Background
To compare the estimated 10- and 30-year cardiovascular risk in primary care patients with and without serious mental illness (SMI; bipolar disorder, schizophrenia, or schizoaffective disorder).
Methods and Results
All patients aged 18 to 75 years with a primary care visit in January 2016 to September 2018 were included and grouped into those with and without SMI using diagnosis codes.
Ten-year cardiovascular risk was calculated using atherosclerotic cardiovascular disease scores for patients aged 40 to 75 years without cardiovascular disease; Thirty-year cardiovascular risk was estimated using Framingham risk scores for patients aged 18 to 59 years without cardiovascular disease.
Demographic, vital signs, medication, diagnosis, and health insurance data were collected from the electronic medical record by a clinical decision support system. Descriptive statistics examined unadjusted differences, while general linear models examined differences for continuous variables and logistic regression models for categorical variables.
Models were then adjusted for age, sex, race, ethnicity, and insurance type. A total of 11,333 patients with SMI and 579,924 patients without SMI were included. After covariate adjustment, 10-year cardiovascular risk was significantly higher in patients with SMI (mean, 9.44%; 95% CI, 9.29–9.60%) compared with patients without SMI (mean, 7 .99%; 95% CI, 7.97–8.02).
Similarly, 30-year cardiovascular risk was significantly higher in those with SMI (25% of patients with SMI in the highest risk group compared with 11% of patients without SMI; P < 0.001).
The individual cardiovascular risk factors that contributed the most to increased risk for people with SMI were high body mass index and smoking. Among SMI subtypes, patients with bipolar disorder had the highest 10-year cardiovascular risk, while patients with schizoaffective disorder had the highest 30-year cardiovascular risk.
Conclusions
The significantly increased cardiovascular risk associated with SMI is evident even in young adults. This suggests the importance of addressing major uncontrolled cardiovascular risk factors in people with SMI at the earliest possible age.
Clinical Perspective What’s new? Adults of all ages with serious mental illnesses (bipolar disorder, schizophrenia, or schizoaffective disorder) had a significantly increased cardiovascular risk compared to their peers. What are the clinical implications? It is important to address major uncontrolled cardiovascular risk factors in people with serious mental illness at as early an age as possible to reduce morbidity and mortality in this population. |
Comments
This new study investigated cardiovascular disease (CVD) risk outcomes among patients with serious mental illness (SMI) attending primary care clinics that were part of HealthPartners and Park Nicollet in Minnesota and Wisconsin.
With their study finding that the presence of serious mental illness (SMI) likely increases the risk of cardiovascular disease (CVD), researchers at the University of Minnesota School of Medicine emphasize the importance to address the main cardiovascular risk factors as soon as possible.
Doing so can help reduce both morbidity and mortality in patients with SMI, including bipolar disorder, schizophrenia, or schizoaffective disorder, they emphasized.
This research was recently published online in the Journal of the American Heart Association, and researchers used diagnosis codes to differentiate patients with and without SMI who had a primary care visit between January 20, 2016 and September 19 of 2018.
“Some studies have examined estimates of cardiovascular risk in people with and without SMI, but most have used control populations from separate studies or estimates from the general population. “This approach is suboptimal,” the authors noted. "As part of a cluster-randomized trial aimed at reducing CV risk in patients with SMI, we collected baseline CV risk estimates for patients with and without SMI from the same clinical populations."
From their final analysis that included 11,333 patients with SMI and 579,924 who did not have SMI, adjusting for demographic data, vital signs, medication, diagnosis, and health insurance, they showed that there is a higher 10-year mean incidence of CVD among patients with SMI compared to those without SMI:
- Patients with SMI: 9.44% (95% CI, 9.29%-9.60%)
- Patients without SMI: 7.99% (95% CI, 7.97%-8.02%)
Individuals in the SMI group had to have at least 2 outpatient or at least 1 inpatient SMI diagnosis code in the 2 years prior to study inclusion in their electronic medical record, and CV risk was measured. estimated using the atherosclerotic cardiovascular disease (ASCVD) risk score (ages 40-75 years) for those with a diagnosis of ASCVD and Framingham risk score (ages 18-59 years) for those without a diagnosis of ASCVD.
The most common SMD was bipolar disorder (70.6%), followed by schizoaffective disorder (17.6%) and schizophrenia (11.7%). Patients with any SMI vs. no SMI were also more likely to be younger (<65 years; 90.8% vs. 86.8%); self-identifying as Black (13.6% vs. 9.3%), American Indian/Alaska Native (0.8% vs. 0.36%), or multiple races (0.9% vs. 0.4%); and have Medicaid (26.7% vs. 11.8%) or Medicare (10.7% vs. 8.5%) coverage.
While the 10-year risk was nearly equal between the SMI and non-SMI cohorts (8.0% vs. 7.9%), respectively, the 30-year risk was significantly higher in the latter, as shown below:
- More patients with SMI had a diagnosis of CVD, coronary heart disease, or hypertension, respectively: 4.6% vs. 3.7% (P < 0.0001), 3.0% vs. 2.6% (P = 0.015) and 14.9% versus 13.2% (P < .0001).
- More patients with SMI were likely to be classified as overweight or obese: 77.9% vs. 68.8% (p < 0.0001).
- More patients with SMD were active smokers: 36.2% vs 12.1% (p < 0.0001)
A multivariate model that adjusted for age, race, ethnicity, sex, and insurance status demonstrated similar findings. Patients with SMI still had higher 10-year risks of ASCVD (8.31% vs. 7.92%) and 92% (HR, 1.92; 95% CI, 1.82-2.01; P < 0.0001) increased risk of “being in a risk group compared to patients without SMI,” the authors noted.
Taking into account the risk attributable to each SMI diagnosis covered by this study, the highest 10-year unadjusted CVD risk was observed among people with schizophrenia and the lowest was bipolar disorder. In contrast, the highest 10-year adjusted risk was seen among people with bipolar disorder and the highest 30-year risk was seen among people with schizoaffective disorder.
Age was shown to have the greatest influence on 10-year risk, such that younger ages had an increased risk of CVD, while adjustment for insurance status showed a decreased risk.
“The significantly increased cardiovascular risk associated with SMI is evident even in young adults,” the study authors emphasized. "This suggests the importance of addressing major uncontrolled cardiovascular risk factors in people with SMI at as early an age as possible."
Strengths of their findings include that their research is the first to estimate lifetime CVD risk in a large sample of outpatients with SMI, that the risk differences are so significant compared to people who do not have a diagnosis of SMI. SMI, and its use of the same study sample for patients with and without SMI. The main limitation in generalizing their conclusions to a broader patient population is that they conducted their study within an integrated healthcare system.
