Ageing is often associated with chronic illnesses, many of which require routine medication to enhance the quality of life for geriatric patients (1). Over 90% of individuals aged 60 and above live with at least one chronic illness, making regular medication use common among this population (2, 3). Medication adherence is a cornerstone for improving health outcomes in this population (4). However, the high burden of chronic medication use makes adherence to prescribed medications challenging (5). It is estimated that only 50% of geriatric patients worldwide adhere to prescribed medications (6). Similarly, in many African countries, less than 50% adhere to prescribed medications (7, 8). In Uganda, there is limited research on medication adherence among older persons; however, existing studies suggest that increasing age is associated with poorer adherence (9, 10). Additionally, many older persons frequently miss scheduled follow-up appointments, a factor known to contribute to non-adherence (11). Age-related factors, including cognitive impairment, impaired vision, and multiple comorbidities, further hinder medication adherence (12).

Limited access to healthcare services in many parts of Africa, particularly among geriatric patients, restricts access to medications and standard guidance (13). This stems from personal challenges in reaching healthcare facilities, limited availability of medications, the geographical location of health facilities, long waiting times, high patient-to-healthcare worker ratios, and stigma associated with old age, all of which can hinder medication adherence among geriatric patients (5, 14, 15) .

Many geriatric patients, who often have multiple comorbidities, have specific needs when accessing healthcare services (16). However, most PHC health facilities were originally designed to serve young populations, emphasizing curative care, which does not align with the needs of older patients (17). Similarly, several African countries report facing the same challenge, with PHC facilities often ill-equipped to meet the needs of geriatric patients (13). Although the World Health Organization (WHO) has advocated for age-friendly services to enhance healthcare accessibility for geriatric patients (18), in Uganda, where healthcare services are still inadequate and inaccessible for many, the situation is likely even more critical for this patient group (19).

Uganda’s PHC system is decentralized, with lower-level facilities, including health centers II, III, and IV, providing the services at the subnational level, and a referral network to the central level facilities (20, 21). In Uganda, many geriatric patients rely on PHC facilities for routine healthcare services. The system has been reported to have several limitations for service provision; however, data is limited on how it influences medication adherence among older persons (20, 21). This study set out to examine how access to healthcare services in PHC facilities affects medication adherence among patients aged 60 and above living with either diabetes, hypertension, or both. The findings will be crucial in informing interventions and policies geared towards enhancing healthcare access for the geriatric population.

Data collection: From December 2024 to February 2025, the study recruited geriatric patients aged 60 years and above at the outpatient departments of the study sites during designated diabetes and hypertension clinic days. Recruitment began at 8:00 AM, with participants identified in collaboration with facility healthcare workers. A pre-tested, researcher-administered questionnaire, available in English and Luganda – the local language of the study area – was used to collect data through individual interviews on adherence to medication and PHC accessibility factors influencing adherence to the prescribed medication among the participants (See supplementary file 1 for the detailed questionnaire). The questionnaire was designed by the study team by incorporating indicators from the PHC quality assessment tool (25) and the WHO PHC framework (26) and adapting questions to local contexts. Before full-scale data collection, the questionnaire was pretested with 15 participants aged 60 and above at a healthcare facility to assess clarity, relevance, and feasibility. Based on feedback from the pretest, necessary modifications were made to improve the instrument.

To evaluate its reliability, Cronbach’s alpha was calculated. The sample size for this analysis was determined using the method described by Bujang et al. (27), setting the null hypothesis Cronbach’s alpha (CA₀) at 0.0 and the alternative hypothesis (CA₁) at 0.6. With 40 study variables, a minimum sample size of 19 was required. The final reliability analysis yielded a Cronbach’s alpha of 0.81, indicating strong internal consistency when compared with the PHC quality assessment tool.

To assess medication adherence, the participants were asked how many tablets they had been able to take since the previous facility visit. The percentage of tablets taken compared to the tablets the patient received was recorded as adherence. A patient was considered to have adhered to medication if they took at least 80% of the medication. To assess factors influencing adherence, the researchers interviewed patients as guided by the indicators in the questionnaire, with clinical data verified from medical records

All data collection tools were checked for completeness before leaving the field.

Bivariate analysis was conducted to assess factors influencing adherence to prescribed medications among older persons with diabetes and hypertension. As shown in Table 3, the social demographic characteristics of the respondents that were significantly associated with adherence to prescribed medications among older persons with diabetes and hypertension included; age (χ2 = 14.38, p = < 0.001), sex (χ2 = 15.16, p = < 0.001), marital status (χ2 = 27.23, p = < 0.001), nature of residence (χ2 = 11.50, p = 0.003), highest education level (χ2 = 19.93, p = 0.001) and patient’s disease (χ2 = 8.19, p = 0.017). However, occupation and religion weren’t significantly associated with adherence to prescribed medications among older persons with diabetes and hypertension. Furthermore, in Table 4, findings showed that inaccessibility to healthcare facilities reduced adherence to medications; however, the association was not significant. Additionally, the findings show that adherence to prescribed medication was significantly reduced by; failure to get medications due stock outs (χ² = 64.24, p = 0.001), the lengthy waiting time at the facility that some time it made one leave the medicines and ended up missing taking medicine (χ² = 38.40, p = 0.001), and the lengthy time differences between review dates (χ² = 44.42, p = < 0.001).

In our study, we defined adherence as taking at least 80% of the prescribed medication, a threshold widely used in adherence studies as the minimum level for effective treatment (28, 29). Our findings show that only 23% of geriatric patients adhered to their medication, aligning closely with a review reporting 20–30% adherence among older persons with hypertension in selected European countries (1). Consistent with our findings, that study noted poor adherence among patients newly initiated on medication or older patients, making the low adherence in geriatric patients as they age, unsurprising. Our reported adherence prevalence is slightly below the pooled prevalence for Africa of 37.5%(8), possibly due to Uganda’s specific challenges, such as a poor supply chain limiting access to medicines compared to other countries (30).

Our results showed that various demographic factors significantly influenced adherence to medication. Our findings showed that as patients become older, their adherence to medication reduces, a similar finding in other studies. This can be attributed to age-related conditions that could minimize adherence, including reduced cognitive ability that comes with forgetfulness, poor vision and hearing, among others (12, 31). The findings further showed that the females were more adherent than males, similar to what many other studies have reported (14, 32). In many studies, females have been shown to have better health-seeking behavior than males. (33, 34). For this reason, it is no surprise that women take their medication better as prescribed compared to men. Our results also showed that participants with partners were more adherent to medications, which is not different from other studies (11, 35). Partners play a key role in caring for each other and thus improving the medication adherence of their family members (36). In one study, a diabetic patient was quoted, “I don’t think I’d be alive truly if it weren’t for my husband. The wonderful part about that is it’s great to have that support when you don’t feel good” (37). The lower adherence among the people who stayed in rural areas is a similar finding in related studies in Africa and elsewhere (38–40). These studies have listed some factors behind the low adherence, including patient delays in accessing their respective healthcare facilities, the poor accessibility to healthcare facilities and the poor economic status.

Our findings also showed that the higher the formal education, the higher the adherence, which is similar to other studies, in which adherence levels were found to be directly proportional to education levels (31, 32). This is expected since education increases patients’ knowledge about the medicines, which improves medication adherence (32). Studies in Uganda and elsewhere have shown that patients with a good understanding of their diseases and medication, and patients with high literacy levels, adhere to medication better than their counterparts (9, 41). Contrary to other studies, our findings show that participants with multiple illnesses were more adherent than those with one illness (1, 42). However, this may be because individuals with multiple chronic conditions may be highly motivated to manage their health because of the fear of being held down by one of the illnesses, hence demonstrating good adherence. Delays in taking diabetic and hypertensive medications instantly make the patients feel unwell, and thus, they are pushed to take their medication. In an attempt to take medications for one of the diseases, the patients are also compelled to take medication for the other disease.

Our findings indicate that many patients in Uganda miss medications due to drug stock-outs in government healthcare facilities. This challenge is corroborated by other researchers documenting frequent stock-outs in the country compared to many African countries, reporting that over 84% of Uganda’s healthcare facilities report stockouts of essential medicines in a year (30). In cases where health supply chain systems are lacking, and patients fail to access medicines as planned, with poor refill tendencies, there is reduced medication adherence (11, 43). Consequently, it is unsurprising that Uganda’s medication adherence prevalence is lower than the pooled African average and that reported in other studies (4, 7–9, 44). This may be because we examined adherence to medications for both hypertension and diabetes, whereas most studies focused on adherence to medication for a single condition.

Our findings show that accessibility to PHC facilities in Central Uganda remains a challenge for geriatric patients with chronic illness, negatively impacting medication adherence due to missed appointments. Participants highlighted issues such as long waiting times at facilities, limited medication availability, and transportation difficulties, particularly for older patients and rural residents. Other studies highlight similar gaps in Uganda’s PHC delivery for non-communicable disease management (45, 46). In our study, patients reported that the long intervals between review dates reduced their medication adherence, suggesting that a one-month interval would be more appropriate. In Uganda, many healthcare facilities schedule longer review periods to manage high patient loads due to the elevated patient-to-healthcare worker ratio (47, 48). Such elevated ratios also explain the long waiting hours at the facilities. Health care workers who actively plan and communicate medication schedules, enhance patient follow-up, and shorten intervals between hospital visits were found to improve adherence (11, 31, 35). However, some studies indicate that rigid routines may bore patients, potentially resulting in poor adherence. This underscores the importance of fostering strong healthcare worker-patient relationships to facilitate communication and identify optimal strategies for improving adherence (35).

Medication adherence was low among geriatric patients with hypertension, diabetes, or both, with only 23% taking at least 80% of their prescribed medication. Contributing factors included drug stock-outs, long waiting times at healthcare facilities, and extended intervals between review dates. Targeted strategies to improve drug availability are critical for enhancing adherence.