Cushing’s appears to begin its cardiovascular effects during childhood

– Cushing’s disease may begin to exert its harmful cardiovascular effects quite early, a small pediatric study has found.

Children as young as 6 years old with the disorder already may show signs of cardiovascular remodeling, with stiffer aortas and higher aortic pulse-wave velocity than do age-matched controls, Hailey Blain and Maya Lodish, MD, said at the annual meeting of the Endocrine Society.

“The study, which included 10 patients, is small, but we continue to add new patients,” said Dr. Lodish, director of the pediatric endocrinology fellowship program at the Eunice Kennedy Shriver National Institute of Child Health and Human Development. Ten more children are being added to the cohort now, and she and Ms. Blain, a former research fellow at NIH, intend to grow the group and follow patients longitudinally.

Cushing’s disease has long been linked with increased cardiovascular risk in adults, but the study by Dr. Lodish and Ms. Blain is one of the first to examine the link in children. Their findings suggest that early cardiovascular risk factor management should be a routine part of these patients’ care, Dr. Lodish said in an interview.

“It’s very important to make sure that there is recognition of the cardiovascular risk factors that go along with this disease. Elevated levels of cholesterol, hypertension, and other risk factors that are in these individuals should be ameliorated as soon as possible from an early age and, most importantly, physicians should be diagnosing and treating children early, once they are identified as having Cushing’s disease. And, given that we are not sure whether these changes are reversible, we need to make sure these children are followed very closely.”

Indeed, Dr. Lodish has reason to believe that the changes may be long lasting or even permanent.

“We are looking at these children longitudinally and have 3-year data on some patients already. We want to see if they return to normal pulse wave velocity after surgical cure, or whether this is permanent remodeling. There is an implication already that it may be in a subset of individuals,” she said, citing her own 2009 study on hypertension in pediatric Cushing’s patients. “We looked at blood pressure at presentation, after surgical cure, and 1 year later. A significant portion of the kids still had hypertension at 1 year. This leads us to wonder if they will continue to be at risk for cardiovascular morbidity as adults.”

Ms. Blaine, an undergraduate at Bowdoin College, Brunswick, Maine, worked on the study during a summer internship with Dr. Lodish and presented its results in a poster forum during meeting. She examined two indicators of cardiovascular remodeling – aortic pulse wave velocity and aortic distensibility – in 10 patients who were a mean of 13 years old. All of the children came to NIH for diagnosis and treatment of Cushing’s; as part of that, all underwent a cardiac MRI.

The patients had a mean 2.5-year history of Cushing’s disease Their mean midnight cortisol level was 18.8 mcg/dL and mean plasma adrenocorticotropic hormone level, 77.3 pg/mL. Five patients were taking antihypertensive medications. Low- and high-density lipoprotein levels were acceptable in all patients.

The cardiovascular measures were compared to an age-matched historical control group. In this comparison, patients had significantly higher pulse wave velocity compared with controls (mean 4 vs. 3.4 m/s). Pulse wave velocity positively correlated with both midnight plasma cortisol and 24-hour urinary free cortisol collections. In the three patients with long-term follow-up after surgical cure of Cushing’s, the pulse wave velocity did not improve, either at 6 months or 1 year after surgery. This finding echoes those of Dr. Lodish’s 2009 paper, suggesting that once cardiovascular remodeling sets in, the changes may be long lasting.

“The link between Cushing’s and cardiovascular remodeling is related to the other things that go along with the disease,” Dr. Lodish said. “The hypertension, the adiposity, and the high cholesterol all may contribute to arterial rigidity. It’s also thought to be due to an increase in connective tissue. The bioelastic function of the aorta may be affected by having Cushing’s.”

That connection also suggests that certain antihypertensives may be more beneficial to patients with Cushing’s disease, she added. “It might have an implication in what blood pressure drug you use. Angiotensin-converting enzyme inhibitors increase vascular distensibility and inhibit collagen formation and fibrosis. It is a pilot study and needs longitudinal follow up and additional patient accrual, however, finding signs of cardiovascular remodeling in young children with Cushing’s is intriguing and deserves further study.”

Neither Ms. Blain nor Dr. Lodish had any financial disclosures.

Diagnosis and Differential Diagnosis of Cushing’s Syndrome

D. Lynn Loriaux, M.D., Ph.D.

N Engl J Med 2017; 376:1451-1459April 13, 2017DOI: 10.1056/NEJMra1505550

More than a century ago, Harvey Cushing introduced the term “pluriglandular syndrome” to describe a disorder characterized by rapid development of central obesity, arterial hypertension, proximal muscle weakness, diabetes mellitus, oligomenorrhea, hirsutism, thin skin, and ecchymoses.1 Cushing knew that this syndrome was associated with adrenal cancer,2 and he suspected that some cases might have a pituitary component.

On September 6, 1911, he performed a craniotomy on one of his patients (referred to as Case XLV) but found no pituitary tumor.3 In his description of the case, he goes on to say that “we may perchance be on the way toward the recognition of the consequences of hyperadrenalism.”2 With time, it became clear that the disorder could be caused by small basophilic adenomas of the pituitary gland,4 and the pluriglandular syndrome became known as Cushing’s syndrome.

Fuller Albright provided the next conceptual advance in an extraordinary report, published in the first volume of the Laurentian Hormone Conference, “The Effects of Hormones on Osteogenesis in Man”5:

It has been our concept that protoplasm in general, like the protoplasmic matrix of bone, is constantly being anabolized and catabolized at one and the same time; a factor which increases catabolism would lead to very much the same net result as a factor which inhibits anabolism, but there would be some differences; it is my belief that the “S” hormone [cortisol] is anti-anabolic rather than catabolic. . . . The anti-anabolism . . . is contrasted with the increased anabolism due to an excess of the “N” hormone [testosterone] in the adreno-genital syndrome. This anti-anabolism of protoplasm in Cushing’s syndrome accounts for not only the osteoporosis, but the muscular weakness, the thin skin, probably the easy bruisability, and possibly the atrophy of the lymphoid tissues and thymus.

Nonetheless, in the intervening years, the physical examination of patients suspected to have glucocorticoid excess focused on the anabolic changes, essentially to the exclusion of the antianabolic changes. With the rapid increase in the rate of obesity in the general population, Cushing’s syndrome can no longer be reliably separated from the metabolic syndrome of simple obesity on the basis of anabolic signs alone. However, the antianabolic changes in Cushing’s syndrome are very effective in making this distinction. This review focuses on the problems introduced into the diagnosis and differential diagnosis of Cushing’s syndrome by the obesity epidemic and on ways to alter the traditional approach, using the antianabolic changes of excess cortisol to separate patients with Cushing’s syndrome from obese patients with the insulin-resistant metabolic syndrome.

PHYSICAL EXAMINATION

Andreas Vesalius (1514–1564) published his transformational work on human anatomy, De Humani Corporis Fabrica Libri Septem, in 1543. It is the book that corrected many of Galen’s anatomical errors. The book was met with considerable hostility. As an example, Jacobus Sylvius (Jacques Dubois, 1478–1555), the world’s leading anatomist at the time and Vesalius’s former mentor, on being asked his opinion of the work, replied, “Galen is not wrong. It is man that has changed, and not for the better.”6 This was not true then, but it is true now.

Approximately one third of the U.S. population is obese. The worldwide prevalence of the metabolic syndrome among obese persons is conservatively estimated at 10%; that is, approximately 12 million people have the obesity-related metabolic syndrome.7,8 The clinical picture of this syndrome is almost the same as that of Cushing’s syndrome.9,10 The prevalence of undiagnosed Cushing’s syndrome is about 75 cases per 1 million population, or 24,000 affected persons. On the basis of these prevalence estimates, the chance that a person with obesity, hypertension, hirsutism, type 2 diabetes, and dyslipidemia has Cushing’s syndrome is about 1 in 500. In Harvey Cushing’s era, when obesity was rare, making the diagnosis of Cushing’s syndrome was the most certain aspect of the management of this disorder. Today, making the diagnosis is the least certain aspect in the care of patients with Cushing’s syndrome.

The metabolic syndrome caused by glucocorticoid hypersecretion can be differentiated from the obesity-associated metabolic syndrome with the use of a careful assessment of Albright’s antianabolic effects of cortisol. These effects — osteopenia, thin skin, and ecchymoses — are present in patients with Cushing’s syndrome but not in patients with simple obesity.

Patients in whom osteoporosis is diagnosed radiographically are more likely to have Cushing’s syndrome than those who do not have osteoporosis, with a positive likelihood ratio of 11.11-13 Today, a z score of −2 at the lumbar spine supports this criterion. Skinfold thickness is conveniently measured with an electrocardiographic caliper that has the points dulled with a sharpening stone and the screws tightened so that the gap is maintained when the caliper is removed from the skinfold. The skin over the proximal phalanx of the middle finger of the nondominant hand is commonly used for this measurement

 

(Figure 1 FIGURE 1Measurement of Skinfold Thickness.). A thickness of less than 2 mm is considered to be thin skin. Patients who have thin skin are more likely to have Cushing’s syndrome, with a positive likelihood ratio of 116

 

(Figure 2 FIGURE 2 Comparison of Skinfold Thickness in Patients with Cushing’s Syndrome and Those with Other Conditions Related to Insulin Resistance.).13-15 Finally, patients who have three or more ecchymoses that are larger than 1 cm in diameter and not associated with trauma such as venipuncture are more likely to have Cushing’s syndrome than are patients without such findings, with a positive likelihood ratio of 4.13,16

If we know the prevalence of undiagnosed Cushing’s syndrome in the population of persons with the obesity-related metabolic syndrome, we can begin to calculate the probability that a person has Cushing’s syndrome, using the likelihood ratios for the antianabolic features observed on physical examination. Likelihood ratios can be converted into probabilities with the use of Bayes’ theorem. This conversion is markedly facilitated by the Fagan nomogram for this purpose.17

The prevalence of undiagnosed Cushing’s syndrome is not known, but it can be estimated. Two persons per 1 million population die from adrenal cancer every year.18 The current life span for patients with adrenocortical carcinoma, after diagnosis, is between 2 and 4 years.19,20 Allowing 3 years to make the diagnosis, the prevalence of undiagnosed Cushing’s syndrome is 6 cases per million. In most case series of Cushing’s syndrome, an average of 8% of patients have adrenal carcinoma.21 If 6 per million is 8% of the group, the total Cushing’s syndrome group is 75 persons per million, or 24,000 persons. If all 24,000 patients are included in the metabolic syndrome group, comprising 12 million people, the prevalence of Cushing’s syndrome is 0.002, or 0.2%. With a probability of 0.2% and a likelihood ratio of 116 for thin skin, 18 for osteopenia, and 4 for ecchymoses, the probability that a patient with these three findings has Cushing’s syndrome is 95%.

URINARY FREE CORTISOL

The diagnosis of all endocrine diseases requires a clinical presentation that is compatible with the disease, as well as identification of the pathophysiological cause. An assessment for excess glucocorticoid effects can be made by measuring the 24-hour urinary free cortisol level.22 There are two kinds of free cortisol: plasma protein-unbound cortisol and cortisol unconjugated to sulfuric or hyaluronic acid. Protein-unbound cortisol is filtered in the glomerulus and then reabsorbed in the collecting system. About 3% of filtered cortisol ends up in the urine. This free cortisol in the urine is unconjugated. Thus, the urinary free cortisol level is a direct reflection of the free, bioactive cortisol level in plasma. The free cortisol level is quantified in a 24-hour urine sample by averaging the increased secretion of cortisol in the morning and the decreased secretion in the afternoon and at night. Urinary creatinine is also measured to determine whether the collection is complete. Creatinine levels of less than 1.5 g per day for men and less than 1 g per day for women indicate incomplete collection, and the test should be repeated in patients with these levels.

Unconjugated cortisol can be extracted directly from urine with a nonpolar lipid solvent. After extraction, the cortisol is purified by means of high-pressure liquid chromatography and then quantified with a binding assay, usually radioimmunoassay. Free cortisol also can be quantitated directly by means of mass spectroscopy. The urinary free cortisol assay of choice uses high-pressure liquid chromatographic separation followed by mass spectrometric quantitation.23 With the use of this assay, the urinary free cortisol level in healthy adults ranges from 8 to 51 μg per 24 hours (mean [±SD], 23±8). Clinical depression increases urinary free cortisol excretion, and most studies show that the level of urinary free cortisol ranges from 10 to 60 μg per day in patients with typical clinical signs and symptoms of depression. If we use 60 μg per day as the cutoff between normal values (<60 μg per day) and elevated values (≥60 μg per day), urinary free cortisol excretion of 62 μg per day or more has a positive likelihood ratio of 11.24 Thus, in a patient presenting with obesity, hypertension, type 2 diabetes, and hirsutism who has thin skin, osteopenia, ecchymoses, and an elevated urinary free cortisol level, the probability of Cushing’s syndrome is 1 (100%). For such patients, the clinician should move directly to a differential diagnostic evaluation.

DEXAMETHASONE-SUPPRESSION TEST

The dexamethasone-suppression test is commonly used in the diagnosis of Cushing’s syndrome. This test was developed by Grant Liddle in the early 1960s as a differential diagnostic test to separate corticotropin-dependent from corticotropin-independent Cushing’s syndrome. This is now done by measuring the plasma corticotropin level. Unfortunately, dexamethasone suppression has continued to be used as a screening test for Cushing’s syndrome.

The control group for this test comprises patients with obesity and depression in whom cortisol secretion is not suppressed in response to an oral dose of 1 mg of dexamethasone at midnight. Of the current U.S. population of 360 million people, approximately one third (120 million people) are obese. Of those who are obese, 10% (12 million people) have depression. In half these patients (6 million people), the plasma cortisol level will not be suppressed in response to a dexamethasone challenge. On the basis of my estimate of the current prevalence of undiagnosed Cushing’s syndrome (24,000 cases) and the estimate of the at-risk population (6 million persons), the positive predictive value of the dexamethasone-suppression test is only 0.4%. Thus, this test should not influence what the physician does next and should no longer be used for this purpose.

OUTLIERS

For patients with convincing evidence of Cushing’s syndrome on physical examination and an elevated 24-hour urinary free cortisol level, the differential diagnostic process outlined below should be initiated. However, a small group of patients will not meet these criteria.

Some patients have a strongly positive physical examination but low or zero urinary free cortisol excretion. Plasma corticotropin levels are suppressed in these patients. These patients are receiving exogenous glucocorticoids. The glucocorticoid must be identified, and a plan must be made for its discontinuation. Sometimes the glucocorticoid is being given by proxy (e.g., by a parent to a child), and no history of glucocorticoid administration can be found. Nevertheless, the glucocorticoid must be identified and discontinued.

Other patients have few or no clinical signs of Cushing’s syndrome but do have elevated urinary free cortisol excretion. Plasma corticotropin is measurable in these patients. They are usually identified during an evaluation for arterial hypertension. All such patients should undergo inferior petrosal sinus sampling to determine the source of corticotropin secretion. Ectopic sources are almost always neoplastic and are usually in the chest.25 Patients with eutopic secretion usually have the syndrome of generalized glucocorticoid resistance.26

Finally, a few patients have convincing findings on physical examination coupled with a normal urinary free cortisol level. In such cases, the clinician should make sure that urinary free cortisol is being measured with high-performance liquid chromatography and mass spectrometry, that renal function is normal, and that the collections are complete. “Periodic” Cushing’s syndrome must be ruled out by measuring urinary free cortisol frequently over the course of a month.27 If these efforts fail, the patient should be followed for a year, with urinary free cortisol measurements performed frequently. No additional tests should be performed until the situation is sorted out. More tests would be likely to lead to an unnecessary surgical procedure.

DIFFERENTIAL DIAGNOSIS

The differential diagnosis of Cushing’s syndrome is shown in Figure 3

FIGURE 3Differential Diagnosis of Cushing’s Syndrome.. If plasma corticotropin is measurable, the disease process is corticotropin-dependent. If corticotropin is not measurable, the process is corticotropin-independent.

Corticotropin-dependent causes of Cushing’s syndrome are divided into those in which the corticotropin comes from the pituitary (eutopic causes) and those in which the corticotropin comes from elsewhere (ectopic causes). This differentiation is made with the measurement of corticotropin in inferior petrosal sinus plasma and the simultaneous measurement of corticotropin in peripheral (antecubital) plasma immediately after corticotropin-releasing hormone stimulation of pituitary corticotropin secretion. In samples obtained 4, 6, and 15 minutes after stimulation with corticotropin-releasing hormone, eutopic corticotropin secretion is associated with a ratio of the central-plasma corticotropin level to the peripheral-plasma corticotropin level of 3 or more. Ectopic corticotropin secretion is associated with a central-to-peripheral corticotropin ratio of less than 3. The positive predictive value of this test is 1 (Figure 4

FIGURE 4Maximal Ratio of Corticotropin in Inferior Petrosal Sinus Plasma to Corticotropin in Peripheral Plasma in Patients with Cushing’s Syndrome, Ectopic Corticotropin Secretion, or Adrenal Disease.).28

Although some authorities suggest that inferior petrosal sinus sampling can safely be bypassed in patients with corticotropin-dependent Cushing’s syndrome and a well-defined pituitary adenoma, I disagree. The incidence of nonfunctioning pituitary microadenomas is between 15% and 40%.29 This means that up to 40% of patients with ectopic secretion of corticotropin have an incidental pituitary abnormality. If it is assumed that the pituitary abnormality is responsible for corticotropin secretion, 15 to 40% of patients with ectopic secretion of corticotropin will be misdiagnosed and submitted to a transsphenoidal exploration of the sella turcica and pituitary gland. The prevalence of ectopic corticotropin secretion in the population of patients with undiagnosed Cushing’s syndrome is about 10%, accounting for 2400 patients. Up to 40% of these patients, or 960, have an incidental pituitary tumor. The mortality associated with transsphenoidal microadenomectomy is 1%.30 If all 360 to 960 patients undergo this procedure, there will be up to 10 deaths from an operation that can have no benefit. For this reason alone, all patients with corticotropin-dependent Cushing’s syndrome should undergo inferior petrosal sinus sampling to confirm the source of corticotropin secretion before any surgical intervention is contemplated.

Patients with eutopic corticotropin secretion are almost certain to have a corticotropin-secreting pituitary microadenoma. An occasional patient will have alcohol-induced pseudo–Cushing’s syndrome. The slightest suggestion of alcoholism should lead to a 3-week abstinence period before any surgery is considered.31

Patients with ectopic corticotropin secretion are first evaluated with computed tomography (CT) or magnetic resonance imaging (MRI) of the chest. In two thirds of these patients, a tumor will be found.25 If nothing is found in the chest, MRI of the abdominal and pelvic organs is performed. If these additional imaging studies are also negative, there are two options: bilateral adrenalectomy or blockade of cortisol synthesis. If blockade is chosen, the patient should undergo repeat scanning at 6-month intervals.32 If no source is found by the end of the second year, it is unlikely that the source will ever be found, and bilateral adrenalectomy should be performed for definitive treatment (Doppman JL: personal communication).

Corticotropin-independent Cushing’s syndrome is usually caused by an adrenal neoplasm. Benign tumors tend to be small (<5 cm in diameter) and secrete a single hormone, cortisol. The contralateral adrenal gland is suppressed by the cortisol secreted from the tumorous gland. If the value for Hounsfield units is less than 10 and the washout of contrast material is greater than 60% at 15 minutes, the tumor is almost certainly benign.33 Such tumors can be treated successfully with laparoscopic adrenalectomy.

The syndromes of micronodular and macronodular adrenal dysplasia usually affect both adrenal glands. The nodules secrete cortisol. Corticotropin is suppressed, as is the internodular tissue of the adrenal glands. Percutaneous bilateral adrenalectomy, followed by glucocorticoid and mineralocorticoid treatment, is curative.

Adrenal tumors secreting more than one hormone (i.e., cortisol and androgen or estrogen) are almost always malignant. Surgical removal of all detectable disease is indicated, as is a careful search for metastases. If metastases are found, they should be removed. This usually requires an open adrenalectomy. It goes without saying that adrenal tumors, nodules, and metastases should be treated by the most experienced endocrine cancer surgeon available.

If the plasma cortisol level on the morning after a transsphenoidal microadenomectomy is 0, the operation was a success. The patient should be treated with oral hydrocortisone, at a dose of 12 mg per square meter of body-surface area once a day in the morning, and a tetracosactide (Cortrosyn) stimulation test should be performed at 3-month intervals. When the tetracosactide-stimulated plasma cortisol level is higher than 20 μg per deciliter (551 μmol per liter), cortisol administration can be stopped. The same rule applies in the case of a unilateral adrenalectomy. If the adrenalectomy is bilateral, cortisol, at a dose of 12 to 15 mg per square meter per day, and fludrocortisone (Florinef), at a dose of 100 μg per day, should be prescribed as lifelong therapy.

SUMMARY

The obesity epidemic has led to necessary changes in the evaluation and treatment of patients with Cushing’s syndrome. The most dramatic change is the emphasis on the antianabolic alterations in Cushing’s syndrome, which can provide a strong basis for separating patients with Cushing’s syndrome from the more numerous patients with obesity and the metabolic syndrome. More can be done along these lines. Likelihood ratios are known for proximal muscle weakness and can be known for brain atrophy and growth failure in children.

The dexamethasone-suppression test, although still very popular, no longer has a role in the evaluation and treatment of patients with Cushing’s syndrome. Only three biochemical tests are needed: urinary free cortisol, plasma corticotropin, and plasma cortisol measurements. Urinary free cortisol excretion is the test that confirms the clinical diagnosis of Cushing’s syndrome. To be trustworthy, it must be performed in the most stringent way, with the use of high-pressure liquid chromatography followed by mass spectrometric quantitation of cortisol. Measurement of plasma corticotropin is used to separate corticotropin-dependent from corticotropin-independent causes of Cushing’s syndrome and to separate eutopic from ectopic secretion of corticotropin. Inferior petrosal sinus sampling should be performed in all patients with corticotropin-dependent Cushing’s syndrome because of the high prevalence of nonfunctioning incidental pituitary adenomas among such patients. Measurement of plasma cortisol has only one use: determining the success or failure of transsphenoidal microadenomectomy or adrenalectomy. If the plasma cortisol level is not measurable on the morning after the operation (<5 μg per deciliter [138 μmol per liter]), the procedure was a success; if it is measurable, the operation failed. The surgeon must not administer intraoperative or postoperative synthetic glucocorticoids until the plasma cortisol level has been measured.

Successful evaluation of a patient who is suspected of having Cushing’s syndrome requires an endocrinologist who is skilled in physical diagnosis. Also required is a laboratory that measures urinary free cortisol using high-performance liquid chromatography and mass spectrometry and that can measure plasma cortisol and plasma corticotropin by means of radioimmunoassay.

Inferior petrosal sinus sampling is performed by an interventional radiologist. The treatment for all causes of Cushing’s syndrome, other than exogenous glucocorticoids, is surgical, and neurosurgeons, endocrine surgeons, and cancer surgeons are needed. This level of multidisciplinary medical expertise is usually found only at academic medical centers. Thus, most, if not all, patients with Cushing’s syndrome should be referred to such a center for treatment.

Disclosure forms provided by the author are available with the full text of this article at NEJM.org.

No potential conflict of interest relevant to this article was reported.

SOURCE INFORMATION

From the Division of Endocrinology, Diabetes, and Clinical Nutrition, Oregon Health and Science University, Portland.

Address reprint requests to Dr. Loriaux at the Division of Endocrinology, Diabetes, and Clinical Nutrition, Oregon Health and Science University, 3181 SW Sam Jackson Park Rd., L607, Portland, OR 97239-3098, or at .

From http://www.nejm.org/doi/full/10.1056/NEJMra1505550

Severe Trauma May Damage The Brain as Well as the Psyche

NOTE: This is only a portion of the article.  Read the entire post at http://www.nytimes.com/1995/08/01/science/severe-trauma-may-damage-the-brain-as-well-as-the-psyche.html?pagewanted=all

Cortisol is a major means the body uses, with adrenaline, to arouse itself so quickly; its action, for example, triggers an increase in blood pressure and mobilizes energy from fat tissue and the liver.

“The dark side of this picture is the neurological effects,” said Dr. Sapolsky. “It’s necessary for survival, but it can be disastrous if you secrete cortisol for months or years on end. We’ve known it could lead to stress-exacerbated diseases like hypertension or adult onset diabetes. But now we’re finding the hippocampus is also damaged by these secretions.”

Studies in animals show that when glucocorticoids are secreted at high levels for several hours or days, there is a detectable effect on memory, though no neuronal death. But with sustained release from repeated stress, “it eventually kills neurons in the hippocampus,” said Dr. Sapolsky. “This has been shown solidly in rats, with the cell biology well understood.”

A parallel effect has long been known among patients with Cushing’s disease, a hormonal condition in which tumors in the adrenal or pituitary glands or corticosteroid drugs used for a prolonged time cause the adrenal glands to secrete high levels of a hormone called ACTHm and of cortisol. Such patients are prone to a range of diseases “in any organ with stress sensitivity,” including diabetes, hypertension and suppression of the immune system, said Dr. Sapolsky.

Cushing’s patients also have pronounced memory problems, especially for facts like where a car was parked. “The hippocampus is essential for transferring such facts from short-term to long-term memory,” said Dr. Sapolsky.

In 1993, researchers at the University of Michigan reported that magnetic resonance imaging had shown an atrophy and shrinkage of the hippocampus in patients with Cushing’s disease; the higher their levels of cortisol, the more shrinkage.

In an apparent paradox, low levels of cortisol in post-trauma victims were found in a separate research report, also in the July issue of The American Journal of Psychiatry. Dr. Rachel Yehuda, a psychologist at Mount Sinai Medical School in New York City, found the lower levels of cortisol in Holocaust survivors who had been in concentration camps 50 years ago and who still had post-traumatic symptoms.

“There are mixed findings on cortisol levels in trauma victims, with some researchers finding very high levels and others finding very low levels,” said Dr. Sapolsky. “Biologically speaking, there may be different kinds of post-traumatic stress.”

In a series of studies, Dr. Yehuda has found that those post-trauma patients who have low cortisol levels also seem to have “a hypersensitivity in cell receptors for cortisol,” she said. To protect itself, the body seems to reset its cortisol levels at a lower point.

The low cortisol levels “seem paradoxical, but both too much and too little can be bad,” said Dr. Yehuda. “There are different kinds of cells in various regions of the hippocampus that react to cortisol. Some atrophy or die if there is too little cortisol, some if there is too much.”

Dr. Yehuda added, “In a brain scan, there’s no way to know exactly which cells have died.”

To be sure that the shrinkage found in the hippocampus of trauma victims is indeed because of the events they suffered through, researchers are now turning to prospective studies, where before-and-after brain images can be made of people who have not yet undergone trauma, but are at high risk, or who have undergone it so recently that cell death has not had time to occur.

Dr. Charney, for example, is planning to take M.R.I. scans of the brains of emergency workers like police officers and firefighters and hopes to do the same with young inner-city children, who are at very high risk of being traumatized over the course of childhood and adolescence. Dr. Pitman, with Dr. Yehuda, plans a similar study of trauma victims in Israel as they are being treated in emergency rooms.

Dr. Yehuda held out some hope for people who have suffered through traumatic events. “It’s not necessarily the case that if you’ve been traumatized your hippocampus is smaller,” she said. She cited research with rats by Dr. Bruce McEwen, a neuroscientist at Rockefeller University, showing that atrophied dendritic extensions to other cells in the hippocampus grew back when the rats were given drugs that blocked stress hormones.

Dr. Sapolsky cited similar results in patients with Cushing’s disease whose cortisol levels returned to normal after tumors were removed. “If the loss of hippocampal volume in trauma victims is due to the atrophy of dendrites rather than to cell death, then it is potentially reversible, or may be so one day,” he said.

NOTE: This is only a portion of the article.  Read the entire post at http://www.nytimes.com/1995/08/01/science/severe-trauma-may-damage-the-brain-as-well-as-the-psyche.html?pagewanted=all

Screening tool accurately predicts Cushing’s syndrome in most at-risk patients

León-Justel A, et al. J Clin Endocrinol Metab. 2016;doi:10.1210/jc.2016-1673.

A scoring system based on clinical signs and a late-night salivary cortisol test accurately predicted Cushing’s syndrome in at-risk patients, with only one missed case, according to recent findings.

In a prospective, multicenter study, Antonio León-Justel, PhD, of the biochemistry department at the Hospital Universitario Virgen del Rocío in Seville, Spain, and colleagues analyzed data from 353 patients treated in endocrinology units in 13 university hospitals in Spain between 2012 and July 2013. All participants had at least two of five features compatible with Cushing’s syndrome, including obesity, hypertension, poorly controlled diabetes,hirsutism with menstrual disorders and osteoporosis; none of the included patients was referred to clinic with the suspicion of Cushing’s syndrome. All patients underwent late-night salivary cortisol and serum cortisol measurements after a low-dose (1 mg) dexamethasone test; those with discordant results were followed until December 2014 (mean follow-up time, 22.2 months).

Within the cohort, 26 (7.4%) patients were diagnosed with Cushing’s syndrome (20 adrenocorticotropic hormone-dependent; six of adrenal origin). In univariate logistic regression analysis, researchers found that muscular atrophy (OR = 15.2), followed by osteoporosis (OR = 4.6), dorsocervical fat pad (OR = 3.32), absence of obesity (OR = 0.21) and absence of type 2 diabetes (OR = 0.26), were associated with Cushing’s syndrome; late-night salivary cortisol values were also related (OR = 1.26). However, after multivariable adjustment, researchers found that muscular atrophy (OR = 9.04; 95% CI, 2.36-34.65), osteoporosis (OR = 3.62; 95% CI, 1.16-11.35) and dorsocervical fat (OR = 3.3; 95% CI, 1.52-7.17) remained as independent variables with Cushing’s syndrome.

“Obesity and type 2 diabetes displayed a negative association with [Cushing’s syndrome],” the researchers wrote. “These results might seem paradoxical a priori, but we want to stress that in our analyzed cohort, the prevalence of obesity and diabetes was exceedingly high (likely reflecting the reasons for referral to endocrinology units).”

In receiver operating characteristic (ROC) analysis, researchers determined that a cutoff value of 9.17 nmol/L for late-night salivary cortisol provided the best results, with an area under the curve of 0.893 (P < .001), a sensitivity of 88.5% and specificity of 83.2%.

Researchers developed a risk-scoring system, determining cutoff values from a ROC curve. The estimated area under the ROC curve was 0.93 (P < .001), with a sensitivity of 96.2% and specificity of 82.9%.

“Selecting this cutoff value of four, 271 of 327 subjects (83%) without [Cushing’s syndrome] were correctly identified, while only 1 of 26 [Cushing’s syndrome] cases was missed,” the researchers wrote. “Our model yielded 56 false positives.

“Although all the assessments were performed by specialists (endocrinologists) in our study, this scoring system could be easily tested in independent cohorts and different settings such as primary care or hypertension clinics,” the researchers wrote. “At the very least, our diagnostic prediction model could be used as a framework for future studies and potential improvements in diagnostic performance.” – by Regina Schaffer

Disclosure: Leon-Justel and another researcher report receiving a research grant from Novartis Oncology, Spain.

From http://www.healio.com/endocrinology/adrenal/news/in-the-journals/%7B50d3d398-c8fe-41e9-b815-87626bfe8a4b%7D/screening-tool-accurately-predicts-cushings-syndrome-in-most-at-risk-patients

Cushing’s Syndrome Epidemiology

By Yolanda Smith, BPharm

Cushing’s syndrome is considered to be a rare disorder that results from prolonged exposure to glucocorticoids. However, there are few epidemiological studies to provide adequate data to describe the incidence and prevalence of the condition accurately. Most cases are diagnosed between the ages of 20 and 50, although any individual may be affected at any age.

The presentation of the symptoms of Cushing’s syndrome can vary greatly. In addition, many of the symptoms overlap with those caused by other health conditions, such as metabolic syndrome and polycystic ovary syndrome. This can make the diagnosis of the condition difficult. It is also difficult to establish epidemiological trends in Cushing’s syndrome, because not all cases of the disease are diagnosed. However, it is important that diagnosis is made as soon as possible, because early diagnosis and treatment of the condition are associated with improved morbidity and mortality rates.

Population-based Studies

There are several population-based studies that have reported the incidence and mortality rates of Cushing’s syndrome in certain populations over a discrete period of time.

A study in Denmark followed 166 patients with Cushing’s syndrome for 11 years, finding an incidence of 2 cases per million population per year. Of the 166 patients, 139 had benign disease. There was a mortality rate of 16.5% in the follow-up period of 8 years, with most deaths occurring in the year after the initial diagnosis, often before the initiation of treatment. The causes of death of patients with Cushing’s syndrome in the study included severe infections, cardiac rupture, stroke and suicide.

A study in Spain found 49 cases of Cushing’s syndrome over a period of 18 years, with an incidence of 2.4 cases per million inhabitants per year and a prevalence of 39.1 cases per million. The standard mortality ratio in this study was 3.8, in addition to an increase in morbidity rates.

Incidence

A low incidence of endogenous Cushing’s syndrome was established by the population-based studies outlined above, corresponding to approximately 2 cases per million. Some studies have an estimated incidence as low as 0.7 people per million.

However, the incidence of subclinical Cushing’s syndrome may be underestimated in certain population groups, such as those with osteoporosis, uncontrolled diabetes mellitus or hypertension. For example, of 90 obese patients with uncontrolled diabetes mellitus in one study, three had Cushing’s syndrome. This yielded a prevalence of 3.3%, which is considerably higher than the incidence reported in the population-based studies. However, these findings should be supported by larger studies.

Females are more likely to be affected by Cushing’s syndrome than males, with a risk ratio of approximately 3:1. There does not appear to be a genetic link that involves an ethnic susceptibility to the condition.

Treatment Outcomes

Surgery is the first-line treatment option for most cases of overt disease and remission is achieved in the majority of patients, approximately 65-85%. However, for up to 1 in 5 patients the condition recurs, and the risk does not appear to level off, even after 20 years of follow-up.

The risk of mortality for individuals with Cushing’s syndrome is estimated to be 2-3 times higher than that of the general population, based on epidemiological studies.

Reviewed by Dr Liji Thomas, MD.

From http://www.news-medical.net/health/Cushings-Syndrome-Epidemiology.aspx

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