Limited Efficacy of Caffeine and Recovery Costs During and Following 5 Days of Chronic Sleep Restriction

Abstract

Caffeine appears to have limited efficacy for maintaining alertness and wakefulness across 5 days of sleep restriction. Perhaps more importantly, there may be recovery costs associated with caffeine use following conditions of prolonged sleep loss.

Caffeine dosing strategies to optimize alertness during sleep loss

“…Figure shows the experimental mean RT data (orange dots with standard error bars) for each study (Doty et al., ; Kamimori et al., ; Mclellan et al., , ), as well as the UMP‐predicted mean RT profiles for the original studies (dashed orange lines) and the optimal dosing strategies (blue lines) that attempted to enhance neurobehavioural performance, using the same total amount of caffeine as in the original studies (Figure , red arrows). Overall, the UMP satisfactorily predicted the mean RT for the original studies (i.e.…”

“…In contrast, the optimal strategy prescribed more caffeine on later days (with the exception of the last day), owing to increasing sleep pressure, and allocated caffeine at the end of each of the first 4 days of CSR (Figure , blue arrows). Moreover, the optimal strategy did not prescribe caffeine early on the first day of CSR because performance impairment was mitigated by sleep banking (subjects spent 10 hr in bed on five previous nights) (Doty et al., ).…”

“…Here, we revisited these studies to demonstrate the benefit of the proposed algorithm. The studies investigated the effect of caffeine on group‐average performance during chronic sleep restriction (CSR; Study 1 [Doty et al., ; ]), total sleep deprivation (TSD; Study 4 [Mclellan et al., ; ]) or a combination of both (Studies 2 and 3 [Kamimori et al., ; Mclellan et al., ; ]). For additional details on these studies, we refer the reader to Ramakrishnan et al.…”

“…Sleep loss, which is a common stressor for both civilians and military personnel, can severely impair cognitive and physical performance, and thereby diminish productivity and compromise safety. Several studies have demonstrated that, when safely used, caffeine can help to sustain cognitive performance during prolonged periods of restricted sleep (Doty et al., ; Kamimori et al., ; Killgore et al., ; Mclellan, Bell, & Kamimori, ; Mclellan et al., ; Wesensten, Killgore, & Balkin, ). However, these investigations offer caffeine countermeasure guidance that is study‐specific, and which cannot be readily adaptable to any arbitrary sleep‐loss condition.…”

A study of skin characteristics with long‐term sleep restriction in Korean women in their 40s

“…Most sleep‐related studies have identified changes through short‐term sleep deprivation. Studies involving long‐term sleep deprivation (>3 days) have investigated the effect of caffeine on sleep . There are also studies that show that sleep quality is associated with obesity (body mass index, waist circumference, and fat percentage) .…”