Rosario Ortolá

Objective frailty is a syndrome characterised by increased vulnerability to stressors, which manifests as higher death risk. Whilst guidelines for frailty management usually entails lifestyle modifications (e.g. physical exercise, diet), the mediating role of lifestyle on the excess mortality associated with frailty is unclear. This study estimates the death risk due to frailty that could be avoided with a healthy lifestyle in older adults. Subjects and Methods we analysed data from 91,906 British individuals aged ≥60 years recruited between 2006 and 2010. At baseline, frailty was identified according to Fried’s phenotype, and a four-item Healthy Lifestyle Index (HLS) was calculated based on physical activity, diet, smoking and alcohol consumption. Mortality was ascertained from baseline through 2021. A mediation analysis under the counterfactual framework was performed adjusting for the main confounders. Results during a median follow-up of 12.5 years, 9,383 deaths occurred. Frailty was directly associated with all-cause mortality (hazard ratio: 2.30 [95% confidence interval {CI} 2.07, 2.54]), and inversely associated with the HLS (ß: −0.45 points [−0.49, −0.40]). The hazard ratio [95%CI] for the direct effect of frailty on mortality was 2.12 [1.91, 2.34], whilst for the indirect effect (mediated by HLS) was 1.08 [1.07, 1.10]. The mediated proportion of HLS on mortality was 13.55% [11.26, 16.20], with physical activity having the highest proportion amongst the four HLS items (7.69% [5.00, 10.40]). Conclusions a healthy lifestyle partly mediates the association between frailty and mortality in British older adults. Since this was an exploratory mediation analysis, these results should be specifically tested in future research.

Background/Aim There has been no comprehensive examination of the potential association of SHS with broad functional limitation assessment in older adults, where functional limitations are burdensome and challenging. Methods We examined 2258 community-dwelling non-smoking older adults from the Seniors-Enrica-2-cohort. At baseline (2017) and follow-up (2019) grip strength was measured with a Jamar dynamometer, lower-extremity performance with the Short Physical Performance Battery (SPPB), overall physical function using the physical component summary (PCS) of the Spanish version of the SF-12, frailty with a Deficits Accumulation Index (DAI), and mobility limitations with the Rosow-Breslau scale. Baseline exposure to SHS was assessed by serum cotinine, and past exposure was self-reported. Cross-sectional analyses were performed using linear and logistic regression models, whereas functional performance changes were examined using repeated measures models with robust SE estimates. Results Overall, the median (IQR) serum cotinine concentration was 0.079 (0.035–0.175) ng/ml, with 20 participants presenting concentrations ≥3 ng/ml. Compared to the unexposed, fully-adjusted models showed that the highest exposure group (≥0.239 ng/ml) presented lower grip strength (mean difference: −1.05 kg; 95% CI = −1.80, -0.31) and higher DAI scores (1.52; 95% CI = 0.38, 2.66) at baseline. Similarly, in models of self-reported past exposure, never-smokers who had lived with ≥2 smokers or been exposed to higher SHS cumulative doses showed lower baseline SPPB values, higher DAI scores, and higher prevalence of mobility limitations. In prospective analyses, those in the highest quartile of baseline cotinine presented harmful SPPB [-0.24 (-0.46, -0.02)] and DAI [1.28 (0.00, 2.55)] changes, and higher risk of mobility limitations [hazard ratio: 1.64; 95% CI = 1.01, 2.68] than the unexposed. Conclusions SHS exposure over the life-course and during old age may accelerate functional decline. Implications This manuscript provides a comprehensive examination of the relationship between secondhand smoke exposure and a broad range of functional limitations in older adults. Results show that: (i) non-smokers who had been exposed to higher cumulative doses of SHS in adulthood show worse physical function than non-exposed. (ii) Exposure to SHS during old age, as measured with cotinine concentrations, is associated with accelerated short-term functional declines. (iii) The effects of SHS are stronger among older adults with chronic morbidities. (iv) Results suggest that more efforts are needed to protect older adults from passive smoking, especially to those with chronic conditions because of their potential greater vulnerability to the effects of SHS.