Many older Medicare beneficiaries with incident epilepsy have pre-existing chronic conditions, especially stroke, developmental and substance use disorders, and neurologic, congenital, and psychiatric problems, according to a claims-based study published in Epilepsia .

“Compared [with] epilepsy-free Medicare beneficiaries, those with incident epilepsy in 2019 had a higher prevalence of most pre-existing chronic conditions,” Siran M. Koroukian, PhD, and colleagues wrote.

The incidence of epilepsy increases after 50 years of age and peaks at 75 years of age and older, reaching an incidence of up to 247 per 100,000. It is the third most common neurological disorder in adults aged 65 and older, according to Dr. Koroukian and colleagues. As people with epilepsy age, they are more likely to have chronic conditions that can complicate their care. Stroke represents the most common cause of epilepsy among older adults, according to the study results.

Most prior research examining comorbid chronic conditions in older adults with epilepsy has focused on prevalent epilepsy, but fewer have investigated more than several comorbidities in patients with incident (new onset) epilepsy.

Dr. Koroukian and colleagues conducted a retrospective cohort study of epilepsy incidence in 2019 using a random sample of 4.99 million fee-for-service Medicare beneficiaries aged 65 years and older. They used the 2016-2018 Medicare Beneficiary Summary File (MBSF), which includes one record per individual per year with information about demographics and summary indicators for 30 chronic conditions and 37 potentially disabling conditions recorded in claims.

They identified pre-existing chronic conditions from the 2016–2018 MBSF and compared chronic condition prevalence between Medicare beneficiaries who had epilepsy in 2019 with those who did not. They analyzed variations in pre-existing excess chronic condition prevalence by age, sex, and race or ethnicity, adjusting for oversampling of Non-Hispanic Black and Hispanic beneficiaries.

All Chronic Conditions More Common in Epilepsy

In the full study sample of 4.99 million patients, the mean age was 77.5 years, 55.0% were women, and 77.4% were White. The sample included 20,545 older adults with incident epilepsy. These patients were generally older than those without epilepsy (>60% aged 75 and older).

The researchers also found that incident epilepsy status “differed markedly by race/ethnicity (P<0.001).” Dr. Koroukian and colleagues reported a higher percentage of Black beneficiaries in the group with versus without incident epilepsy (16.9% vs 9.8%), and Non-Hispanic White and other race beneficiaries were less represented among those with versus without incident epilepsy (71.5% vs 77.4% and 4.5% vs 5.9%, respectively).

Beneficiaries with incident epilepsy had higher prevalences of all 14 pre-existing chronic con – dition categories investigated compared with -epilepsy-free counterparts, with especially dis – proportionate excess prevalences of stroke, developmental, neurologic, and substance use disorders, and congenital and psychiatric conditions.

❯ Medicare beneficiaries with incident epilepsy had 4.82 times the stroke prevalence as those without epilepsy (adjusted prevalence rate ratio [APRR] for stroke, 4.82; 99% CI, 4.60-5.04).

❯ Beneficiaries with incident epilepsy had high – er prevalences of pre-existing developmental conditions (APRR, 4.64; 99% CI, 4.09-5.19), neurological conditions (APRR, 3.17; 99% CI, 3.08-3.27), substance use disorders (APRR, 3.00; 99% CI, 2.81-3.19), congenital condi – tions (APRR, 2.47; 99% CI, 2.15-2.78), and psychiatric disorders (APRR, 1.98; 99% CI, 1.94-2.01).

❯ For most documented chronic conditions, excess prevalence among beneficiaries with incident epilepsy was greater for those who were younger and those who were Hispanic.

Clinical Implications & Directions for Future Research

“Our findings have important clinical implications given the high burden of pre-existing, and potentially co-occurring, chronic conditions in older adults with incident epilepsy,” Dr. Koroukian and colleagues wrote. “This calls for a multidisciplinary approach to their care, including attending to their metabolic and cardiovascular health, both preventively and curatively.”

The researchers also pointed to specific clinical implications, including closer surveillance of patients with non-neurological conditions, as well as the need for multidisciplinary care, particularly because comorbidities are associated with greater risks related to mortality, functional status, QOL, and healthcare utilization.

“Nearly 80% of medical costs are related to the management of comorbid conditions, rather than that of epilepsy,” Dr. Koroukian and colleagues noted. “For researchers, the findings call for the analysis of constellations of pre-existing conditions to further elucidate shared pathophysiology and identify opportunities for prevention.”