To report changes in sleep metrics in patients with relapsing multiple sclerosis (MS) who underwent a 6-month ketogenic diet (KD) intervention.

Dietary intake influences the immune profile and response. The impact of diet in MS is clinically meaningful, with evidence supporting an association between diet and disability. Our prior data supports the tolerability and potential clinical benefits of a modified Atkins ketogenic diet (KD^MAD) in patients with relapsing MS. Sleep disturbance in patients with MS is common and frequently disabling, thus interventions to improve sleep would be highly impactful. KDs have been associated with improved sleep quality in epilepsy, but the impact in patients with MS remains unexplored.

Forty-five adult patients with relapsing MS were enrolled into a 6-month KD^MAD intervention. Diet adherence was monitored by daily urine ketone testing. Daytime sleepiness was assessed at baseline (pre-diet) and after 6 months of diet treatment with the Epworth Sleepiness Scale (ESS) and the Sleep Disorders Symptom Checklist-25 (SDS-CL-25). The ESS is validated to evaluate average sleep propensity as a marker of disordered sleep. The SDS-CL-25 is a screening tool for several sleep disorders, including insomnia and obstructive sleep apnea (OSA).

Thirty-nine of the 45 subjects completed the full 6-month KD intervention - including pre- and post-diet ESS assessments, while 36 subjects completed both SDS-CL-25 assessments. There was a mean decrease in ESS score from baseline to 6 months of 1.90 ± 3.0 (p<0.001). The relative frequency of excessive daytime sleepiness (ESS score>10) was reduced at 6 months on-diet (15.4% vs 7.7%; p=0.001). There were reductions in SDS-CL-25 total score (-3.6 ± 7.7; p=0.008), mean insomnia score (-1.5 ± 3.5; p=0.013), and mean OSA score (-0.8 ± 0.36; p=0.014).

The KD^MAD intervention leads to improvements in daytime sleepiness and sleep disorder symptoms in patients with relapsing MS.