Falls can be difficult for people with Parkinson's disease (PD), leading to fractures and other injuries. People with PD are at increased risk of fracture, with a four times higher risk of hip fracture than the general population. A person with PD will often return to their baseline after recovery from a fracture. However, for some, a fracture and its resultant immobility and the effects of a potential surgery and hospitalization will lead to a permanent decline in their condition. Therefore, steps to prevent falls are a crucial goal of PD management.

But not every fall can be prevented, so an often-overlooked part of managing someone who tends to fall is assessing bone density and treating low bone density if possible. A fall that could result in a fracture in someone with low bone density could be much less of a problem in someone with average bone density.

Bone density is assessed using a simple test called dual-energy X-ray absorptiometry (DEXA), also known as bone densitometry. X-ray technology is used to measure the thickness of the hip and spine bones. Depending on the bones' mineralization level, the test can diagnose osteoporosis, "porous bones."

People with PD need to have their bone mineral density assessed because they are at increased risk of falls and because studies show that people with PD have lower bone mineral density than age-matched controls.

There are several research to suggest why people with PD have bones that are less dense than the general population:

• Studies were done in cell culture, and animals show that dopamine receptors are expressed in bone cells and influence bone strength. A decrease in dopamine signaling in PD may decrease bone strength.
• Levodopa treatment for PD may reduce the rate of bone formation.
• In PD, Lewy bodies can be found in the hypothalamus, the area of the brain responsible for secreting the hormones that regulate bone density.

In addition, low bone density can be a direct consequence of PD symptoms. A person with PD may:

• Perform less weight-bearing activity
• Have less exposure to the sun and experience increased levels of malnutrition, both of which can lead to lower Vitamin D levels and weaker bones?
• Experience weight loss which is associated with weaker bones

Weak bone density can be successfully treated – including in people with PD.

• Exercise & Bone Health
  Weight-bearing activities and exercise are vital in maintaining bone strength. This adds yet another reason why training is so essential in PD management. (To learn more about getting started with exercise, check out our free Be Active & Beyond exercise guide, which is also available in Spanish.) Consider joining an exercise class or enlisting the help of a physical therapist or personal trainer – but look for specialized ones for people with PD to ensure that they are safe and appropriate. There are many exercise classes you can join virtually from home.
• Medications for Bone Health
  There are also many available medications for osteoporosis to improve bone mineralization and decrease fracture risk. For these reasons, bone density needs to be tested to initiate treatment if necessary. Based on your test results, your doctor may talk to you about medication options (in addition to exercise) to increase your bone mineralization.

Besides the apparent importance of Vitamin D in maintaining bone health in people with PD, there have also been numerous studies investigating other associations between Vitamin D and PD. There are conflicting results as to whether low levels of Vitamin D are associated with an increased risk of developing PD. In addition, some studies demonstrate an increased rate of Vitamin D deficiency in people with PD compared to age-matched controls and even link low Vitamin D levels to increased severity of PD symptoms. Conclusion: there are conflicting results as to whether Vitamin D supplementation can reduce PD symptoms. More studies are necessary to clarify these associations.

Vitamin D is a critical nutrient derived from two sources – your diet and exposure to sunlight. Not many foods contain Vitamin D, so about 70-80% of our Vitamin D needs to be obtained from sunlight (Ultraviolet B from sunlight converts a steroid precursor in the skin to Vitamin D.) Vitamin D plays many roles in the body, including helping with calcium absorption from food and supporting the mineralization of bone. (To get some Vitamin D from your diet, try salmon, canned tuna, and mushrooms that naturally contain Vitamin D. There are also many kinds of milk, yogurt, and orange juice options fortified with Vitamin D.)

Because people tend to spend a lot of time inside, especially in the winter, Vitamin D deficiency is a widespread problem in the general population. Vitamin D deficiency can be more pronounced for those with PD, who might have an even harder time getting outside.

Vitamin D levels can be tested in blood. If it is low, over-the-counter supplements are readily available.

Despite optimizing fall prevention and bone strength, people with PD may still experience fractures. The hip is a common site of injury which typically requires surgical intervention. It is reassuring to note that should this be necessary, immediate post-op complications of hip fracture surgery are the same in people with PD compared to age-matched controls.

However, more long-standing complications after hip fracture do occur in people with PD, including:

• Increased immobility, morbidity, and mortality at one year
• Increased discharge to a rehab facility or long-term care institution

Prevention of falls and fractures should be a priority for people with PD.

• Falls and resultant fractures are common in people with PD.
• Although fall prevention in PD is vital, ensuring solid bones is another way to prevent fractures
• There are relatively easy ways to improve your bone density and decrease your risk of fractures
• Talk with your doctor about having your bone density checked via a DEXA scan and get treated if it shows that you have the low bone density
• In addition, discuss the concerns with your doctor about having your Vitamin D levels checked and take supplementation if warranted
• Consider joining the TOPAZ clinical trial, which is investigating fracture prevention in people with PD