Photobiomodulation therapy for the prevention of chemotherapy-induced peripheral neuropathy (NEUROLASER trial)

Abstract

Background and aims: Orthostatic hypotension (OH) and supine hypertension (SH) are prevalent in alpha-synucleinopathies, posing a therapeutic dilemma as OH treatment may worsen SH. We aimed to characterise SH using autonomic testing and 24hr-ambulatory blood pressure monitoring (24hr-ABPM), effects of pharmacological OH treatment in pure autonomic failure (PAF), multiple system atrophy (MSA), and Lewy body disorders (LBD: Parkinson's disease and Dementia with Lewy bodies). Methods: 166 patients (72 PAF, 59 MSA, 35 LBD) underwent cardiovascular autonomic testing and 24hr-ABPM. Demographic and clinical features, medications and cardiovascular autonomic biomarkers were compared. Results: 51% (84/166) of patients were on anti-hypotensive medications. SH and OH commonly co-existed in patients with PAF, MSA and LBD, both with anti-hypotensive medications (75%, 63% and 60%, respectively) and without (56%, 51% and 50%, respectively). Supine pre-stand BP during 24hr-ABPM detected SH with 60% sensitivity and 86% specificity (area under the curve 0.73 (95%CI 0.66-0.81). 74% (61/82) of patients without anti-hypotensive medications had nocturnal hypertension. Mean supine and nocturnal BP was higher in patients with anti-hypotensive medications (p<0.05). Supine noradrenaline levels were significantly higher in MSA vs PAF and LBD (268 vs 183 and 210 pg/ml, p<0.01). There was a strong correlation between OH, SH and nocturnal hypertension after adjusting for age, gender, anti-hypotensive medications and supine noradrenaline levels (R2=0.48, p<0.01). Conclusion: SH and nocturnal hypertension commonly co-exist and are independently associated with OH in alpha-synucleinopathies. 24hr-ABPM is useful in detecting SH in autonomic failure patients. The pathophysiology of SH is likely to be heterogeneous and not entirely explained by residual sympathetic tone.