Nutritional And Dietary Considerations In Fibrodysplasia Ossificans Progressiva

Introduction

Fibrodysplasia Ossificans Progressiva (FOP) is a rare genetic musculoskeletal condition. In this condition muscles and tendons gradually turn into bones which is a process known as ossification. The result of this is the production of an extra bone which inhibits movement completely. The cause of this disease is unknown, however, there are different symptoms including progressive loss of mobility. When there is trauma to a muscle there could be episodes of muscle swelling and inflammation followed by ossification. One characteristic of this condition is malformed big toes which are present at birth.¹

In this condition, the development of bones in areas of the body where bones are not present is referred to as heterotopic ossification. These areas where bones tend to grow in this condition include ligaments, tendons and skeletal muscles. The result of this growth is a metamorphosis of the connective tissues and the body’s skeletal muscles. This leads to progressive locking of the bone joints which consequently makes movement difficult. This abnormal development of bones in soft tissue sites leads to stiffness in the body and hence difficulty in movement which could eventually lead to fusion (ankylosis) of affected joints (neck, back, shoulders, etc.). FOP cases are usually a result of a sporadic new variant in the ACVR1 gene, this occurs in the bone morphogenetic protein (BMP) signalling pathway. This pathway is crucial for the formation of the skeleton within the embryo. It is also important to repair the skeleton after birth.²

For patients with FOP, the importance of nutrition has been highlighted. This is because patients with FOP are at a high risk of nutritional and vitamin deficiencies. Thus, ensuring optimum nutrition and avoiding vitamin deficiencies are a crucial part of countering the nutritional challenges as discussed in more detail throughout the article.³

Nutritional challenges in patients with FOP

There are various nutritional challenges with patients with FOP. These include limited mobility which affects metabolism, difficulty in chewing due to ankylosed jaw and swallowing and various gastrointestinal and digestive issues and poor appetite. Thus, adequate nutrition is extremely important in order to prevent severe weight loss, SMA syndrome and pressure ulcers. Gastrointestinal symptoms have been reported in 28% of patients with FOP. Various symptoms include severe diarrhoea, constipation, digestive disorders and intermittent vomiting.⁴

For patients with FOP, one of the biggest challenges is limited mobility which has an impact on metabolism. As FOP progresses, mobility becomes further restricted. In this condition, immobilisation of the limbs, jaw and chest wall, results in severe disability. FOP a condition of ectopic skeletogenesis which is particularly disabling. A lot of patients with FOP could need a wheelchair by the third decade of their life.⁵ 

Especially, for patients with an ankylosed jaw, it is essential to consult a nutritionist, and for extenuating situations, patients would need a feeding tube. This is due to the difficulties in chewing due to ankylosed jaws for patients with FOP. Furthermore, patients with FOP also have various deficiencies which include vitamin D deficiency. Calcium intake could be suboptimal as it is believed that it could worsen heterotopic ossification even though this is a widely believed misconception.³

Dietary recommendations for FOP and supplementation strategies

Adequate nutrition is important in patients with FOP in order to help prevent issues like severe weight loss, Superior Mesenteric Artery (SMA) and pressure ulcers. Monitoring unintentional weight loss is essential to prevent any complications in the future.⁶ Natalie Ledesma provided a cohesive breakdown of the nutritional needs and recommendations for patients with FOP. A healthy eating plate should consist of plenty of fruits and vegetables.⁷ It is recommended to eat a variety of whole grains like whole wheat bread and limit refined grains like white rice and white bread. Additionally, it is recommended to intake fish, poultry, beans and nuts whilst limiting red meat, cheese, cold cuts and processed meats.  

According to recent guidelines, for dietary recommendations, it is explained that there are various macronutrient needs for patients with FOP which include adequate protein intake which is essential for muscle maintenance. This is particularly important as atrophy could be experienced by patients with FOP. Furthermore, carbohydrates and fats,  especially omega-3 are essential to reduce inflammation due to their anti-inflammatory properties.  

For the micronutrient requirements, calcium has been considered to be suboptimal which is a result of the misconception that it could worsen heterotopic ossification. Furthermore, magnesium and zinc could also be useful.⁸

Special nutritional considerations

In addition to this, a balanced diet is seen as being crucial which includes anti-inflammatory foods which have anti-oxidants as well as anti-inflammatory properties like fruits, vegetables and omega-3 fatty acids. These types of foods help to reduce inflammation. Hydration is also considered particularly important for patients with FOP as dehydration occurs quite commonly.⁸

As explained by Natalie Ledesma in her webinar, the inflammation in the GI tract occurs as a result of a leaky gut which occurs when the gut is permeable for food particles to pass through the barrier. The immune system attacks these particles leading to food allergies and other chronic health problems. This systemic inflammation could lead to even more depressive symptoms related to obesity. A healthy mucosa in the gut allows nutrients to pass the barrier and does not allow the toxins to enter. However, in an injured gut, the injured mucosa blocks nutrients at the damaged villi and allows toxins into the bloodstream. Hence, it is seen as crucial to improve the gut microbiome health. This is important for patients with FOP due to the various gastrointestinal issues faced by them. The different points of consideration include:

• High fluid consumption to prevent dehydration
• Eating regular meals of moderate volume 
• Exercising 
• Managing stress

Nutritional considerations and a healthy diet are seen as crucial in helping patients with FOP manage their symptoms and enter a line of recovery. The rebalancing of the GI tract through these lifestyle modifications can help patients with FOP manage their symptoms and improve their overall wellness.⁷

Meal planning and preparation tips

For patients with FOP, it is important to measure the caloric intake in order to avoid unintentional weight loss or gain. Obesity has been seen as a risk factor for increased mortality and thus, strategies to maintain a healthy weight have been seen as being crucial for patients with chronic conditions such as FOP. The strategies to maintain a healthy weight for patients in FOP include treating obesity as a chronic condition especially as it is vastly underdiagnosed, eliminating the stigma surrounding obesity as well as incorporating dedicated time and workflows and aiming at doing so that primary care providers address a variety of issues during patient visits.⁹

For patients with FOP, a soft diet can be considered. Soft diets are beneficial for people with an illness or after surgery. This involved having tender and easily digestible food. For patients with swallowing disorders, soft diets are particularly useful and hence, for patients with FOP. Some examples of soft diets which are nutrient-dense are smoothies, purees and well-cooked vegetables.¹⁰

Managing gastrointestinal issues & Multidisciplinary care 

Patients with FOP experience a range of gastrointestinal issues which include frequent nausea and vomiting with constipation being a common issue.⁵ Fibre intake is seen as essential for[patients with FOP a low fibre diet along with other factors like deficient water intake and excess animal protein intake increases the risk of developing kidney stones.¹¹         

Furthermore, the role of probiotics is seen as essential for patients with FOP as they are used to reduce gastrointestinal symptoms such as gas, bloating and constipation. Along with probiotic supplements, there are various foods which are rich in probiotics including yoghurt and fermented vegetables like pickles.¹² Furthermore, a high fibre intake would ensure that there is bowel regularity further reducing gastrointestinal symptoms. 

Thus, the role of a multidisciplinary team is essential for patients with FOP which includes involving dietitians, physicians and healthcare professionals to help cater to the overall wellness of the patient. Furthermore, specifically tailoring nutrition plans for patients and monitoring their health, mobility and symptoms. Thus, regular monitoring would help healthcare providers monitor symptoms and prevent any complications from arising. 

Case studies and real-life examples

There were 4 cases which were reported. One of them was of a 10-year-old male who had experienced limited shoulder range of movement and truncal swelling over a period of a year. He had completed all his vaccinations and did not have a history of past illnesses. His symptoms had been progressing but there was no family history of such a condition. He had an average height was of average weight and did not have any dysmorphic features. When examined, there were non-tender solid lobules on the back over the upper trunk region. The shoulder's active and passive movement was limited and the patient had bilateral deformed short and big toes. FOP diagnosis was made for this patient on clinical diagnosis with X-rays and CT scans confirming the diagnosis.¹³ 

A case study was conducted for an 18-year-old boy with Fibrodysplasia Ossificans who lost weight at an accelerated rate as a result of gastrointestinal symptoms. He lost 36 kgs in the span of a year. The patient had biliary vomiting while being hospitalised and his CT was reexamined. He was diagnosed with superior mesenteric artery syndrome. Through this study, it was concluded that in weight loss cases it is important for clinicians to consider superior mesenteric artery syndrome.²

Conclusion 

Throughout this article, the concept of nutrition and its importance in helping patients with FOP improve and treat their symptoms was explored. The link with the GI tract with different chronic conditions provides an insight into the role of nutrition on the body and hence, the dietary considerations on the improvement of FOP symptoms. 

Special dietary considerations and planning could significantly help improve symptoms such as gastrointestinal symptoms improving the lives of patients with FOP as well as help prevent any further complications.

Further research could potentially involve researching specific nutrients and their effects on the improvement of FOP. This could further help nutritionists and dieticians tailor strategies for patients with FOP.