Previous research suggests that daytime BP values are lower in hot months than in cold months. In a recent study, however, warmer nighttime air temperatures were linked to higher BPs at night in those over age 65 taking medicines to lower BP.

Based on the new findings, investigators from Florence, Italy, suggest that older patients not reduce their drug dosage—even if daytime BP measurements during the summer months are within normal range.

The unexpected association was not detected among younger participants. The researchers recommend the use of 24-hour ambulatory BP monitoring to assess treatment effects in older patients.