Effect of fasting on 24-h blood pressure values of individuals with no previous history of hypertension.

OBJECTIVE: We aimed to analyze the difference in 24-h blood pressure values during Ramadan of fasting and nonfasting individuals with no previous history of hypertension.

PATIENTS AND METHODS: This study was planned as a multicenter research study in the cities of Izmit, Zonguldak, Sivas, and Adana. The percentage changes in the blood pressure of the patients were calculated from their blood pressure measurements at 0 h while they were resting. A Food Frequency Questionnaire was filled out by all participants.

RESULTS: Forty patients were included in the fasting group and 55 patients were included in the nonfasting group in the study. There was a difference between the two groups in percent changes of systolic measurements performed at the 4th (5% difference and P=0.020), 13th (6% difference and P=0.015), 14th (10% difference and P=0.017), 18th (9% difference and P=0.027), 19th (9% difference and P=0.020), and 20th (6% difference and P=0.014) hours with respect to the baseline measurement at the 0 h. There was a difference between the fasting and nonfasting groups in the Fasting Food Questionnaire results. Meat consumption was significantly higher in the fasting group.

CONCLUSION: A systolic blood pressure increase in fasting patients was observed in measurements at 18:00, 19:00, and 20:00 h. We believe that an increase of more than 10% in blood pressure at the time of iftar is an important result of our study in terms of the meal preferences of the individuals under risk.