Brief Answer:
Single reading not to be considered significant

Detailed Answer:
Dear XXXXX,

Thanks for your query.

A reading of systolic blood pressure below 90 mm of Hg & diastolic blood pressure below 60 mm of Hg is considered to be low (Hypotension).

In your post, you have not mentioned about the reading of systolic blood pressure.
Assuming that the systolic blood pressure is within normal limits, a solitary reduction in diastolic blood pressure can be attributed to decreased peripheral resistance of the arteries, which is seen in old age due to loss of elasticity of the arteries.

However, it should be remembered that individual's blood pressure varies with age, exercise, emotional reactions, sleep, digestion, endocrine factors, hydration status of body, time of day, circadian rhythm, etc.

Keeping in view the above mentioned fact, a single reading of diastolic pressure of 56 mm of Hg is not considered of any significant value.
Low blood pressure is only a concern when it is associated with symptoms such as lightheadedness, disturbance in vision, loss of consciousness, shortness of breath, or poor exercise tolerance.
And you have mentioned any such symptoms in your post.

So, kindly get your blood pressured measured once again, preferably 2 readings, taken 5 minutes apart in sitting position (as per the guidelines of JNC 7).

Hope I have been able to answer your query.
If you have additional questions or follow up queries then please do not hesitate in writing to us.
I will be happy to answer them.
Take care.

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