Beyond pain in fibromyalgia: insights into the symptom of fatigue

Table 1 Correlates of fatigue

Correlate	Design and sample	Direction
Pain	4 cross-sectional [5, 31–33]	Positive
Pain	6 longitudinal (5 months, 30 days, 10 days, 6 days) [21, 22, 28, 29, 34–36]	Positive
Sleep duration	1 longitudinal (30 days) [34]	Negative
Sleep quality	2 longitudinal (6 days, 3 days) [21, 37]	Negative
Sleep disturbance	1 cross-sectional [5]	Positive
Sleep disturbance	1 longitudinal (30 days) [29, 35]	Positive
Anxiety and depression	5 cross-sectional [5, 31, 38–40]	Positive
Anxiety and depression	4 longitudinal (5 months, 30 days, 6 days) [21, 22, 29, 34, 35]	Positive
Tenderness	2 cross-sectional [5, 38]	Positive
Stiffness	1 cross-sectional [33]	Positive
Stiffness	1 longitudinal (10 days) [28]	Positive
Disability	2 cross-sectional [5, 33]	Positive
Cognitive complaints	1 cross-sectional [41]	Positive
Gastrointestinal distress	1 cross-sectional [5]	Positive
Negative events	1 longitudinal (30 days) [35]	Positive
Positive events	1 longitudinal (30 days) [35]	Negative same day, positive following day
Positive affect	1 cross-sectional [42]	Negative
Positive affect	1 longitudinal (30 days) [29]	Negative
Negative affect	1 longitudinal (30 days) [29]	Positive
Internal locus of control	1 cross-sectional [43]	Negative
External locus of control	1 cross-sectional [43]	Negative
Emotional distress	1 longitudinal (30 days) [36]	Positive
Fibromyalgia severity	2 cross-sectional [5, 44]	Positive

ISSN: 1478-6362