Association Of Dietary Factors With The Risk Of Sarcopenia And The Effect Of Muscle Mass On Cardio-metabolic Risk Factors

Objective:With the advent of an aging society,the prevalence of sarcopenia in the elderly has been increasing year by year in China.It has become one of the important diseases threatening the quality of life of Chinese residents.The prevention and treatment of sarcopenia has become an increasingly prominent public health problem.Based on the community health examination in Qingdao,this study systematically analyzed the relationship between dietary nutrient intake and the risk of sarcopenia among residents over 65 years old.Since muscles are distributed in different parts and may have differentiated physiological functions,we further explore the relationship between local muscle mass index and cardiovascular metabolic risk factors and clarify the impact of regional muscle mass on cardiovascular disease.Methods:A total of 1,140 participants(72.7 ± 6.3 years old)were recruited through an annual health check-up program in Qingdao,China.The skeletal muscle mass of the participants was measured by bioelectrical impedance analysis(BIA).The muscle strength was measured by hand-held grip dynamometer,and 6-meter walking speed was used to measure muscle function.The cardio-metabolic risk factors were defined according to the Guidelines for Prevention and Treatment of Dyslipidemia in China Adults and China’s Guideline for Prevention and Treatment of Type 2 Diabetes.The dietary intakes of nutrients were assessed by a 3-day,24-hour dietary recalls.The data in the 3-day 24-hour dietary recalls were calculated by the computer expert system of integrated traditional Chinese and Western medicine nutrition treatment(NCCW version 12.0).The odds ratio(OR)and 95%confidence interval(CI)of the risk of sarcopenia for quartiles of dietary nutrient intake was calculated using multivariable-adjusted logistic regression models.Generalized linear models were used to analyze the association of dietary nutrient intake with muscle strength and function.Associations between wholebody and local muscle mass indices and cardiovascular risk factors were calculated based on multivariate adjusted logistic regression models and Pearson’s partial correlation coefficients.Results:The prevalence of sarcopenia was 4.1%.After adjusting for potential confounding factors,compared with the lowest quartile,the highest quartile intakes of branched chain amino acids(BCAAs)(OR=0.11;95%CI:0.01,0.90;p for trend=0.119),isoleucine(OR=0.11;95%CI:0.01,0.89;p for trend=0.122)and tryptophan(OR=0.10;95%CI:0.01,0.87;p for trend=0.176)were negatively associated with the risk of sarcopenia.GLM analysis showed that grip strength was significantly and positively correlated with elemental sodium intake(p=0.006),and step speed was significantly and positively correlated with intake of lysine,threonine,leucine,valine,tryptophan,BCAAs,aromatic amino acids,vitamin B2,vitamin C,and elements of potassium,calcium,phosphorus,and selenium(p<0.05)with adjustment for potential confounders.After adjusting for potential confounding factors,the highest quartile of leg muscle mass index(LMMI)was negatively associated with risk of central obesity(OR=0.08;95%CI:0.04,0.14;p for trend<0.001),risk of hypertension(OR=0.45;95%CI:0.27,0.75;p for trend=0.001)and risk of hypertriglyceridemia(OR=0.49;95%CI:0.30,0.80;p for trend=0.028),and positively associated with risk of hypercholesterolemia(p<0.05).Compared with the lowest quartile,the highest quartile of trunk muscle mass index(TMMI)was negatively associated with the risk of central obesity(OR=0.06;95%CI:0.03,0.11;p for trend<0.001)and hypertension(OR=0.59;95%CI:0.37,0.96;p for trend=0.035),and positively associated with the risk of hypercholesterolemia(p<0.05).In addition,LMMI and TMMI in the third quartile were significantly associated with a reduced risk of hyperglycemia(p<0.05).Dose-response analysis indicated that one standard deviation increment of LMMI was associated with a 51%,23%and 27%reduction in central obesity,hypertension,and hypertriglyceridemia,respectively.Conclusion:The results of the present study demonstrated that higher dietary intakes of BCAAs were negatively associated with the risk of sarcopenia.Appropriate protein intake(60.9-74.3 g/d)had beneficial effects to prevent sarcopenia and improve physical function in the elderly.In addition,increases in lower leg mass and trunk muscle mass were significantly negatively correlated with cardio-metabolic risk factors in the elderly to reduce cardiovascular metabolic diseases.The findings of the present study will have public health significance for the prevention of sarcopenia and cardiovascular diseases in China.