Plasma acylcarnitines as metabolic signatures of declining health-related quality of life measure in community-dwelling older adults: a combined cross-sectional and longitudinal pilot study.

BACKGROUND: Health-related quality of life (HRQoL) measures are predictors of adverse health outcomes in older adults. Studies have demonstrated cross-sectional associations between HRQoL measures and blood-based biochemical markers. Acylcarnitines (ACs) are a class of metabolites generated in the mitochondria and are predictive of multiple geriatric syndromes. Changes in ACs reflect alterations in central carbon metabolic pathways. However, the prospective relationship between plasma acylcarnitines and declining HRQoL has not been examined. This study aimed to investigate both cross-sectional and longitudinal associations of baseline ACs with baseline and declining EuroQol-5 Dimension/ EuroQol Visual Analogue Scale (EQ-5D/ EQ-VAS) in community-dwelling older adults. METHODS: 120 community-dwelling older adults with EQ-5D/ EQ-VAS measurements at baseline and follow-up were included. We quantified ACs at baseline using targeted plasma metabolomics profiling. Multivariate regressions were performed to examine cross-sectional and longitudinal associations between the measures. RESULTS: Cross-sectionally, ACs showed no significant associations with either EQ-5D index or EQ-VAS scores. Longitudinally, multiple baseline short-chain ACs were significantly and inversely associated with declining EQ-5D index score, explaining up to 8.5% of variance in the decline. CONCLUSIONS: Within a cohort of community-dwelling older adults who had high HRQoL at baseline, we showed that short-chain acylcarnitines are independent predictors of declining HRQoL. These findings reveal a novel association between central carbon metabolic pathways and declining HRQoL. Notably, dysregulation in mitochondrial central carbon metabolism could be detected prior to clinically important decline in HRQoL, providing the first evidence of objective biomarkers as novel predictors to monitor HRQoL in non-pharmacological interventions and epidemiology.

Novel metabolomics markers are associated with pre-clinical decline in hand grip strength in community-dwelling older adults.

BACKGROUND: Hand grip strength (HGS) has been proposed as a robust predictor for frailty and sarcopenia. Hence, identifying biomarkers for declining HGS accompanying aging could deepen our understanding of the biological underpinnings, informing pre-emptive intervention. Acylcarnitines (ACs) are metabolites generated by fatty acid metabolism in the mitochondria and are dysregulated in multiple disorders affecting the musculature. However, they have not been comprehensively profiled and examined regarding their utility in predicting variability in declining HGS, longitudinally. Thus, we aimed to: 1) validate previous findings on insignificant cross-sectional association between ACs and HGS, and 2) examine whether baseline ACs were associated with both decline and variability in HGS over 18 months, in community-dwelling older adults. METHODS: We included participants who had HGS measured with dynamometer longitudinally (N = 121). We quantified ACs by targeted plasma metabolomics profiling. Multivariable linear regressions were then performed. RESULTS: Cross-sectionally, ACs were not significantly associated with HGS. Longitudinally, baseline short-chain dicarboxylic and hydroxylated acylcarnitines (AC-DC/-OH) levels were inversely associated with and significantly explained the variability in 18-month decline in HGS. A specific AC species, the C4-OH, accounted for most of the variance explained. CONCLUSIONS: We showed novel biomarkers for declining HGS, furthering molecular understanding and informing nutritional pre-emptive programs.

The Role of a Multicomponent Home-Health Intervention in Reducing Caregiver Stress in Singapore: A Qualitative Study.

Purpose: The relationship between caregiving and negative health outcomes is well established in the literature. Previous studies have shown that community-based programs reduce caregiver stress. However, the mechanisms by which this happens have not been well investigated. This qualitative study examines caregivers' experiences as a part of the Aging-In-Place intervention, a home-health program in Singapore targeted at frequently hospitalized patients and their caregivers. Method: We interviewed 32 caregivers to study the underlying processes by which caregiver stress was ameliorated. Transcripts from semistructured interviews were analyzed thematically within the theoretical framework of the stress process model. Results: Primary stressors related to routine patient care were reduced through the intervention program that provided health monitoring to patients and facilitated linkages to community-based services. Increased access to advice and medical information provided by intervention staff reduced caregivers' uncertainty, a substantial secondary stressor. Caregivers who employed a foreign domestic worker (FDW) gained additional reductions in both primary and secondary stressors. Discussion: The multidimensional home-health intervention reduced both primary and secondary stressors for caregivers. FDWs constituted a resource that caregivers could rely on and the training provided to FDWs by intervention staff further reduced caregiver stress. Implications for program planning and future research are discussed.

Effect of caregiving relationship and formal long-term care service use on caregiver well-being.

AIM: Despite efforts to revise the traditional long-term care (LTC) model, informal caregivers continue to provide a substantial amount of support to older adults as front-line care providers. The present study aimed to understand the effect of informal caregiving on caregivers' well-being in Singapore with respect to different types of patient-caregiver relationships. Second, this study examined the association between formal LTC service use and caregivers' well-being. METHODS: Two waves of data for 781 dyads of patients with LTC needs and their caregivers from a longitudinal study were analyzed. Multilevel regression models were used to examine the association between caregivers' well-being (self-rated general health, stress level and quality of life) and LTC service use among different patient-caregiver relationships. RESULTS: Spousal caregivers reported significantly lower quality of life compared with adult children caregivers. Non-immediate family caregivers showed better overall well-being compared with spouse and adult children caregivers. Caregivers of patients referred to nursing homes reported higher levels of stress and poorer self-rated general health compared with caregivers of patients referred to community-based services. Spouse and non-immediate family caregivers of patients who utilized nursing home or home-based services presented poorer self-rated general health than caregivers of the patients who did not use any formal services. CONCLUSIONS: Developing a better understanding of the associations between well-being and formal LTC service use for different types of patient-caregiver relationships is critical for policy makers and healthcare providers who aim to create holistic systems of care. Geriatr Gerontol Int 2017; 17: 1714-1721.

Community-Based Long-Term Care Services: If We Build It, Will They Come?

OBJECTIVE: This study examines the relationship between caregivers' perception of community-based long-term care (CBLTC) services and the service use. METHOD: We used first two waves of the longitudinal data set of 1,416 dyads of care recipients and their caregivers in Singapore. Four perceived attributes of LTC services--service quality, convenience, social connectedness, and affordability--were measured on a 5-point scale. RESULTS: Among the four perceived attributes, perceived affordability was significantly associated with future utilization for all types of CBLTC services. Perceived service quality and convenience was significantly associated with center-based LTC services use. DISCUSSION: Caregivers are critically involved in the decision of using CBLTC services, and their perception of service characteristics is significantly associated with the uptake of CBLTC services. It is important to incorporate both care recipients' and caregivers' needs and preferences when designing and promoting integrated health care delivery models.