116 



308 J. A. MACWILLIAM 



Addis (1) examined nearly 400 subjects in two categories, the pres- 

 sures being taken in the recumbent posture^ — ^1, under basal conditions; 

 systolic average 99, diastolic 71. 2, Under other conditions, food taken, 

 walking, etc., systolic average 127, diastolic 78. 



The relation of hlood 'pressures to age. There is general agreement as 

 to the presence of lower systolic and diastolic pressures in childhood, 

 the differences from the adult being more marked in the systolic levels 

 with a consequent diminution of the pulse pressures. 



The work of Judson and Nicholson (71), Melvin and Murray, and 

 Faber and James (44) may be referred to, also the more recent obser- 

 vations of Stocks and Karn (120). In connection with the smaller 

 pulse pressures the quicker pulse rate of children has to be taken into 

 account, tending to make the product of P.R. X P.P. approximate to 

 what holds good in the adult. 



The available evidence shows that from the very early phase of life 

 there is a progressive steady rise of pressure, apparently a function of 

 increasing age, up to the onset of puberty, then an acceleration of the 

 rise up to the ages of 17 to 20. It is to be noted that there are decided 

 differences between the results of Judson and Nicholson and of Faber 

 and James on American boys, and those of Stocks and Karn on British 

 boys, as regards the actual values of the pressures recorded and the 

 extent of the rise between the ages of 5 and 14 years. At the former 

 age the American observers found systolic averages of 92 mm. and 93 

 mm. respectively; at the latter age 106 mm. and 110 mm. On the 

 other hand Stocks and Karn report a lower average, 85 mm., at age 

 5 and a higher level, 115 mm. at age 14 — a rise of 30 mm. which is 

 nearly twice that found by the other observers. The accelerated rise 

 during puberty and adolescence between the ages of 13 and 17 has been 

 found by Stocks and Karn to amount to 16 mm. 



Woley (134) dealing with systolic pressures in 1000 apparently 

 healthy subjects, found an average level in males of all ages of 127.5 

 mm., in females of 120 mm., and a rise from 122 mm. in the age group 

 15 to 30 years to 132 mm. in the 50 to 60 age group. He distinguished 

 a high pressure group with an average pressure of 141 mm. at the ages 

 15 to 30 to 149 mm. at 50 to 60, and a low pressure group rising from 

 an average of 103 mm. in the 15 to 30 group to 115 mm. in the 50 to 

 60 category. At the intermediate ages averages of intermediate value 

 were obtained, a gradual rise occurring with increasing age and a cor- 

 responding rise in high and low averages. He regarded a pressure of 

 144 mm. in the 50 to 60 age group as being definitely acceptable for 



