Nutrition and Oral Medicine (Nutrition and Health)

Chapter 8 / Oral Diseases and Conditions 1371.4. Nutritional Consequences of OralMovement Disorders (e.g., Parkinson’s)Patients with oral movement disorders may be at risk for nutritional consequences.Many oral movement disorders are associated with pathologic alterations in the basalganglia or their neuronal interconnections, although some are less clearly understood.Movement disorders are characterized either by an excess of movement (hyperkinesia ordyskinesia) or by a paucity of movement (hypokinesia or bradykinesia). Different neurologicaldiseases may be characterized clearly by one type of dyskinesia (e.g., ticsassociated with Tourette’s syndrome) or by a combination of overlapping movementdisorders (e.g., dystonia, resting tremor, and bradykinesia associated with Parkinson’sdisease [PD]). In descending order of prevalence, the most common movement disorderis essential tremor, followed by PD, dystonia, and drug-induced dyskinesias.Of the little research carried out in this area, most has focused on PD, a slowlyprogressive and debilitating degenerative disease caused by destruction in the dopaminergicneurons in the substantial nigra of the brain. Patients with PD have muscularrigidity (leading to difficulty in cutting up and moving food into their mouths, andchewing), difficulty swallowing (characterized by increased transit time and impairedtongue coordination), and diminished smell, and eventually they develop dementia.Furthermore, the medications they take, especially levodopa, can lead to xerostomia andGI sequelae such as nausea, vomiting, or constipation. All of these are risk factors formalnutrition, and these patients are often underweight and or malnourished.Damage to the developing central nervous system may result in significant impairmentin oral–motor function and can potentially contribute to feeding difficulty in disabledchildren and result in nutritional impairment. Early recognition, assessment, and treatmentof an infant with neurological impairment that is compromising the normal feedingprocess is crucial. The elderly may be at risk for age-related dimunition of oral–motorfunction (36).1.5. Nutritional Consequences of XerostomiaSalivary hypofunction is estimated to affect approx 5% of the US population (37),primarily the elderly, and has multiple causes including medical problems, medications(including antidepressants, anticholinergics, antispasmodics, antihistamines, antihypertensives,sedatives, and others), head and neck radiotherapy, and Sjögren’s syndrome.Healthy saliva production is essential to the protection of the oral mucosae andteeth and for taste perception, food bolus formation, swallowing, speech, and earlydigestion. Hyposecretion of saliva exemplifies the importance of salivary flow: it causesfood to stick to oral structures and compromises a person’s ability to swallow food;predisposes persons to dental caries, which can result in dental pain and infection;causes hypogeusia or dysgeusia; and puts persons at risk for candidiasis, which cancause mucosal burning. Quality of life and nutritional intake can be affected by xerostomia.Although salivary function remains intact in healthy elderly persons (38), theelderly population has a higher prevalence of the risk factors for xerostomia, and mostof the research linking xerostomia to nutritional consequences is focused on this population,particularly in the institutionalized elderly. Sjögren’s syndrome is an autoimmuneexocrinopathy that is in part characterized by severe salivary hypofunction causedby infiltration of lymphocytes into the salivary gland parenchyma (see Chapter 14).