Associations between body composition and cognitive function in an elderly Korean population: A cohort-based cross-sectional study.

ABSTRACT: The prevalence of obesity as well as cognitive impairment increases with age. Previous studies showed that obesity is associated with an increased risk of cognitive impairment and dementia. Body composition changes occur as part of the aging process; therefore, the assessment of obesity in elderly populations should include body composition as well as body weight. This study investigated the relationship between body mass index (BMI), body composition, and cognitive function in a community-dwelling elderly Korean population.This cohort-based cross-sectional analysis included 2386 elderly participants aged between 70 and 84 years from the Korean Frailty and Aging Cohort Study for 2016 to 2017. To investigate the relationship between body composition and cognitive function in community-dwelling individuals, BMI and body composition, including total and trunk fat mass and fat-free mass, were measured by dual-energy X-ray absorptiometry. Fat mass index (FMI), trunk fat mass index (TFMI), and fat-free mass index (FFMI) were used to represent the body composition. A short form of the Korean version of the Consortium to Establish a Registry for Alzheimer disease was used to assess cognitive function. To evaluate the relationship between variables, simple and fully adjusted multivariable analyses were performed using generalized linear regression models.The mean ages were 76.8 years for males and 76.1 years for females. The BMI of male participants was significantly lower than that of females (23.9 ±â€Š2.89 vs 24.7 ±â€Š3.02 kg/m2, P < .001). Among body composition parameters, the differences in FMI (6.44 ±â€Š1.97 vs 9.29 ±â€Š2.3 kg/m2), TFMI (3.68 ±â€Š1.33 vs 5.03 ±â€Š1.43 kg/m2), and FFMI (17.4 ±â€Š1.64 vs 15.3 ±â€Š1.39 kg/m2) were statistically significant. In linear regression analyses, BMI, FMI, and TFMI showed significant positive correlations with mini-mental state examination in the Korean version of the CERAD assessment packet; wordlist memory, recall, and recognition; and frontal assessment battery only in males. The significant positive correlations persisted even after fully adjusting for age, education periods, location of residence, depression, marriage, annual income, presence of diabetes mellitus, dyslipidemia, and hypertension. However, no significant correlations in either sex were observed between FFMI and cognitive functions in the fully adjusted models.In this study, BMI, and fat mass-related indexes including FMI and TFMI showed a positive linear correlation with cognitive functions but not FFMI. Moreover, the findings were significant only in men. Besides the difference between sexes, the results of this study showed a more apparent correlation in fat mass than in fat-free mass that comprises body weight.

Association between vitamin D deficiency and cognitive function in the elderly Korean population: A Korean frailty and aging cohort study.

It is well known that vitamin D (VitD) plays an important role in bone and calcium metabolism in the human body. VitD has additional roles in the body including modulation of cell growth, neurogenesis, neuroprotection, detoxification, immune function, and reduction of inflammation. Recent studies reveal insufficiency of VitD as a risk factor for cognitive decline or dementia. VitD has a role in normal brain function; insufficiency of VitD may lead to decreased memory and cognitive function.Using 2 years of baseline data from Korean frailty and aging cohort study, 2990 subjects (1415 men and 1575 women) were recruited. A short form of Korean version of the consortium to establish a registry for Alzheimer disease (CERAD-K), an assessment of cognitive status in patients with dementia was used. Among CERAD-K tests, we included word list memory/recall/recognition, digit span (forward, backward), trail making test (TMT) A, and mini-mental state examination in the Korean version of the CERAD assessment packet (MMSE-KC). Serum samples were collected and 25-hydroxyvitamin D (25(OH)D) was measured. Serum 25(OH)D concentrations were classified into clinically relevant categories as: deficient (<10 nmol/L), insufficient (10-30 nmol/L), and sufficient (≥30 nmol/L).The mean age of participants was 76.5 ±â€Š3.9 years, and 52.7% were women. Among 2990 participants, 119 (4.0%) were classified as 25(OH)D deficient and 2253 (75.3%) as insufficient. Only 618 (20.7%) participants were sufficient for 25(OH)D. Among them performance in MMSE-KC, TMT A, and digit span tests was better in sufficient, insufficient, and deficient groups, which was statistically significant (P < .05). However, in multivariable regression analysis after adjusting for age, sex, body mass index, education, center, seasonality, physical activity, and alcohol use, association between 25(OH)D and cognitive function was not statistically significant.Although, when comparing VitD levels, there were differences in cognitive tests among the groups, fully adjusted analysis did not show any association. This result suggests that cognition was not affected by VitD levels alone but also population and sociological variables. In a fully adjusted model, there was no statistically significant association between VitD and cognitive function in the elderly Koreans in logistic regression analysis.

Correlations between swallowing function and acoustic vowel space in stroke patients with dysarthria.

BACKGROUND: Dysphagia and dysarthria tend to coexist in stroke patients. Dysphagia can reduce patients' quality of life, cause aspiration pneumonia and increased mortality. OBJECTIVE: To evaluate correlations among swallowing function parameters and acoustic vowel space values in patients with stroke. METHODS: Data from stroke patients with dysarthria and dysphagia were collected. The formant parameter representing the resonance frequency of the vocal tract as a two-dimensional coordinate point was measured for the /a/, /ae/, /i/, and /u/vowels, and the quadrilateral vowel space area (VSA) and formant centralization ratio (FCR) were measured. Swallowing function was evaluated by a videofluoroscopic swallowing study (VFSS) using the videofluoroscopic dysphagia scale (VDS) and penetration aspiration scale (PAS). Pearson's correlation and linear regression analyses were used to assess the correlation of VSA and FCR to VDS and PAS scores. RESULTS: Thirty-one stroke patients with dysphagia and dysarthria were analyzed. VSA showed a negative correlation to VDS and PAS scores, while FCR showed a positive correlation to VDS score, but not to PAS score. VSA and FCR were significant factors for assessing dysphagia severity. CONCLUSIONS: VSA and FCR values were correlated with swallowing function and may be helpful in predicting dysphagia severity associated with stroke.