Health insurance status and hypertension monitoring and control in the United States.

BACKGROUND: In this study, we examined whether insurance status (private, Medicare, Medicaid, no insurance) was associated with the odds of blood pressure (BP) monitoring and control.
METHODS: We used data from the National Health and Nutrition Examination Surveys (NHANES) conducted in 1999 through 2002, defining hypertension as either self-report of elevated BP or an elevated BP value on examination. We conducted multivariate analyses adjusting for age, income, race/ethnicity, body mass index, and medical comorbidities.
RESULTS: Among all hypertensive participants, only 58% of the uninsured had a BP check within 6 months, compared to 82% of the privately insured. Overall, uninsured individuals (adjusted odds ratio 0.63, 95% CI 0.44-0.92) were at lower odds of adequate BP control than the privately insured. Among treated participants, the uninsured were at lower odds of adequate control (adjusted OR 0.42, 95% CI 0.23-0.73) than the privately insured. Among participants who self-reported hypertension but were not taking antihypertensive medications, the odds of elevated BP did not differ by insurance status. No differences in BP control were observed for participants with Medicare or Medicaid compared to those with private insurance, in any comparisons.
CONCLUSIONS: Lack of insurance is associated with lower rates of BP control among treated hypertensives, whereas the odds of elevated BP are similar among untreated hypertensives with different insurance status. Variation in BP control between the uninsured and privately insured with hypertension is likely related to differences in appropriate treatment intensification or adherence, rather than differences in rates of treatment initiation.