Prevalence and relevance of Type D personality in fibromyalgia

Objective: Distressed (Type D) personality, combining high negative affectivity and social inhibition, is linked to poor health in various populations. Because patients with fibromyalgia experience high negative affect and show signs of social inhibition, this study aimed to examine the prevalence of Type D's components and their associations with health in an additive (worse health with both components present) or synergistic way (components amplifying each other's effects).

Method: Type D personality and physical and mental health were assessed online by 558 patients with self-reported fibromyalgia (94% women, age 47 ± 11 (21-77)years) by the Type D Scale-14 and RAND-36 Health Status Inventory.

Results: Using the standard cutscores, Type D personality was present in 56.5% of patients. Negative affectivity alone and combined with social inhibition was associated with worse mental and, more limited, physical health, but no interactive (synergistic) associations were found.

Conclusions: Type D personality in fibromyalgia exceeds prevalence estimates in general, cardiovascular and chronic pain populations. Some indication of an additive but not of a synergistic effect was found, particularly for mental health, with clearly the largest associations for negative affectivity. The high prevalence of Type D's components may have specific treatment implications.