Temporal associations between use of psychoactive substances and somatic symptoms in the daily lives of people with fibromyalgia.

Objective: Consumption of psychoactive substances-alcohol, nicotine, caffeine, opioids, and cannabis-is common among people with fibromyalgia. Associations between the use of substances and somatic symptoms could reflect efforts to cope with symptoms, aggravation or alleviation of symptoms after the use of substances, or a combination of these. To date, no study has provided insight into temporal associations between the consumption of psychoactive substances and fluctuations in somatic symptoms. We explored whether changes in ratings of pain and fatigue (mental and physical) predicted the later use of psychoactive substances or vice versa (substance use predicting later change in symptoms).

Design: Micro-longitudinal design.

Setting/subjects: Fifty adults (88% female, 86% White, mean age of 44.9 years) with fibromyalgia.

Methods: Participants completed ecological momentary assessments of substance use, pain intensity, and physical/mental fatigue 5 times per day for 8 days.

Results: Results of multilevel models indicated that momentary increases in fatigue showed a consistent association with greater odds of later use of psychoactive substances, whereas momentary increases in pain were related to lower odds of later cannabis and nicotine use and higher odds of later alcohol use. Only nicotine use predicted later mental fatigue.

Conclusion: Findings highlight the importance of individualized interventions for symptom management or problems related to the use of psychoactive substances. We observed that although somatic symptoms predicted later use of substances, use of substances did not show appreciable effects with regard to alleviating somatic symptoms in people with fibromyalgia.