Metabolic Bone Disease Explained
Fractures are a common complication caused by bone diseases. In the U.S., around 1.5 million Americans experience a fracture due to bone disease every year. Although this is usually due to osteoporosis, several other bone diseases are important to take note of. Some bone diseases are not given focus due to under-diagnosis and under-reporting. In this article, you will learn about metabolic bone disease, its causes, and how it is diagnosed and treated.
What is Metabolic Bone Disease?
The term metabolic bone disease is a broad term. It includes various disorders that lead to bone defects and malformations due to the imbalance of minerals such as calcium, phosphorus, and magnesium in the body. Each substance can regulate another through biochemical pathways and hormones, and the deficiency of one can affect the others. The imbalance of these compounds in the body can lead to various symptoms observed in patients with the disease.
Common diseases that belong to this group include primary hyperparathyroidism, osteogenesis imperfecta, Paget’s disease, osteoporosis, and osteomalacia or rickets.
What Are the Causes of Metabolic Bone Disease?
Because metabolic bone disease is a broad term, each disorder has a specific cause. However, the endpoint is the imbalance in the substances and minerals that affect the strength and integrity of bone. The skeletal system is in a constant state of renewal and remodeling to ensure a healthy bone matrix and maintain maximal bone strength to sustain a person's daily activities and tasks.
Different metabolic bone diseases are a result of the disruption of these body systems:
- Osteoporosis: one of the most common forms of metabolic bone disease, has a multifactorial cause that reduces bone mass and density.
- Osteogenesis imperfecta: a genetic condition resulting from mutations in genes that produce collagen, leading to brittle bones, also known as brittle bone disease.
- Vitamin D deficiency: if prolonged this will lead to weak bones. In children, this is called rickets, and the adult form is osteomalacia.
- Overproduction of parathyroid hormone: leads to primary hyperparathyroidism, which increases blood calcium and removes calcium from the bone matrix.
- Paget's disease: due to problems with cells responsible for bone remodeling, leading to a weaker bone.
Despite different causes, metabolic bone diseases have similar signs and symptoms. These include bone, joint, or muscle pain and weak bones that are prone to fractures. Some metabolic bone diseases, such as rickets or osteogenesis imperfecta, display delayed development. Osteoporosis and rickets/osteomalacia can also present with some deformities or abnormal posture. All of these are a result of disruption of normal bone homeostasis or equilibrium.
What Are the Risk Factors?
Just like the causes, the risk factors for metabolic bone disease also vary. Factors affecting metabolic bone disease include age, gender, and dietary intake:
- Older age groups are more prone to conditions such as osteoporosis.
- Women are at higher risk of having osteoporosis and primary hyperparathyroidism.
- Men are at higher risk of having Paget’s disease.
- Genetic factors also affect bone disease, especially osteoporosis, Paget's disease, and osteogenesis imperfecta.
- As seen in vitamin D deficiency, an imbalance in diet can lead to the development of bone disorders. People with eating disorders and a strict diet are also predisposed to bone diseases. Vitamin D deficiency can also occur if sunlight exposure is limited.
How is Metabolic Bone Disease Diagnosed?
Metabolic bone disease can be diagnosed through a variety of tests and examinations. This will depend on each patient's history, familial history, clinical manifestations, and signs and symptoms. Radiographs, biopsies, and blood tests can all support the diagnosis of bone disease. In patients with a possible familial history, your doctor may recommend genetic testing.
What Are the Treatment Options?
Treatment of metabolic bone diseases prioritizes the prevention of its further progression, as well as prevention of complications such as fractures. Since most of the conditions are long term and some are hereditary, management of bone disease involves a lot of patient education and lifestyle changes. It is heavily advised to have proper nutrition, supplementation of vitamins, and increased physical activity.
It is best to provide an environment that is safe to reduce slipping or falling occurrences to prevent fractures. This is especially for the older age group and those with familial or hereditary bone diseases. Aside from these precautions, medications can also be given for bone disorders. Medications that prevent bone resorption can help increase bone mineral density. Other disorders such as hyperparathyroidism are treated through surgery, with the removal of the glands responsible.
Metabolic bone disease comprises many other diseases. Despite having different causes and risk factors, their end result and complications are the same, so these diseases also need to be addressed. By preventing fractures and other complications of bone diseases, we improve the quality of life of these patients.