Data showing how Repeated Lumbar Punctures within 3 days may affect CSF Biomarker Levels

As an extension of a study on the relationship between sleep deprivation and cerebrospinal fluid (CSF) biomarkers for Alzheimer’s disease, we performed two Lumbar punctures (LPs) within three days in 13 healthy volunteers (N=13). Our aim was to investigate CSF biomarker dynamics in relation to sleep deprivation. An unexpected sharp rise in biomarker concentrations in the second sample made us consider an artifact and we therefore repeated the experiment, but without sleep restriction, in four additional individuals (N=4). A similar rise in biomarker levels were evident, suggesting an inherent methodological problem with repeated LPs.

Experiment 1: Repeated lumbar punctures within 3 days without sleep intervention.
Participants with controled normal sleep. Biomarker concentrations from each individual lumbar puncture.

Experiment 2: After sleep deprivation and 3 days later, after recovery sleep.
Biomarker concentrations from each individual lumbar puncture. First puncture immediately after sleep deprivation. Second puncture three days later, after recovery sleep.