Continuity of care in primary care and association with survival in older people: a 17-year prospective cohort study.

Background: Although continuity of care is a widely accepted core principle of primary care, the evidence about its benefits is still weak.
Aim: To investigate whether continuity of care in general practice is associated with better survival in older people.
Design and Setting: Data were derived from the Longitudinal Aging Study Amsterdam, an ongoing cohort study in older people in the Netherlands. The study sample consisted of 1712 older adults aged ≥60 years, with 3-year follow-up cycles up to 17 years (1992-2009), and mortality follow-up until 2013.
Method: Continuity of care was defined as the duration of the ongoing therapeutic relationship between patient and GP. The Herfindahl-Hirschman Index was used to calculate the continuity of care (COC). A COC index value of 1 represented maximum continuity. COC index values <1 were divided into tertiles, with a fourth category for participants with maximum COC. Cox regression analysis was used to investigate the association between COC and survival time.
Results: Seven hundred and forty-two participants (43.3%) reported a maximum COC. Among the 759 participants surviving 17 years, 251 (33.1%) still had the same GP. The lowest COC category (index >0-0.500) showed significantly greater mortality than those in the maximum COC category (hazard ratio (HR) = 1.20, 95% CI = 1.01 to 1.42). There were no confounders that affected this HR.
Conclusion: This study demonstrates that low continuity of care in general practice is associated with a higher risk of mortality, strengthening the case for encouragement of continuity of care.
(© British Journal of General Practice 2016.)