Women Less Likely Than Men to Adhere to Post-ACS Medications: TEXTMEDS

Significant disparities exist in the control of cardiovascular risk factors, as well as in medication adherence, between men and women who have had acute coronary syndromes, an analysis from the TEXTMEDS study shows.

Twelve months after ACS, women were less likely than men to achieve the recommended LDL-cholesterol target of less than 1.8 mmol/L (< 70 mg/dL) and to meet the goals for regular physical activity, although women were more likely to achieve a healthy body mass index,

When it came to medication, women were also less likely than men to adhere to the recommended therapies, such as statins, beta-blockers, aspirin, ACE inhibitors or ARBs, and P2Y12 inhibitors, investigators report in Open Heart.

“Medical adherence is important and difficult to achieve for many patients, and even more so for women compared to men,” senior investigator Clara Chow, MBBS, PhD (University of Sydney and George Institute for Global Health, Australia), told TCTMD. “We should always be asking about medical adherence after ACS, especially among our patients with socioeconomic barriers to care, and discussing with them how we can help them be medically adherent post-ACS.”

Several studies have shown that adherence to medical therapy is suboptimal after ACS, and multiple others have revealed that women are less likely than men to be treated with guideline-directed medical therapy (GDMT) in this setting, said Chow. The Australian researchers have also previously shown not only are women with STEMI less likely than men to undergo revascularization, but also they’re less likely to receive secondary medications upon discharge.

Medical adherence is important and difficult to achieve for many patients, and even more so for women compared to men. Clara Chow

The TEXTMEDS study was a randomized, clinical trial conducted in urban and rural centers throughout Australia with the aim of using text messages to improve medication use after ACS. As reported previously, patients who received the text messages weren’t more likely to take their medications than those treated with usual care, but investigators did see positive changes in some lifestyle factors.

The secondary analysis investigated differences in risk-factor control and medication adherence by sex in 1,379 participants (average age 58.5 years; 20.6% women). Self-reported medication adherence, the study’s primary endpoint, was defined as taking more than 80% of up to five cardioprotective drugs. On average, patients were taking 6.3 medications for various comorbidities.

At 12 months, 73.2% of males achieved a target blood pressure of less than 140/90 mm Hg compared with 70.0% of females. While a little less than 50% of men achieved the optimal LDL goal compared with 39.2% of women, 26.2% of females had a healthy BMI, defined as < 25 kg/m², compared with 20.1% of males. More than 63% of the male patients met the target for regular physical activity versus just 50.4% of females. More women than men reported being current smokers (19.4% vs 15.3%).

Medication adherence in the overall cohort at 6 and 12 months was 52.3%, with 53.9% of males reporting being adherent to all five medications compared with 46.1% of females (P = 0.02).

In a model adjusted only for age and ethnicity, the likelihood of adherence in women was lower than in men (OR 0.73; 95% CI 0.56-0.95). The association remained significant after adjusting for clinical factors but lost statistical significance after adjusting for socioeconomic variables. In the fully adjusted model, women were only less likely to be adherent to statin therapy (OR 0.37; 95% CI 0.19-0.76).

“When we accounted for socioeconomic factors like income and education, the difference between men and women largely disappeared, suggesting socioeconomic factors explain this relationship to some extent,” lead investigator Shiva Raj Mishra, PhD (University of Sydney), told TCTMD. “We need more research in this area to untangle this.”

Combined with lower physical activity levels, the lower adherence to statins among women could help explain why they were less likely to get to the cholesterol target of < 1.8 mmol/L, say the researchers. As for why women were less likely to take statins, they can only speculate, noting it could be related to concerns about side effects, a perception of lower cardiovascular risk, psychosocial barriers, and gender norms and competing priorities, such as caregiving roles.

Another finding from TEXTMEDS is that the more comorbidities the patient had, the less likely they were to be adherent to the cardioprotective medications. “With more conditions a patient is managing simultaneously, it could be harder to keep with a complex medication regimen,” said Mishra.

He added that the medical adherence rate at 6 and 12 months is low, but not surprising. “Adherence is shaped by health literacy, access to follow-up care, and socioeconomic circumstances,” he said. “Just knowing and having a serious cardiac event alone is clearly not sufficient as an intervention, and more is needed to address this.”