Oral health in patients with type II diabetes and impaired glucose tolerance.

OBJECTIVE: To assess the influence of type II diabetes and impaired glucose tolerance on dental, periodontal, and oral mucosal tissues. RESEARCH DESIGN AND METHODS: We examined 11 subjects with type II diabetes, 32 with impaired glucose tolerance, and 43 control subjects from the oral physiology component of the Baltimore Longitudinal Study of Aging. At the time of the study, none of the participants was taking medication nor being treated for any medical problems other than diabetes. RESULTS: Only a few statistically significant dental and periodontal changes were apparent in the group with type II diabetes, and no oral mucosal differences existed between the diabetes and control groups. Dental, periodontal, and oral mucosal parameters in patients with impaired glucose tolerance were essentially indistinguishable from the other two groups. CONCLUSIONS: These findings suggest that among well-controlled individuals with type II diabetes and impaired glucose tolerance, few appreciable differences are evident in oral health.

Treatment of primary Sjögren's syndrome with low-dose natural human interferon-alpha administered by the oral mucosal route: a phase II clinical trial. IFN Protocol Study Group.

The purpose of this investigation was to examine the safety and efficacy of four dosages of natural human interferon-alpha (nHuIFN-alpha) delivered over a 12-week period orally in lozenges (150 IU and 450 IU, once [QD] or three times [TID] daily) compared to placebo in subjects with primary Sjögren's syndrome. This randomized, double-blinded clinical trial demonstrated that nHuIFN-alpha at a dose of 150 IU administered TID by oral lozenge significantly improved stimulated whole saliva output compared to placebo after 12 weeks of treatment. The 150 IU TID dose also was suggestive of benefit for 5 of 7 subjective measures of oral and ocular comfort. IFN lozenges demonstrated a good safety profile, with no serious adverse events found in any treatment group. There were no significant differences between the placebo and the four doses of IFN for adverse events by total number, organ system, severity, dropouts, and number judged to be related to treatment. In conclusion, these results demonstrated that the use of 150 IU IFN lozenges TID for 12 weeks in subjects with primary Sjögren's syndrome improved salivary output and decreased complaints of xerostomia without causing significant adverse medical events.

Epidemiology of acquired immune deficiency syndrome in persons aged 50 years or older.

Acquired immune deficiency syndrome (AIDS) has afflicted persons of all ages, yet only recently has attention been devoted to AIDS in older persons. To examine the epidemiology of AIDS in persons greater than or equal to 50 years old in the United States, we analyzed cases reported to the Centers for Disease Control. The number reported annually in persons greater than or equal to 50 years old increased from 13 in 1981 to 3,562 in 1989. Through December 1989, 11,984 had been reported, representing 10% of all cases. Although male homosexual contact accounted for most cases in persons aged 50-69, blood transfusion became a more common means of exposure with increasing age, accounting for 28% of cases in persons aged 60-69 and 64% of cases in individuals aged greater than or equal to 70. The proportion of women increased from 6.1% in persons with AIDS aged 50-59 to 28.7% of those aged greater than or equal to 70. The proportion of AIDS diagnoses made in the same month as death increased from 16% in persons aged 50-59 to 37% in those aged greater than or equal to 80, suggesting either more rapid progression of disease or increasing delay in diagnosis. As the incidence in older persons continues to increase, clinicians caring for older patients must become more familiar with AIDS.

Oral defense mechanisms are impaired early in HIV-1 infected patients.

We have examined the hypothesis that individuals infected with human immune deficiency virus type 1 (HIV-1) experience significant, specific alterations in mechanisms protecting the oral cavity prior to the appearance of AIDS-related systemic opportunistic infections. In a study of 13 early-stage, stable anti-HIV antibody positive patients, parotid salivary function was found to be generally intact. In contrast, several indicators of submandibular gland dysfunction were detected. In particular, stimulated fluid output was decreased and salivary lysozyme levels were increased relative to controls by 50-60% for both resting (p less than 0.05) and stimulated (p less than 0.001) conditions. Also, the frequency of albumin detection in submandibular saliva samples was approximately 65% in HIV-1 infected patients vs. 0% in controls (p less than 0.05). In addition, cytologic evaluation of oral mucosa revealed a fivefold increase in the prevalence of candidal hyphae in HIV-1 infected patients compared to controls (41% vs. 8%, p less than 0.05). We conclude that normal oral defense mechanisms show signs of compromise in HIV-1 infected individuals. We suggest that (a) effects of HIV-1 infection are seen early in the oral cavity, (b) impairment of oral defense mechanisms may facilitate entry of microorganisms with an attendant increased risk of morbidity and mortality, and (c) intensive oral surveillance and prophylactic care should be part of the routine management afforded to AIDS patients soon after HIV-1 infection is recognized.

Partial irradiation of the parotid gland.

Recent efforts to reduce xerostomia associated with irradiation (RT) of head and neck cancer include the use of conformal and intensity-modulated RT (IMRT) to partly spare the major salivary glands, notably the parotid glands, from a high radiation dose while treating adequately all the targets at risk of disease. Knowledge of the dose-volume-response relationships in the salivary glands would determine treatment planning goals and facilitate optimization of the RT plans. Recent prospective studies of salivary flows following inhomogeneous irradiation of the parotid glands have utilized dose-volume histograms (DVHs) and various models to assess these relationships. These studies found that the mean dose to the gland is correlated with the reduction of the salivary output. This is consistent with a pure parallel architecture of the functional subunits (FSUs) of the salivary glands. The range of the mean doses, which have been found in these studies to cause significant salivary flow reduction is 26 to 39 Gy.

Major salivary gland function in patients with radiation-induced xerostomia: flow rates and sialochemistry.

Radiation therapy for cancer of the head and neck region often causes salivary gland dysfunction and xerostomia. Several reports suggest that the submandibular/sublingual (SM/SL) glands may be less radiosensitive than the parotid. The purpose of this study was to evaluate differential radiation effects on the major salivary glands. Fifty patients with radiation-induced xerostomia were evaluated (33 males, 17 females; mean age 52.7). The average total tumor dose was 6034 cGy. Major salivary gland function was compared with that of 50 non-irradiated controls. Salivary flow rates included unstimulated and stimulated flows of both the parotid and SM/SL glands. Sialochemical analyses included total protein, lysozyme, lactoferrin, sodium, chloride, and potassium. All four measures of salivary flow were significantly reduced in patients as compared to controls (p = .0001). Like the parotid, submandibular/sublingual gland dysfunction appears to be radiation dose- and field-dependent. Patients in the lowest radiation dose quartile (< or = 5000 cGy) had significantly increased salivary flow compared to those in the highest dose quartile (> or = 6800 cGy; p = .025). Glands that were partially irradiated were more likely to have some residual function than fully irradiated glands (p = .003). Lactoferrin content was increased in parotid saliva of radiation patients (p = .0001). Chloride content was significantly increased also (p = .0001). The SM/SL glands are clearly dysfunctional in post-irradiation xerostomia patients compared to controls, in terms of both flow rates and sialochemistry.

Dose, volume, and function relationships in parotid salivary glands following conformal and intensity-modulated irradiation of head and neck cancer.

PURPOSE: To determine the relationships between the three-dimensional dose distributions in parotid glands and their saliva production, and to find the doses and irradiated volumes that permit preservation of the salivary flow following irradiation (RT). METHODS AND MATERIALS: Eighty-eight patients with head and neck cancer irradiated with parotid-sparing conformal and multisegmental intensity modulation techniques between March 1994 and August 1997 participated in the study. The mean dose and the partial volumes receiving specified doses were determined for each gland from dose-volume histograms (DVHs). Nonstimulated and stimulated saliva flow rates were selectively measured from each parotid gland before RT and at 1, 3, 6, and 12 months after the completion of RT. The data were fit using a generalized linear model and the normal tissue complication probability (NTCP) model of Lyman-Kutcher. In the latter model, a "severe complication" was defined as salivary flow rate reduced to < or =25% pre-RT flow at 12 months. RESULTS: Saliva flow rates data were available for 152 parotid glands. Glands receiving a mean dose below or equal to a threshold (24 Gy for the unstimulated and 26 Gy for the stimulated saliva) showed substantial preservation of the flow rates following RT and continued to improve over time (to median 76% and 114% of pre-RT for the unstimulated and stimulated flow rates, respectively, at 12 months). In contrast, most glands receiving a mean dose higher than the threshold produced little saliva with no recovery over time. The output was not found to decrease as mean dose increased, as long as the threshold dose was not reached. Similarly, partial volume thresholds were found: 67%, 45%, and 24% gland volumes receiving more than 15 Gy, 30 Gy, and 45 Gy, respectively. The partial volume thresholds correlated highly with the mean dose and did not add significantly to a model predicting the saliva flow rate from the mean dose and the time since RT. The NTCP model parameters were found to be TD50 (the tolerance dose for 50% complications rate for whole organ irradiated uniformly) = 28.4 Gy, n (volume dependence parameter) = 1, and m (the slope of the dose/response relationship) = 0.18. Clinical factors including age, gender, pre-RT surgery, chemotherapy, and certain medical conditions were not found to be significantly associated with the salivary flow rates. Medications (diuretics, antidepressants, and narcotics) were found to adversely affect the unstimulated but not the stimulated flow rates. CONCLUSIONS: Dose/volume/function relationships in the parotid glands are characterized by dose and volume thresholds, steep dose/response relationships when the thresholds are reached, and a maximal volume dependence parameter in the NTCP model. A parotid gland mean dose of < or =26 Gy should be a planning goal if substantial sparing of the gland function is desired.

Xerostomia and its predictors following parotid-sparing irradiation of head-and-neck cancer.

PURPOSE: To assess long-term xerostomia in patients receiving parotid-sparing radiation therapy (RT) for head-and-neck cancer, and to find the patient and therapy-related factors that affect its severity. PATIENTS AND METHODS: From March 1994 through January 2000, 84 patients received comprehensive bilateral neck RT using conformal and multisegmental intensity-modulated RT (IMRT) aiming to spare the major salivary glands. Before RT and periodically through 2 years after the completion of RT, salivary flow rates from each of the major salivary glands were selectively measured. At the same time intervals, each patient completed an 8-item self-reported xerostomia-specific questionnaire (XQ). To gain a relative measure of the effect of RT on the minor salivary glands, whose output could not be measured, the surfaces of the oral cavity (extending to include the surface of the base of tongue) were outlined in the planning CT scans. The mean doses to the new organ ("oral cavity") were recorded. Forty-eight patients receiving unilateral neck RT were similarly studied and served as a benchmark for comparison. Factors predicting the XQ scores were analyzed using a random-effects model. RESULTS: The XQ was found to be reliable and valid in measuring patient-reported xerostomia. The spared salivary glands which had received moderate doses in the bilateral RT group recovered to their baseline salivary flow rates during the second year after RT, and the spared glands in the unilateral RT group, which had received very low doses, demonstrated increased salivary production beyond their pre-RT levels. The increase in the salivary flow rates during the second year after RT paralleled an improvement in xerostomia in both patient groups. The improvement in xerostomia was faster in the unilateral compared with the bilateral RT group, but the difference narrowed at 2 years. The major salivary gland flow rates had only a weak correlation with the xerostomia scores. Factors found to be independently associated with the xerostomia scores were the pre-RT baseline scores, the time since RT, and the mean doses to the major salivary glands (notably to the submandibular glands) and to the oral cavity. CONCLUSION: An improvement over time in xerostomia, occurring in tandem with rising salivary production from the spared major salivary glands, suggests a long-term clinical benefit from their sparing. The oral cavity mean dose, representing RT effect on the minor salivary glands, was found to be a significant, independent predictor of xerostomia. Thus, in addition to the major salivary glands, sparing the uninvolved oral cavity should be considered as a planning objective to further reduce xerostomia.

Patterns of local-regional recurrence following parotid-sparing conformal and segmental intensity-modulated radiotherapy for head and neck cancer.

PURPOSE: To analyze the patterns of local-regional recurrence in patients with head and neck cancer treated with parotid-sparing conformal and segmental intensity-modulated radiotherapy (IMRT). METHODS AND MATERIALS: Fifty-eight patients with head and neck cancer were treated with bilateral neck radiation (RT) using conformal or segmental IMRT techniques, while sparing a substantial portion of one parotid gland. The targets for CT-based RT planning included the gross tumor volume (GTV) (primary tumor and lymph node metastases) and the clinical target volume (CTV) (postoperative tumor bed, expansions of the GTVs and lymph node groups at risk of subclinical disease). Lymph node targets at risk of subclinical disease included the bilateral jugulodigastric and lower jugular lymph nodes, bilateral retropharyngeal lymph nodes at risk, and high jugular nodes at the base of skull in the side of the neck at highest risk (containing clinical neck metastases and/or ipsilateral to the primary tumor). The CTVs were expanded by 5 mm to yield planning target volumes (PTVs). Planning goals included coverage of all PTVs (with a minimum of 95% of the prescribed dose) and sparing of a substantial portion of the parotid gland in the side of the neck at less risk. The median RT doses to the gross tumor, the operative bed, and the subclinical disease PTVs were 70.4 Gy, 61.2 Gy, and 50.4 Gy respectively. All recurrences were defined on CT scans obtained at the time of recurrence, transferred to the pretreatment CT dataset used for RT planning, and analyzed using dose-volume histograms. The recurrences were classified as 1) "in-field," in which 95% or more of the recurrence volume (V(recur)) was within the 95% isodose; 2) "marginal," in which 20% to 95% of V(recur) was within the 95% isodose; or 3) "outside," in which less than 20% of V(recur) was within the 95% isodose. RESULTS: With a median follow-up of 27 months (range 6 to 60 months), 10 regional recurrences, 5 local recurrences (including one noninvasive recurrence) and 1 stomal recurrence were seen in 12 patients, for a 2-year actuarial local-regional control rate of 79% (95% confidence interval 68-90%). Ten patients (80%) relapsed in-field (in areas of previous gross tumor in nine patients), and two patients developed marginal recurrences in the side of the neck at highest risk (one in the high retropharyngeal nodes/base of skull and one in the submandibular nodes). Four regional recurrences extended superior to the jugulodigastric node, in the high jugular and retropharyngeal nodes near the base of skull of the side of the neck at highest risk. Three of these were in-field, in areas that had received the dose intended for subclinical disease. No recurrences were seen in the nodes superior to the jugulodigastric nodes in the side of the neck at less risk, where RT was partially spared. CONCLUSIONS: The majority of local-regional recurrences after conformal and segmental IMRT were "in-field," in areas judged to be at high risk at the time of RT planning, including the GTV, the operative bed, and the first echelon nodes. These findings motivate studies of dose escalation to the highest risk regions.

Comprehensive irradiation of head and neck cancer using conformal multisegmental fields: assessment of target coverage and noninvolved tissue sparing.

PURPOSE: Conformal treatment using static multisegmental intensity modulation was developed for patients requiring comprehensive irradiation for head and neck cancer. The major aim is sparing major salivary gland function while adequately treating the targets. To assess the adequacy of the conformal plans regarding target coverage and dose homogeneity, they were compared with standard irradiation plans. METHODS AND MATERIALS: Fifteen patients with stage III/IV head and neck cancer requiring comprehensive, bilateral neck irradiation participated in this study. CT-based treatment plans included five to six nonopposed fields, each having two to four in-field segments. Fields and segments were devised using beam's eye views of the planning target volumes (PTVs), noninvolved organs, and isodose surfaces, to achieve homogeneous dose distribution that encompassed the targets and spared major salivary gland tissue. For comparison, standard three-field radiation plans were devised retrospectively for each patient, with the same CT-derived targets used for the clinical (conformal) plans. Saliva flow rates from each major salivary gland were measured before and periodically after treatment. RESULTS: On average, the minimal dose to the primary PTVs in the conformal plans [95.2% of the prescribed dose, standard deviation (SD) 4%] was higher than in the standard plans (91%, SD 7%; p = 0.02), and target volumes receiving <95% or <90% of the prescribed dose were smaller in the conformal plans (p = 0.004 and 0.02, respectively). Similar advantages of the conformal plans compared to standard plans were found in ipsilateral jugular nodes PTV coverage. The reason for underdosing in the standard treatment plans was primarily failure of electron beams to fully encompass targets. No significant differences were found in contralateral jugular or posterior neck nodes coverage. The minimal dose to the retropharyngeal nodes was higher in the standard plans. However, all conformal plans achieved the planning goal of delivering 50 Gy to these nodes. In the conformal plans, the magnitude and volumes of high doses in noninvolved tissue were significantly reduced. The main reasons for hot spots in the standard plans (whose dose calculations included missing tissue compensators) were photon/electron match line inhomogeneities, which were avoided in the conformal plans. The mean doses to all the major salivary glands, notably the contralateral parotid (receiving on average 32% of the prescribed dose, SD 7%) were significantly lower in the conformal plans compared with standard radiation plans. The mean dose to the noninvolved oral cavity tended to be lower in the conformal plans (p = 0.07). One to 3 months after radiation, on average 60% (SD 49%) of the preradiation saliva flow rate was retained in the contralateral parotid glands and 10% (SD 16%) was retained in the submandibular/sublingual glands. CONCLUSIONS: Planning and delivery of comprehensive irradiation for head and neck cancer using static, multisegmental intensity modulation are feasible. Target coverage has not been compromised and dose distributions in noninvolved tissue are favorable compared with standard radiation. Substantial major salivary gland function can be retained.

Parotid gland sparing in patients undergoing bilateral head and neck irradiation: techniques and early results.

PURPOSE: To minimize xerostomia in patients receiving bilateral head and neck irradiation (RT) by using conformal RT planning to spare a significant volume of one parotid gland from radiation. METHODS AND MATERIALS: The study involved 15 patients with head and neck tumors in whom bilateral neck radiation was indicated. The major salivary glands and the targets (tumor, surgical bed, metastases to lymph nodes, and the locations of lymph nodes at risk for metastases) were outlined on axial computed tomography images. Beam's-eye view (BEV) displays were used to construct conformal beams that delivered the prescribed doses to the targets while sparing from direct radiation most of one parotid gland. The gland that was planned to be spared resided in the neck side that was judged in each patient to be at a lesser risk of metastatic disease. Major salivary gland flow rates and the responses to a subjective xerostomia questionnaire were assessed before, during, and after radiation. RESULTS: Radiation planning for patients with central oropharyngeal tumors required the generation of multiple axial nonopposed beams. The resulting isodoses encompassed the targets, including the retropharyngeal nodes and the jugular nodes up to the base of skull bilaterally, while limiting the dose to the oral cavity, spinal cord, and one parotid gland. For patients with lateralized tumors, the ipsilateral neck side was treated up to the base of the skull; in the contralateral neck side, the treatment included the subdigastric nodes but excluded the jugular nodes at the base of the skull and most of the parotid gland. This was accomplished by a moderate gantry angle that was chosen using the BEV displays. Three months following the completion of radiation, the spared parotid glands retained on average 50% of their unstimulated and stimulated flows. In contrast, no saliva flow was measured from the unspared glands in any of the patients. Subjective xerostomia was absent, mild, or not different from that reported before radiation in 10 of 15 patients (67%). CONCLUSION: Partial parotid gland sparing is feasible by using three-dimensional planning in patients undergoing bilateral head and neck radiation. Approximately 50% of the saliva flow from the spared glands may be retained, and most patients thus treated have no or mild xerostomia in the early period after the completion of radiation. Whether tumor control and late complications are comparable to standard radiation will be assessed as more experience is gained.

Longitudinal study on oral health in subjects with Alzheimer's disease.

OBJECTIVE: To examine longitudinal oral health changes in unmedicated, generally healthy subjects with Alzheimer's disease (AD) and compare them to age- and gender-matched healthy, unmedicated control subjects. DESIGN: Oral health parameters were evaluated over 2 to 3 years and the results compared between subjects with AD and controls. SETTING: Clinical Center of the National Institutes of Health, Bethesda, Maryland. PARTICIPANTS: Twenty-one community-dwelling subjects with a clinical diagnosis of AD and 21 age- and gender-matched control subjects. Neither population was being treated for any other systemic condition nor taking any prescription medications. MEASUREMENTS: Unstimulated and stimulated major salivary gland flow rates were measured, and gingival, periodontal, dental, and oral mucosal tissues assessed. MAIN RESULTS: In general, subjects with AD demonstrated decreased salivary flow rates and diminished oral health, but most longitudinal changes in oral health status were not significantly different than controls. CONCLUSIONS: Patients with AD are susceptible to a variety of oral health problems, and progression of AD can lead to a deterioration in oral health and function. These patients require aggressive preventive care to maintain function for as long as possible, which necessitates close cooperation among numerous health care professionals.

The importance of oral health in the older patient.

Oral health is important to general health because stomatologic disease affects more than the mouth. Increasing preservation of teeth among present and future cohorts of older people has increased their risk for serious disease from oral pathogens. The intent of this paper is twofold: first, to alert non-dental health personnel to the significance of oral health and oral disease in the older adult; and second, to recruit the assistance of non-dental professionals in helping patients to achieve and maintain an optimal oral condition. Normative aging processes alone have little effect on the oral cavity, but common disease processes affecting oral health include tooth loss, dental caries, periodontal diseases, and oral mucosal diseases (including candidiasis and squamous cell carcinoma). Systemic diseases and their treatments frequently affect salivary, oral motor, and oral sensory functions. As a result of bacteremia or aspiration of oral contents, organisms of oral origin can be responsible for serious nonstomatological infections. Clinicians caring for older people need to recognize the importance of stomatological health, include an oral component in the multidisciplinary geriatric assessment, support the education of patients on aspects of dental health, and advocate the expansion of personal and public oral health benefits for older adults.

Geriatric oral health and its impact on eating.

OBJECTIVE: Adequate food and fluid intake and nutritional health are requisites for sustaining life. The oral-pharyngeal region has evolved multiple, highly regulated processes to ensure that the intake, chewing, and swallowing of foods and beverages is maintained. The objective of this paper is to identify the independent and collective roles of oral health on eating in older people. DESIGN: Research reports from peer-reviewed scientific journals. Hypothesis-driven research that objectively examined taste, smell, dental and oral mucosal health, dental prostheses, chewing, and swallowing in the context of aging. DATA EXTRACTION AND SYNTHESIS: Data results were extracted independently by multiple observers. A qualitative synthesis of data results from independent studies was made in order to form conclusions regarding the role of oral health on eating in older people. CONCLUSIONS: Many oral functions remain intact in healthy older adults. However, significant alterations arise from oral and systemic diseases and their treatments, and these may have a profound effect on eating, drinking, and the nutritional status of older individuals. The care of older persons with smell, taste, dental/alveolar, oral mucosal, chewing, and swallowing problems requires a multidisciplinary team of health care providers. Recognition of the interrelationship between oral, pharyngeal, and systemic physiological processes will help practitioners identify the etiology of these disorders and implement appropriate therapy.

Tongue strength and endurance in different aged individuals.

BACKGROUND: It is generally accepted that age-related changes occur in voluntary muscle. Studies of hand grip strength and aging demonstrate a decrease in strength with age; however, there are little data regarding tongue function. The purpose of this study was to determine the relationship of increased age to tongue strength and endurance. METHODS: A pressure transducer, the Iowa Oral Performance Instrument, was used to measure maximal strength and endurance of both the hand and tongue. Ninety-nine healthy volunteers from the oral physiology component of the Baltimore Longitudinal Study of Aging were divided into four age groups, ranging from 21 to 96 years of age. A multivariate analysis of variance was used to determine differences in strength and endurance between age groups and genders. Regression analysis was done to determine the relationship of strength and endurance with age. RESULTS: Gender analysis indicated that both tongue and hand strength were greater in males; however, tongue and hand endurance demonstrated no gender differences. The strength in both the tongue and hand decreased with age. Individuals over the age of 79 years showed statistically decreased tongue strength, and individuals over the age of 59 years showed statistically decreased hand strength. There was no significant change in the tongue and hand endurance with age. CONCLUSIONS: The results of this study suggest that tongue function is gender- and age-dependent and follows the same trends as hand function. Tongue strength is decreased in older individuals and females, while tongue endurance is gender- and age-independent.

The relationship between dehydration and parotid salivary gland function in young and older healthy adults.

BACKGROUND: Saliva is essential for the maintenance of oral health. The primary constituent of saliva is water and, traditionally, decreased body water homeostasis has been linked with salivary dysfunction. This is consistent with the greater prevalence of dehydration and salivary gland dysfunction among the elderly. However, this association between dehydration and salivary dysfunction has never been tested using objective criteria. The purpose of this study was to determine the effect of body dehydration upon parotid salivary flow rates in young and older healthy adults. METHODS: Twelve young (20-40 years) and 12 older (60-80 years) healthy subjects abstained from food and beverage intake for 24 h (dehydration) and then underwent intravenous rehydration to replace all lost weight. Unstimulated and stimulated parotid salivary flow rates, weight, hematocrit, hemoglobin, serum sodium, plasma protein, creatinine, serum, and urine osmolality values were assessed at baseline, 24 h, and 1 h after the completion of rehydration. RESULTS: All subjects experienced a significant decrease in weight and increased levels of hematocrit, hemoglobin, plasma protein, and creatinine during dehydration with few age-related differences. Intravenous fluid replacement increased weight and decreased hematocrit, hemoglobin, plasma protein, and creatinine back to baseline values, demonstrating that subjects were metabolically rehydrated. Unstimulated (young and older, p = .0001) and stimulated (young, p > .05; older, p = .03) parotid flow rates decreased during the 24-h dehydration period, yet did not completely return (young and older unstimulated, p < .001; young and older stimulated, p > .05) to baseline values after rehydration. CONCLUSIONS: These findings suggest that body dehydration is associated with decreased parotid salivary gland flow rates, and that these changes are generally age-independent in healthy adults. Furthermore, although subjects were metabolically rehydrated, unstimulated salivary flow rates remained significantly lower than baseline levels.

Extended stimulated parotid and submandibular secretion in a healthy young and old population.

BACKGROUND: Previous morphological studies have shown that both the human parotid and submandibular glands display age-related reductions in the proportion of fluid secreting acinar cells. In contrast, short-term functional studies of fluid secretion do not show such a consistent disparity among different-aged persons. This study compared the ability of a population of healthy young and old individuals to secret saliva from the parotid and submandibular glands for an extended period of time under conditions of intense gustatory stimulation. METHODS: Saliva was collected over 30 minutes from 30 healthy, unmedicated individuals using 10% citric acid as a gustatory stimulus. Of the 30 subjects, 15 were young (age range 27-40 years) and 15 were old (age range 60-97 years). Parotid salivary flow rates were determined every minute, and submandibular flow rates were determined at 2, 10, 20, and 30 minutes. A comparison was made between the slopes of the two groups. The slopes were derived from the average salivary flow rate at each time point. RESULTS: There was no difference in the ability of the parotid glands of young and old individuals to secrete saliva. In contrast, the submandibular glands of the elderly individuals did not show the same pattern of secretion when compared to their younger counterparts, who demonstrated increasing flow rates over the test period. CONCLUSIONS: The parotid glands of young and old persons are able to maintain high secretory ability under the stress of intense stimulation for an extended period of time. Conversely, the submandibular gland demonstrates an age-related, statistically significant difference in the pattern of fluid secretion with an intense gustatory stimulus.

Longitudinal analysis of parotid and submandibular salivary flow rates in healthy, different-aged adults.

BACKGROUND: Early studies suggested that salivary gland dysfunction was a normal sequela of aging. Recent research on healthy, different-aged adults has led to a revision of these former conclusions. Parotid gland function appears to be age-stable, yet there is no consensus on submandibular/sublingual output. To date, there have only been two longitudinal studies utilizing healthy individuals examining parotid function, and no published longitudinal studies on submandibular/sublingual output. The purpose of this study was to examine unstimulated and stimulated major salivary gland flow rates in unmedicated, essentially healthy subjects, over a 3-year period. METHODS: Thirty-seven males and females, aged 26-90 years of age, were examined twice over a 3-year period at the Clinical Center of the National Institutes of Health. All were healthy, community-dwelling adults, without systemic diseases, and not taking any medications. Unstimulated and 2% citrate-stimulated parotid and submandibular/sublingual salivary gland flow rates were assessed at both visits, and changes over time were evaluated according to the subject's age at initial visit. RESULTS: There were no significant flow rate differences over a 3-year time period for unstimulated and stimulated parotid and submandibular/sublingual flow rates. CONCLUSIONS: Major salivary gland output is aged-stable in healthy persons over a 3-year period. The data from this study suggest that salivary gland dysfunction in an older person should not be considered a normal process of aging.

Longitudinal changes in smell identification.

BACKGROUND: Cross-sectional studies have demonstrated that olfactory function diminishes with increasing age, which may impact on the safety and quality of life of older persons. To date, however, there have been no published longitudinal studies on olfaction. The purpose of this study was to examine the influence of age and gender on smell identification over a 3-year period in a group of generally healthy men and women. METHODS: Males (n = 85) and females (n = 76) between the ages of 19 and 95 years were administered the University of Pennsylvania Smell Identification Test (SIT) over a 3-year span as part of the oral physiology component of the Baltimore Longitudinal Study of Aging. A linear mixed-effects regression model was used to determine how longitudinal changes in SIT scores differ with respect to gender, history of medical problems, and use of prescription medications. RESULTS: Over the 3-year period, SIT scores diminished progressively with increased age. Women and men in the eighth decade of life experienced a decline of greater than one SIT point per year. Females consistently performed better than males in smell identification. Similar results were obtained regardless of medical problems or medication usage. CONCLUSIONS: These results extend the conclusions of previous cross-sectional olfactory studies and indicate that smell identification deteriorates progressively with greater age. Furthermore, age-related declines in olfaction occur even in the absence of overt medical problems.

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.