Associations of truncal body composition with cognitive status in patients with dementia

Body composition differences in older adults with and without Alzheimer's disease: A systematic review and meta-analysis of observational studies

BACKGROUND

Research on body composition and fat distribution in Alzheimer's disease (AD) has presented conflicting findings.

OBJECTIVE

Compare body composition and anthropometric measurements in older adults with and without AD.

METHODS

A systematic review and meta-analysis were conducted following Cochrane guidelines and PRISMA standards. MEDLINE, Embase, Scopus, LILACS, WPRIM, and the Spanish Bibliographic Index of Health Sciences were searched up to September 2024, considering observational studies that compared body composition between AD groups and controls. Outcomes included body fat percentage, body mass index (BMI), impedance, resistance, and reactance. The methodological quality and level of evidence were assessed using the Joanna Briggs Institute scale and GRADE, respectively. A random-effects meta-analysis model was used to calculate mean differences (MD).

RESULTS

Fourteen studies involving 2761 older adults were included. Older adult women with AD showed a lower body fat percentage (p < 0.01; MD = -5.07) and BMI (p = 0.05; MD = -1.28) compared to controls. Older adult men with AD had higher impedance (p = 0.01; MD = 2.05), resistance (p = 0.02; MD = 45.10), and lower reactance (p = 0.03; MD = -2.05) compared to controls. No significant differences in body fat percentage or BMI were found between older adults with and without AD, regardless of gender.

CONCLUSIONS

Women with AD showed lower body fat percentage and BMI, while men with AD had higher impedance, resistance, and lower reactance. These factors should be included in geriatric assessments for AD patients, though further research is needed to understand their link to cognitive outcomes in AD.

Differences in lean mass and sarcopenia between individuals with Alzheimer's disease and those without dementia: A systematic review and meta-analysis of observational studies

BACKGROUND

Studies have observed that individuals with Alzheimer's disease (AD) tend to have lower lean mass and higher rates of sarcopenia.

OBJECTIVE

This review aims to assess differences in lean mass, sarcopenia, and its components between individuals with AD and those without dementia (WD).

METHODS

Searches were conducted in the Medline, Web of Science, Embase, Scopus and Latin American and Caribbean Health Scientific Literature. Observational studies comparing lean mass, sarcopenia, and its components in the populations of interest were included. We used the Joanna Briggs Institute (JBI) scale to assess methodological quality. Mean differences (MD) and standardized mean differences were calculated for the meta-analyses.

RESULTS

Four studies with 2035 individuals found that those with AD had significantly lower upper and lower limb lean mass, and skeletal muscle mass index compared to WD individuals. AD individuals also had a higher sarcopenia prevalence (41.33% versus 20.66%) and significant reductions in handgrip strength, lower limb muscle strength, and gait speed compared to WD individuals. The JBI scale analysis showed high agreement among the studies (k = 1.00, p = 0.046).

CONCLUSIONS

Individuals with AD have lower lean mass, higher rates of sarcopenia, and reduced muscle function compared to those without dementia. While the results suggest the need for early screening programs and integrated therapeutic interventions to improve clinical outcomes and quality of life for individuals with AD, it is important to consider that biases inherent in observational studies may compromise the quality of the evidence. Therefore, further research, preferably clinical trials, is needed to confirm these associations.

Sarcopenia in patients with dementia: correlation of temporalis muscle thickness with appendicular muscle mass

Cognitive decline is one of the most relevant signs of sarcopenia; however, it is challenging to perform tests for sarcopenia in patients with dementia. In a recent study, temporalis muscle thickness (TMT), an alternative to appendicular muscle mass (ASM), was found to be a valid index for screening sarcopenia. This study aimed to determine whether TMT correlates with ASM and evaluate the relationship between TMT and cognitive function in dementia patients. We recruited patients with a complaint of memory loss who visited the Memory Clinic of Konkuk University Medical Center between November 2014 and December 2020. Patients with probable Alzheimer's disease (AD) without weakness were included. TMT was measured on axial T1-weighted magnetic resonance (MR) images, perpendicular to the long axis of the temporal muscle, at the orbital roof level. ASM was measured using body dual-energy X-ray absorptiometry (DXA). It was calculated as the sum of lean soft tissue mass in the arms and legs, and the value by ASM divided by height squared was used. Inter-rater reliability and intra-rater reliability were good and excellent, respectively. We found a correlation between TMT and skeletal ASM, which was obtained from cranial MR images and DXA, respectively (r = 0.379, p = 0.001). TMT was negatively correlated with age (r =  - 0.296, p = 0.014) and positively correlated with body mass index (BMI) (r = 0.303, p = 0.012). Additionally, TMT was correlated with MMSE (r = 0.350, p = 0.003). After adjusting for educational years, there was still a correlation between TMT and MMSE (r = 0.256, p = 0.038). This study demonstrated that TMT correlates with ASM and cognitive function in patients with dementia. Measuring TMT using cranial MR images could help diagnose sarcopenia accessibly and assess cognitive function in patients with dementia.

[Neuropsychiatric symptoms in patients with mild cognitive impairment]

OBJECTIVE

To study the prevalence of neuropsychiatric symptoms (NPS) in patients with mild cognitive impairment (MCI) who asked for help in memory clinics.

MATERIAL AND METHODS

We analysed data on 729 patients with MCI (average age 76.6 years, average MMSE score 25.3), who underwent a course of cognitive neurorehabilitation in a specialized department - a memory clinic. A Russian version of Neuropsychiatric Inventory (NPI) was used. We compared the indicators for the main psychometric scales for the diagnosis of MCI in comparison with the dynamics of NPS.

RESULTS

The prevalence rates for NPS differed in part from those reported in the literature. The most common symptom was anxiety (54.7%) and irritability (56.5%), while euphoria, as well as delusions and hallucinations were not detected. All disorders significantly reduced at the end of the rehabilitation program.

CONCLUSION

MCI influences the level of functioning and social interaction in older patients and mediates the quality of life. Thus, given the increase in life expectancy, it is necessary to introduce new methods of examination applicable in the practice of psychiatrists to diagnose and rehabilitate such patients. NPS turned out to be widespread in MCI, but may reduce during the course of complex neurorehabilitation.