Classify blood pressure based on systolic (SBP) and diastolic (DBP)
Published:
A simple implementation of classifying blood pressure into different categories, namely normal,prehypertension,stage1 hyptertension and stage2 hypertension in both Matlab and Python
AAMI blood pressure
According several authorized blood pressure organizations, such as AAMI (American Heart Institution), blood pressure can be categoried into different classes based on the ranges of systolic and diastolic blood pressure readings, as shown in the table below. 
Implementation
Matlab code:
function bp_level = bp_classification(dbp,sbp)
% input are dbp and sbp readings, e.g., dbp=76, sbp=128 in mmHg
% output: bp_level ([1,2,3,4]), 1: normal, 2: prehypertension, 3: stahe1 hypyertension, 4: stage2 hypertension
if dbp<80 && sbp<120 % normal BP range
bp_level = 1;
elseif (dbp>=80 && dbp<90) && sbp<120 % prehypertension
bp_level = 2;
elseif (sbp>=120 && sbp<140) && dbp<80 % prehypertension
bp_level = 2;
elseif (sbp>=120 && sbp<140) && (dbp>=80 && dbp<90) % prehypertension
bp_level = 2;
elseif (dbp>=90 && dbp<100) && sbp<140 % stage1 hypertension
bp_level = 3;
elseif (sbp>=140 && sbp<160) && dbp<90 % stage1 hypertension
bp_level = 3;
elseif (sbp>=140 && sbp<160) && (dbp>=90 && dbp<100) % stage1 hypertension
bp_level = 3;
elseif sbp>=160 || dbp>=100 % stage2 hypertension
bp_level = 4;
end
end