Plant-Based Diets and Risk of Multimorbidity: The Health and Retirement Study.

BACKGROUND: Plant-based diets have gained attention due to their beneficial effects against major chronic diseases, although their association with multimorbidity is mostly unknown. OBJECTIVES: We examined the association between the healthful (hPDI) and unhealthful plant-based diet indices (uPDI) with multimorbidity among middle-aged and older adults from the United States. METHODS: Data on 4262 adults aged >50 y was obtained from the 2012-2020 Health and Retirement Study (HRS) and 2013 Health Care and Nutrition Study (HCNS). Food consumption was collected at baseline with a food frequency questionnaire and 2 PDIs were derived: the hPDI, with positive scores for healthy plant foods and reverse scores for less healthy plant foods and animal foods; and the uPDI, with only positive scoring for less healthy plant foods. Complex multimorbidity, defined as ≥3 coexistent conditions, was ascertained from 8 self-reported conditions: hypertension, diabetes, cancer, chronic lung disease, heart disease, stroke, arthritis, and depression. Cox proportional hazards models were used to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS: After a median follow-up of 7.8 y, we documented 1202 incident cases of multimorbidity. Compared with the lowest quartile, higher adherence to the hPDI was inversely associated with multimorbidity (HR for quartile 3: 0.77; 95% CI: 0.62, 0.96 and HR for quartile 4: 0.79; 95% CI, 0.63, 0.98; P-trend = 0.02). In addition, a 10-point increment in the hPDI was associated with a 11% lower incidence of multimorbidity (95% CI: 1, 20%). No significant associations were found for the uPDI after adjusting for sociodemographic and lifestyle factors. CONCLUSIONS: Higher adherence to the hPDI was inversely associated with multimorbidity among middle-aged and older adults. Plant-based diets that emphasize consumption of high-quality plant foods may help prevent the development of complex multimorbidity.

Cross-sectional Association Between Plasma Biomarkers and Multimorbidity Patterns in Older Adults.

Multimorbidity is the simultaneous presence of 2 or more chronic conditions. Metabolomics could identify biomarkers potentially related to multimorbidity. We aimed to identify groups of biomarkers and their association with different multimorbidity patterns. Cross-sectional analyses were conducted within the Seniors-ENRICA-2 cohort in Spain, with information from 700 individuals aged ≥65 years. Biological samples were analyzed using high-throughput proton nuclear magnetic resonance metabolomics. Biomarker groups were identified with exploratory factor analysis, and multimorbidity was classified into 3 types: cardiometabolic, neuropsychiatric, and musculoskeletal. Logistic regression was used to estimate the association between biomarker groups and multimorbidity patterns, after adjusting for potential confounders including sociodemographics, lifestyle, and body mass index. Three factors were identified: the "lipid metabolism" mainly reflected biomarkers related to lipid metabolism, such as very-low-density lipoprotein and low-density lipoprotein cholesterol; the "high-density lipoprotein cholesterol" mainly included high-density lipoprotein cholesterol subclasses and other lipids not included in the first factor; and the "amino acid/glycolysis/ketogenesis," composed of some amino acids, glycolysis-related metabolites, and ketone bodies. Higher scores in the "lipid metabolism" factor were associated with a higher likelihood of cardiometabolic multimorbidity, odds ratio for tertile 3 versus tertile 1 was 1.79 (95% confidence interval: 1.17-2.76). The "high-density lipoprotein cholesterol" factor was associated with lower odds of cardiometabolic multimorbidity [0.51 (0.32-0.82)], and the "amino acid/glycolysis/ketogenesis" factor was associated with more frequent cardiometabolic multimorbidity [1.85 (1.18-2.90)]. Different metabolomic biomarkers are associated with different multimorbidity patterns; therefore, multiple biomarker measurements are needed for a complete picture of the molecular mechanisms of multimorbidity.

Diet Quality and Multimorbidity in Older Adults: A Prospective Cohort Study.

BACKGROUND: The role of diet quality in the accumulation of multiple chronic conditions is mostly unknown. This study examined diet quality in association with the number of chronic conditions and the rate of multimorbidity development among community-dwelling older adults. METHODS: We used data from 2 784 adults aged ≥65 years from the Seniors-ENRICA 2 cohort. Diet quality was assessed at baseline (2015-17) with the Alternate Healthy Eating Index-2010 (AHEI-2010) and the Mediterranean Diet Adherence Screener (MEDAS). Information on medical diagnoses was obtained from electronic clinical records up to 2021. RESULTS: Higher adherence to the AHEI-2010 was associated with a lower number of total chronic conditions (ß [95% CI] quartile 4 vs 1: -0.57 [-0.86 to 0.27], p trend < .001] and cardiometabolic conditions (-0.30 [-0.44 to -0.17], p trend < .001) at baseline, while higher adherence to the MEDAS was associated with a lower number of total chronic conditions (-0.30 [-0.58 to -0.02], p trend = .01) and neuropsychiatric and neurodegenerative conditions (-0.09 [-0.17 to -0.01], p trend = .01). After a median follow-up of 5.2 years (range: 0.1-6.1 years) higher adherence to the AHEI-2010 was associated with a lower increase in chronic conditions (ß [95% confidence interval] quartile 4 vs 1: -0.16 [-0.30 to -0.01], p trend = .04) and with lower rate of chronic disease accumulation. CONCLUSIONS: Higher diet quality, as measured by the AHEI-2010, was associated with a lower number of chronic health conditions and a lower rate of multimorbidity development over time.

Dietary Micronutrient Adequacy and Risk of Multimorbidity in Community-dwelling Older Adults.

BACKGROUND: Multimorbidity refers to the coexistence of multiple chronic health conditions. The effect of nutritional adequacy on multimorbidity is mostly unknown. OBJECTIVE: The aim of this study was to assess the prospective association between dietary micronutrient adequacy and multimorbidity among community-dwelling older adults. METHODS: This cohort study included 1461 adults aged ≥65 y from the Seniors-ENRICA II cohort. Habitual diet was assessed at baseline (2015-2017) with a validated computerized diet history. The intakes of 10 micronutrients (calcium, magnesium, potassium, vitamins A, C, D, E, zinc, iodine, and folate) were expressed as percentages relative to the dietary reference intakes, with higher scores indicating greater adequacy. Dietary micronutrient adequacy was computed as the average of all the nutrient scores. Information on medical diagnosis was obtained from the electronic health records up to December 2021. Conditions were grouped into a comprehensive list of 60 categories and occurrence of multimorbidity was defined as having ≥6 chronic conditions. Analyses were conducted using Cox proportional hazard models adjusted for relevant confounders. RESULTS: The mean age was 71.0 y (SD: 4.2) and 57.8% of participants were males. During a median follow-up of 4.79 y, we documented 561 incident cases of multimorbidity. Participants in the highest (85.8%-97.7%) versus the lowest tertile (40.1%-78.7%) of dietary micronutrient adequacy had a low risk of multimorbidity [fully adjusted hazard ratio (95% confidence interval): 0.75 (0.59-0.95); P-trend: 0.02]. A 1-SD increment in minerals and vitamins adequacy was associated with a low risk of multimorbidity, although estimates were attenuated after additional adjustment for the opposite subindex [minerals subindex: 0.86 (0.74-1.00); vitamins subindex: 0.89 (0.76-1.04)]. No differences were observed by strata of sociodemographic and lifestyle factors. CONCLUSION: A high micronutrient index score was associated with low risk of multimorbidity. Improving the dietary micronutrient adequacy could prevent multimorbidity among older adults. CLINICAL TRIAL REGISTRY: clinicaltrials.govNCT03541135.

Leucine Intake and Risk of Impaired Physical Function and Frailty in Older Adults.

BACKGROUND: Leucine is suggested to play a central role in age-related physical decline, but the effect of dietary leucine intake on physical functioning is uncertain. We examined the prospective association between dietary leucine intake and impaired lower-extremity function (ILEF) and frailty in older adults. METHODS: We used data from 2 956 adults aged ≥60 and older from the Seniors-ENRICA cohort. At baseline (2008-2010) and in 2012, dietary information was obtained with a validated computerized face-to-face diet history, from which energy-adjusted cumulative leucine intake per body weight was calculated. Participants were followed up through 2017 to assess incident ILEF, ascertained with the Short Physical Performance Battery, and incident frailty, according to the Fried phenotype criteria. Statistical analysis was performed with Cox models adjusted for the main potential confounders. RESULTS: During follow-up, we identified 515 incident cases of ILEF and 241 of frailty. Compared with participants in the lowest tertile of leucine intake (35.5-89.0 mg/kg/d), those in the highest tertile (107.4-372.5 mg/kg/d) had a lower risk of ILEF (fully adjusted hazard ratio [95% confidence interval]: 0.70 [0.53-0.93], p trend: .01) and of frailty (0.63 [0.41-0.96], p trend: .03]. A higher consumption of important sources of leucine in this population, including unprocessed beef, oily and white fish, and bread, were also associated with a lower risk of incident ILEF and frailty. CONCLUSIONS: Higher leucine intake was associated with reduced risk of ILEF and frailty. Dietary leucine, obtained from foods rich in high-quality protein, could be a key nutrient to prevent age-related physical function decline in older adults.

Association of Zinc Intake With Risk of Impaired Physical Function and Frailty Among Older Adults.

BACKGROUND: Zinc could be a target nutrient in the prevention of physical impairment and frailty in older adults due to its anti-inflammatory/antioxidant properties. However, prospective studies evaluating this inquiry are scarce. Thus, we aimed to assess the association between zinc intake and impaired lower-extremity function (ILEF) and frailty among community-dwelling older adults. METHODS: We examined 2 963 adults aged ≥60 and older from the Seniors-ENRICA cohort. At baseline (2008-2010) and subsequent follow-up (2012), zinc intake (mg/d) was estimated with a validated computerized face-to-face diet history and adjusted for total energy intake. From 2012 to 2017, the occurrence of ILEF was ascertained with the Short Physical Performance Battery, and of frailty according to the Fried phenotype criteria. Analyses were conducted using Cox proportional hazard models adjusted for relevant confounders, including lifestyle, comorbidity, and dietary factors. RESULTS: During follow-up, we identified 515 incident cases of ILEF and 241 of frailty. Compared with participants in the lowest tertile of zinc intake (3.99-8.36 mg/d), those in the highest tertile (9.51-21.2 mg/d) had a lower risk of ILEF (fully adjusted hazard ratio [95% confidence interval]: 0.75 [0.58-0.97]; p for trend: .03] and of frailty (0.63 [0.44-0.92]; p for trend: .02). No differences in the association were seen by strata of sociodemographic and lifestyle factors. CONCLUSIONS: Higher zinc intake was prospectively associated with a lower risk of ILEF and frailty among older adults, suggesting that adequate zinc intake, which can be achieved through a healthy diet, may help preserve physical function and reduce the progression to frailty.

Plasma Amino Acids and Risk of Impaired Lower-Extremity Function and Role of Dietary Intake: A Nested Case-Control Study in Older Adults.

INTRODUCTION: Amino acids are key elements in the regulation of the aging process which entails a progressive loss of muscle mass. The health effects of plasma amino acids can be influenced by dietary intake. This study assessed the prospective association between amino acid species and impaired lower-extremity function (ILEF) in older adults, exploring the role of diet on this association. METHODS: This is a case-control design comprising 43 incident cases of ILEF and 85 age- and sex-matched controls. Plasma concentrations of 20 amino acid species were measured at baseline using liquid chromatography-tandem mass spectrometry, and incident cases of ILEF were measured after 2 years by means of the Short Physical Performance Battery. Conditional logistic regression models were used to assess longitudinal relationships. RESULTS: After adjusting for potential confounders, higher levels of tryptophan were associated with a decreased 2-year risk of ILEF (OR per 1-SD increase = 0.64, 95% CI = [0.42, 0.97]), while glutamine and total essential amino acids were linked to higher ILEF risk (OR = 1.57, 95% CI = [1.01, 2.45]; OR = 1.89, 95% CI = [1.18, 3.03], respectively). Those with a lower adherence to a Mediterranean diet, a higher BMI, a higher consumption of red meat, and a lower consumption of nuts and legumes had an increased risk of ILEF associated with higher levels of essential amino acids. DISCUSSION/CONCLUSION: Some amino acid species could serve as risk markers for physical function decline in older adults, and healthy diet might attenuate the excess risk of ILEF linked to essential amino acids.