Increased Salt Intake for Orthostatic Intolerance Syndromes: A Systematic Review and Meta-Analysis.

BACKGROUND: Guidelines recommend increased salt intake as a first-line recommendation in the management of symptomatic orthostatic hypotension and recurrent syncope. There have been no systematic reviews of this intervention. We sought to summarize the evidence for increased salt intake in patients with orthostatic intolerance syndromes. METHODS: We conducted a systematic review and meta-analysis of studies in PubMed, EMBASE, and CINAHL. Interventional studies that increased salt intake in individuals with orthostatic intolerance syndromes were included. Primary outcome measures included incidence of falls and injuries, and rates of syncope and presyncope. Secondary outcome measures included other orthostatic intolerance symptoms, blood pressure, and heart rate. RESULTS: A total of 14 studies were eligible, including participants with orthostatic hypotension, syncope, postural orthostatic tachycardia syndrome, and idiopathic orthostatic tachycardia (n = 391). Mean age was 35.6 (± 15) years. All studies were small and short-term (<60 mins-90 days). No study reported on the effect of increased salt intake on falls or injuries. Meta-analysis demonstrated that during head-up tilt, mean time to presyncope with salt intake increased by 1.57 minutes (95% confidence interval [CI], 1.26-1.88), mean systolic blood pressure increased by 12.27 mm Hg (95% CI, 10.86-13.68), and mean heart rate decreased by -3.97 beats per minute (95% CI, -4.08 to -3.86), compared with control. Increased salt increased supine blood pressure by 1.03 mm Hg (95% CI, 0.81 to 1.25). Increased salt intake resulted in an improvement or resolution of symptoms in 62.3% (95% CI, 51.6 to 72.6) of participants in short-term follow-up studies (mean follow-up of 44.3 days, 6 studies; n=91). Methodological quality of studies were low with high statistical heterogeneity in all meta-analyses. CONCLUSIONS: Our meta-analysis provides low-quality evidence of a short-term improvement in orthostatic intolerance with increased salt intake. There were no clinical trials demonstrating the efficacy and safety of increased salt intake on long-term clinical outcomes. Overall, there is a paucity of clinical trial evidence to support a cornerstone recommendation in the management of orthostatic intolerance syndromes.

Mediating the relationship between loneliness and cognitive function: the role of depressive and anxiety symptoms.

Objective: To evaluate the relationship between loneliness and cognitive functioning, and whether depressive and anxiety symptoms have intermediate roles therein.Methods: Information about 7,433 participants of the Irish Longitudinal Study on Ageing (a prospective, representative cohort study), aged over 50, was collected at three time-points two years apart, and analysed using Structural Equation Modelling to assess whether depressive and anxiety symptoms mediate the relationship between loneliness and cognitive functioning. Cognitive functioning was measured as a latent factor, with four indicators: measures of immediate and delayed word recall, verbal fluency, and a global measure (the MMSE). Loneliness was measured using the UCLA Loneliness scale, depressive symptoms using the CES-D-ML scale, and anxiety symptoms using the HADS-A scale.Results: Loneliness at time-point 1 predicted cognitive functioning at time-point 3, ß = -0.103, p < 0.001, and depressive (ß = 0.426, p < 0.001) and anxiety (ß = 0.410, p < 0.001) symptoms at time-point 2. Depressive (ß = -0.020, p = 0.001) but not anxiety (ß = -0.000, p = 0.658) symptoms mediated the relationship between loneliness and cognitive functioning, total effect: ß = -0.123, p < 0.001.Conclusion: The relationship between loneliness and cognitive functioning is in part explained by its relationship with depressive symptoms. Statistically, the mediation model helps us understand possible mechanisms through which loneliness impacts cognitive functioning. Results have implications for cognitive functioning interventions for older adults, and imply that loneliness is also a worthwhile target for intervention.

Lonely SARTs: loneliness and sustained attention in the Irish longitudinal study of aging.

Based on biologically plausible mechanisms and previous research, it is possible to hypothesize a reciprocal association between sustained attention and loneliness. We investigated this association using a cross-lagged modeling approach. Using data from 6,239 participants aged over 50 in TILDA, a nationally representative study of aging, we used structural equation models to investigate potential cross-lagged associations between sustained attention and loneliness, measured at baseline and again after four years. Sustained attention at baseline had a small association with loneliness four years later, but loneliness at baseline was not associated with sustained attention at follow-up. Auto-regressive associations were strong for both loneliness over time and sustained attention over time. Sustained attention may account for a small proportion of the variance in loneliness over time among older adults, and may constitute a risk factor in the development of loneliness. Implications for the identification of at-risk individuals and the prevention of loneliness are discussed.

Investigation of antihypertensive class, dementia, and cognitive decline: A meta-analysis.

OBJECTIVE: High blood pressure is one of the main modifiable risk factors for dementia. However, there is conflicting evidence regarding the best antihypertensive class for optimizing cognition. Our objective was to determine whether any particular antihypertensive class was associated with a reduced risk of cognitive decline or dementia using comprehensive meta-analysis including reanalysis of original participant data. METHODS: To identify suitable studies, MEDLINE, Embase, and PsycINFO and preexisting study consortia were searched from inception to December 2017. Authors of prospective longitudinal human studies or trials of antihypertensives were contacted for data sharing and collaboration. Outcome measures were incident dementia or incident cognitive decline (classified using the reliable change index method). Data were separated into mid and late-life (>65 years) and each antihypertensive class was compared to no treatment and to treatment with other antihypertensives. Meta-analysis was used to synthesize data. RESULTS: Over 50,000 participants from 27 studies were included. Among those aged >65 years, with the exception of diuretics, we found no relationship by class with incident cognitive decline or dementia. Diuretic use was suggestive of benefit in some analyses but results were not consistent across follow-up time, comparator group, and outcome. Limited data precluded meaningful analyses in those ≤65 years of age. CONCLUSION: Our findings, drawn from the current evidence base, support clinical freedom in the selection of antihypertensive regimens to achieve blood pressure goals. CLINICAL TRIALS REGISTRATION: The review was registered with the international prospective register of systematic reviews (PROSPERO), registration number CRD42016045454.

Comparisons of the discrepancy between loneliness and social isolation across Ireland and Sweden: findings from TILDA and SNAC-K.

PURPOSE: Loneliness may have different cultural meanings in different countries. This may manifest as differing levels of Social Asymmetry-the discrepancy between loneliness and social isolation. Since loneliness is thought to be low in Sweden relative to more southerly countries, we hypothesised that more number of individuals would also fall into the "discordant robust" category of Social Asymmetry, i.e. that more individuals in Sweden would have lower loneliness levels relative to social isolation than in Ireland. We also explored the clinical relevance of Social Asymmetry in both countries, by examining its association with cognitive functioning. METHODS: We derived Social Asymmetry metrics in two representative cohort studies: the Irish Longitudinal Study on Ageing (TILDA) and the Swedish National Study on Aging and Care in Kungsholmen (SNAC-K). Data pertaining to a dementia-free sample of 4565 Irish participants and 3042 Swedish participants, all aged over 60 years, were analysed using a multilevel modelling approach, with country as a higher-order variable. RESULTS: Contrary to the expected, more individuals in Ireland were "discordant robust" than in Sweden. We also found evidence for superior performance in global cognitive functioning among those in the "discordant robust" category relative to those in the discordant susceptible (i.e. those with higher levels of loneliness than social isolation) category, ß = 0.61, p < .001, across both countries. CONCLUSIONS: Irish older adults may be more robust to the impact of social isolation on loneliness than those in the Swedish cohort. Social Asymmetry was related to cognitive functioning in both countries, suggesting that Social Asymmetry is a clinically relevant construct.

Cardiovascular risk factors and frailty in a cross-sectional study of older people: implications for prevention.

Objective: to examine the associations of cardiovascular disease (CVD) and cardiovascular risk factors with frailty. Design: a cross-sectional study. Setting: the Irish Longitudinal Study on Ageing (TILDA). Participants: frailty measures were obtained on 5,618 participants and a subset of 4,330 participants with no prior history of CVD. Exposures for observational study: cardiovascular risk factors were combined in three composite CVD risk scores (Systematic Coronary Risk Evaluation [SCORE], Ideal Cardiovascular Health [ICH] and Cardiovascular Health Metrics [CHM]). Main outcome measures: a frailty index (40-items) was used to screen for frailty. Methods: the associations of CVD risk factors with frailty were examined using logistic regression. Results: overall, 16.4% of participants had frailty (7.6% at 50-59 years to 42.5% at 80+ years), and the prevalence was higher in those with versus those without prior CVD (43.0% vs. 10.7%). Among those without prior CVD, mean levels of CVD risk factors were closely correlated with higher frailty index scores. Combined CVD risk factors, assessed using SCORE, were linearly and positively associated with frailty. Compared to low-to-moderate SCOREs, the odds ratio (OR) (95% confidence interval, CI) of frailty for those with very high risk was 3.18 (2.38-4.25). Conversely, ICH was linearly and inversely associated with frailty, with an OR for optimal health of 0.29 (0.21-0.40) compared with inadequate health. Conclusions: the concordant positive associations of SCORE and inverse associations of ICH and CHM with frailty highlight the potential importance of optimum levels of CVD risk factors for prevention of disability in frail older people.

Mediators of the relationship between social activities and cognitive function among older Irish adults: results from the Irish longitudinal study on ageing.

OBJECTIVE: Evidence points to an association between social and leisure activity (SLA) engagement and cognitive outcomes, but the mechanisms underlying this link remain unknown. We aimed to investigate three potential mechanisms: Vascular function, Perceived Stress, and Cognitive Reserve. METHODS: With data from 8163 adults aged over 50 in the Irish Longitudinal Study of Ageing, we used a structural equation model to evaluate Vascular Function and Perceived Stress as potential mediators, and Cognitive Reserve as a potential antecedent in the relationship between SLA at baseline (2009), and cognitive outcomes collected at a two-year follow-up point (2011). RESULTS: Cognitive Reserve was strongly associated both with cognitive outcomes (ß = 0.306; p < 0.001) and with SLA (ß = 0.694; p < 0.001). Perceived stress (ß = 0.018) acted as a significant mediator in the relationships between SLA and cognitive outcomes (p < 0.001), although Vascular Function did not (ß = 0.000). CONCLUSION: These results indicate that SLA may protect cognitive function partly because of its association with cognitive reserve, and partly through its impact on perceived stress. Results have policy implications for those interested in facilitating SLA to protect cognitive outcomes among older adults.

Orthostatic hypotension and subjective sleep quality in older people.

Poor sleep quality and orthostatic hypotension are common complaints in an older population, and both are related to factors such as polypharmacy and depression. However, it is not known whether there is a direct association between the two. Our objective is to investigate a potential association between orthostatic blood pressure response and subjective sleep quality in older people. A within-subjects, cross-sectional design embedded in a larger longitudinal study design. Participants were recruited from the community to visit the TRIL clinic at St James's Hospital, where they underwent a structured medical and psychosocial assessment. A total of 505 community dwelling adults aged 60+ (321 females, mean age 72.44) were participated in this study. Orthostatic blood pressure responses were recorded during an active stand using Finometer equipment, and health-related factors such as pain ratings, co-morbidities, polypharmacy, timed up and go, Mini-Mental State Examination score, body mass index, as well as depression, anxiety, age and gender, were also recorded. Self-reported sleep quality was also assessed using the Pittsburgh Sleep Quality Index. The results showed that timed up and go, polypharmacy, depression, anxiety, gender and delayed recovery of blood pressure at orthostasis were associated with subjective poor sleep quality. There is an association between subjective sleep quality and delayed recovery of blood pressure at orthostasis, independent of mental health or polypharmacy effects, in older adults. This link may have implications for the management of sleep disorders in older people.