Aim: To explore preferences and barriers towards the design of a loneliness reduction intervention in patients treated for coronary heart disease who experience loneliness.

Design: A qualitative study using patient involvement methodology.

Methods: Seventeen patients participated in either focus groups or individual interview sessions. The interview guide was based on patient involvement methodology. Interviews were analysed using deductive content analysis.

Results: Four overall findings emerged as follows: (a) An intervention involving a social network member must comply with patients perceived social norms; (b) An intervention involving a peer provides benefits from reciprocity and shared experiences, but also requires surplus mental energy; (c) The history of an existing relationship can act as both provider and barrier for confidentiality and (d) Start-up, timeframe and structure of the intervention should be individually tailored to the patient's preferences.

Findings illuminated preferences and barriers towards the design of a loneliness reduction intervention in patients with coronary heart disease.