Abstract 5861: Determinants of Poor Blood Pressure Control in Hypertensive Patients With Diabetes: A Stitch Substudy
Purpose: Despite improvements in BP control generally, control rates for patients with hypertension (HTN) and diabetes (DM) are less than half of those without DM. Whether this reflects the lower BP targets for those with DM (130/80 mmHg), resistance to aggressive therapy/use of diuretics by health care professionals and/or a greater prevalence of refractory HTN in patients with DM is unclear. Therefore we conducted a post hoc exploratory analysis to assess BP control in patients with HTN and DM who participated in the STITCH study, a cluster randomized controlled trial in southwestern Ontario.
Methods: Data were collected in 45 general practices, which enrolled hypertensive patients demonstrating uncontrolled BP at trial entry. Pretest and posttest BP measurements were taken approximately 6 months apart. Antihypertensive medication changes throughout this follow-up period were documented. Of the 2104 hypertensive patients that were analyzed in the STITCH study, 320 had a diagnosis of DM.
Results: Patients with DM were significantly less likely to reach target than those without DM (26% vs. 64%, p< 0.001). Notably, the mean BP reduction over the 6 month follow-up was comparable between DM (ΔSBP: 18.7±18.2 mmHg, ΔDBP: 8.2±11.9 mmHg) and non-DM patients (ΔSPB: 19.9±18.0 mmHg, ΔDBP: 9.2±10.5 mmHg) as was the proportion of patients reaching a common target of 140/90 mmHg (DM: 60.6%; Non-DM: 63.6%, p=0.319). However, despite not achieving any greater BP reduction, DM patients received more intensive BP therapy, measured as standard daily doses (SDD) (mean SDD: DM: 2.35, 95% CI: 2.17 to 2.54; non-DM: 1.65, 95% CI: 1.59 to 1.71; p<.001). Further, DM patients received MORE INTENSIVE diuretic therapy (mean SDD of diuretic: DM: 0.87, 95% CI: 0.78 to 0.97; non-DM: 0.74, 95% CI: 0.71 to 0.78; p=0.01).
Conclusions: In a community setting, patients with HTN and DM are less likely to reach target BP despite receiving more intensive antihypertensive drug therapy. They are also more likely to be treated with higher doses of diuretics. Thus, in hypertensive patients with DM, failure to reach treatment targets appears to reflect both the lower targets and greater resistance to antihypertensive therapy and is not due to less aggressive therapy and/or under-treatment with diuretics.