Veterinary Endocrinology: Diagnosing and Managing Hormonal Disorders

Veterinary endocrinology is the branch of veterinary medicine that studies the endocrine glands and the hormones they produce, focusing on how hormonal imbalances cause disease in animals. This field covers the diagnosis and management of conditions such as diabetes mellitus, hyperadrenocorticism (Cushing's disease), hypoadrenocorticism (Addison's disease), thyroid disorders, and pituitary dysfunction. For students, researchers, life-science professionals, and informed general readers, understanding veterinary endocrinology requires knowledge of the diagnostic tests used to measure hormone concentrations, the treatment protocols available for common endocrine disorders, and the specialized career path that leads to board certification in this discipline. This article describes the diagnostic approach to endocrine disease in animals, the management strategies for the most frequently encountered hormonal disorders, and the training pathway for veterinary endocrinologists.

The Scope of Veterinary Endocrinology

Veterinary endocrinology addresses disorders of the endocrine system in domestic, companion, and exotic animals. The endocrine system consists of glands that secrete hormones directly into the bloodstream, where these chemical messengers travel to target tissues and regulate metabolism, growth, reproduction, stress responses, and fluid balance. When a gland produces too much or too little hormone, or when target tissues fail to respond appropriately, systemic illness results.

The clinical presentation of endocrine disease in animals is often nonspecific. Weight changes, alterations in appetite, increased thirst and urination, changes in coat or skin condition, lethargy, and behavioral changes are common across many endocrinopathies. These signs overlap with those of nonendocrine diseases, which makes diagnostic testing essential. A veterinary endocrinologist applies knowledge of hormone physiology, assay methodology, and disease pathophysiology to interpret test results and design treatment plans.

Endocrine disorders occur across species. In dogs, the most common endocrinopathies include diabetes mellitus, hyperadrenocorticism, hypothyroidism, and hypoadrenocorticism. In cats, hyperthyroidism and diabetes mellitus are frequently diagnosed. Horses develop pituitary pars intermedia dysfunction (PPID) and insulin dysregulation, which are components of equine metabolic syndrome. Endocrine disorders also affect nonhuman primates, although they remain underreported in this group. A comprehensive review of naturally occurring endocrine disorders in nonhuman primates found that diagnoses were frequently made as incidental findings after standard histological examination, with no clinical signs noted in most cases and unremarkable endocrine organs on gross pathology [23]. This observation highlights the importance of systematic diagnostic approaches and the potential for endocrine disease to go unrecognized in some species.

The burden of endocrine and metabolic disease extends beyond veterinary medicine. Population-level studies in human medicine document rising incidence of autoimmune disorders, which include several endocrine conditions such as type 1 diabetes and autoimmune thyroid disease. A population-based cohort study of 22 million individuals in the UK found that among those with a new diagnosis of at least one autoimmune disease, the mean age at diagnosis was 54 years and 63.9 percent of cases occurred in women [7]. While these data come from human medicine, they illustrate the scale of endocrine-related autoimmune disease and the value of understanding hormonal disorders across species.

Core Principles of Endocrine Diagnosis

Endocrine diagnosis rests on the measurement of hormone concentrations in blood, urine, or other body fluids, combined with functional testing that assesses the dynamic response of the endocrine system. Several principles guide the interpretation of endocrine tests.

Hormone Assays and Their Limitations

Hormone concentrations are measured using immunoassays, which rely on antibodies that bind to specific hormones. These assays include enzyme-linked immunosorbent assays (ELISA), radioimmunoassay (RIA), and chemiluminescent immunoassays. Each method has different sensitivity, specificity, and reference ranges. Assay results can vary between laboratories, so serial monitoring of an individual animal should ideally be performed using the same laboratory and assay method.

Endogenous hormone secretion is often pulsatile or diurnal. A single hormone measurement may not reflect the average hormone status of the animal. For example, cortisol is secreted in episodic bursts and is influenced by stress, so a single cortisol measurement has limited diagnostic value for hyperadrenocorticism. Dynamic function tests, which involve administering a stimulating or suppressing agent and measuring the hormone response over time, provide more reliable diagnostic information.

Baseline Testing and Dynamic Function Tests

Baseline tests measure hormone concentrations at a single point in time. These tests are useful for screening but often require confirmation with dynamic testing. Examples include measurement of total thyroxine (T4) for thyroid status and measurement of fasting blood glucose for diabetes mellitus.

Dynamic function tests evaluate the integrity of the hypothalamic-pituitary-target gland axis. These tests include:

• Adrenocorticotropic hormone (ACTH) stimulation test for hypoadrenocorticism and hyperadrenocorticism
• Low-dose dexamethasone suppression test for hyperadrenocorticism
• Thyroid-stimulating hormone (TSH) stimulation test for hypothyroidism
• Glucose tolerance tests for insulin dysregulation

The choice of test depends on the suspected disorder, the species, the clinical signs, and the availability of the assay. Test protocols must be followed precisely because timing of sample collection affects interpretation.

Reference Ranges and Individual Variation

Reference ranges are established from populations of healthy animals and are influenced by age, breed, sex, reproductive status, and laboratory methodology. A hormone concentration within the reference range does not exclude disease, and a concentration outside the range does not confirm disease. The clinician must integrate laboratory results with history, physical examination findings, and other diagnostic information.

Common Endocrine Disorders in Animals

Several endocrine disorders account for the majority of cases seen in veterinary practice. Each disorder has characteristic clinical signs, diagnostic findings, and management strategies.

Diabetes Mellitus

Diabetes mellitus results from absolute or relative insulin deficiency, leading to hyperglycemia and glucosuria. In dogs, diabetes mellitus is usually insulin-dependent and requires lifelong insulin therapy. In cats, diabetes mellitus is often type 2-like, with insulin resistance and progressive beta-cell dysfunction, and some cats achieve diabetic remission with appropriate management.

Clinical signs include polyuria, polydipsia, polyphagia, and weight loss. Diagnosis is based on persistent fasting hyperglycemia and glucosuria, with documentation of elevated fructosamine or glycated hemoglobin to distinguish diabetes from stress-induced hyperglycemia. Management involves insulin administration, dietary modification, weight management, and monitoring of blood glucose curves.

Diabetes mellitus has secondary effects on multiple organ systems. In canine ophthalmic patients, cataracts are a common complication of diabetes mellitus, and retinopathy, metabolic disorders, and systemic hypertension are common problems in animals with this condition [24]. Ocular changes can be the first signs of serious systemic disease, and early diagnosis of ophthalmic symptoms can help identify the primary endocrine cause and allow effective treatment to begin [24].

Hyperadrenocorticism (Cushing's Disease)

Hyperadrenocorticism results from chronic excess of cortisol. In dogs, the condition is most commonly caused by a pituitary adenoma that secretes excess ACTH (pituitary-dependent hyperadrenocorticism), or less commonly by an adrenal tumor that secretes cortisol autonomously. Clinical signs include polyuria, polydipsia, polyphagia, abdominal distension, muscle weakness, alopecia, and calcinosis cutis.

Diagnosis involves screening tests such as the urine cortisol-to-creatinine ratio, followed by confirmatory testing with the low-dose dexamethasone suppression test or the ACTH stimulation test. Differentiation between pituitary-dependent and adrenal-dependent disease requires measurement of endogenous ACTH concentration or imaging of the adrenal glands.

Management options include medical therapy with trilostane or mitotane, or surgical removal of an adrenal tumor. Patients with hyperadrenocorticism may develop complications secondary to hyperlipidemia and hypertension, and these comorbidities require monitoring and management [24].

Hypoadrenocorticism (Addison's Disease)

Hypoadrenocorticism results from deficiency of mineralocorticoids and glucocorticoids produced by the adrenal cortex. Clinical signs include lethargy, weakness, vomiting, diarrhea, weight loss, and collapse. The condition can present as an acute adrenal crisis with hypovolemic shock, bradycardia, and electrolyte abnormalities including hyponatremia and hyperkalemia.

Diagnosis is based on the ACTH stimulation test, which shows a blunted cortisol response. Management involves replacement of mineralocorticoids and glucocorticoids, with dose adjustments based on clinical response and electrolyte monitoring.

Hypothyroidism

Hypothyroidism is a common endocrinopathy in dogs, resulting from deficiency of thyroid hormones. Clinical signs include weight gain, lethargy, hair loss, skin changes, and cold intolerance. Diagnosis is based on measurement of total T4, free T4 by equilibrium dialysis, and endogenous TSH concentration. A low total T4 with elevated TSH supports the diagnosis.

Management involves lifelong thyroid hormone replacement therapy with levothyroxine, with dose adjustments based on clinical response and monitoring of T4 concentrations.

Feline Hyperthyroidism

Hyperthyroidism is the most common endocrinopathy in older cats, resulting from excessive production of thyroid hormones, usually due to a benign adenomatous hyperplasia of the thyroid gland. Clinical signs include weight loss despite increased appetite, hyperactivity, vomiting, and increased thirst and urination.

Diagnosis is based on elevated total T4 concentration, with additional testing such as free T4 measurement or thyroid scintigraphy in cases with borderline results. Management options include medical therapy with methimazole, surgical thyroidectomy, radioactive iodine therapy, or dietary management with an iodine-restricted diet.

Equine Pituitary Pars Intermedia Dysfunction and Insulin Dysregulation

PPID is a common endocrine disorder of older horses, characterized by enlargement of the pars intermedia of the pituitary gland and excess production of proopiomelanocortin-derived peptides. Clinical signs include hirsutism, laminitis, muscle wasting, lethargy, and increased thirst and urination. Insulin dysregulation is a component of equine metabolic syndrome and is characterized by hyperinsulinemia and insulin resistance.

Diagnosis of PPID involves measurement of basal ACTH concentration or dynamic testing with the thyrotropin-releasing hormone (TRH) stimulation test. Diagnosis of insulin dysregulation involves measurement of fasting insulin concentration or dynamic testing with an oral sugar test or glucose tolerance test.

Management of PPID involves treatment with pergolide, a dopamine agonist, combined with management of laminitis and associated conditions. Management of insulin dysregulation focuses on dietary restriction, exercise, and treatment of underlying conditions.

The presence of endocrine disorders in horses may influence responses to other treatments. A study of ivermectin performance in horses diagnosed with equine endocrine disorders found high efficacy of ivermectin against cyathostomins, with mean egg count reduction at or above 99.7 percent in all groups at two weeks post treatment [22]. Egg reappearance was documented at six and seven weeks in the insulin dysregulation and PPID plus insulin dysregulation groups, respectively, whereas the PPID and healthy control groups both had egg reappearance at eight weeks [22]. The expected egg reappearance period for ivermectin is eight to ten weeks, meaning that two of the groups displayed a shortened egg reappearance period [22]. This finding suggests that horses with endocrine disorders may require closer monitoring of parasite control programs.

Diagnostic Tests in Veterinary Endocrinology

The following table summarizes common endocrine tests and the hormones or parameters they measure. This table serves as a practical reference for clinicians and students.

The Role of the Veterinary Endocrinologist

The veterinary endocrinologist is a specialist who has completed advanced training in endocrinology and related disciplines. This specialist provides diagnostic and therapeutic expertise for complex endocrine cases, interprets challenging laboratory results, and contributes to research and education in the field.

Clinical Responsibilities

The veterinary endocrinologist manages patients with endocrine disorders that are difficult to diagnose or treat. This includes cases where initial therapy has failed, where multiple endocrine disorders coexist, or where the clinical presentation is atypical. The endocrinologist also advises primary care veterinarians on test selection, interpretation, and treatment adjustments.

Diagnostic Oversight

Endocrine testing requires careful attention to sample handling, timing, and assay methodology. The endocrinologist ensures that samples are collected and processed correctly, that appropriate tests are selected for the clinical question, and that results are interpreted in the context of the individual patient. This oversight is particularly important for dynamic function tests, where protocol deviations can invalidate results.

Research and Education

Veterinary endocrinologists contribute to the scientific literature on endocrine disease in animals. Research areas include the pathophysiology of endocrine disorders, evaluation of diagnostic tests, assessment of treatment outcomes, and investigation of endocrine disease in less commonly studied species. The endocrinologist also educates veterinary students, residents, and practicing veterinarians through lectures, publications, and clinical consultations.

Career Path to Veterinary Endocrinology

Becoming a veterinary endocrinologist requires completion of a veterinary degree, followed by advanced residency training and board certification. The pathway is demanding and requires a strong foundation in basic sciences, clinical medicine, and research methodology.

Veterinary Degree

The first step is completion of a Doctor of Veterinary Medicine (DVM) or equivalent degree from an accredited veterinary school. Veterinary education covers anatomy, physiology, pharmacology, pathology, and clinical medicine, providing the foundation for specialized training. The U.S. Bureau of Labor Statistics provides information on the broader category of life, physical, and social science occupations, which includes veterinary and related professions [1]. Healthcare occupations, which encompass veterinary medicine, are also described in federal occupational resources [2].

Residency Training

After earning the veterinary degree, the aspiring endocrinologist completes a residency program in internal medicine or a related specialty, with focused training in endocrinology. Residency programs are typically three years in duration and include supervised clinical practice, didactic instruction, and research. The O*NET OnLine database, maintained by the U.S. Department of Labor, provides detailed information on the knowledge, skills, and abilities required for various occupations, including those in veterinary medicine [3].

Board Certification

Board certification in veterinary internal medicine, with a focus on endocrinology, is achieved through the American College of Veterinary Internal Medicine (ACVIM) or equivalent certifying bodies in other countries. Certification requires completion of an approved residency, submission of a case log and research portfolio, and passing a rigorous examination. Board-certified specialists are recognized as experts in their field and are eligible for faculty positions, specialty practice, and leadership roles.

Continuing Education and Research Training

Endocrinology is a rapidly evolving field, and the specialist must stay current with advances in diagnostic testing, treatment protocols, and understanding of disease mechanisms. Many veterinary endocrinologists pursue additional research training, such as a PhD or postdoctoral fellowship. The National Institutes of Health Office of Intramural Training and Education provides information on research training opportunities in biomedical sciences, which can be relevant for veterinarians pursuing research careers [4]. The National Center for Biotechnology Information and PubMed provide access to the scientific literature that supports evidence-based practice in endocrinology [5][6].

Practical Implementation of Endocrine Testing

Implementing endocrine testing in clinical practice requires attention to protocol, sample handling, and interpretation. The following steps provide a framework for the assessment of a patient with suspected endocrine disease.

Step 1: History and Physical Examination

A thorough history and physical examination guide the selection of diagnostic tests. Key historical information includes signalment, presenting complaints, duration of signs, progression, response to previous treatments, and concurrent medications. Physical examination findings may reveal characteristic features of specific endocrinopathies, such as alopecia and abdominal distension in hyperadrenocorticism, or goiter in hyperthyroidism.

Step 2: Baseline Laboratory Testing

Baseline testing includes a complete blood count, serum biochemistry profile, and urinalysis. These tests identify abnormalities that support or exclude endocrine disease and detect concurrent conditions that may complicate management. For example, hyperglycemia and glucosuria support a diagnosis of diabetes mellitus, while hyponatremia and hyperkalemia suggest hypoadrenocorticism.

Step 3: Confirmatory Endocrine Testing

Confirmatory testing is selected based on the suspected disorder and the results of baseline testing. Dynamic function tests are performed when baseline tests are equivocal or when confirmation is required. The clinician must follow the test protocol precisely, including the timing of sample collection and the dose and route of any administered agents.

Step 4: Interpretation and Diagnosis

Test results are interpreted in the context of the individual patient, considering reference ranges, assay methodology, and the pretest probability of disease. The clinician integrates laboratory findings with history and physical examination to establish a diagnosis and develop a treatment plan.

Step 5: Treatment and Monitoring

Treatment is initiated based on the diagnosis, and the patient is monitored at regular intervals. Monitoring includes clinical assessment, measurement of hormone concentrations, and evaluation of treatment efficacy and adverse effects. Dose adjustments are made based on monitoring results.

Step 6: Escalation to Specialist Care

Cases that are difficult to diagnose, fail to respond to treatment, or require advanced diagnostic procedures should be referred to a veterinary endocrinologist or internal medicine specialist. Escalation criteria include persistent clinical signs despite appropriate treatment, unexpected test results, suspected multiple endocrine disorders, and the need for advanced imaging or specialized assays.

Records and Measurements in Endocrine Case Management

Accurate record keeping is essential for the management of endocrine disease. The following records should be maintained for each patient:

• Signalment and history
• Physical examination findings
• Baseline laboratory results
• Endocrine test results, including the specific assay used and the laboratory that performed the test
• Treatment protocols, including drug, dose, route, and frequency
• Monitoring results, including hormone concentrations and clinical assessments
• Adverse events and complications
• Communication with the owner and with other veterinary professionals

Serial measurements of hormone concentrations are used to monitor treatment efficacy and adjust doses. For example, in dogs with hyperadrenocorticism treated with trilostane, cortisol concentrations are measured before and after medication administration to guide dose adjustments. In diabetic animals, serial blood glucose curves and fructosamine concentrations assess glycemic control.

Common Failure Patterns in Endocrine Diagnosis and Management

Several recurring problems can compromise the diagnosis and management of endocrine disease. Recognizing these failure patterns helps clinicians avoid errors and improve outcomes.

Inappropriate Test Selection

Selecting a test that does not answer the clinical question wastes resources and can lead to misdiagnosis. For example, measuring total T4 in a dog with nonthyroidal illness may produce a low result that does not indicate hypothyroidism. The clinician must understand the indications, limitations, and interpretation of each test.

Protocol Deviations

Dynamic function tests require precise timing and dosing. Deviations from the protocol, such as collecting samples at the wrong time or administering the wrong dose of a stimulating agent, invalidate the test and require repetition. The clinician must ensure that staff are trained in test protocols and that sample collection is carefully timed.

Misinterpretation of Results

Endocrine test results are influenced by many factors, including stress, concurrent illness, and medications. Interpreting results without considering these factors can lead to incorrect diagnoses. For example, stress hyperglycemia in cats can be mistaken for diabetes mellitus, and a low cortisol response to ACTH stimulation can be caused by recent glucocorticoid administration.

Inadequate Monitoring

Endocrine disorders require lifelong management and regular monitoring. Failure to monitor treatment efficacy and adverse effects can result in inadequate control or complications. For example, diabetic animals require regular assessment of glycemic control, and animals treated with trilostane require monitoring of electrolytes and cortisol concentrations.

Failure to Consider Comorbidities

Endocrine disorders often coexist with other conditions. For example, animals with hyperadrenocorticism may develop hypertension, hyperlipidemia, and urinary tract infections, and animals with diabetes mellitus may develop cataracts, pancreatitis, and urinary tract infections [24]. Failure to identify and manage comorbidities compromises outcomes.

Welfare and Safety Considerations

Endocrine disorders can cause significant morbidity, and treatment can be associated with adverse effects. The clinician must balance the benefits of treatment against the risks and consider the welfare of the animal throughout the diagnostic and therapeutic process.

Stress and Handling

Diagnostic testing and treatment can be stressful for animals. Stress affects hormone concentrations, particularly cortisol, and can interfere with test interpretation. The clinician should minimize stress during sample collection and consider the effects of stress when interpreting results.

Adverse Effects of Treatment

Endocrine treatments can cause adverse effects. For example, insulin therapy can cause hypoglycemia, trilostane can cause electrolyte imbalances and gastrointestinal signs, and methimazole can cause vomiting, anorexia, and blood dyscrasias. The clinician must educate owners about potential adverse effects and provide instructions for monitoring and emergency care.

Zoonotic and Occupational Safety

Some endocrine disorders are associated with conditions that have zoonotic potential, and some treatments require careful handling. The clinician should follow standard precautions for infection control and safe handling of medications.

Endocrine Disrupting Chemicals

Exposure to endocrine disrupting chemicals (EDCs) can affect hormone function in animals and humans. A study of maternal exposure to domestic hair cosmetics and occupational endocrine disruptors found an association between potential maternal occupational exposure to EDCs and household use of hair cosmetics during early pregnancy and the incidence of hypospadias in offspring [20]. While this study was conducted in human medicine, it illustrates the potential for environmental exposures to affect endocrine function and the importance of considering environmental factors in endocrine disease.

Limitations of Current Knowledge

Veterinary endocrinology has advanced significantly, but important limitations remain. Endocrine disorders in some species are underreported, diagnostic tests have imperfect sensitivity and specificity, and treatment protocols are not always supported by robust evidence.

Underreporting in Some Species

Endocrine disorders in nonhuman primates and other exotic species remain underreported, and there is no standard procedure for diagnosing, monitoring, or treating endocrine disorders in these species [23]. More research is needed to evaluate diagnostic and treatment procedures and establish risk factors [23].

Assay Limitations

Immunoassays for hormone measurement have limitations, including cross-reactivity with related compounds, interference from endogenous antibodies, and variability between laboratories. The clinician must be aware of these limitations and interpret results accordingly.

Evidence Gaps

Some treatment protocols are based on clinical experience instead of controlled trials. The clinician should critically evaluate the evidence supporting treatment recommendations and consider the individual patient's circumstances.

Professional Escalation Criteria

The following situations warrant referral to a veterinary endocrinologist or internal medicine specialist:

• Persistent clinical signs despite appropriate treatment for a confirmed endocrine disorder
• Suspected endocrine disorder that cannot be confirmed with standard diagnostic testing
• Multiple endocrine disorders in the same patient
• Endocrine disorder in a species with limited published information on diagnosis and treatment
• Complications of endocrine disease or treatment that are difficult to manage
• Need for advanced diagnostic procedures, such as adrenal imaging, thyroid scintigraphy, or specialized assays
• Poor response to treatment or unexpected treatment failure

Frequently Asked Questions

What is the difference between a veterinary endocrinologist and a general practice veterinarian?

A veterinary endocrinologist is a specialist who has completed a veterinary degree, a residency in internal medicine with focused training in endocrinology, and board certification through a recognized certifying body. The endocrinologist has advanced knowledge of hormone physiology, diagnostic testing, and treatment of endocrine disorders. General practice veterinarians diagnose and manage common endocrine conditions, but they refer complex cases to specialists for advanced diagnostic testing and treatment.

What are the most common endocrine disorders in dogs?

The most common endocrine disorders in dogs are diabetes mellitus, hyperadrenocorticism (Cushing's disease), hypothyroidism, and hypoadrenocorticism (Addison's disease). Each condition has characteristic clinical signs and requires specific diagnostic testing and management.

How is diabetes mellitus diagnosed in cats?

Diabetes mellitus in cats is diagnosed based on persistent hyperglycemia and glucosuria, with documentation of elevated fructosamine or glycated hemoglobin to distinguish diabetes from stress-induced hyperglycemia. Clinical signs include polyuria, polydipsia, polyphagia, and weight loss.

What is the ACTH stimulation test and when is it used?

The ACTH stimulation test measures cortisol concentrations before and after administration of synthetic ACTH. It is used to diagnose hypoadrenocorticism, where the cortisol response is blunted, and to monitor treatment of hyperadrenocorticism with trilostane or mitotane.

What is pituitary pars intermedia dysfunction in horses?

Pituitary pars intermedia dysfunction (PPID) is a common endocrine disorder of older horses, characterized by enlargement of the pars intermedia of the pituitary gland and excess production of proopiomelanocortin-derived peptides. Clinical signs include hirsutism, laminitis, muscle wasting, lethargy, and increased thirst and urination. Diagnosis involves measurement of basal ACTH concentration or dynamic testing, and management involves treatment with pergolide.

Can endocrine disorders affect the eyes of animals?

Yes, endocrine disorders can cause secondary ophthalmic disease. Cataracts, retinopathy, metabolic disorders, and systemic hypertension are common problems in animals with diabetes mellitus [24]. Patients with hyperadrenocorticism may develop complications secondary to hyperlipidemia and hypertension, and animals with hyperthyroidism may have ophthalmic problems associated with systemic hypertension and subsequent retinal bleeding or detachment [24].

What training is required to become a veterinary endocrinologist?

Becoming a veterinary endocrinologist requires completion of a veterinary degree, followed by a residency program in internal medicine with focused training in endocrinology, and board certification through a recognized certifying body. Many veterinary endocrinologists also pursue research training, such as a PhD or postdoctoral fellowship.

How are endocrine test results interpreted in the context of the individual patient?

Endocrine test results are interpreted by considering reference ranges, assay methodology, the pretest probability of disease, and the effects of stress, concurrent illness, and medications. The clinician integrates laboratory findings with history and physical examination to establish a diagnosis and develop a treatment plan.

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References and Further Reading

• Life, Physical, and Social Science Occupations. U.S. Bureau of Labor Statistics.
• Healthcare Occupations. U.S. Bureau of Labor Statistics.
• O*NET OnLine. U.S. Department of Labor.
• Office of Intramural Training and Education. National Institutes of Health.
• NCBI Literature Resources. National Center for Biotechnology Information.
• PubMed. National Library of Medicine.
• Incidence, prevalence, and co-occurrence of autoimmune disorders over time and by age, sex, and socioeconomic status: a population-based cohort study of 22 million individuals in the UK.. Lancet (London, England), 2023.
• Global burden of chronic respiratory diseases and risk factors, 1990-2019: an update from the Global Burden of Disease Study 2019.. EClinicalMedicine, 2023.
• Global, regional, and national burden of stroke and its risk factors, 1990-2021: a systematic analysis for the Global Burden of Disease Study 2021.. The Lancet. Neurology, 2024.
• Global, regional, and national burden of chronic kidney disease in adults, 1990-2023, and its attributable risk factors: a systematic analysis for the Global Burden of Disease Study 2023.. Lancet (London, England), 2025.
• Forecasting the effects of smoking prevalence scenarios on years of life lost and life expectancy from 2022 to 2050: a systematic analysis for the Global Burden of Disease Study 2021.. The Lancet. Public health, 2024.
• Burden of 375 diseases and injuries, risk-attributable burden of 88 risk factors, and healthy life expectancy in 204 countries and territories, including 660 subnational locations, 1990-2023: a systematic analysis for the Global Burden of Disease Study 2023.. Lancet (London, England), 2025.
• The global, regional, and national burden of cancer, 1990-2023, with forecasts to 2050: a systematic analysis for the Global Burden of Disease Study 2023.. Lancet (London, England), 2025.
• Global burden of 292 causes of death in 204 countries and territories and 660 subnational locations, 1990-2023: a systematic analysis for the Global Burden of Disease Study 2023.. Lancet (London, England), 2025.
• Addressing Childhood Obesity in Children in Need in Greece: Policy Implementers' Knowledge, Perceptions and Lessons for Effective Implementation.. 2025.
• Social Determinants of Health Influence on Trans and Gender-Diverse People: A Qualitative Photovoice Study. 2026.
• Education Reform using Common Career Selective Programme (CCSP) to Promote Education-for-All (EFA).. 2025.
• Community-based HIV prevention services for transgender people in Ukraine: current situation and potential for improvement.. 2023.
• Jewish anatomic pathologists in the time of Italian Racial Laws.. 2022.
• Maternal Exposure to Domestic Hair Cosmetics and Occupational Endocrine Disruptors Is Associated with a Higher Risk of Hypospadias in the Offspring.. 2016.
• 2024 Diabetes Technology Meeting Abstracts. 2025.
• Ivermectin performance in horses diagnosed with equine endocrine disorders.. Veterinary parasitology, 2024.
• Naturally Occurring Endocrine Disorders in Non-Human Primates: A Comprehensive Review. Animals, 2022.
• Canine ophthalmic patients with endocrine and metabolic disorders - a review. Bulgarian Journal of Veterinary Medicine, 2023.
• A landmark contribution to poultry science-A possible mode of action of sulfamethazine on the reproductive system of Leghorn cockerels. Poultry Science, 2009.

This article is educational and does not replace institutional policy, professional advice, or applicable safety and regulatory requirements.