Background: Depression is common in people with long term conditions (LTCs) and is associated with worse medical outcomes. Understanding the mechanisms underpinning this relationship could help predict who is at increased risk of adverse medical outcomes, and lead to the development of novel interventions. Perseverative negative cognitive processes, such as worry and rumination, involve repetitive and frequent thoughts about oneself and one's concerns. These processes have been associated with negative affect, and also adverse medical outcomes. The results of prospective studies, which would allow causal inferences to be drawn, are more equivocal however. Furthermore, the majority of studies have been conducted in physically healthy individuals, and we do not know to what extent these findings will generalise to people with LTCs.
Methods/design: Electronic databases will be searched using a search strategy including controlled vocabulary and text words related to perseverative negative cognitive processes (such as worry and rumination) and negative affect (including depression and anxiety). Records will be hand-searched for terms related to LTCs. Citation and bibliography searching will be conducted, and authors of included studies will be contacted to identify unpublished studies. Studies will be included if they contain a standardised measure of the prospective association between perseverative negative cognitive processes and negative affect, or vice versa, in people with LTCs. Narrative and meta-analytic methods will be used to synthesize the data collected.
Discussion: This review will identify and synthesise studies of the prospective association between perseverative negative cognitive processes and negative affect among people with LTCs. The findings will help to identify whether worry and rumination could cause depression and anxiety in people with LTCs, and might indicate whether perseverative negative cognitive processes are appropriate targets for treatment.