Nondipping blood pressure linked to poor sleep
medwireNews: A nondipping blood pressure pattern - in which blood pressure fails to fall by at least 10% during sleep - is associated with poor sleep quality, a study by Turkish researchers has found.
Intriguingly this association was present in both hypertensive and normotensive individuals, a finding with implications for the investigation of patients with poor sleep quality.
"When evaluating patients with poor sleep quality, the fact that they may have a nondipping pattern, even if they may be normotensive, should be kept in mind," write Sena Ulu (Afyon Kocatepe University, Afyonkarahisar, Turkey) and co-authors in Blood Pressure Monitoring.
Ulu's team prospectively recruited 100 patients with normal blood pressure, as determined by ambulatory blood pressure monitoring. Of these, 50 had a normal nighttime dipping pattern while 50 were "nondippers," which is a known risk factor for cardiovascular disease.
All patients were evaluated for sleep disturbances using the Pittsburgh Sleep Quality Index (PSQI) questionnaire. The mean score on the PSQI was 4.7 in dippers versus 6.8 in nondippers, a statistically significant difference.
Noting that PSQI scores of 5 or more indicate worse sleep quality, the researchers report that 62% of the nondipper group had poor sleep quality versus just 40% of the dipper group, again a significant difference.
Further analysis showed that nondippers scored significantly worse than dippers on multiple domains of sleep quality, including sleep duration, sleep latency, sleep efficiency, use of sleep medication, sleep disturbance, sleep quality, and daytime dysfunction.
In multiple linear regression analysis, dipping status was significantly associated with PSQI scores, after adjusting for age.
The researchers conclude: "A nondipping pattern appeared to be associated with poor sleep quality not only in hypertensive patients but also in normotensive healthy individuals…. Further studies with a larger number of patients are required to explore these associations."
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By Joanna Lyford, Senior medwireNews Reporter