Delivering tertiary centre specialty care to ALS patients via telemedicine: a retrospective cohort analysis.

OBJECTIVE: This study was undertaken to determine if ALS patients evaluated via telemedicine received the same quality of care as patients evaluated by traditional face-to-face encounters. METHODS: A retrospective cohort study design was used. Participants were patients diagnosed with ALS that received multidisciplinary care at the tertiary Cleveland VA ALS Centre between 1 March 2008- and 31 anuary 2015. Participants were not randomised, but chose telemedicine based on preference, disability level or distance from the clinic. Telemedicine in this study consisted of a video conferencing platform enabling remote rather than face-to-face encounters with participants. RESULTS: There was no significant association between receiving quality ALS care and the mode of care. There was a trend for telemedicine patients to utilise home health care less often than those that received clinic care (AOR 0.50; 95% CI 0.16-1.59). There was no significant difference in survival time between the two groups (log-rank test χ2 = 3.62, df = 1, p = 0.05). Patients receiving telemedicine had a higher probability of remaining stable or having <30% decrease in ALSFRS-R over time (log-rank test χ2 = 4.46, df = 1, p = 0.03). There was a significantly lower risk of disease progression for patients receiving telemedicine (HR = 0.39, 95% CI = 0.16-0.93). CONCLUSIONS: Patients managed by telemedicine received the same quality of care and had similar outcomes to those patients seen via traditional face-to-face encounters. Telemedicine is an effective platform for delivering high quality tertiary ALS care.

Large neutral amino acids levels in primate cerebrospinal fluid do not confirm competitive transport under baseline conditions.

In rodents, transport of large neutral amino acids (LNAAs) across the blood brain barrier (BBB) and blood-cerebrospinal fluid (CSF) barrier is mediated by high affinity carriers. Net brain LNAA levels are thought to be determined mainly by this competitive transport from plasma. Since the affinity for LNAA transport at the BBB in primates is considerably higher than in rodents, brain influx and by extension LNAA brain levels, should be even more dependent on competitive transport. Given that LNAA levels in CSF and brain interstitial fluid are usually similar, we analyzed serum and CSF of fasted subjects (n=24) undergoing spinal anesthesia and calculated brain influx and transporter occupancy using a conventional model of transport. Despite predicted near-full transporter saturation (99.7%), correlations between CSF levels and brain influx were modest, limited to tyrosine (r=0.60, p<0.002) and tryptophan (r=0.50, p<0.01) and comparable to correlations between CSF and serum levels. We also analyzed serum and CSF in (n=5) fasted vervet monkeys. Tyrosine and phenylalanine levels in CSF were positively correlated with those in serum, but correlations with calculated brain influx, which takes competition into account, were weaker or absent. We conclude that in primates i) baseline CSF LNAA levels do not confirm competitive transport, ii) brain LNAA levels should not be estimated on the basis of serum indices alone. This has implications for amino acid challenge studies and for neuropsychiatric disorders associated with dysregulated LNAA transport in which quantitative information about brain LNAA levels is needed.