Geroscience: Aging and Oral Health Research.

Research in aging has significantly advanced; scientists are now able to identify interventions that slow the biologic aging processes (i.e., the "hallmarks of aging"), thus delaying the onset and progression of multiple diseases, including oral conditions. Presentations given during the 3-part session "Geroscience: Aging and Oral Health Research," held during the 2023 American Association for Dental, Oral, and Craniofacial Research meeting, are summarized in this publication. Speakers' topics spanned the translational research spectrum. Session 1 provided an overview of the geroscience and health span (disease-free and functional health throughout life) concepts. The common molecular mechanisms between oral cancer and aging were discussed, and research was presented that showed periodontal microflora as a potential factor in Alzheimer's disease progression. Session 2 focused on behavioral and social science aspects of aging and their oral health significance. The keynote provided evidence that loneliness and isolation can have major health effects. These social conditions, along with poor oral health, tooth loss, and cognitive decline, could potentially affect healthy eating ability and systemic health in older adults. Research could help elucidate the directions and pathways connecting these seemingly disparate conditions. Session 3 focused on the delivery of oral care in different settings and the many barriers to access care faced by older adults. Research is needed to identify and implement effective technology and strategies to improve access to dental care, including new delivery and financing mechanisms, workforce models, interprofessional provider education and practice, and use of big data from medical-dental integration of electronic health records. Research to improve the "oral health span," reduce oral health disparities, and increase health equity must be tackled at all levels from biologic pathways to social determinants of health and health policies.

Aging and secretory reserve capacity of major salivary glands.

A loss of acinar cells occurs with aging, while salivary production remains age-stable in healthy adults. It is hypothesized that a secretory reserve exists to preserve function despite a loss of acinar cells in normal aging. The purpose of this double-blind, placebo-controlled, crossover study was to determine age-related differences in salivary response to an anti-sialogogue (glycopyrrolate). Thirty-six healthy subjects (18 young--20-38 yrs; 18 older--60-77 yrs) received 4.0 microg/kg i.v. glycopyrrolate. Parotid and submandibular/sublingual saliva samples and xerostomia questionnaire responses were collected. Variables calculated for each subject were: times to initial and maximum suppression and xerostomic complaint; time to recovery; and durations of suppression and complaint. Salivary function was more adversely affected in older persons. There were no consistent age-associated questionnaire response differences. These findings suggest that salivary gland output is more adversely affected by an anti-sialogogue in healthy older vs. younger adults, supporting the secretory reserve hypothesis of salivary function.

Development of a Visual Analogue Scale questionnaire for subjective assessment of salivary dysfunction.

OBJECTIVE: This study's objective was to develop a Visual Analogue Scale (VAS) xerostomia questionnaire and to evaluate the validity and reliability for the clinical diagnosis of salivary gland dysfunction. STUDY DESIGN: Thirty-six healthy adults participated in this double-blind, crossover study. Each subject received an antisialagogue (glycopyrrolate) or placebo. Unstimulated and stimulated parotid and submandibular saliva samples were collected 16 times over a period of 6 hours. An 8-item VAS xerostomia questionnaire was administered after each saliva collection. RESULTS: The results demonstrated significant reliability for 7 of the 8 VAS items, whereas validity was significant for unstimulated submandibular saliva. Moving averages were calculated for VAS and salivary flow rate values, and significant correlations were observed between these factors, indicating that changes in VAS responses were predictive of changes in salivary flow. CONCLUSIONS: These findings suggest that this VAS xerostomia questionnaire may be helpful in the diagnosis of salivary dysfunction and for detecting changes in salivary flow rate values over time.

Xerostomic complaints induced by an anti-sialogogue in healthy young vs. older adults.

Complaints of xerostomia and salivary hypofunction are common in older adults. However, recent studies reported that dehydration-induced salivary hypofunction caused fewer xerostomic complaints in older compared with young adults. This may predispose older adults to developing oral problems that will subsequently not receive attention from health care providers. Since many medications are known to inhibit salivation, this study attempted to determine if an anticholinergic drug (glycopyrrolate) had a differential effect on xerostomic complaints in young vs. older adults. Eighteen young (age 20-38 yrs) and 18 older (age 60-77 yrs) healthy adults were given a 4.0 micrograms/kg dose of i.v. glycopyrrolate. For 6 hrs after drug administration, stimulated parotid salivary flow was collected, and an eight-item Visual Analogue Scale (VAS) subjective xerostomia test was given. At several time points post-i.v. glycopyrrolate, salivary flow rates were consistently lower in older compared with young adults. For some measures of xerostomic complaint (time to first complaint; time to maximum complaint; mean maximum complaint), there were no age-related differences for all VAS items. However, a trend for increased xerostomic complaints in older adults was demonstrated (time to recovery; total duration of complaint; number xerostomic at 6 hrs). These findings suggest that, given equal doses of an anti-sialogogue, salivary hypofunction is greater in healthy older adults, while increased complaints of xerostomia are not as consistent.

Longitudinal influence of age, menopause, hormone replacement therapy, and other medications on parotid flow rates in healthy women.

BACKGROUND: Recent investigations have demonstrated that parotid salivary dysfunction is not a normal process of aging, but may be the consequence of systemic conditions and their treatment, including medications and menopause. The purpose of this study was to assess longitudinally the influence of age, menopausal status, hormone replacement therapy, and other medications on stimulated parotid flow rates (SPFRs) in healthy women. METHODS: Medical diagnoses, menopausal status, medication utilization, and 2% citric acid stimulated parotid salivas were collected from 396 women, aged 21 to 96 years, from the Baltimore Longitudinal Study of Aging (National Institute on Aging, National Institutes of Health) over a 17-year span by three investigators. RESULTS: There was no overall longitudinal effect of time on SPFR. Age at first visit was a significant predictor of a decrease in SPFR when adjusted for time and xerostomic medications. However, the deleterious effect of taking one xerostomic medication was equivalent to approximately 14 years of aging. Menopausal status and hormone replacement therapy were not consistently associated with diminished SPFR. CONCLUSIONS: These results suggest that menopause and hormone replacement therapy are not associated with parotid salivary dysfunction. Aging may have a statistically significant yet small deleterious influence on SPFR; however, the adverse influence of xerostomic medications is much larger.

Dementia and oral health.

Older adults are the most rapidly growing segment of the population, and the prevalence of dementia in this cohort is increasing as well. Diagnostic and management strategies for dementia are improving. With significantly more dentate older adults, there will be an increased need in the future for dental care services for the geriatric population with dementia. Research reports demonstrate impaired oral health even in community-dwelling adults with moderate dementia. Therefore, oral health care providers will be increasingly challenged with preserving oral and nutritional health in these patients in order to diminish pain and pathology and to maintain the dignity and quality of life of a person with dementia.

Determination of variation of stimulated salivary flow rates.

Salivary hypofunction is associated with oral and pharyngeal disorders and requires early diagnosis and intervention. Large variability in salivary flow rates within and between individuals has been reported, which has impaired the establishment of standard values. The objective of this study was to determine variations in stimulated parotid and submandibular flow rates over 6 hours and to define salivary hypofunction. Pooled mean, standard deviation, and coefficient of variation values for four collection time periods were obtained from 36 healthy males and females (18 young, ages 20-38; 18 older, ages 60-77). The results demonstrated 27-44% variation in salivary flow rates over time. Overall, there were no significant age or gender differences in variability between and within salivary flow rates at all collection time periods. The results suggest that a 45% range in salivary flow rates could be considered normal salivary variation, and values below 45% of normal levels could be used to define salivary hypofunction.

General anesthesia protocol for the dental patient: emphasis for older adults.

As the population ages, with increased retention of the natural dentition, there will be a greater responsibility for dental professionals to maintain the oral health of medically, behaviorally, cognitively, and physically impaired adults. Oral sedatives and nitrous oxide analgesia are frequently and successfully used for dental treatments in these patients. However, many compromised older adults cannot safely tolerate dental treatment with these sedative techniques in an outpatient setting. This paper describes the use of general anesthesia in a hospital environment, coordinated with medical and anesthesia specialists, that is a viable, safe, and effective treatment tool for providing comprehensive dental and oral surgical treatment for the older patient.

Systemic diseases and their treatments in the elderly: impact on oral health.

The lifespan of the US population is increasing, with the elderly desiring successful aging. This goal is jeopardized as multiple systemic conditions and their treatments become more prevalent with age, causing impaired systemic and oral health and influencing an older person's quality of life. To obtain successful aging, a compression of morbidity must be obtained through prevention and management of disease. This paper describes the most common systemic diseases causing morbidity and mortality in persons aged 65+ years: diseases of the heart, malignant neoplasms, cerebrovascular diseases, chronic obstructive pulmonary disease, pneumonia, influenza, diabetes mellitus, trauma, Alzheimer's disease, renal diseases, septicemia, and liver diseases. Disease prevalence and the impact of medications and other therapeutic measures used to treat these conditions are discussed. Oral sequelae are reviewed with guidelines for early detection of these deleterious consequences, considerations for oral treatment, and patient management. An understanding of the impact of systemic diseases and treatment on oral health is imperative for dental practitioners to appropriately treat and manage older patients with these conditions. With a focus on early detection and prevention, oral health care providers can improve the quality of life of this population and aid in the attainment of successful aging.

The influence of hypothyroidism and thyroid replacement therapy on stimulated parotid flow rates.

OBJECTIVE: The purpose of this study was to determine, through use of cross-sectional and longitudinal data, whether hypothyroidism and its treatment with thyroid hormones have a significant effect on the production of stimulated parotid flow rates. STUDY DESIGN: From the Baltimore Longitudinal Study of Aging (NIA, NIH), subjects with hypothyroidism taking and not taking thyroid replacement therapy were evaluated for the production of 2% citrate-stimulated parotid saliva in a cross-sectional and longitudinal investigation. Comparisons were made with nonmedicated healthy control subjects. RESULTS: Cross-sectional analyses revealed that stimulated parotid flow rates were not significantly different between healthy controls, subjects with hypothyroidism on thyroid replacement therapy, and subjects with hypothyroidism not on thyroid replacement therapy. In general, longitudinal analyses revealed no significant differences over time in stimulated parotid flow rates between healthy controls and subjects with hypothyroidism. CONCLUSIONS: Hypothyroidism and the concomitant use of thyroid replacement therapy do not cause significant changes in the production of stimulated parotid saliva.