than 1,000 g per day was adversely associated with baseline and 6-month T3 and free T4 levels.

In the second group, there were 51 participants not on thyroid-modifying drugs who had a thyroid function test 6 or 12 months after surgery. Before surgery, free Tlevels were subnormal in 17 participants, T3 levels were subnormal in 22, and TSH levels were in the lower half of the reference range or below in all but one participant.

After surgery, two participants had below normal free T4, one had subnormal T3, and TSH levels were in the lower half of the reference range or below in 23 of 48 participants. Before surgery, there was no difference in mean TSH between daytime and nighttime. A mean 8 months after surgery, the second group had a normal nocturnal TSH surge from 1.3 mIU/L during the day to 2.17 mIU/L at night (P = .01). The nocturnal TSH increase persisted as long as 3 years in participants who had follow-up evaluations.

“We found a very high prevalence of thyroid hormone deficiency that appears to start at the level of the hypothalamus-pituitary gland and extend to the tissue level,” Shekhar said. “Some of these patients may experience thyroid hormone deficiency symptoms, such as fatigue, depression, cold intolerance, weight gain, etc, as a result of systematic and tissue-level thyroid hormone deficiency. We also noted a strong correlation between hypothyroidism and hypogonadism, which implies that hypothyroid patients are also likely to suffer adverse reproductive effects. Thus, it is imperative to perform thorough thyroid hormone assessment in patients with Cushing’s syndrome, and thyroid hormone supplementation should be considered for these patients unless cure of Cushing’s syndrome is imminent.”

Researchers said providers should routinely screen for hypothyroidism in adults with Cushing’s syndrome. Even after thyroid function is restored, regular follow-up should also be conducted.

Further research is needed to investigate thyroid dysfunction in iatrogenic Cushing’s syndrome and the impact of these findings on euthyroid sick syndrome, Shekhar said.

For more information:

Skand Shekhar, MD, can be reached at skand.shekhar@nih.gov.

From https://www.healio.com/news/endocrinology/20210208/thyroid-dysfunction-highly-prevalent-in-cushings-syndrome

Treatment for Rare Cancer May Help Cushing’s Patients

The cancer medicine bexarotene may hold promise for treating Cushing’s disease, a study suggests.

The study, “Targeting the TR4 nuclear receptor with antagonist bexarotene can suppress the proopiomelanocortin signalling in AtT‐20 cells,” was published in the Journal of Cellular and Molecular Medicine.

Cushing’s disease is caused by a tumor on the pituitary gland, leading this gland to produce too much adrenocorticotropic hormone (ACTH). Excess ACTH causes the adrenal glands to release too much of the stress hormone cortisol; abnormally high cortisol levels are primarily responsible for the symptoms of Cushing’s.

Typically, first-line treatment is surgical removal of the pituitary tumor. But surgery, while effective in the majority of cases, does not help all. Additional treatment with medications or radiation therapy (radiotherapy) works for some, but not others, and these treatments often have substantial side effects.

“Thus, the development of new drugs for CD [Cushing’s disease] treatment is extremely urgent especially for patients who have low tolerance for surgery and radiotherapy,” the researchers wrote.

Recent research has shown that a protein called testicular receptor 4 (TR4) helps to drive ACTH production in pituitary cancers. Thus, blocking the activity of TR4 could be therapeutic in Cushing’s disease.

Researchers conducted computer simulations to screen for compounds that could block TR4. This revealed bexarotene as a potential inhibitor. Further biochemical tests confirmed that bexarotene could bind to, and block the activity of, TR4.

Bexarotene is a type of medication called a retinoid. It is approved to treat cutaneous T-cell lymphoma, a rare cancer that affects the skin, and available under the brand name Targretin.

When pituitary cancer cells in dishes were treated with bexarotene, the cells’ growth was impaired, and apoptosis (a type of programmed cell death) was triggered. Bexarotene treatment also reduced the secretion of ACTH from these cells.

In mice with ACTH-secreting pituitary tumors, bexarotene’s use significantly reduced tumor size, and lowered levels of ACTH and cortisol. Cushing’s-like symptoms also eased; for example, bexarotene treatment reduced the accumulation of fat around the abdomen in these mice.

Additional cellular experiments suggested that bexarotene specifically works on TR4 by changing the location of the protein. Normally, TR4 is present in the nucleus — the cellular compartment that houses DNA — where it helps to control the production of ACTH.

But with bexarotene treatment, TR4 tended to go outside of the nucleus, leading to lower ACTH production. The researchers noted that other mechanisms may also be involved in the observed effects of bexarotene.

“In summary, our work demonstrates that bexarotene is a potential inhibitor for TR4. Importantly, bexarotene may represent a new drug candidate to treat CD,” the researchers concluded.

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