Health care fragmentation and blood pressure control among adults taking antihypertensive medication

To determine the association of fragmented ambulatory health care with uncontrolled blood pressure (BP) and apparent treatment-resistant hypertension (aTRH) among older adults taking antihypertensive medication, overall and by race and gender.

Cross-sectional study using data from 2868 REasons for Geographic And Racial Differences in Stroke (REGARDS) study participants 66 years and older who completed a study examination in 2013-2016, had Medicare fee-for-service coverage, and were taking antihypertensive medication.

We used logistic regression to analyze the association of fragmented health care with uncontrolled BP and aTRH. Fragmented health care was operationalized as a reversed Bice-Boxerman Index score in the 75th percentile or higher, calculated using the number of ambulatory providers and health care visits in the year preceding the study examination. Uncontrolled BP was defined by systolic BP of at least 140 mm Hg or diastolic BP of at least 90 mm Hg. aTRH was defined by taking 3 or more classes of antihypertensive medication with uncontrolled BP or 4 or more classes with controlled BP.

The overall adjusted odds ratios (95% CIs) for uncontrolled BP, aTRH with controlled BP, and aTRH with uncontrolled BP associated with fragmented health care were 1.10 (0.89-1.37), 1.08 (0.80-1.47), and 1.32 (0.96-1.81), respectively. Fragmented health care was not associated with uncontrolled BP or aTRH among White participants, women, or men. Among Black participants, the odds ratio (95% CI) associated with fragmented health care was 1.21 (0.81-1.82) for uncontrolled BP, 1.22 (0.72-2.07) for aTRH with controlled BP, and 1.82 (1.07-3.11) for aTRH with uncontrolled BP.

Fragmented health care may increase the likelihood of aTRH with uncontrolled BP among older Black adults taking antihypertensive medication.