Modifying effect of arterial hypertension on amyotrophic lateral sclerosis

Abstract

Given the high oxygen consumption of motor neurons, we sought to assess the frequency and prognostic value of arterial hypertension (affecting brain's oxygen supply) in amyotrophic lateral sclerosis (ALS). We consecutively and prospectively included all ALS patients with regular medical follow-up and documented blood pressure measurements and monitored them until death. Vascular factors diagnosed prior to the onset of motor signs in ALS patients were compared with those in a stratified, age- and gender-matched case-control population. The severity of leukoaraiosis on magnetic resonance imaging (MRI) was blindly assessed. Post mortem examinations were performed when authorized. Compared with controls (n = 408), the 102 ALS patients were significantly more likely to display hypertension (41–57%) and current smoking (15–26%). The number of years of hypertension was associated with survival (HR = 1.04 (1.01–1.07)). In a multivariate analysis, leukoaraiosis severity (HR = 1.214 (1.096–1.344)), current smoking (HR = 1.766 (1.085–2.872)) and low vital capacity (HR = 2.422 (1.266–4.633)) remained independent predictors of survival. Post mortem examinations revealed a greater frequency of leukoaraiosis in ALS patients (p = 0.02). In conclusion, the effect of chronic hypertension on survival might be exerted through abnormal neural perfusion. The higher frequency of recent hypertension in ALS patients may be due to a compensatory increase in blood pressure in response to a lower oxygen supply.

Key words::

• ALS
• arterial hypertension
• vascular factor
• epidemiology
• prognosis

Acknowledgements

This study was funded by the ARSla charity and by PHRC grants from the French Ministry of Health. The authors wish to thank the Fédération de la Recherche Clinique du CHU de Lille (Lille University Hospital) for promoting the study, David Fraser (Biotech Communication, Damery, France) for oversight of the English translation, Christelle Monaca for her expertise in sleep disorders, Charlotte Cordonnier for her expertise in neurovascular disorders and Claude Alain Maurage for his expertise in neuropathology.

Jean Dallongeville and Philippe Amouyel are funded by grants from the French government. Régis Bordet is funded by grants from the French government, and he has received various honoraria for lectures at symposia sponsored by pharmaceutical companies. Luc Defebvre has served on scientific advisory boards for Novartis and Aguettant. He has received various honoraria for lectures on Parkinson's disease at symposia sponsored by pharmaceutical companies. Alain Destée served on a scientific advisory board for Novartis and has received research funding (PHRC grants) from the French Ministry of Health. He has received various honoraria for lectures on Parkinson's disease at symposia sponsored by pharmaceutical companies. David Devos has served on scientific advisory boards for Novartis and Aguettant, is funded by PHRC grants from the French Ministry of Health and has received research funding from the ARSla charity. He has received various honoraria for lectures on Parkinson's disease at symposia sponsored by pharmaceutical companies.

Declaration of interest: The authors have no financial disclosures to make or potential conflicts of interest to report in relation with this study. The authors alone are responsible for the content and writing of the paper.