Is there a condition called diastolic hypertension? what is it and how does it relate to chronic kidney disease (ckd)?

Diastolic is the second reading of a BP,.eg.120/80, the 80 is the diastolic reading. Diastolic reading is important in high BP. HBP eventually affects kidney function if not controlled.

Yes, isolated diastolic hypertension is common in patient with chronic kidney disease, especially in young cohort. Diastolic pressure between 81-90 is borderline, above 90 is high. Give example: blood pressure of 139/91 or 130/100 will be called diastolic hypertension.