Stress and sleep duration predict headache severity in chronic headache sufferers

Abstract

The objective of this study was to evaluate the time-series relationships between stress, sleep duration, and headache pain among patients with chronic headaches. Sleep and stress have long been recognized as potential triggers of episodic headache (<15 headache days/month), though prospective evidence is inconsistent and absent in patients diagnosed with chronic headaches (≥15 days/month). We reanalyzed data from a 28-day observational study of chronic migraine (n=33) and chronic tension-type headache (n=22) sufferers. Patients completed the Daily Stress Inventory and recorded headache and sleep variables using a daily sleep/headache diary. Stress ratings, duration of previous nights' sleep, and headache severity were modeled using a series of linear mixed models with random effects to account for individual differences in observed associations. Models were displayed using contour plots. Two consecutive days of either high stress or low sleep were strongly predictive of headache, whereas 2 days of low stress or adequate sleep were protective. When patterns of stress or sleep were divergent across days, headache risk was increased only when the earlier day was characterized by high stress or poor sleep. As predicted, headache activity in the combined model was highest when high stress and low sleep occurred concurrently during the prior 2 days, denoting an additive effect. Future research is needed to expand on current findings among chronic headache patients and to develop individualized models that account for multiple simultaneous influences of headache trigger factors.

Figure 1

Cross-correlation between stress (AIR) and headache SUM (top panel), sleep quantity and headache SUM (middle panel) and stress (AIR) and sleep quantity (lower panel). For each plot, individual tick marks represent a single subject with the y-axis displaying the Pearson correlation as a function of time lag in days. The bar plot reflects the average of individual associations.

Figure 2

A contour plot depicting the smoothed headache SUM using color as a function of today's stress (x-axis) and yesterday's stress (y-axis). The top panel displays the smoothed observed data, and the bottom panel displays the smoothed stress model predictions. The similarity between plots reflects a good fit of the model to the data.

Figure 3

A contour plot depicting the smoothed headache SUM using color as a function of last night's sleep (x-axis) and the previous night's sleep (y-axis). The top panel displays the smoothed observed data, and the bottom panel displays the smoothed sleep model predictions. The similarity between plots reflects a good fit of the model to the data.

Figure 4

A contour plot depicting the smoothed headache SUM using color as a function of stress risk (x-axis) and sleep risk (y-axis). The combination of stress and sleep risks additively combine to predict increased headache activity.