Reverse blood pressure (BP) dipping during sleep, or nocturnal BP that increases during sleep, is predictive of cardiovascular dysautonomia in patients with Parkinson disease (PD), according to a study published in Parkinsonism and Related Disorders. The researchers suggest patients with PD be screened for reverse nocturnal BP dipping because of the ease and affordability of the screening.
Consecutive patients with idiopathic PD (mean age, 64±10 years; disease duration, 6±4 years) who were receiving care at a movements disorder clinic in Italy were enrolled in the cross-sectional analysis (n=114). Same-day autonomic testing as well as 24-hour ambulatory BP monitoring were performed in all patients. The investigators assessed the association between abnormal nocturnal BP dipping (ie, reverse dipping) and cardiovascular dysautonomia, which was defined as the presence of ≥1 moderate or severe abnormality on a cardiovagal and adrenergic test.
The rate of cardiovascular dysautonomia was approximately 32%. A greater proportion of patients with dysautonomia had supine hypertension compared with patients without dysautonomia (50% vs 22%, respectively). Significantly higher bedside supine BP values were observed in those with vs without nonneurogenic orthostatic hypotension (139±16/82±7 vs 126±13/76±8 mm Hg; P <.001).
In addition, a significantly greater proportion of patients with cardiovascular dysautonomia had reverse dipping (69% vs 15%; P <.001). Reverse dipping featured higher diagnostic accuracy for identifying cardiovascular dysautonomia (area under the curve, 0.791; specificity, 84%; sensitivity, 69%) compared with bedside BP ascertainment of neurogenic orthostatic hypotension (0.681; specificity, 66%; sensitivity, 69%) and supine hypertension (0.641; specificity, 78%; sensitivity, 50%).
Limitations of the study were inclusion of patients receiving BP-interfering medications, as well as the use of a relatively subpar cutoff value definition of orthostatic hypotension.
Findings from the analysis validate “the alterations in circadian BP rhythm in PD and supports the ascertainment of reverse dipping as marker of cardiovascular dysautonomia.”
Milazzo V, Di Stefano C, Vallelonga F, et al. Reverse blood pressure dipping as marker of dysautonomia in Parkinson disease [published online June 28, 2018]. Parkinsonism Relat Disord. doi: 10.1016/j.parkreldis.2018.06.032