Introduction

High blood pressure (HBP) is clinically defined as a systolic pressure of ≥140 mmHg or a diastolic pressure of ≥90 mmHg and is a primary risk factor for cardiovascular, renal, and other chronic diseases.¹ Globally, the World Health Organization (WHO) estimates that 1.28 billion adults aged 30 to 79 have hypertension, with the highest burden in low- and middle-income countries.² In Peru, an estimated 5.5 million people over the age of 15 have high blood pressure, representing 22.1% of the population;³ with a higher prevalence in urban areas.⁴ Among older adults, 35.3% of individuals aged 60 or older were found to have hypertension.⁴ Therefore, it is essential to implement effective strategies for the prevention, detection, and management of high blood pressure, particularly in vulnerable populations such as older adults.

A critical factor in hypertension management is poor adherence to treatment, which worsens clinical outcomes and places additional strain on healthcare systems.⁵ It is estimated that 85% of patients do not follow their medication regimen correctly, primarily due to forgetfulness (48.2%), although other barriers such as cost, side effects, and lack of time also contribute.⁶ Although 80% of patients are aware of the risks associated with poorly controlled hypertension, such as strokes and heart disease, most seek medical attention only when symptoms appear.⁷ Furthermore, 94% of patients do not follow medical recommendations for regular check-ups, reflecting a mistaken belief about a cure.⁸

Non-adherence to antihypertensive treatment is a multifactorial issue influenced by various sociodemographic and economic factors. Among the key determinants identified in the literature, sex significantly impacts treatment adherence, with studies indicating that men are less likely to follow medical recommendations than women.^9–11 For example, a study by Williams et al¹² found that men exhibited lower adherence compared to women. This difference may be attributed to health behavior patterns, as men tend to seek medical attention less frequently and underestimate the perceived risk of chronic diseases such as hypertension.¹³ On the other hand, women tend to take a more active role in self-care and health management, which may explain their higher adherence rates.¹⁴ However, it is important to note that these differences are not consistent across all studies. For example, a systematic review with meta-analysis found no significant differences in adherence to antihypertensive medication between sexes; in fact, the study reported lower self-reported adherence among women.¹⁵

Marital status has also been identified as a key factor in treatment adherence. Previous studies have shown that individuals who are married or living with a partner have higher rates of therapeutic adherence compared to those who are single, widowed, or divorced.^16,17 A study of 2,122 older adults found that unmarried men had lower adherence compared to those who were married.¹² Another study also reported that divorced or separated patients had the highest risk of non-adherence, suggesting that the dissolution of a relationship may negatively impact treatment management.¹⁸ This finding is attributed to the emotional and practical support provided by a partner in disease management, such as medication reminders and accompaniment to medical appointments.¹⁹ In contrast, single older adults may experience greater social isolation and less supervision in treatment adherence, contributing to higher rates of non-adherence.²⁰ However, studies have reported that married patients may also be at a higher risk of non-adherence, possibly due to family dynamics that interfere with treatment follow-up.¹⁸ Regardless, these findings emphasize the importance of considering marital status as a key factor in designing strategies to improve adherence among hypertensive patients.

Educational level is another key determinant of adherence to antihypertensive treatment. The literature suggests that patients with lower education levels struggle to understand the importance of treatment, interpret medical instructions, and properly manage their medication.²¹ Low health literacy can impair patients’ ability to follow medical recommendations and adopt healthy habits that support pharmacological treatment.¹⁶ This issue is particularly relevant for older adults living in poverty, where access to health information is often limited.

From an economic perspective, income and access to social security significantly influence treatment adherence. Patients with lower incomes often struggle to afford medication, doctor’s appointments, and transportation to health centers, which may result in treatment interruptions.²² In many low- and middle-income countries, including Peru, unequal access to healthcare services creates additional barriers for older adults, who rely on social assistance programs such as “Pension 65” to meet their basic needs.^23,24 Similarly, the lack of financial support from family members or the state can lead to financial stress, affecting the prioritization of healthcare expenses and, consequently, adherence to antihypertensive treatment.²⁵

Hypertension is a major public health concern, particularly among older adults, who face a higher risk of cardiovascular complications and other comorbidities associated with inadequate blood pressure control. Adherence to antihypertensive treatment is essential for preventing adverse outcomes. In this context, older adults benefiting from the “Pension 65” program—a Peruvian government initiative that provides financial support to individuals aged 65 and older living in extreme poverty—represent a particularly vulnerable group.^26,27 In addition to the challenges of aging, this population has limited access to medication, healthcare services, and social support networks, which may impact their adherence to treatment.

On the other hand, in Peru, there is limited information on the relationship between socioeconomic conditions and adherence to antihypertensive treatment among older adults. Most studies on adherence to chronic treatments have focused on the general population or patients receiving care in urban centers with greater access to healthcare services. However, there is a gap in the literature regarding how vulnerability factors—such as low educational attainment, lack of stable income, and limited access to healthcare—impact therapeutic adherence among older adults living in extreme poverty. Since the “Pension 65” program serves a population with distinct socioeconomic characteristics, it is essential to generate specific evidence to better understand the factors influencing non-adherence to treatment and its impact on beneficiaries’ health.

Therefore, this study aimed to identify the socioeconomic factors associated with non-adherence to antihypertensive treatment among older adults enrolled in the “Pension 65” program in Peru, building on prior evidence about how these factors influence adherence in older adults globally. By focusing on a particularly vulnerable group within the Peruvian context, this study contributes to filling a gap in the literature and supports the development of tailored interventions for improving treatment outcomes in low-income elderly populations.

Material and Methods

Study Design and Participants

A cross-sectional and analytical study was conducted among older adults enrolled in the “Pension 65” program in Peru. The sample was drawn from the city of Chiclayo, located in the Lambayeque region, with the support of local health personnel and community leaders. According to the available records, a total of 600 older adults affiliated with “Pension 65” in Chiclayo were identified as having a diagnosis of hypertension. From this group, 132 individuals were approached and invited to participate. After excluding those who did not sign the informed consent (n = 10) and those with incomplete or invalid data (n = 14), the final sample consisted of 108 participants, resulting in a response rate of approximately 81.8% (Figure 1).

Figure 1 Study Design.

Participants were selected through non-probabilistic convenience sampling. Although the National “Pension 65” Program serves 824,351 users nationwide,²⁸ disaggregated national data on beneficiaries diagnosed with hypertension was not available at the time of data collection. Therefore, the study focused on accessible and eligible individuals within the Chiclayo area.

Inclusion criteria were: being aged 65 or older, being a registered “Pension 65” beneficiary, having a medical diagnosis of hypertension, and providing informed consent. The exclusion criteria, established prior to data collection, were applied during recruitment and data processing. Participants were excluded if they (a) had not attended the program in the past year (based on program records), (b) could not be contacted due to a changed or non-functioning telephone number, (c) were temporarily residing outside the jurisdiction, or (d) did not complete the questionnaire.

Regarding sample size, we used Soper’s Free Statistical Calculator (version 4.0)²⁹ to estimate the minimum required sample size for a multiple regression analysis. Based on an expected effect size of 0.35, power of 0.80, ten explanatory variables, and an alpha level of 0.05, the minimum required sample size was calculated to be 54 participants. A total of 108 older adults voluntarily participated, exceeding the required sample size.

Ethical Aspects

Data collection was conducted following the approval of the research project by the Faculty of Health Sciences at Señor de Sipán University (Resolution No. 0369–2022/FCS-USS). Subsequently, authorization was requested from the administrator of the Pension 65 program to access user data (Approval No. D000001-2024-MIDIS/P65-UT Lambayeque). Once authorization was obtained, participants were contacted and informed about the study’s objectives and procedures. Voluntary participation was ensured through the signing of an informed consent form by each older adult, guaranteeing anonymity and confidentiality in data handling. The study adhered to the ethical principles of respect, beneficence, and justice, in accordance with the Declaration of Helsinki and current ethical standards.

Study Variables

Sociodemographic and Economic Factors

To assess the sociodemographic and economic factors associated with non-adherence to antihypertensive treatment in older adults, we used the Questionnaire for the Evaluation of Socioeconomic Factors Associated with Non-Adherence to Treatment in Hypertensive Persons. This instrument included 44 closed-ended items that collected information on personal and contextual characteristics such as gender, age, marital status, education, employment status, income, and type of health insurance. The instrument’s content validity was confirmed by five experts, yielding a validity coefficient of 0.965 using Aiken’s V. Reliability was assessed using Cronbach’s alpha, with values ranging from 0.79 to 0.85, indicating high internal consistency.

Non-Adherence to Antihypertensive Treatment

Adherence to antihypertensive treatment was evaluated using the Morisky-Green test, a validated four-item questionnaire with dichotomous (yes/no) responses, widely employed to assess therapeutic adherence in patients with chronic conditions.³⁰ This tool has been extensively applied in both clinical and community-based settings, including among older adults with hypertension.³¹ Notably, its use has also been documented in the Peruvian context, such as in the study by Carhuallanqui et al.³²

Statistical Analysis

Descriptive statistics and association tests were used for data analysis. Initially, a descriptive analysis of sociodemographic and economic variables was performed using absolute and relative frequencies, and measures of central tendency and dispersion for quantitative variables. To assess associations between independent variables and non-adherence to antihypertensive treatment, chi-square tests were used in the bivariate analysis. Subsequently, a binary logistic regression model was conducted to identify factors independently associated with non-adherence, calculating adjusted odds ratios (OR) and 95% confidence intervals (CI). Statistical significance was set at a p-value of < 0.05. All analyses were performed using SPSS version 26.

Results

Table 1 presents the sociodemographic and insurance characteristics of the 108 older adults participating in the study. Most participants were between 65 and 75 years old and the majority were male. A large proportion were affiliated with the SIS health insurance system, and over half reported non-adherence to antihypertensive treatment.

Table 1 Characteristics of the “Pension 65” Affiliates (N=108)

Table 2 shows that males are significantly more likely to be non-compliant with treatment than females (p = 0.036). Similarly, affiliation with SIS showed a strong association with non-adherence (p = 0.000). Marital status was also a significant factor (p = 0.011). Regarding educational level, a statistically significant difference was observed (p = 0.049). Regarding economic factors, having previously worked in self-employed occupations was associated with a higher likelihood of non-adherence (p = 0.020). Furthermore, older adults with a monthly income below $120 had a higher rate of non-adherence (p = 0.001). Finally, the lack of financial resources was also associated with a higher rate of non-adherence to treatment (p = 0.002).

Table 2 The Variables Studied According to Non-Adherence to Antihypertensive Treatment

Table 3 presents the factors associated with non-adherence to antihypertensive treatment among “Pension 65” affiliates. Several statistically significant variables were identified, with being male showing the strongest association with non-adherence (OR = 28.334, 95% CI: 5.359–149.794, p = 0.000), followed by being single (OR = 10.960, 95% CI: 2.501–48.035, p = 0.001), having incomplete primary education (OR = 7.785, 95% CI: 1.986–30.512, p = 0.003), previous formal employment (OR = 4.352, 95% CI: 1.601–11.829, p = 0.004), and having an income below $120 (OR = 8.768, 95% CI: 2.158–35.622, p = 0.002). It was also observed that not receiving financial support was significantly associated with non-adherence (OR = 3.207, 95% CI: 1.104–9.315, p = 0.032), as was having SIS insurance (OR = 25.305, 95% CI: 5.352–119.652, p = 0.000). In contrast, normal WC, age, and BMI did not show statistically significant associations.

Table 3 Factors Associated with Non-Adherence to Antihypertensive Treatment Among Pension 65 Affiliates

Discussion

High blood pressure is a major risk factor for the development of cardiovascular diseases, which are among the leading causes of mortality in older adults.³³ Antihypertensive treatment, which includes medication and lifestyle modifications, is essential for controlling blood pressure and preventing serious complications.³⁴ However, adherence to this treatment remains a challenge, particularly among vulnerable populations such as older adults.³⁵ In Peru, the “Pension 65” program provides financial support to older adults living in extreme poverty.^27,36 Despite this support, socioeconomic barriers may still affect adherence to antihypertensive treatment. This study aims to identify and analyze the socioeconomic factors associated with non-adherence to treatment in this population, with the goal of developing strategies to improve adherence and, consequently, the health of “Pension 65” affiliates. In the current study, the main findings indicate that non-adherence to antihypertensive treatment is significantly associated with various socioeconomic factors.

Sex

Specifically, men were more likely to be non-adherent to antihypertensive treatment compared to women. This finding aligns with previous research indicating that men tend to have lower adherence rates to chronic treatments, including antihypertensive therapy.¹⁰ Studies conducted in various countries have shown that men are less likely to adhere to medical recommendations, which may be influenced by perceptions of self-sufficiency or a lower concern for their health compared to women.^9–11 However, a systematic review with meta-analysis found no significant differences in adherence to antihypertensive medication between sexes; in fact, the study reported lower self-reported adherence among women.¹⁵ Regardless, the differences observed in our study may be exacerbated by cultural and social factors specific to the Peruvian context, where traditional gender roles tend to place greater responsibility on women for family health care, while men may downplay the need for medical treatment.³⁷

Furthermore, men’s lack of adherence may be linked to barriers in accessing healthcare services, as they tend to seek medical attention less frequently than women, delaying the monitoring of chronic conditions such as hypertension.¹³ This is especially relevant in vulnerable populations, such as those affiliated with the “Pension 65” program, who face economic and logistical challenges that further hinder access to healthcare services.^27,36 The perception of invulnerability, combined with the lack of an adequate support network, may contribute to men’s reluctance to strictly follow prescribed treatments.³⁸ These factors highlight the need for interventions aimed at improving treatment adherence among men by addressing both cultural and structural barriers within the Peruvian healthcare system.

Marital Status

Additionally, our study found that being single was associated with a higher likelihood of non-adherence to antihypertensive treatment. Similarly, other studies have reported that marital status plays a significant role in adherence to chronic disease treatments. Findings from a study on the US population suggest that married individuals tend to have higher adherence rates to treatment,¹⁶ likely due to the presence of an emotional and social support network, typically led by their partner, which facilitates adherence to medical instructions.¹⁷ Having a spouse may provide constant reminders to take medication, support for attending medical appointments, and assistance in adopting lifestyle changes that enhance therapeutic adherence.¹⁹ However, inconsistencies exist in these associations. For example, a study by Abbas et al¹⁸ found that married individuals were more likely to be non-adherent to antihypertensive treatment.

In the Peruvian context, these differences may be even more pronounced. In many Latin American cultures, including Peru, family support plays a fundamental role in health management, and single individuals or those without a stable partner may lack the same level of support as married individuals.³⁹ This issue is exacerbated in the most vulnerable populations, such as affiliates of the “Pension 65” program, who may live alone and have limited access to social or family support networks.⁴⁰ This not only reduces the likelihood of proper treatment follow-up but also increases feelings of isolation, which may negatively impact motivation to adhere to the therapeutic regimen.⁴¹ On the other hand, stress management and daily responsibilities are additional factors that may explain this association. Single individuals, particularly those of advanced age, may experience higher stress levels due to loneliness and lack of emotional support, which can result in lower adherence to treatment.⁴² In comparison, individuals who are married or living with a partner may have greater emotional and practical resources to manage the demands of hypertension and the complexities of treatment, leading to higher adherence rates.^42,43 This finding underscores the importance of social and family networks in promoting treatment adherence among older adults living alone.

Educational and Economic Factors

Another key finding of this study is that having less than a primary school education is associated with non-adherence to antihypertensive treatment. Our results align with previous studies, which have consistently shown that lower educational levels are linked to reduced adherence to treatments for various diseases. It has also been noted that individuals with lower educational levels or limited health literacy tend to have restricted access to health-related information, making it difficult for them to understand medical instructions and the importance of adhering to long-term treatment.^44,45 A study by Farah et al²¹ found that a higher level of education was significantly associated with increased adherence to hypertension medication. This lack of knowledge and understanding may lead patients to underestimate the severity of hypertension, resulting in non-adherence to treatment.

Older adults who did not complete primary education have likely faced economic and social barriers throughout their lives, which may limit their access to quality healthcare resources and their understanding of the risks associated with non-adherence to antihypertensive treatment.⁴⁶ Furthermore, a low level of education may be associated with limited access to the healthcare system, making individuals less likely to attend regular medical check-ups or seek assistance when they do not understand their doctor’s instructions.⁴⁷ A low level of education can also impact risk perception and health self-management.⁴⁸ Patients with limited primary education may have lower health literacy, which can impact their ability to interpret medication labels, follow instructions, or understand the importance of adhering to a continuous treatment regimen.⁴⁵ Older adults enrolled in the Pension 65 program, who rely on social assistance for their livelihood, may have limited access to health education programs that could help them effectively manage their condition.⁴⁰

Another possible explanation for this finding is that individuals with lower education levels often face economic and employment disadvantages, making them more likely to hold informal, unstable, or low-income jobs. This, in turn, limits their ability to consistently afford necessary medications. These economic and logistical challenges can hinder consistent access to necessary treatments, ultimately compromising therapeutic adherence.⁴⁹ In the case of older adults in Peru, this issue is particularly critical, as these limitations are further exacerbated by the inadequate health infrastructure in rural areas, where many of them reside, making access to medical care even more challenging.²⁴

In our study, we found that older adults who had never held formal employment, those with an income of less than 450 soles (approximately 120 dollars), and those who did not receive any form of financial support were more likely to discontinue their antihypertensive treatment. These factors further support the idea that economic insecurity, combined with a lack of formal education, can hinder individuals’ ability to effectively manage their health—whether due to difficulties in accessing medication or a lack of awareness about the importance of adhering to treatment.^24,46–48

Furthermore, the combination of low income and lack of financial support may lead to greater reliance on social programs such as “Pension 65.” While these programs are essential for improving the quality of life of older adults in extreme poverty, their benefits may be insufficient to fully cover the costs of long-term treatment for chronic conditions. This underscores the need to complement such programs with interventions that enhance both health education and access to medical resources, particularly among populations with low levels of formal education.

Type of Social Insurance

Finally, we found that older adults enrolled in the Comprehensive Health Insurance (SIS) were more likely to report non-compliance with antihypertensive treatment compared to those covered by the EsSalud system. This finding aligns with previous studies that have highlighted the limitations of the SIS in terms of coverage and access to healthcare services.^26,27 The SIS, primarily designed for individuals in extreme poverty, provides more limited coverage compared to EsSalud. This could impact treatment adherence, particularly when continuous access to medications and medical consultations is necessary.²³ In fact, despite its own challenges, EsSalud generally provides more comprehensive care, which may contribute to higher treatment adherence rates among its beneficiaries.²⁷

These findings may be attributed to several factors. On one hand, SIS beneficiaries often encounter greater barriers to accessing healthcare, including limited availability of medications and inadequate infrastructure in rural areas, where many “Pension 65” program affiliates reside.^27,50 In comparison, EsSalud has a broader network of healthcare centers and a greater availability of essential medications, making it easier to ensure continuous monitoring of antihypertensive treatment.²⁶ The lack of timely access to medical resources within the SIS can lead to frustration and demotivation among patients, increasing the likelihood of non-compliance with treatment. Additionally, the care provided to SIS beneficiaries is often less personalized and more overcrowded, which can limit both the time and quality of doctor-patient interactions.⁵⁰ This situation may result in older adults receiving insufficient guidance on the importance of treatment adherence and the risks of uncontrolled hypertension, ultimately reducing their likelihood of compliance.⁵¹

Another possible explanation for this finding is that SIS beneficiaries, due to their more vulnerable socioeconomic status, may prioritize other essential expenses over purchasing medications or covering transportation costs to healthcare centers, particularly if these facilities are located far from their homes. This contrasts with EsSalud affiliates, who, while they may also experience financial difficulties, generally have a more stable support network and better access to healthcare resources.

Limitations and Future Perspectives

This study has certain limitations that should be considered when interpreting the results. First, the cross-sectional design prevents the establishment of definitive causal relationships between socioeconomic factors and non-adherence to antihypertensive treatment. This limitation restricts our ability to determine whether the identified factors directly cause non-compliance or if they are influenced by other unexamined variables. Therefore, future research could benefit from longitudinal designs to assess how these factors evolve over time and their impact on treatment adherence.

Another limitation is that the study relies on self-reported data on treatment adherence, which may be affected by recall bias and social desirability bias, particularly in an older adult population. Incorporating objective measures, such as tracking medication refills or assessing blood pressure control biomarkers, could enhance the accuracy and reliability of the findings. Additionally, the use of a non-probabilistic convenience sampling method may limit the representativeness of the findings and introduce potential selection bias. The results, therefore, may not be generalizable to the entire population of older adults in Peru. Future research should consider using probabilistic sampling methods to improve external validity and reduce the risk of bias.

Furthermore, this study focused exclusively on a sample of “Pension 65” program affiliates in Peru, which limits the generalizability of the findings to other older adult populations in the country. Future research could include broader and more diverse samples to determine whether these results hold across different demographic groups. Therefore, it would be valuable to explore how targeted interventions, such as health education programs and social support initiatives, could enhance adherence to antihypertensive treatment in this population. It is also recommended to explore the impact of additional factors, such as mental health status and access to community support networks, which may play a significant role in treatment adherence. Such research could contribute to the development of effective health policies tailored to the needs of older adults, aiming to reduce the burden of hypertension and its associated complications in the Peruvian population.

Public Health Implications

The findings of this study underscore the need for targeted interventions to enhance adherence to antihypertensive treatment among low-income older adults in Peru. Socioeconomic factors associated with non-adherence to treatment—such as being male, single, having a low level of education, and lacking coverage under the SIS—underscore the need to tailor public health strategies to address both individual and structural barriers affecting this vulnerable population. Therefore, the implementation of health education programs aimed at enhancing awareness of hypertension and the importance of treatment adherence is recommended, particularly for individuals with lower levels of education. This could involve targeted awareness campaigns for beneficiaries of social programs like “Pension 65”, using clear, accessible language and providing practical guidance on treatment adherence. Additionally, strengthening the role of primary care in delivering personalized and continuous education is essential, particularly for SIS affiliates, where resources and infrastructure may be more limited.

Similarly, the study highlights the need for social support policies that provide assistance and establish support networks for single older adults and those without family support, as these networks could play a decisive role in improving treatment adherence. Interventions such as home visits, telephone follow-ups, and community programs could enhance adherence in these groups by providing reminders, emotional support, and easier access to medical services. Finally, improving the infrastructure and resources available to SIS beneficiaries, particularly in rural areas, is essential to ensuring equitable access to healthcare and sustained treatment adherence. Strengthening the healthcare system in these areas would help reduce disparities in access to medications and medical services, thereby fostering sustained adherence to antihypertensive treatment.

Finally, it is essential to raise awareness among healthcare professionals who care for this vulnerable group of older adults so they can develop targeted strategies for monitoring treatment and enhancing therapeutic adherence in this population. This is particularly important because non-compliance with treatment can increase the demand for healthcare services, further straining Peru’s already fragile health system.

In summary, we recommend the development and implementation of comprehensive, community-based interventions that integrate health education, social support, and improvements in healthcare accessibility—particularly for older adults with limited education, low income, and insufficient family or institutional support. These efforts will be crucial to reducing non-adherence and mitigating the burden of hypertension in Peru’s most vulnerable populations.

Conclusion

This study highlights key socioeconomic factors linked to non-adherence to antihypertensive treatment among older adults enrolled in the “Pension 65” program in Peru. The findings indicate that being male, single, having an incomplete primary education, and being enrolled in the SIS are associated with a higher likelihood of non-adherence to treatment. Additionally, individuals who had never held formal employment, those with an income of less than 450 soles (approximately 120 dollars), and those who did not receive any form of financial support were more likely to discontinue their treatment. These findings underscore the structural and personal barriers faced by older adults in vulnerable situations, emphasizing the need to improve health education and enhance access to medical services for this population.