Disability Status and Secondary Prevention Among Survivors of Stroke: A Cross‐Sectional Analysis of the 2011 to 2018 National Health and Nutrition Examination Survey

Abstract

Background

Among survivors of stroke, adherence to secondary prevention care is associated with decreased risk of recurrent stroke. However, not all survivors of stroke use secondary stroke prevention treatment. We examined the association between the disability status of survivors of stroke and their treatment and control of diabetes, hyperlipidemia, and hypertension.

Methods and Results

In a cross‐sectional analysis of the 2011 to 2018 National Health and Nutrition Examination Survey, we compared diabetes, hyperlipidemia, and hypertension treatment and control rates among self‐reported survivors of stroke age ≥20 years with and without disability. Disability was defined as self‐reporting any of 5 physical or 4 functional domains assessed using a structured questionnaire. Logistic regression models adjusted for age, sex, race and ethnicity, and history of medical conditions were used to estimate associations between disability status and risk factor treatment and control. The mean age of survivors of stroke was 65.1 years, and 55.5% were female; 76% (95% CI, 72.7%–79.3%) self‐reported at least 1 disability. Age‐standardized treatment rates for diabetes, hyperlipidemia, and hypertension were 33.1% (95% CI, 26.9%–39.2%), 67.5% (95% CI, 62.6%–72.3%), and 78.4% (95% CI, 74.6%–82.2%), respectively. Age‐standardized control rates for diabetes, hyperlipidemia, and hypertension were 86.8% (95% CI, 83.8%–89.8%), 20.5% (95% CI, 15.0%–25.9%), and 47.1% (95% CI, 42.6%–51.7%), respectively. In adjusted models, those with and without disabilities had similar odds of risk factor treatment and control.

Conclusions

In the United States, three‐quarters of survivors of stroke self‐reported a disability, and these patients had similar odds of diabetes, hyperlipidemia, and hypertension treatment and control compared with those without disability.

Nonstandard Abbreviations and Acronyms

NHANES

National Health and Nutrition Examination Survey

Clinical Perspective.

What Is New?

• Among US survivors of stroke, three‐quarters reported a disability.

• However, their treatment and control rates for diabetes, hyperlipidemia, and hypertension were similar to those without disabilities.

What Are the Clinical Implications?

• Efforts to improve treatment and control of vascular risk factors should target the broader population of survivors of stroke.

Among survivors of stroke, adherence to secondary prevention care is associated with decreased risk of recurrent stroke. ¹ Survivors of stroke with disabilities are particularly vulnerable to recurrent stroke and death. ² However, prior studies report conflicting findings as to whether stroke sequelae severity is associated with use or receipt of recommended secondary prevention care. ³ , ⁴ , ⁵ , ⁶ , ⁷ , ⁸ , ⁹ Some studies report that patients with more severe stroke sequelae or disability were less likely to use or receive risk factor treatment or had lower control, ³ , ⁴ , ⁵ , ⁶ , ⁷ whereas others report no significant associations. ⁸ , ⁹ , ¹⁰

We used the 2011 to 2018 National Health and Nutrition Examination Survey (NHANES) to identify a cohort of US patients who had survived a previous stroke. NHANES provides information characterizing disability status and patterns of secondary prevention care. We hypothesize that survivors of stroke with and without disabilities will differ in the rates at which diabetes, hyperlipidemia, and hypertension are treated and controlled. Our objective was to examine among survivors of stroke the association between disability status and vascular risk factor treatment and control.

Methods

All data are publicly available at the NHANES website and can be accessed at https://wwwn.cdc.gov/Nchs/Nhanes/Search/.

Patient Consent

NHANES was approved by the National Center for Health Statistics Ethics Review Board, and written informed consent was obtained from all participants or legally authorized representatives. ¹¹

Study Population

NHANES is a deidentified and publicly available data set collected every 2 years by the Centers for Disease Control and Prevention. ¹² Participants are selected through a stratified, multistage, probability‐sampling design. NHANES is designed to be representative of the civilian, noninstitutionalized population of the United States (50 states and District of Columbia). It contains demographics, self‐reported health information, physical exam, and blood samples. Data were merged across the 4 NHANES survey cycles (2011–2012, 2013–2014, 2015–2016, 2017–2018) that contained the Physical Functioning Questionnaire. New sample weights were created to merge across cycles, in accordance with NHANES analytic guidelines. The study population was all participants ≥20 years of age from 2011 to 2018 who replied yes to the question, “Has a doctor or other health professional ever told you that you had a stroke?”

Disability Definitions

Among participants who self‐reported a history of stroke, disability domains were defined according to previous research methods (Data S1). ¹³ The NHANES Physical Functioning Questionnaire asks participants about their degree of difficulty in 5 physical disability domains and the presence or absence of limitations in 4 functional disability domains.

The physical domain includes (1) activities of daily living (ADLs), (2) instrumental ADLs, (3) leisure and social activities, (4) lower extremity mobility, and (5) general physical activities (Data S1). ¹³ Responses included no difficulty, some difficulty, much difficulty, unable to do, and do not do this activity. We categorized each physical disability's severity using cutoffs consistent with prior reports; ¹⁴ , ¹⁵ severe disability was defined as unable to do an activity; moderate disability was defined as much difficulty in an activity without being unable to do any activity; no disability was defined as some or no difficulty doing all activities in the domain. The functional domain includes limitations in (1) ability to work, (2) amount or type of work, (3) walking without using any special equipment, and (4) memory and confusion.

Specific physical disabilities’ severity was categorized as none, moderate, or severe. A participant was defined as having a specific functional disability if they replied yes to a functional limitation question (Data S1). ¹³ Participants were categorized as having any physical disability if they had 1 or more moderate or severe physical disabilities, having any functional disability if they had 1 or more functional limitations, and having any disability if they had any physical or functional disability.

Demographics, Socioeconomic Status, and Medical History

NHANES includes information on participants' self‐reported demographics (age, sex, race and ethnicity, education, and family income to poverty ratio) and medical conditions (history of arthritis, cancer, cardiovascular disease [angina, congestive heart failure, coronary artery disease, or myocardial infarction], and kidney disease). Race and ethnicity were self‐reported by NHANES participants based on fixed‐category questions and recoded by the Centers for Disease Control and Prevention into 6 groups: Mexican American, Non‐Hispanic Asian, Non‐Hispanic Black, Non‐Hispanic White, Other Hispanic, and Other Race–Including Multiracial. ¹⁶ Other Hispanic included participants who self‐identified as Hispanic but not Mexican American. ¹⁶ Other Race included participants who identified as American Indian or Alaska Native, multiracial, or Native Hawaiian or Pacific Islander. ¹⁶ , ¹⁷

Stroke Risk Factors

The 3 risk factors of interest were diabetes, hyperlipidemia, and hypertension (Data S1). A participant was defined as having diabetes if they had any of the following: self‐reported history of diabetes, self‐reported use of insulin or oral hypoglycemic agents, or laboratory measurement of hemoglobin A1c ≥6.5%. Hyperlipidemia was defined as self‐reported history of high cholesterol, self‐reported ever being told to use cholesterol medication, self‐reported current use of cholesterol medication, or laboratory measurement of low‐density lipoprotein cholesterol >100 mg/dL. Laboratory quality control and quality assurance protocol are described in NHANES Laboratory Protocol. ¹⁸ Hypertension was defined as self‐reported history of hypertension, self‐reported ever being told to use antihypertensive medications, self‐reported current use of antihypertensive medications, or physical exam measurement of blood pressure≥130/80 mm Hg. In sensitivity analyses, physical exam measurement of blood pressure≥140/90 mm Hg was used to define hypertension for participants enrolled in the years 2011 to 2016, consistent with the hypertension guideline that was relevant during those years. ¹⁹ Blood pressure was calculated as the mean of 3 seated measurements using an automated machine (OMRON HEM 907 XL). ²⁰ Risk factor prevalence was calculated among participants who had available laboratory data for A1c or low‐density lipoprotein cholesterol levels or physical exam data for blood pressure (Table S1).

Treatment for diabetes, hyperlipidemia, and hypertension was defined as self‐reported current use of insulin or oral hypoglycemic agents or use of any medication to treat cholesterol or hypertension (Data S2). Treatment rates were calculated among participants who had the risk factor of interest and had available data for self‐reported current medication use (Table S1).

Risk factor control was defined as hemoglobin A1c ≤7%, low‐density lipoprotein cholesterol<70 mg/dL, and blood pressure <130/80 mm Hg, respectively, for diabetes, hyperlipidemia, and hypertension, based on the most recent clinical guidelines for secondary prevention of stroke among survivors (Data S2). ²¹ In sensitivity analyses, hypertension control was defined as <140/90 mm Hg for participants enrolled in 2011 to 2016, consistent with the hypertension guideline that was relevant during those years. ¹⁹ Risk factor control rates were calculated among participants who had available laboratory data for A1c or low‐density lipoprotein cholesterol levels or physical exam data for blood pressure (Table S1).

Statistical Analysis

We incorporated the appropriate National Center for Health Statistics–derived survey weights to account for the complex NHANES sampling design and to make the estimates reported here nationally representative of the noninstitutionalized civilian population of adults ≥20 years of age in the United States from 2011 to 2018. Participants with missing stroke history were excluded; among the included participants, no participant was missing disability status (Figure 1). We summarized patients' characteristics using means and SEs for continuous variables and proportions and accompanying 95% CIs for categorical variables. We compared demographics, medical histories, and risk factor prevalence, treatment, and control between survivors of stroke with and without disability.

Figure 1. Participant inclusion/exclusion diagram, NHANES 2011 to 2018*.

*During the 2011 to 2018 NHANES cycles, all participants ≥20 years of age were asked about history of stroke as part of the Medical Conditions Questionnaire. In the analytic population (n=913), no participant was missing any disability status. NHANES indicates National Health and Nutrition Examination Survey.

Risk factor prevalence, treatment, and control rates were age standardized to the 2013 to 2017 US population's age distribution using the 5‐year American Community Survey–Public Use Microdata Sample.

We used design‐based chi‐square tests and t tests when appropriate. SEs were obtained with the Taylor series (linearization) method in accordance with NHANES analytic guidelines. We performed multiple logistic regressions to compute odds ratios (ORs) for the association of any disability with risk factor prevalence, treatment, and control, adjusting for 7 confounders (age, sex, race and ethnicity, and medical conditions [history of arthritis, cancer, cardiovascular disease, and kidney disease]). Reported P values were based on 2‐sided tests. P values of 0.05 were considered statistically significant. RStudio version 2022.07.2 and the survey package version 4.1–1 were used to perform all analyses. ²² Reporting of results followed the National Center for Health Statistics Data Presentation Standards for Proportions. ²³ We used the Strengthening the Reporting of Observational Studies in Epidemiology cohort checklist when writing our report. ²⁴

Results

Across the 4 NHANES survey cycles from 2011 to 2018, data for 39 156 individuals were available and information on stroke history was obtained from participants ≥20 years of age. Of the 22 617 individuals ≥20 years of age, 21 679 self‐reported no history of stroke and 25 were missing self‐reported stroke history, leaving a total of 913 (unweighted proportion 4.0%) individuals ≥20 years of age who self‐reported having had a stroke and were included in the analyses (Figure 1).

The mean age of survivors of stroke was 65.1 years (SE, 0.58), 55.5% (95% CI, 51.2%–59.8%) were female, and 66.4% (95% CI, 61.4%–71.4%) were non‐Hispanic White (Table 1).

Table 1.

Characteristics of US Survivors of Stroke ≥20 Years of Age, Overall and According to Disability Status, NHANES 2011 to 2018

	Proportions (95% CI)			P value
	Overall	Has any disability	No disability
Age, y, mean (SE)	65.1 (0.58)	65.9 (0.6)	62.6 (1.2)	0.02
Female sex, % (95% CI)	55.5% (51.2%–59.8%)	56.9% (52.1%–61.7%)	51.2% (42.2%–60.3%)	0.29
Arthritis, % (95% CI)	55.7% (51.3%–60.2%)	63.1% (57.9%–68.4%)	32.9% (24.3%–41.4%)	P<0.001
Cancer, % (95% CI)	23.4% (19.1%–27.7%)	25.2% (19.8%–30.5%)	18% (10.4%–25.6%)	0.15
Heart disease, % (95% CI)	36.1% (31.6%–40.6%)	40.2% (35.0%–45.4%)	23.4% (14.5%–32.3%)	0.002
Kidney disease, % (95% CI)	11.9% (9.72%–14.2%)	13% (10.5%–15.6%)	8.59% (3.38%–13.8%)	0.15
Education, % (95% CI)				P<0.001
Greater than high school	44.2% (39.5%–49%)	39.1% (34.2%–43.9%)	60.2% (51%–69.3%)
High school or equivalent	31.4% (27.3%–35.5%)	33.5% (28.9%–38.2%)	24.8% (17.1%–32.6%)
Less than high school	24.4% (20.9%–27.9%)	27.4% (23.2%–31.6%)	15% (9.6%–20.4%)
Family income to poverty ratio, % (95% CI)				P<0.001
≤350%	76.1% (71.6%–80.7%)	83.3% (78.6%–88.1%)	53.4% (44.1%–62.8%)
>350%	23.9% (19.3%–28.4%)	16.7% (11.9%–21.4%)	46.6% (37.2%–55.9%)
Race and ethnicity*, % (95% CI)				…
Mexican American	5.0% (3.5%–6.5%)	5.0% (3.2%–6.8%)	5.0% (1.9%–8%)
Non‐Hispanic Asian	2.5% (1.6%–3.4%)	2.6% (1.5%–3.6%)	2.4% (0.9%–3.9%)
Non‐Hispanic Black	15.7% (12.3%–19.1%)	15.3% (11.5%–19%)	16.9% (11.8%–22%)
Non‐Hispanic White	66.4% (61.4%–71.4%)	67.5% (61.8%–73.2%)	63.2% (54.6%–71.9%)
Other Hispanic*	3.8% (2.6%–4.9%)	3.9% (2.7%–5.2%)	…
Other race, including American Indian or Alaska Native, multiracial, or Native Hawaiian or Pacific Islander*	6.6% (3.9%–9.3%)	5.7% (2.7%–8.8%)	…

NHANES indicates National Health and Nutrition Examination Survey.

^*Proportions within the no disability subgroup and P value for t test are suppressed due to effective sample size <30.

After age standardization to the US population, 76.0% of participants (95% CI, 72.7%–79.3%) had at least 1 disability (Figure 2, Table S2), corresponding to ≈5.7 million individuals (SE=279 862) out of 7.5 million survivors of stroke (SE=307 268; Table S2). Among survivors of stroke, the most common disability was being limited in the amount or type of work one can do (66.8% [95% CI, 62.9%–70.8%]), whereas the least common was ADL impairment (14.0% [95% CI, 10.9%–18.0%]; Figure 2, Table S2).

Figure 2. Age‐standardized prevalence of disabilities among US survivors of stroke ≥20 years of age, NHANES 2011 to 2018.

NHANES indicates National Health and Nutrition Examination Survey.

Compared with survivors of stroke without disability, those with any disability were older (65.9 years [SE 0.6] versus 62.6 years [SE 1.2], P=0.02) and more likely to have arthritis (63.1% [95% CI, 57.9%–68.4%] versus 32.9% [95% CI, 24.3%–41.4%], P<0.001), heart disease (40.2% [95% CI, 35.0%–45.4%] versus 23.4% [95% CI, 14.5%–32.3%], P=0.002), lower education levels (less than high school education, 27.4% [95% CI, 23.2%–31.6%] versus 15% [95% CI, 9.6%–20.4%], P<0.001) and lower income (family income to poverty ratio ≤350%, 83.3% [95% CI, 78.6%–88.1%] versus 53.4% [95% CI, 44.1%–62.8%], P<0.001) (Table 1, Table S3).

Prevalence

Compared with survivors of stroke with no disability, those with any disability had higher age‐standardized prevalence of diabetes (40.7% [95% CI, 35.4–45.9] versus 26.8% [95% CI, 19.2–34.4], P=0.01) and hypertension (87.2% [95% CI, 83.7–90.8] versus 78.1% [95% CI, 70.9–85.3], P=0.04) but not hyperlipidemia (87.1% [95% CI, 82.4–91.7] versus 89.6% [95% CI, 82.2–97.1], P=0.52) (Table 2, Table S1). In sensitivity analyses where hypertension diagnosis was defined using a cutoff of 140/90 mm Hg for the years 2011 to 2016 and a cutoff of 130/80 mm Hg for 2017 to 2018, hypertension prevalence was 83.2% (95% CI, 78.9–87.6) versus 68.5% (95% CI, 61.1–75.8) among people with versus without disability, respectively (P=0.002) (Table S4).

Table 2.

Age‐Standardized Prevalence, Treatment, and Control of Vascular Risk Factors, Among US Survivors of Stroke ≥20 Years of Age, Overall and According to Disability Status, NHANES 2011 to 2018

Risk factor status*	Proportions (95% CI)			P value
	Overall	Has any disability	No disability
Diabetes†	37.5% (33.5%–41.4%)	40.7% (35.4%–45.9%)	26.8% (19.2%–34.4%)	0.01
Diabetes treatment‡	33.1% (26.9%–39.2%)	32.6% (26.2%–38.9%)	…	…
Diabetes control†	86.8% (83.8%–89.8%)	86.1% (82.3%–89.9%)	88.9% (82.9%–94.9%)	0.48
Hyperlipidemia§	87.8% (83.4%–92.2%)	87.1% (82.4%–91.7%)	89.6% (82.2%–97.1%)	0.52
Hyperlipidemia treatment||	67.5% (62.6%–72.3%)	66.8% (61.2%–72.3%)	69.7% (59.8%–79.5%)	0.61
Hyperlipidemia control§	20.5% (15.0%–25.9%)	22.5% (15.8%–29.2%)	15.6% (6.14%–25%)	0.25
Hypertension¶	85.1% (82.0%–88.2%)	87.2% (83.7%–90.8%)	78.1% (70.9%–85.3%)	0.04
Hypertension treatment#	78.4% (74.6%–82.2%)	80.3% (76.3%–84.4%)	71.3% (62.9%–79.7%)	0.06
Hypertension control¶	47.1% (42.6%–51.7%)	47.2% (41.6%–52.8%)	46.8% (36.8%–56.8%)	0.94

NHANES indicates National Health and Nutrition Examination Surveys.

^*Age standardized to the 2012 to 2017 American Community Survey‐Public Use Microdata Sample.

^† Among participants with hemoglobin A1c data.

^‡ Among participants with diabetes and treatment data. Proportion within no disability subgroup and P value for t test are suppressed due to effective sample size <30.

^§ Among participants with low‐density lipoprotein data.

^|| Among participants with hyperlipidemia and treatment data.

^¶ Among participants with blood pressure measurement data.

^# Among participants with hypertension and treatment data.

Treatment

Comparing survivors of stroke with any disability versus those with no disabilities, age‐standardized treatment rates did not differ significantly for hyperlipidemia treatment (66.8% [95% CI, 61.2–72.3] versus 69.7% [95% CI, 59.8–79.5], P=0.61) and hypertension treatment (80.3% [95% CI, 76.3–84.4] versus 71.3% [95% CI, 62.9–79.7], P=0.06; Table 2). In sensitivity analyses where hypertension diagnosis was defined using a cutoff of 140/90 mm Hg for the years 2011–2016 and a cutoff of 130/80 mm Hg for 2017–2018, hypertension treatment rates were 84.1% (95% CI, 80.2–87.9) versus 80.8% (95% CI, 73.7–87.9) among people with versus without disability, respectively (P=0.42) (Table S4). Based on analytic guidelines for presenting proportions, ²³ we did not present the diabetes treatment proportion for the subgroup of participants with no disabilities, due to an effective sample size of <30 in this subgroup (Table S1).

In logistic regression analyses adjusted for age, sex, race and ethnicity, and medical history, having any disability was not significantly associated with diabetes treatment (OR, 0.63 [95% CI, 0.29–1.34], P=0.24), hyperlipidemia treatment (OR, 0.80 [95% CI, 0.46–1.41], P=0.45), or hypertension treatment (OR, 1.62 [95% CI, 0.95–2.78, P=0.08] (Table 3). In sensitivity analyses where hypertension diagnosis was defined using a cutoff of 140/90 mm Hg for the years 2011 to 2016 and a cutoff of 130/80 mm Hg for 2017 to 2018, having any disability was not significantly associated with hypertension treatment (OR, 1.26 [95% CI, 0.77–2.08], P=0.36) (Table S5).

Table 3.

Disability Status Associated^* With Vascular Risk Factor Treatment and Control, Among US Stroke Survivors ≥20 Years of Age, NHANES 2011 to 2018

Outcome variable	Independent variable	OR (95% CI)	P value
Diabetes treatment†	Has any disability (Ref: None)	0.63 (0.29–1.34)	0.24
Diabetes control‡	Has any disability (Ref: None)	0.74 (0.35–1.56)	0.43
Hyperlipidemia treatment§	Has any disability (Ref: None)	0.80 (0.46–1.41)	0.45
Hyperlipidemia control||	Has any disability (Ref: None)	1.13 (0.43–2.96)	0.80
Hypertension treatment#	Has any disability (Ref: None)	1.62 (0.95–2.78)	0.08
Hypertension control¶	Has any disability (Ref: None)	1.14 (0.67–1.94)	0.63

NHANES indicates National Health and Nutrition Examination Survey; and OR, odds ratio.

^*Multiple logistic regression adjusted for age, sex, race and ethnicity, and medical conditions (history of arthritis, cancer, cardiovascular disease [angina, congestive heart failure, coronary artery disease, or myocardial infarction], and kidney disease).

^† Among participants with diabetes and treatment data.

^‡ Among participants with hemoglobin A1c data.

^§ Among participants with hyperlipidemia and treatment data.

^|| Among participants with low‐density lipoprotein data.

^¶ Among participants with blood pressure measurement data.

^# Among participants with hypertension and treatment data.

Control

Among survivors of stroke with and without disabilities, age‐standardized rates did not differ significantly for diabetes control (86.1% [95% CI, 82.3–89.9] versus 88.9% [95% CI, 82.9–94.9], P=0.48), hyperlipidemia control (22.5% [95% CI, 15.8–29.2] versus 15.6% [95% CI, 6.14–25.0], P=0.25), and hypertension control (47.2% [95% CI, 41.6–52.8] versus 46.8% [95% CI, 36.8–56.8], P=0.94; Table 2). In sensitivity analyses where hypertension diagnosis was defined using a cutoff of 140/90 mm Hg for the years 2011 to 2016 and a cutoff of 130/80 mm Hg for 2017 to 2018, hypertension control was 65.9% (95% CI, 61.0–70.9) versus 69.8% (95% CI, 60.7–78.9) among people with versus without disability, respectively (P=0.46) (Table S4).

In logistic regression analyses adjusting for age, sex, race and ethnicity, and medical history, having any disability was not significantly associated with diabetes control (OR, 0.74 [95% CI, 0.35–1.56], P=0.43), hyperlipidemia control (OR, 1.13 [95% CI, 0.43–2.96], P=0.80), and hypertension control (OR, 1.14 [95% CI, 0.67–1.94], P=0.63) (Table 3). In sensitivity analyses where hypertension diagnosis was defined using a cutoff of 140/90 mm Hg for the years 2011 to 2016 and a cutoff of 130/80 mm Hg for 2017 to 2018, having any disability was not significantly associated with hypertension control (OR, 0.90 [95% CI, 0.54–1.50], P=0.69) (Table S5).

Discussion

This cross‐sectional study provides nationally representative estimates of risk factor prevalence, treatment and control among community‐dwelling survivors of stroke, stratified by disability status. Approximately 5.7 million survivors of stroke had at least 1 disability, corresponding to three‐quarters of US noninstitutionalized, civilian individuals ≥20 years of age who have a history of stroke. Among survivors of stroke, having any disability was not significantly associated with odds of diabetes, hyperlipidemia, or hypertension treatment or control, consistent with findings from prior studies. ⁸ , ¹⁰ However, rates of certain risk factor treatment and control were suboptimal, with only a third of survivors of stroke receiving diabetes treatment when indicated and fewer than half of those with hyperlipidemia and hypertension achieving successful control. These findings suggest stroke secondary prevention needs to be improved in the United States, regardless of patient disability status. Stroke secondary prevention care may benefit from multidisciplinary or organizational interventions in the health care system, ²⁵ rather than educational or behavioral interventions at the individual level.

To the best of our knowledge, this study provides the most recent nationally representative estimate of the disability status of community‐dwelling survivors of stroke in the United States. Among survivors of stroke in the United States sampled in the 1990s, 40.8% had partial or complete dependence in ADLs, ²⁶ higher than the 14% rate found in our study. This difference may be due to the prior study's inclusion of only survivors of stroke aged ≥65 years whereas we include survivors of stroke aged ≥20 years. Among survivors of stroke in the original Framingham cohort recruited from 1948 to 1950, 26% were dependent in ADLs at 6 months post stroke. ²⁷ The lower rate of ADL impairments we observed is consistent with the decreased disability prevalence in the community‐dwelling population during recent decades. ²⁸ Other explanations for differences between these studies and our findings include differences in participants' age, different instruments for measuring disability (eg, self‐report versus clinician judgment), ²⁹ and improvements over time in acute stroke treatment and secondary prevention. ³⁰

Patients with stroke have less optimal cardiovascular risk factor control compared with patients with coronary artery disease. ³¹ Some have hypothesized that differences in disability between the 2 groups may be associated with their different risk factor control and that such differences may be mediated by clinicians' implicit bias related to disability or perceived treatment goals. ³¹ Although not designed to test those hypotheses, our study shows that among patients with stroke, disability was not significantly associated with risk factor treatment and control. Our findings were different compared with several prior studies, ³ , ⁴ , ⁵ , ⁶ , ⁷ potentially due to differences in the study populations' geographic location, health care systems and practice settings, and definitions of medication adherence (eg, self‐report versus pharmacy claims).

Several limitations existed for this study. First, regarding sampling limitations, more than 10% of survivors of stroke discharged from the hospital were admitted to long‐term care facilities ³² ; individuals who lived in long‐term care facilities were not sampled in NHANES. Therefore, our study findings were not representative of all survivors of stroke. Other limitations inherent to the use of NHANES data exist; for example, blood pressure, hemoglobin A1c, and cholesterol measurements are available for only a subset of NHANES participants and survey question format precluded differentiation between sex and gender. ³³ , ³⁴ Second, definitions of disability varied across clinical, research, and legal settings. Instruments commonly used to assess stroke severity or disability status, such as the modified Rankin scale, were not available in NHANES. Within NHANES, 2 questionnaires ask participants about their disability status. Consistent with prior studies of disabilities among NHANES participants, we used data from the NHANES Physical Functioning Questionnaire and not the NHANES Disability Questionnaire. Vascular risk factor estimates by disability status may vary based on the choice of survey instruments. Third, a respectability bias may have influence participants' self‐report of medication use; a prior study found medication adherence rate was the highest in cases where the rates were assessed through interviews or self‐reports, ³⁵ such as in the case of NHANES. Fourth, NHANES questionnaires did not assess the clinical indications for participants' use of medications. For example, survivors of ischemic stroke with or without hyperlipidemia may have been prescribed high‐intensity statin therapy, which was not directly accounted for in this study's definitions of hyperlipidemia diagnosis, treatment, and control.

Conclusions

In this cross‐sectional nationally representative study of survivors of stroke in the United States, three‐quarters self‐reported a disability. Rates of risk factor treatment and control were suboptimal, and efforts to improve secondary prevention care should target the broader population of survivors of stroke.

Sources of Funding

Tianna Zhou is supported by the Richard K. Gershon, MD, Endowed Medical Student Research Fellowship. Dr de Havenon reports National Institutes of Health/National Institute of Neurological Disorders and Stroke funding (K23NS105924, R01NS130189). Dr Sheth reports National Institutes of Health/National Institute of Neurological Disorders and Stroke funding (U01NS106513, R01NS11072, R01NR018335, R01EB031114, R01MD016178, R03NS112859, U24NS107215, and U24NS107136).

Disclosures

Dr de Havenon has received research funding from the American Academy of Neurology, has received consultant fees from Integra and Novo Nordisk, royalty fees from UpToDate, and has equity in TitinKM and Certus. Dr Sheth reports research grants to Yale from Biogen, Hyperfine and Bard, data and safety monitoring board membership for Zoll, advisory fees from Astrocyte, Rhaeos, and CSL Behring, and equity in Alva Health. Dr Ross currently receives research support through Yale University from Johnson and Johnson to develop methods of clinical trial data sharing, from the Medical Device Innovation Consortium as part of the National Evaluation System for Health Technology, from the Food and Drug Administration for the Yale‐Mayo Clinic Center for Excellence in Regulatory Science and Innovation program (U01FD005938), from the Agency for Healthcare Research and Quality (R01HS022882), from the National Heart, Lung and Blood Institute of the National Institutes of Health (R01HS025164, R01HL144644), and from Arnold Ventures; in addition, Dr Ross was an expert witness at the request of Relator's attorneys, the Greene Law Firm, in a qui tam suit alleging violations of the False Claims Act and Anti‐Kickback Statute against Biogen Inc. that was settled September 2022. Tianna Zhou has no disclosures to report.

Supporting information

Data S1 and S2

Tables S1–S5