The calc’s reported risk also doesn’t have a simple linear relationship with blood pressure. Changing some of the variables, I noted that my risk level decreases if I increase my blood pressure up to 120. Increasing my blood pressure reduces my reported cardiovascular risk.
I expect this relates to not being well represented by the persons used to complete the population based stats in the calc outputs. My workout intensity/frequency is quite high and has contributed to having a resting heart rate in the low 40s. This type of low resting heart is not uncommon among endurance athletes, and my other cardiovascular stats like VO2Max are well aligned with being an athlete, rather than having a medical problem. Endurance athletes with low HR, high VO2Max, … average lower blood pressure than population norms. When the heart doesn’t need to work as hard, there is often less pressure on walls.
However, I expect population based studies used to generate calc outputs find that rather than being an athlete, it is more likely that significantly less than 120 systolic blood pressure is a sign of a medical problem and can lead to heart need to work harder or beat faster to compensate for the low pressure, as well as other factors that increase cardiovascular risk.