Association Between Geriatric Nutrition Risk Index And Bone Mineral Density In Elderly Chinese People

BackgroundOsteoporosis(OP)is a growing major public health problem.Patients usually experience osteopenia,OP,and OP-related complications,resulting in decreases in their quality and quantity of life,crossing medical,social,and economic lines.The main mechanism of OP is the loss of bone mass.Thus,to maintain quality of life,it is necessary to reduce the risk of OP-related complications such as fractures.Some studies have shown that malnutrition contributes to the occurrence of OP by lowering bone mass and altering muscle strength.Furthermore,the rate of medical complications after fracture can also be increased by nutritional deficiency.There are currently several tools and indicators to assess nutritional condition,such as the Mini Nutritional Assessment(MNA),Nutritional Risk Index(NRI),ratio of actual weight to standard weight,body adiposity index(BAI),body mass index(BMI),grip strength,visceral albumin,and nitrogen balance.However,these indices remain limited for elderly patients.Recently,the geriatric nutritional risk index(GNRI)has been put forward for prediction of nutrition-related risk of complications in the elderly.Some studies have indicated that GNRI is associated with heart failure,chronic kidney disease,and mortality,and can predict muscle dysfunction and nutritional-related complications in hospitalized elderly patients.However,the association between GNRI and bone mineral density(BMD)has not been adequately investigated.For instance,it is still not known whether GNRI has any significant value as an indicator of OP or low bone mass.Thus,we aimed to investigate whether GNRI might be a reliable detector of bone mass loss in the elderly,identifying older people suitable for a further bone health approach.Objectives1.To evaluate the nutritional status of the elderly using GNRI values.2.To investigate the relationship between GNRI and bone mineral density(BMD)in Chinese elderly population.3.To elaborate the application value of GNRI in elderly patients with osteoporosis,and to provide more theoretical basis for further nutritional intervention to reduce the risk of osteoporosis and osteoporosis related complications.Method1.Calculate the sample size.The sample size of this study was calculated using the following formula:n=400 X {(1-M)/M}(M is the known prevalence of the disease).2.All participants were selected from the Fifth Affiliated Hospital of Sun Yat-sen University from May 2018 to December 2019.There were 1130 elderly people aged 60-89,including 713 males and 417 females,with an average age of 70.3 years.3.All participants underwent clinical,laboratory,and densitometry examination.Bone mineral density was measured by dual energy X-ray bone densitometer and corresponding software.4.Differences between study groups were assessed using independent-samples t-test,one-way analysis of variance(ANOVA)for continuous variables and the chi-square test for categorical variables.Pearson’s correlation coefficient was used to evaluate the correlation between the two variables.Multiple linear regression analysis was used to explore the possible variables affecting bone mineral density.Results1.The mean age of the participants in the study was 70.3 years(range 60-89),and 63.2%of the individuals were male.The mean BMD of total hip and lumbar spine was-0.48 ± 0.98 and-1.10± 1.58 in men,-0.84 ± 1.04 and-2.64 ± 1.29 in women.The incidences of bone unhealthy were 61.34%in men and 91.13%in women.The participants with lower bone mass had lower GNRIs than controls significantly(t=-3.753,P<0.001 in men,t=-2.793,P=0.005 in women,respectively).2.Compared to the participants in tertile 1,individuals in tertile 3 were significantly younger and had a lower prevalence of male gender,smoking history,and pulmonary disorder,higher levels of BMI,total hip T-score,lumbar spine T-score and a higher prevalence of hypertension,diabetes,and hyperlipemia,as well as higher levels of white blood cells,lymphocytes,hemoglobin,serum total protein,albumin,glutamase,total cholesterol,triglycerides,LDL lipoprotein.3.In young adults(aged 60-79),GNRI is closely related to femur and hip bone mineral density,especially in female,meanwhile,in the elderly(aged 80-89),GNRI is related to bone mineral density at each site.4.Pearson’s correlation demonstrated that GNRIs were positively correlated with BMD in both sexes at different anatomical sites.However,correlation between GNRI and BMD of L4 was not significant in the overall values(P=0.058).5.A multiple regression demonstrated that GNRIs were associated independently with Proximal Femur T-score in both sexes(β=0.111 for men and 0.174 for women,P=0.034,0.008,respectively].However,the correlation was not significant in the lumbar spine.Conclusion1.The correlation between nutritional status and bone mineral density in older female was more obvious than in male.2.Malnutrition mainly affects the bone mineral density at the hip and proximal femur,meanwhile affects less on the lumbar spine.3.GNRI serves as a reliable screening tool for assessing bone health in older elderly.