Growth Hormone Deficiency- Definition, Causes, Symptoms And Treatment

Last Updated on August 10, 2024

Growth hormone deficiency (GHD) or HGH deficiency is the deficiency, absence, or lack of natural growth hormone produced by the pituitary gland to stimulate the growth and development of an individual. HGH deficiency may occur during childhood or later in life.

HGH deficiency is a complex condition affecting various health and well-being aspects. A study published in The Lancet estimates that the prevalence of adult GHD is approximately 1 in 10,000 people, highlighting the importance of understanding this condition. HGH deficiency symptoms can vary widely, making early diagnosis and appropriate HGH deficiency treatment crucial for optimal outcomes.

What is a Growth Hormone?

To understand HGH deficiency well, first, you need to know what the pituitary gland is. The pituitary gland is a pea-sized, small gland responsible for the production of natural growth hormones in the body. This gland is located at the base of the brain and secretes 8 hormones in total. Some of these hormones control body temperature and thyroid function.

Growth hormone (GH) is a complex protein molecule that plays a crucial role in growth, cell reproduction, and regeneration. It’s synthesized, stored, and secreted by somatotropic cells in the anterior pituitary gland. The production and release of GH are regulated by two hypothalamic peptides: growth hormone-releasing hormone (GHRH) and somatostatin.

Your body needs growth hormone even after you enter adulthood. But unfortunately, the amount of GH produced in the body after your teens decreases considerably, leading to various health issues and sometimes GHD. In adulthood, GH maintains your metabolism and body structure. Even adults can develop GHD, but it is not as common as it is in children.

A review highlights the importance of GH in adulthood, noting its role in maintaining bone density, muscle mass, and cardiovascular health. This underscores the potential impact of HGH deficiency on overall well-being throughout life.

Normal Growth Patterns

Growth rates differ significantly from one child to another. But measured in height, the average normal growth is taken to be:

• 0-12 months: 10 inches per year
• 1-2 years: 5 inches per year
• 2-3 years: around 3½ inches per year
• Three years to puberty: 2 to 2½ inches per year

The World Health Organization (WHO) provides growth charts that serve as a reference for normal growth patterns in children. If a child is below the third percentile in height for their age, it may indicate HGH deficiency and warrant further investigation.

A study by Rogol et al. (2000) emphasizes the importance of understanding normal growth patterns in diagnosing GHD. The authors note that growth velocity, rather than absolute height, can be a more sensitive indicator of potential HGH deficiency, especially in the early stages.

Causes of HGH Deficiency

Growth hormone deficiency takes place when the pituitary gland doesn’t produce much growth hormone in the body. The causes may include infections, trauma, genetics, radiation therapy, and tumors. Genes that may be involved include BTK, GH1, or GHRHR.

GHD in children often has no identifiable causes, while adult-onset GHD is mainly due to pituitary tumors and their subsequent treatment. More causes may include:

• Mutations of specific genes (e.g., BTK, GH1, or GHRHR)
• Congenital malformations involving the pituitary (e.g., posterior pituitary ectopia, septo-optic dysplasia)
• Autoimmune inflammation
• Chronic renal deficiency
• Congenital diseases (e.g., Turner syndrome, Prader-Willi syndrome)
• Ischemic infarction from low blood pressure
• Damage to the pituitary from radiation to the head, trauma, surgery, or intracranial disease

A comprehensive review by Alatzoglou et al. (2014) provides insights into the genetic causes of congenital GHD, highlighting the complexity of the condition and the various genes involved.

There are indeed many rare diseases that resemble growth hormone deficiency, showing similar symptoms like facial appearance, growth failure, delayed bone age, and low IGF levels. GH testing may elicit high or normal levels of growth hormone in the blood, indicating that the issue is not due to a deficiency of growth hormone but rather a low sensitivity to its action. Insensitivity to growth hormone is termed Laron dwarfism, but for about 15 years or so, many different types of GH resistance have been observed, mainly involving mutations of GH binding receptors.

Laron syndrome, a rare form of dwarfism caused by GH resistance, was first described by Zvi Laron in 1966. This condition provides valuable insights into the mechanisms of GH action and the potential consequences of severe HGH deficiency.

HGH Deficiency Symptoms

Recognizing HGH deficiency symptoms is crucial for early diagnosis and treatment. The manifestations can differ between children and adults:

In Children:

• Shorter height compared to peers
• Young, round faces
• Increased body fat, especially around the belly
• Delayed puberty (if GHD develops later in childhood)
• Halted sexual development in some cases

A study by Grimberg et al. (2016) found that children with GHD may also experience:

• Delayed tooth development
• Thin, fragile hair
• Impaired nail growth
• Reduced muscle mass

Many teens with GHD experience low confidence and self-esteem due to developmental delays like slow maturing rate and short stature. For instance, young women may not develop fully grown breasts, and young men’s voices may not change.

In Adults:

• Decreased bone strength
• Fatigue or lack of strength and stamina
• Sensitivity to cold and hot temperatures
• High levels of fat in the blood and high cholesterol
• Increased risk of heart disease and diabetes

There are studies that identified the following HGH deficiency symptoms in adults:

• Reduced muscle mass
• Decreased exercise capacity
• Impaired concentration and memory
• Depression and anxiety
• Increased abdominal fat

It’s crucial to understand that not all individuals with GHD will have the same or similar symptoms. While some may have just 1-2 signs, others can have multiple issues.

Research by Melmed (2013) highlights the variability in HGH deficiency symptoms, noting that the severity and combination of symptoms can differ significantly among individuals. This variability underscores the importance of comprehensive evaluation in diagnosing HGH deficiency.

Diagnosis of HGH Deficiency

Before a GHD diagnosis can be made, the doctor may have to rule out other health disorders like short stature or thyroid hormone deficiency. Apart from a detailed physical examination and medical history, diagnostic processes for GHD may include:

• Monitoring the growth of a child over time
• Blood tests
• Scanning the pituitary to detect abnormalities

A blood test can indicate the level of GH in your body. However, GH levels fluctuate significantly throughout the day and night. Therefore, a single blood test with lower-than-average results is insufficient evidence to make the right diagnosis. Thyroid and kidney function tests can also show how the body uses and produces hormones.

The Endocrine Society’s clinical practice guidelines recommend the following additional diagnostic tools:

• Stimulation tests (e.g., insulin tolerance test, arginine stimulation test)
• Measurement of insulin-like growth factor 1 (IGF-1) levels
• Magnetic Resonance Imaging (MRI) of the pituitary gland**

A study by Yuen et al. (2016) explores the use of novel biomarkers in diagnosing GHD, potentially offering more accurate and less invasive diagnostic methods in the future.

HGH Deficiency Treatment

Since the 1980s, synthetic GH has been used successfully to treat both children and adults with GHD. Before synthetic GH, natural growth hormone extracted from cadavers was used for treating GHD.

Growth hormone is typically administered through daily injections, mainly into the body’s fatty tissues like the back of the arms, buttocks, or thighs. It is effective when taken as a daily treatment.

A landmark study by Attanasio et al. (2002) demonstrated the long-term efficacy and safety of GH replacement therapy in adults with GHD, showing improvements in body composition, bone density, and quality of life.

HGH deficiency treatment may also include:

• Gonadal steroid replacement in patients with multiple pituitary hormone deficiencies
• Psychological support and counseling
• Regular monitoring and dose adjustments

While injections have their own set of side effects, HGH supplements have emerged as an alternative. These supplements are marketed as safe and natural, with potential benefits for users. However, it’s important to note that the efficacy and safety of these supplements are not well-established, and they should not be used as a substitute for prescribed HGH deficiency treatment without medical supervision.

A review by Boguszewski and Boguszewski (2019) explores emerging treatment options for GHD, including long-acting GH preparations and GH secretagogues. These new approaches aim to improve treatment adherence and quality of life for patients with HGH deficiency.

Home Care and Lifestyle Management

As HGH deficiency can cause a lack of strength and energy, patients should:

• Maintain a balanced diet
• Engage in regular exercise
• Ensure adequate sleep

Follow-up care with an endocrinologist (a doctor specializing in hormones) is advisable. It’s recommended to start HGH deficiency treatment as soon as you are diagnosed, as earlier treatment often leads to better results and improved health outcomes.

A study by Reed et al. (2013) emphasized the importance of a multidisciplinary approach in managing GHD, including:

• Nutritional counseling
• Physical therapy
• Regular bone density screenings
• Cardiovascular risk assessment

Research by Hoffman et al. (2017) highlights the potential benefits of exercise in individuals with GHD, noting improvements in body composition, muscle strength, and cardiovascular health. This underscores the importance of lifestyle factors in managing HGH deficiency symptoms.

Conclusion

HGH deficiency is a complex condition that requires prompt diagnosis and appropriate treatment. By understanding the symptoms, causes, and available treatments, individuals with GHD can work with their healthcare providers to develop effective management strategies and improve their quality of life.

This detailed review by Bidlingmaier et al. (2021) provides an updated perspective on the diagnosis and treatment of GHD, emphasizing the need for individualized approaches and ongoing research to optimize outcomes for patients with HGH deficiency.

References:

1. Grimberg, A., et al. (2016). Guidelines for Growth Hormone and Insulin-Like Growth Factor-I Treatment in Children and Adolescents: Growth Hormone Deficiency, Idiopathic Short Stature, and Primary Insulin-Like Growth Factor-I Deficiency. The Journal of Clinical Endocrinology & Metabolism, 101(3), 804-834.
2. Molitch, M. E., et al. (2011). Evaluation and Treatment of Adult Growth Hormone Deficiency: An Endocrine Society Clinical Practice Guideline. The Journal of Clinical Endocrinology & Metabolism, 96(6), 1587-1609.
3. Attanasio, A. F., et al. (2002). Adult Growth Hormone (GH)-Deficient Patients Demonstrate Heterogeneity between Childhood Onset and Adult Onset before and during Human GH Treatment. The Journal of Clinical Endocrinology & Metabolism, 87(5), 2624-2632.
4. Reed, M. L., et al. (2013). Adult Growth Hormone Deficiency – Benefits, Side Effects, and Risks of Growth Hormone Replacement. Frontiers in Endocrinology, 4, 64.
5. Alatzoglou, K. S., et al. (2014). Genetics of Isolated Growth Hormone Deficiency. Journal of Clinical Research in Pediatric Endocrinology, 6(4), 169-174.
6. Gupta, V. (2011). Adult growth hormone deficiency. Indian Journal of Endocrinology and Metabolism, 15(Suppl3), S197-S202.
7. Rogol, A. D., et al. (2000). Growth and pubertal development in children and adolescents: effects of diet and physical activity. The Journal of Clinical Endocrinology & Metabolism, 85(11), 3990-3997.
8. Melmed, S. (2013). Idiopathic adult growth hormone deficiency. New England Journal of Medicine, 369(19), 1836-1846.
9. Yuen, K. C., et al. (2016). Clinical review: Is lack of recombinant growth hormone (GH)-releasing hormone in the United States a setback or time for a new paradigm for evaluating adult GH deficiency? The Journal of Clinical Endocrinology & Metabolism, 101(1), 1-7.
10. Boguszewski, C. L., & Boguszewski, M. C. S. (2019). Growth Hormone’s Links to Cancer. Endocrine Reviews, 40(2), 558-574.
11. Hoffman, A. R., et al. (2017). Growth hormone and exercise. Growth Hormone & IGF Research, 34, 1-7.
12. Bidlingmaier, M., et al. (2021). Growth hormone deficiency in adults. Nature Reviews Endocrinology, 17(3), 171-189.