Hypothyroidism and Diabetes Results in More Health Care Contact for CVD

Diabetes with comorbid hypothyroidism is associated with increased cardiovascular disease (CVD)-related health care utilization (HCU), according to study results published in the Journal of the Endocrine Society.

Multiple study findings establish a link between thyroid dysfunction and diabetes, and diabetes is a well-established risk factor for CVD. However, the combined effect of diabetes and hypothyroidism on CVD outcomes remains unclear.

Investigators from the University of Chicago sourced data from the Medical Expenditure Panel Survey (MEPS) database, which is a continuous nationally representative survey of individuals in the United States (US). Adults with diabetes who participated in MEPS between 2011 and 2020 were evaluated for CVD-related HCU on the basis of hypothyroidism. To balance for cohort differences, a propensity score matching approach was used.

Among the weighted hypothyroidism (n=1,663,714; median age, 66.0 years) and non-hypothyroidism (n=12,435,990; median age, 62.0 years) cohorts, 68.9% and 46.6% were women (P <.001), 85.3% and 74.0% were White (P <.001), 75.7% and 69.6% had hypertension (P <.001), 71.6% and 60.1% had hyperlipidemia (P <.001), and 7.7% and 3.9% had kidney disease (P <.001), respectively.

In the adjusted analysis, more patients with vs without hypothyroidism had:

• At least 1 visit associated with coronary artery disease (CAD; P =.002) and stroke or transient ischemic attack (TIA; P =.020);
• At least 1 visit with a cardiologist (P =.001), endocrinologist (P =.001), and nephrologist (P =.001); and,
• Prescriptions for anti-hyperlipidemia medications (P =.001), diuretics (P =.001), angiotensin receptor blockers (P =.002), b-blockers (P =.002), and anti-platelet medications (P =.038).

After propensity-score matching, patients with hypothyroidism (n=1585) vs patients without hypothyroidism (n=13,709) had a higher rate of seeing an endocrinologist (18.8% vs 10.0%; P =.001), cardiologist (22.6% vs 19.2%; P =.010), and nephrologist (8.7% vs 6.6%; P =.010) and higher rates of receiving anti-hyperlipidemia medications (70.2% vs 65.1%; P =.001), diuretics (28.8% vs 25.4%; P =.015), b-blockers (34.8% vs 31.6%; P =.030), and sodium-glucose cotransporter-2 (SGLT-2) inhibitors (4.4% vs 3.2%; P =.030), respectively.

Comorbid hypothyroidism was associated with:

• Increased risk for stroke or TIA (adjusted relative risk [aRR], 1.33; 95% CI, 1.07-1.66; P =.025);
• At least 1 visit with an endocrinologist (aRR, 2.01; 95% CI, 1.75-2.31; P =.001), nephrologist (aRR, 1.42; 95% CI, 1.15-1.74; P =.001), and cardiologist (aRR, 1.16; 95% CI, 1.03-1.31; P =.026); and,
• Receipt of SGLT-2 inhibitors (aRR, 1.36; 95% CI, 1.11-1.67; P =.011), diuretics (aRR, 1.14; 95% CI, 1.03-1.26; P =.025), b-blockers (aRR, 1.12; 95% CI, 1.02-1.22; P =.026), and anti-hyperlipidemia medications (aRR, 1.08; 95% CI, 1.04-1.13; P =001).

In a non-diabetes cohort, hypothyroidism was associated with increased HCU for heart failure (aRR, 1.41; 95% CI, 1.12-1.77; P =.007) and CAD (aRR, 1.14; 95% CI, 1.02-1.26; P =.028).

The main study limitation was the inability to assess causal relationships due to the cross-sectional nature.

The study authors concluded, “[I]n this study, we found that treated [hypothyroidism] is associated with excess CVD-related care utilization in US adults with [diabetes] even after covariate balancing. The presence of [diabetes] could pose challenges for the management of [hypothyroidism], potentially leading to both over- and undertreatment of [hypothyroidism], which could contribute to increased CVD risk in individuals with [diabetes].”

Disclosure: One study author declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.