The "nondipper" elderly: a clinical entity or a bias?

Abstract

To determine the prevalence of nondipper (ND) blood pressure profile in the elderly and to ascertain whether the ND pattern of ambulatory blood pressure in the elderly is an artifact or represents a specific clinical entity. Cross-sectional, observational study. Cardiovascular diagnostic center, division of geriatrics, secondary care, institutional practice. Sixty-five consecutive community-dwelling elderly hypertensive patients referred to the cardiovascular center. The patients underwent actigraphy and ambulatory blood pressure monitoring and completed a sleep assessment questionnaire. Patients were divided based on the night-time decrease in blood pressure (>10%: "dippers" (n=19); <10%: "NDs" (n=46)). Nondippers displayed poorer quality of sleep, as demonstrated objectively by actigraphic data; they obtained a higher mean score+/-standard deviation on the sleep questionnaire (4.6+/-2.9 vs 3.0+/-1.1, P=.030) and were taking more benzodiazepines (33.1% vs 10.7%, P=.035), indicating that their usual sleep quality was worse than that of dippers. Multivariate analysis showed a strong correlation between nondipper profile and quality of sleep and also with comorbidity, total number of drugs being taken, and pulse pressure. Actigraphy demonstrates impaired sleep in the nondipper elderly. Nevertheless, the nondipping pattern seems independent of the discomfort of cuff-inflation during the night and occurs in association with higher comorbidity and polypharmacy; therefore, it cannot be considered a "bias," but is related to detrimental clinical conditions that should be studied in depth.