Cluster-randomized controlled trial for the early promotion of clinic visits for untreated hypertension

Despite clear evidence of the benefits of lowering blood pressure among patients with hypertension, the treatment rate remains <40% worldwide. In the present trial, we aimed to investigate the effects of the early promotion of clinic visits among patients with untreated hypertension detected during annual health checkups. This was a worksite-based, parallel group, cluster-randomized trial with blinded outcome assessment. Employees of 152 Japanese supermarket stores found to have untreated hypertension (blood pressure levels ≥ 160/100 mmHg) during health checkups were assigned to an early promotion group (encouraged to visit a clinic in face-to-face interviews and provided with a referral letter to a physician as well as a leaflet) or a control group (received usual care), according to random assignment. The primary outcome was the completion of a clinic visit within 6 months. Odds ratios with 95% confidence intervals for the early promotion group versus the control group were estimated using multilevel logistic regression with random effects of clusters. A total of 273 participants (mean age 50.3 years, 55% women) from 107 stores were assigned to the early promotion group (138 from 55 stores) or control group (135 from 52 stores). During the 6-month follow-up, 47 (34.1%) participants in the early promotion group visited a clinic, as did 26 (19.3%) in the control group (odds ratio 2.33, 95% confidence interval 1.12-4.84, P = 0.024). Early promotion using a referral letter during health checkups significantly increased the number of clinic visits within 6 months completed by participants with untreated hypertension (UMIN000025411).