BackgroundThe growing frail, older population is increasing pressure on hospital services. This is directing the attention of clinical commissioning groups towards more comprehensive approaches to managing frailty in the primary healthcare environment.AimTo review the literature on whether assessment of frailty in primary health care leads to a reduction in unplanned secondary care use.Design & settingA rapid review involving a systematic search of Medline and Medline In-Process.MethodRelevant data were extracted following the iterative screening of titles, abstracts, and full texts to identify studies in the primary or community healthcare setting which assessed the effect of frailty on unplanned secondary care use between January 2005–June 2016.ResultsThe review included 11 primary studies: nine observational studies; one randomised controlled trial (RCT); and one non-randomised controlled trial (nRCT). Eight out of nine observational studies reported a positive association between frailty and secondary care utilisation. The RCT and nRCT reported conflicting findings.ConclusionOlder people identified as frail in a primary healthcare setting were more likely to be admitted to hospital. Based on the limited and equivocal trial evidence, it is not possible to draw firm conclusions regarding appropriate tools for the identification and management of frail older people at risk of hospital admission.