The Relationship Between Muscle Attenuation And Orthostatic Blood Pressure Variations In Elderly Population

ObjectivesTo access the strength,function and mass of muscles,and evaluate the muscle attenuation status,as well as analyze the relationship between muscle attenuation status and orthostatic blood pressure variations in elderly population.Methods929 subjects over the age of 60 were selected from Fujian Provincial Hospital in the period between September 2015 to December 2016.All subjects underwent basic data collection,physical examination,laboratory examination and orthostatic blood pressure measurement.The muscle attenuation status assessment including the assessment of the strength,function and mass of muscles,which were evaluated by grip strength,4 meters pace and relative appendicular skeletal muscle index(RASMI).The trend test analysis was applied to explore the relationship between the strength,function,mass of muscles and age,body mass index(BMI),and pulse pressure.The binary logistic regression analysis was used to explore the relationship between muscle strength,muscle function and orthostatic hypotension(OH).The multiple linear regression analysis was performed to explore the relationship between muscle strength,muscle function and orthostatic blood pressure variations.Results1.The grip strength in the male and female groups were 30.5±8.0kg and19.2±4.9kg,and the RASMI in those groups were 7.20±1.00kg/m2 and 5.82±0.85kg/m2 respectively.The 4 meters pace in this population was 0.93±0.28m/s.The decline of muscle strength,muscle function and muscle mass accounted for 58.6%,55.4% and52.3% repectively.Combined with the muscle strength decline and muscle dysfunction accounted for 46.3%.The prevalence of muscle attenuation was 39.9%.2.Combined with the muscle strength decline and muscle dysfunction exhibited a trend to increase with the increase of age and pulse pressure(all P < 0.01).Theproportion of muscle strength decline with muscle dysfunction was significantly lower in the dyslipidemia group than that in the normal blood lipid group,and which was higher in the coronary heart disease group than that in the non-coronary heart disease group(all P<0.05).3.The muscle strength and function in the OH group were worse than those in the non-OH group(P<0.05).The risk of developing OH decreased with the increase of grip strength within the tertiles(OR:0.663,95%CI:0.537~0.819)and also with the increasing pace(OR:0.224,95%CI:0.066~0.769).Compared with the normal muscle strength and muscle function group,the normal muscle strength with declined muscle function group(OR:1.448,95%CI:0.389~5.396),the declined muscle strength with normal muscle function group(OR:2.840,95%CI:1.040~7.754),and the declined muscle strength with muscle dyfunction group(OR:4.945,95%CI:1.975~12.384)all have greater risk of OH(all P<0.05).There were interactions between muscle strength and muscle function(P<0.01).4.Multiple linear regression analysis showed that the variations of systolic blood pressure(SBP)in 1 min were negatively correlated with male and female muscle strength? muscle function as well as the strength and function levels of muscles(?=?0.305??0.378??8.172??3.714,all P<0.05);The variations of diastolic blood pressure(DBP)in 1 min were negatively correlated with male muscle strength?muscle function as well as the strength and function levels of muscles(?=?0.149??3.672??1.180,all P<0.05);The variations of DBP in 3 min were negatively correlated with the strength and function levels of muscles(?=?0.799,P<0.05);The SBP coefficient of variation was negatively correlated with the male muscle strength and the strength and function levels of muscles(?=?0.097?-0.776,all P<0.05).ConclusionsThe prevalence of muscle attenuation was 39.9% in this population.The orthostatic blood pressure variations and the risk of OH increased in the subjects with declined muscle strength and muscle dysfunction.Improving muscle attenuation status may reduce the occurance of OH in the elderly population.