Parkinson's Disease & Low Sodium

Parkinson’s disease, or PD, is a motor system disorder; it affects your coordination and ability to move. The diagnosis is based entirely on symptoms, as there is no diagnostic test for PD. Hyponatremia or low sodium is a condition that results from medication side effects, excess sodium excretion, excessive fluid intake or disease processes. There is a connection between PD and hyponatremia; PD does not cause hyponatremia, but medications and some of the complications of the disease can be a factor.

Parkinson's Disease

Parkinson’s disease is caused by the loss of cells in the brain that produce a neurotransmitter called dopamine. Symptoms include tremor or trembling of the limbs, head and face; slow movements; rigidity of the limbs and trunk and impaired coordination, including impaired balance. The disease is usually seen in people over the age of 50, and tends to worsen with age. It is a chronic disease and there is no cure.

Sodium and Hyponatremia

Sodium is one of the most important minerals in the body. An electrolyte, sodium helps regulate the water in your body and inside your cells. When you have hyponatremia, you have too little sodium compared to the amount of water. The low sodium causes cells to begin swelling, which can cause problems ranging from mild to life-threatening. People with hyponatremia may have fatigue, headache, nausea, muscle spasms or even seizures. Some medications can cause hyponatremia, either as a side effect or if the drug is stopped suddenly.

Medications

Depression is a common psychiatric symptom in PD patients, and some antidepression medications can cause hyponatremia. Changes in PD medications can also cause problems. In one case reported in the April 1996 “Progress in Neuropsychopharmacology and Biological Psychiatry,” when the medications for PD were suddenly stopped, the patient developed acute hyponatremia.

Age and Hyponatremia

Elderly people are at higher risk for hyponatremia, and PD is a disease of older people. As you age, a number of the body systems that manage your fluid balance, such as responsiveness to thirst, may degrade. According to Dr. Myron Miller, geriatricians –- doctors who specialize in caring for the elderly -– know that hyponatremia is common in this age group. Miller reports that in a group of people over 65 who still lived in their own homes and did not have acute illness, 7 percent were hyponatremic.

Diet and Fluid Intake

People who have PD may develop alterations in taste or smell, nausea or difficulty swallowing. PD may also cause dementia, and some of the medications can induce hallucinations. All of these conditions can make it more difficult for the individual or the caregiver to ensure adequate fluid intake and a healthy diet. Low blood pressure is a common symptom of PD and the patient may be on a high sodium diet, which can induce thirst. Excessive water intake can result in hyponatremia.

Parkinson's Disease & Low Sodium