Association Between a Temporary Reduction in Access to Health Care and Long-term Changes in Hypertension Control Among Veterans After a Natural Disaster

Abstract

Importance: Temporary disruptions in health care access are common, but their associations with chronic disease control remain unknown.

Objective: To evaluate whether long-term changes in chronic disease control were associated with a temporary 6-month decrease in access to health care services.

Design, setting, and participants: This cohort study examined the long-term changes in chronic disease control associated with the 6-month closure of the Manhattan facility of the Veterans Affairs (VA) New York Harbor Healthcare System after superstorm Sandy, which caused a significant disruption in health care access for veterans in the region. Electronic health records from the VA Healthcare System between October 29, 2010, and October 29, 2014, were used to identify a total of 81 544 veterans who were and were not exposed to the 6-month closure of the VA Manhattan Medical Center after superstorm Sandy. Of those, 19 207 veterans were included in the exposed cohort and 62 337 were included in the nonexposed control cohort, which included veterans who were equally exposed to the storm but who retained regular access to health care from 3 VA medical centers (Brooklyn and the Bronx in New York and New Haven in Connecticut) during and after the storm. A difference-in-differences analysis was used to assess within-patient changes in chronic disease control over time between a cohort that was exposed to decreased health care access compared with a similar cohort that was not exposed to decreased access. All analyses adjusted for individual demographic and socioeconomic characteristics, between-zip code differences, and common time trends. Data analyses were conducted between February 1, 2016, and September 30, 2019.

Exposure: The 6-month closure of the VA Manhattan Medical Center after superstorm Sandy on October 29, 2012.

Main outcomes and measures: The outcomes measured were uncontrolled blood pressure (defined as mean blood pressure per patient per quarter >140/90 mm Hg), uncontrolled diabetes (defined as mean hemoglobin A1c per patient per quarter >8%), uncontrolled cholesterol (defined as mean low density lipoprotein per patient per quarter >140 mg/dL), and patient weight.

Results: Among the 81 544 veterans included in the study, the mean (SD) age was 62.1 (17.6) years, and 93.6% were men, 62.7% were white, and 31.8% were black. At the 3-month midpoint of the 6-month facility closure of the VA Manhattan Medical Center, an absolute decrease of 24.8% (95% CI, -26.5% to -23.0%; P < .001) was observed in the percentage of veterans who had any VA primary care visit per quarter compared with a baseline of 47.8% before the closure (relative decrease, 51.9%; 95% CI, -55.4% to -48.1%; P < .001). One year after the facility reopened, no differential change was observed in the percentage of patients with a primary care visit between the exposed vs nonexposed cohorts (absolute decrease, -0.1%; 95% CI, -1.5% to 1.4%; P = .94); however, patients in the exposed cohort were 25.9% more likely to have uncontrolled blood pressure than patients in the nonexposed cohort (unadjusted increase, 5.5% in the exposed cohort vs 1.3% in the nonexposed cohort; adjusted absolute increase, 5.0%; 95% CI, 3.5%-6.0%; P < .001). Two years after superstorm Sandy, patients in the exposed cohort were 10.9% more likely to experience uncontrolled blood pressure than those in the nonexposed cohort (unadjusted increase, 5.2% in the exposed cohort vs 3.5% in the nonexposed cohort; adjusted absolute increase, 2.1%; 95% CI, 0.5%-3.6%; P < .001). Compared with the nonexposed cohort, the exposed cohort also experienced a decrease in filled medication prescriptions per patient per quarter of 6.9% during the facility closure (absolute decrease, -0.7 prescriptions filled per patient per quarter; 95% CI, -0.9 to -0.5; P < .001) and of 2.2% a year after the facility reopened (absolute decrease, -0.2 prescriptions filled per patient per quarter; 95% CI, -0.4 to -0.1; P = .04). No differential changes were observed in uncontrolled diabetes, uncontrolled cholesterol, or patient weight.

Conclusions and relevance: In this study, a temporary period of decreased access to health care services was associated with increased rates of uncontrolled hypertension, but not with increased rates of uncontrolled diabetes or hyperlipidemia, more than 1 year after the Manhattan VA facility reopened. Temporary gaps in access to health care may be associated with long-term increases in uncontrolled blood pressure among patients with hypertension.

Figure 1.. Unadjusted Rates of Primary Care Visits and Uncontrolled Blood Pressure Among Exposed vs Nonexposed Cohorts

The exposed cohort comprised veterans who used the Manhattan Veterans Affairs (VA) Medical Center as their usual place of care before superstorm Sandy and who experienced decreased access to health care services during the facility's closure. The nonexposed control cohort comprised veterans who were assigned to the VA Bronx, Brooklyn, or West Haven medical centers and who did not experience decreased health care access after superstorm Sandy. PC indicates primary care.

Figure 2.. Differential Changes in Quarterly Rates of Uncontrolled Blood Pressure Among Exposed vs Nonexposed Cohorts by Subgroup With and Without a Hypertension Diagnosis Before Superstorm Sandy

A, Patients without hypertension diagnosis before storm. B, Patients with hypertension diagnosis before storm. Points indicate the estimated average differential change between the exposed vs nonexposed groups in the percentage of patients with uncontrolled blood pressure in each quarter year since the storm, using a difference-in-differences regression analysis that adjusted for individual fixed effects, between–zip code differences, and common time trends. Vertical lines indicate the 95% CIs. The shaded area indicates the 6-month facility closure.