Impact of Monthly Headache Days on Migraine-Related Quality of Life: Results From the CaMEO Study
Richard B. Lipton1, Patricia Pozo-Rosich2,3, Serena L. Orr4,5, Michael L. Reed6, Kristina M. Fanning6, Brett Dabruzzo7, Dawn C. Buse1
1Albert Einstein College of Medicine, 2Headache Unit, Neurology Department, Vall d’Hebron University Hospital, 3Headache Research Group, VHIR, Universitat Autonoma of Barcelona, 4Alberta Children’s Hospital, University of Calgary, 5Cumming School of Medicine, University of Calgary, 6Vedanta Research, 7AbbVie
Objective:
To characterize the direct impact of monthly headache days (MHDs) on quality of life in people with migraine and the potential mediating effects of anxiety, depression, and allodynia.
Background:

Higher MHD frequency has been associated with greater disability and lower health-related quality of life in people with migraine.

Design/Methods:
CaMEO was a longitudinal web-based study that identified US individuals who met International Classification of Headache Disorders-3 criteria for migraine based on a validated questionnaire. Linear regression models were performed to characterize the impact of MHDs on Migraine-Specific Quality of Life Questionnaire v2.1 (MSQ) subdomain scores at baseline. The indirect effects of anxiety (Generalized Anxiety Disorder-7 [GAD-7]), depression (Patient Health Questionnaire-9 [PHQ-9]), and allodynia (Allodynia Symptom Checklist-12 [ASC-12]) were assessed in mediation models. 
Results:

A total of 12,810 respondents were included in this analysis. Monthly headache day frequencies of 0-3, 4-7, 8-14, and ≥15 MHDs were reported by 57.9%, 21.2%, 11.4%, and 9.5% of respondents, respectively. Linear regression (adjusted for age, gender, income, and obesity) showed a significant negative relationship (P<0.001) between MHDs and MSQ-Role Function-Restrictive ([RFR] adjusted R2=0.305), Role Function-Preventive ([RFP] adjusted R2=0.240), and Emotional Function ([EF], adjusted R2=0.324) subdomain scores, where greater MHD frequencies were associated with lower MSQ scores. These results showed that 30.5% of the variance in MSQ-RFR scores, 24.0% of the variance in MSQ-RFP scores, and 32.4% in MSQ-EF scores can be predicted by MHDs. Mediation models found that the indirect impact of anxiety, depression, and allodynia accounted for 6.0%, 16.9%, and 10.5% of MHDs impact on MSQ-RFR scores; 2.3%, 24.3% and 16.1% of MSQ-RFP scores; and 5.6%, 15.2%, and 9.6% of MSQ-EF scores.

Conclusions:
MHD category has a substantial direct negative effect on all MSQ subdomain scores. Indirect effects of MHDs on MSQ domains were greatest for depression, followed by allodynia, and then anxiety for all subdomains.