Perspectives of older people with uncontrolled type 2 diabetes mellitus towards medication adherence: A qualitative study

Background

Better medication adherence among people with diabetes mellitus was found to be associated with improved glycaemic control. However, medication non-adherence is a significant concern in older people with uncontrolled type 2 diabetes mellitus.

Purpose

To explore the perspectives of older people with uncontrolled type 2 diabetes mellitus towards medication adherence.

Design

A qualitative descriptive exploratory study.

Methodology

A purposive sample of older people with uncontrolled type 2 diabetes mellitus living in the community was recruited. Snowball sampling was applied in community recruitment. In‐depth telephone interviews were conducted using a semi‐structured interview guide. Interviews were transcribed verbatim. Thematic analysis was used in data analysis. The consolidated criteria for reporting qualitative research (COREQ) guidelines were followed.

Results

The emerged six themes were: (a) impact of knowledge, attitudes and practices on medication adherence, (b) treatment-related barriers to medication adherence, (c) impact of age-related changes on medication adherence, (d) person-related barriers to medication adherence, (e) impact of COVID-19 on medication adherence and, (f) role of support systems in medication adherence. Knowledge of the disease process and medications, attitudes towards medication adherence, the practice of different treatment approaches, self-medication and dosing, negative experiences related to medications, polypharmacy, changes in lifestyle and roles, the influence of work-life, motivation, negligence, family support, support received from health workers, facilities available and financial capability are the main factors influence medication adherence. Age-related memory impairment, visual disturbances and physical weaknesses affect medication adherence in older people. Additionally, COVID-19-related guidelines imposed by the government and healthcare system-related issues during the COVID-19 pandemic also affected medication adherence.

Conclusion

Adherence to medications among older people is hampered by a variety of factors, including their knowledge, attitudes and practices, person and treatment-related factors and age-related changes. The COVID-19 pandemic has brought additional challenges. Individualised patient care for older people with uncontrolled type 2 diabetes mellitus to improve medication adherence is timely. Strengthening support mechanisms for the above population is essential.

Study design, setting and participants

A qualitative descriptive exploratory study was undertaken. A purposive sample of 14 older people with uncontrolled T2DM participated in this study. Six participants who followed the Diabetic Clinic, Teaching Hospital, Peradeniya, Sri Lanka and eight patients from the community were recruited. In community recruitment, the snowball sampling method was used. In this study, participants aged 60 years and over who were diagnosed with DM by a physician with uncontrolled T2DM were included. Uncontrolled T2DM was determined by FBS value 129.6 mg/dl above or HbA1c value 7.2 mmol/L above [17, 20]. This study was conducted during the travel restrictions imposed by the government due to the COVID-19 pandemic; therefore, telephone interviews were conducted. Consequently, screening the participants with blood tests was not possible, and we recruited participants based on the values of FBS or HbA1c reported based on their recent blood reports. However, the majority of the participants were not aware of their HbA1c values. Therefore, participants who reported an FBS level of 130 mg/dl or above were considered as uncontrolled T2DM in this study. Additionally, patients who self-reported non-adherence to medicines and those who expressed willingness to articulate their experiences were included. Patients who had T1DM, hearing impairment, difficulty in communicating, and were disoriented to time, place and people were excluded. Participants were recruited until data saturation was reached. When the same information appears repeatedly in interviews, data saturation is achieved [21]. After completing 12 interviews, the authors found that there was no new information coming. Two additional interviews were conducted to check the data saturation. The data collection was completed with 14 interviews as no new codes were obtained with two additional interviews.

Data collection

A semi-structured interview guide (S1 Appendix) designed by researchers based on the research objectives and available literature was used. A holistic conceptual framework model to describe medication adherence guided the questions of the interview guide [22].

The interview guide consisted of nine open-ended questions and was reviewed by two experts in pharmacy and nursing who had experiences in qualitative research and medication management. The interview guide was pre-tested among three older people from the general population for its face validity, including the readability and understandability of the items. Socio-demographics of participants, including age, sex, ethnicity, religion, marital status, level of education and working status, were collected before interviews.

The approval for the data collection, particularly the extraction of contact numbers of the potential participants, was obtained from the Director, Teaching Hospital, Peradeniya, Sri Lanka. Participants were recruited from the Diabetic Clinic of the Teaching Hospital, Peradeniya, Sri Lanka and the community during May 2021 to June 2021. The participants from the hospital clinic were recruited through telephone contact while the snowball sampling method was followed in community recruitment. Participants were interviewed over the telephone at their convenience time when they were at home. This study was conducted during the COVID-19 pandemic; therefore, this method was the most practical. The average duration for interviews was 33 minutes, ranging from 20–45 minutes. Informed verbal consent was obtained from each participant before data collection. All interviews were digitally recorded, including verbal consent, with prior permission from the participants. While conducting interviews, only the interviewer (SU) and the participant were present. Reflective notes were maintained after each interview.

Data analysis

The digitally recorded files of the interviews were transcribed verbatim by the first researcher. The accuracy was checked by comparing it with the original recorded files. Demographic data were analysed using SPSS software (version 21). Inductive thematic analysis based on Braun and Clarke’s method [23] was used for qualitative data analysis. Two researchers coded the first three transcripts independently by active reading and re-reading of the transcripts. Consensus for the codes was achieved among the two researchers. Based on the coding of the three transcripts, an initial codebook was developed. The first researcher continued coding for the whole data set. The new codes that emerged were discussed with the second researcher to achieve consensus. Data were grouped into categories, themes and sub‐themes by the two researchers. Themes were reviewed, and definitions for each theme were built up. Naming for each theme was completed at the end of the data analysis. The findings were reported, and the consolidated criteria for reporting qualitative research (COREQ) checklist [24] was followed (S2 Appendix). In reporting, two researchers translated relevant quotes from Sinhala into the English language and consensus was achieved.

Ethical considerations

The ethical clearance for this study was obtained from the Ethics Review Committee, Faculty of Allied Health Sciences, University of Peradeniya, Sri Lanka (No: AHS/ERC/2021/009). The Director, Teaching Hospital, Peradeniya granted permission to recruit participants from the Diabetic Clinic, mainly collecting contact details of the potential participants. Informed verbal consent was obtained from each participant, and the consent was audio recorded as a part of the interviews. In this study, any personal data were not collected (i.e., names). However, any personal identities in verbatim were removed following transcription and before data analysis.

Trustworthiness of the study

The trustworthiness of the study was assured by several means, such as transferability, dependability and confirmability [25]. Transferability was confirmed by providing sufficient informative data on the setting, sample and sampling strategy, demographics, and semi-structured interviews. To assure dependability, the thematic analysis followed by Braun and Clarke’s method [23], the accepted standards of data analysis, was used. Confirmability was strengthened by developing a codebook based on the first three transcripts after achieving consensus among the two researchers for codes. The consensus was achieved for the newly formed codes in the transcription of other interviews. Consensus meetings were also held in the generation of themes and sub-themes.

Participant characteristics

In this study, 14 older people with uncontrolled T2DM were interviewed, including eight males and six females (Table 1). The average duration of the interviews was 33 minutes, ranging from 20 minutes to 45 minutes.

Findings

Six key themes emerged from the interviews, including a theme related to the impact of COVID-19 on medication adherence, as this study was conducted during the COVID-19 outbreak (Table 2). In the following section, these six main themes with accompanying sub-themes are described with sample quotes. Participants were made anonymous using a participant number (e.g.: P1) in the reporting.

Impact of knowledge, attitudes and practices on medication adherence

This study reports that older people have inadequate knowledge of medicines which leads to poor medication adherence, confirming the previous study findings with the general population [27, 28]. In this study, many patients do not know or cannot recognise their medications’ names. Conversely, a study conducted in Malaysia reports that all patients know the names and doses of the medicines they use [29]. In the present study, people who know the names are also unaware of the doses or strengths of medications. Patients have also identified their medicines according to their external features. If the manufacturers change the external feature or the government decides to purchase medicines from a different manufacturer, there is a risk of taking medication incorrectly. Consequently, improving knowledge of medicines is essential to improve the safe use of medicines among older people with DM. Therefore, health professionals, particularly doctors, nurses and pharmacists, need to pay special attention to delivering adequate knowledge for the patients.

This study reports that patients’ attitudes toward the use of medicines are related to medication adherence among older people with DM. Some participants held that they were aged; therefore, they felt that they did not want to take medicines. Therefore, cognitive behavioural interventions [30] are essential to make awareness of the worth of life. Similar to the findings of a previous study [31], societal influence affects medication adherence; if acquaintances tell patients to follow complementary and alternative medicines (CAM) rather than taking Western medicine or trying to control the disease by diet alone, patients have motivated to follow them. The literature supports that sometimes views of society are more powerful [16] compared to the health professionals’ teaching. Additionally, some studies have reported that religious, spiritual or ritual beliefs drive medication adherence among people with DM [31]. When a wide range of attitudes and societal influences exists, patient-specific approaches must be initiated to improve the correct use of medications.

Similar to the previous studies [17, 27, 31], this study further reports that medication adherence is influenced by the use of various treatment methods, particularly CAMs while taking Western medicine. A majority of the participants are on at least one CAM; for example, they use herbal remedies and/or ayurvedic treatments. Although a previous study reports that some patients resort to CAMs due to the influence of acquaintances [31], the present study reports the voluntary use of CAMs. Moreover, this study reports that the participants prefer alternative treatments over Western medicine because they view traditional remedies are safe and efficient. These findings are consistent with previous studies [27, 31] while inconsistent with a recent study in Kuwait [28]. Interestingly, the present study reports that older people use CAMs, for example, herbal leaves to lower their FBS while taking Western medicine. This practice may lead to poor controlling the symptoms and the development of complications.

Moreover, this study reported self-medication and self-dose adjustment by older people with uncontrolled T2DM. These findings are consistent with previous studies [17, 29]. These problems lead to suboptimal or toxic effects of oral hypoglycaemic agents (OHAs). Consequently, health education on adherence to medications needs to be expanded. The development of strategies and research is recommended to record and monitor all types of medicines (i.e., Western, CAMs) used by the patients.

Treatment-related barriers to medication adherence

Participants’ lived experiences with the disease interfere with medication adherence [16], and this study reports that the need for long-term medications leads to developing negative attitudes toward medication adherence. Therefore, education and adequate counselling are needed for patients who developed negative experiences with using medication for an extended period. Moreover, this study reports that frequent dosing leads to non-adherence. Therefore, reducing dosing frequency for older people with uncontrolled T2DM [32] or using sustained-release tablets where possible is recommended [33]. Additionally, the experience of side effects of OHAs was an essential factor in medication adherence among the study sample. The most commonly reported side effects are nausea, anorexia and drowsiness. Literature supports that side effects of medicines are associated with medication non-adherence [16]. The present study further reports that some patients are unaware of the side effects of OHAs. Similar findings have been reported previously [29]. Healthcare workers need to monitor the side effects of medications and can provide adequate information to fill the above knowledge gap.

Polypharmacy is a common problem among people with multiple chronic health problems. People with DM usually take five or more medicines to optimise blood glucose levels, blood pressure, and lipid control and manage other diabetes-related complications and comorbidities [32]. Consistent with previous studies, this study confirms that polypharmacy is a barrier to medication adherence among older patients with DM [31, 34]. Besides the possibility of medication non-adherence, polypharmacy causes several negative consequences, such as adverse drug effects and interactions [35, 36]. The Law of Therapeutic Parsimony highlights the need for using the minimum number of drugs, drug combinations, or drug preparations as well as minimum doses and frequency to achieve pre-decided therapeutic outcomes [37]. Consequently, a multi-disciplinary approach to minimising the impact of polypharmacy in older people with DM is needed [35].

Impact of age-related changes on medication adherence

The normal ageing process is associated with a decline in cognitive functions [38], and literature supports that memory plays a distinct role in medication adherence [39]. This study reveals that age-related memory impairment attributes to medication non-adherence in older people with uncontrolled T2DM. Therefore, strengthening family support is essential and additional support systems should be initiated and strengthened to minimise the impact of memory impairment in medication non-adherence among older people with uncontrolled T2DM. Moreover, older people’s poor eyesight is a barrier in proper medication management [40]. The present study also supports this phenomenon; therefore, health professionals need to pay special attention to the visual problems of older people, especially when providing information and health education. Additionally, poor vision can be developed as a complication of DM; therefore, monitoring visual problems, arranging eye referrals [20] and helping them to select appropriate visual aids are essential.

Age-related functional disabilities and weaknesses of older people result in physical dependency. The present study reports that the physical dependence of older people hinders proper clinic follow-up and meeting with health professionals. Therefore, flexible clinic schedules and strengthening support systems, particularly family support, are needed for older people with DM who are presented with age-related physical weaknesses.

Person-related barriers to medication adherence

The present study reports that changes in lifestyle and roles affect medication adherence. As people transition to retirement, their lifestyles are likely to change dramatically, and literature supports that retirement is associated with reduced physical activity [41]. This study indicates that some retired older people report long sleeping times and lack of hunger, leading to medication non-adherence. Therefore, modifications of lifestyles and strategies to improve their activities in retirement life are essential. In line with a previous study [16], this study reports that housekeeping roles significantly reduced medication adherence among older people with uncontrolled T2DM. The patient-centred healthcare system needs to be shifted to family-centred approaches [42]. Although the study population was older people, some of them are still doing some jobs. Literature supports that medication adherence is challenging with working conditions [17, 31]. The present study confirms that patients struggle to take medications properly while working. This study further reports that distress towards asking for leaves from administrators and working away from homes negatively affected attending clinics and taking continuous medications. Therefore, proper education and counselling are essential for older people with uncontrolled DM who are currently working.

Additionally, this study reported that lack of motivation and negligence are associated with medication adherence. Negligence is accompanied by forgetfulness, staying outside the home and travelling. The impact of patients’ negligence on medication adherence has also been reported in previous studies [17, 27, 29, 43]. The literature further supports that forgetfulness is one of the main barriers to medication adherence among patients with DM [43–45]. Forgetfulness would be addressed through adherence strategy education, for example setting up alarms [44].

Impact of COVID-19 on medication adherence

This additional theme has emerged concerning the COVID-19 outbreak. The government has imposed various COVID-19-related guidelines, for example, quarantining, travel restrictions and lockdowns, to minimise the spread of COVID-19 [46]. These guidelines have created additional challenges, particularly medication management and adherence for older people with uncontrolled T2DM. A similar situation has been reported in a recent study [47]. Minimising human movement which is an essential strategy in preventing the spread of COVID-19 [46], has negative impacts on attending clinics and getting prescription refills [47]. Patients with chronic diseases like DM and older people are at high risk of having more detrimental effects and dying from COVID-19 [47, 48]. Hence, special attention should be given to the above groups to ensure proper medication adherence during the pandemics like COVID-19. Additionally, with limited or no public transport, patients had to hire taxis to attend clinics, and this was costly for patients. Therefore, additional financial support or alternative transport facilities need to be initiated during a pandemic like COVID-19 to support people with poor economic status.

This study reports that government clinic followers had to take some medications from outside pharmacies, but medicines were out-of-stock in private pharmacies. During the COVID-19 pandemic, many low-to-middle-income countries have found a considerable gap in drug importation, especially for chronic illnesses [47]. These findings raise the need for policies to ensure the continuous availability of essential medicines equally during a crisis. Additionally, this study reports that patient education, awareness and counselling programs are not functioning correctly as a result of the COVID-19 situation. Consequently, patients have received limited education that directly impacts their medication adherence. Therefore, alternative methods, such as teleconsultation approaches (e-mail, online chat and video) [49], can be used in health education.

Role of support systems in medication adherence

Supportive family environments were found to be helpful in medication adherence [1, 27, 29, 50]. The present study confirms that non-supportive family environments and family conflicts lead to medication non-adherence. Interactive and economical family support can improve medication adherence among people with DM [16]. Therefore, it is recommended to address older people and their family members to provide insights into the importance of family cooperation in medication adherence.

In the present study, doctors, nurses and pharmacists have been identified as the main healthcare providers who first contact patients and provide education and support. However, limited patient-care provider interaction and limited time availability are reported. Patient-provider communication is crucial in medication adherence in patients with DM [17]. Moreover, this study reports negative experiences related to clinics, for example, crowded clinics, taking a long time at clinics, and unavailability of medicines at clinics. Easy accessibility [51] and patient satisfaction [51] with healthcare facilities are pivotal in medication adherence. Consequently, developing institutional policies and guidelines is essential to ensure proper patient-provider interaction and system-related issues.

• 1.Habte BM, Kebede T, Fenta TG, Boon H, Habte B. Barriers and facilitators to adherence to anti-diabetic medications: Ethiopian patients ‘ perspectives. African J Prim Heal Care Fam Med. 2017;9(1):1–9. doi: 10.4102/phcfm.v9i1.1411 [DOI] [PMC free article] [PubMed] [Google Scholar]
• 2.Zheng Y, Ley SH, Hu FB. Global aetiology and epidemiology of type 2 diabetes mellitus and its complications. Nat Rev Endocrinol. 2018;14(2):88–98. doi: 10.1038/nrendo.2017.151 [DOI] [PubMed] [Google Scholar]
• 3.Saeedi P, Petersohn I, Salpea P, Malanda B, Karuranga S, Unwin N, et al. Global and regional diabetes prevalence estimates for 2019 and projections for 2030 and 2045: Results from the International Diabetes Federation Diabetes Atlas, 9th edition. Diabetes Res Clin Pract. 2019;157:107843. doi: 10.1016/j.diabres.2019.107843 [DOI] [PubMed] [Google Scholar]
• 4.Cho NH, Shaw JE, Karuranga S, Huang Y, da Rocha Fernandes JD, Ohlrogge AW, et al. IDF Diabetes Atlas: Global estimates of diabetes prevalence for 2017 and projections for 2045. Diabetes Res Clin Pract. 2018;138:271–81. doi: 10.1016/j.diabres.2018.02.023 [DOI] [PubMed] [Google Scholar]
• 5.Williams R, Karuranga S, Malanda B, Saeedi P, Basit A, Besançon S, et al. Global and regional estimates and projections of diabetes-related health expenditure: Results from the International Diabetes Federation Diabetes Atlas, 9th edition. Diabetes Res Clin Pract. 2020. Apr;162:108072. doi: 10.1016/j.diabres.2020.108072 [DOI] [PubMed] [Google Scholar]
• 6.Strain WD, Hope S V., Green A, Kar P, Valabhji J, Sinclair AJ. Type 2 diabetes mellitus in older people: a brief statement of key principles of modern day management including the assessment of frailty. A national collaborative stakeholder initiative. Diabet Med. 2018. Jul;35(7):838–45. doi: 10.1111/dme.13644 [DOI] [PubMed] [Google Scholar]
• 7.Dunning T, Colagiuri S, Pruthi S, SV M. International Diabetes Federation Managing older people with type 2 diabetes. 2013. 12–23 p. [Google Scholar]
• 8.Maduwage S. Sri Lankan ‘ silver-aged ‘ population. J Coll Community Physicians Sri Lanka. 2019;25(1):1–3. [Google Scholar]
• 9.Sri Lanka Department of Census and Statistics. Sri Lanka Demographic and Health Survey 2016. 2017.
• 10.Somasundaram NP, Wijeyaratne PCN, Silva PS De, Siribaddana PS, Illangasekera PU. Diabetes Mellitus: Glucose Control. Sri Lanka J Diabetes, Endocrinol Metab. 2013;3(1):45–57. [Google Scholar]
• 11.Asche C, LaFleur J, Conner C. A Review of Diabetes Treatment Adherence and the Association with Clinical and Economic Outcomes. Clin Ther. 2011;33(1):74–109. doi: 10.1016/j.clinthera.2011.01.019 [DOI] [PubMed] [Google Scholar]
• 12.World Health Organization. ADHERENCE TO LONG-TERM THERAPIES Evidence for action. World Health Organization. 2003. Jun. [Google Scholar]
• 13.Lin LK, Sun Y, Heng BH, Kwang Chew DE, Chong PN. Medication adherence and glycemic control among newly diagnosed diabetes patients. BMJ Open Diabetes Res Care. 2017;5(1):1–10. doi: 10.1136/bmjdrc-2017-000429 [DOI] [PMC free article] [PubMed] [Google Scholar]
• 14.Leung E, Wongrakpanich S, Munshi MN. Diabetes Management in the Elderly. Jell inger. 2009;31(3):616–23. [DOI] [PMC free article] [PubMed] [Google Scholar]
• 15.Yap AF, Thirumoorthy T, Kwan YH. Medication adherence in the elderly. J Clin Gerontol Geriatr. 2016. Jun;7(2):64–7. [DOI] [PubMed] [Google Scholar]
• 16.Rezaei M, Valiee S, Tahan M, Ebtekar F, Gheshlagh RG. Barriers of medication adherence in patients with type-2 diabetes: A pilot qualitative study. Diabetes, Metab Syndr Obes Targets Ther. 2019;12:589–99. doi: 10.2147/DMSO.S197159 [DOI] [PMC free article] [PubMed] [Google Scholar]
• 17.Jaam M, Hadi MA, Kheir N, Ibrahim MIM, Diab MI, Al-Abdulla SA, et al. A qualitative exploration of barriers to medication adherence among patients with uncontrolled diabetes in Qatar: Integrating perspectives of patients and health care providers. Patient Prefer Adherence. 2018;12:2205–16. doi: 10.2147/PPA.S174652 [DOI] [PMC free article] [PubMed] [Google Scholar]
• 18.Aminde LN, Tindong M, Ngwasiri CA, Aminde JA, Njim T, Fondong AA, et al. Adherence to antidiabetic medication and factors associated with non-adherence among patients with type-2 diabetes mellitus in two regional hospitals in Cameroon. BMC Endocr Disord. 2019;19(1):1–9. [DOI] [PMC free article] [PubMed] [Google Scholar]
• 19.Gunathilake G, Kottahachchi D, Siyambalapitiya S. The drug compliance among patients with diabetes in Sri Lankan setting. Sri Lanka J Diabetes Endocrinol Metab. 2017;7(1):16. [Google Scholar]
• 20.American Diabetes Association. Standards of medical care in diabetes-2014. Diabetes Care. 2014. Jan 1;37(Supplement_1):S14–80. [DOI] [PubMed] [Google Scholar]
• 21.Saunders B, Sim J, Kingstone T, Baker S, Waterfield J, Bartlam B, et al. Saturation in qualitative research: exploring its conceptualization and operationalization. Qual Quant. 2018;52(4):1893–907. doi: 10.1007/s11135-017-0574-8 [DOI] [PMC free article] [PubMed] [Google Scholar]
• 22.Jaam M, Awaisu A, Mohamed Ibrahim MI, Kheir N. A holistic conceptual framework model to describe medication adherence in and guide interventions in diabetes mellitus. Res Soc Adm Pharm. 2018;14(4):391–7. doi: 10.1016/j.sapharm.2017.05.003 [DOI] [PubMed] [Google Scholar]
• 23.Braun V, Clarke V. Using thematic analysis in psychology. Qual Res Psychol. 2006;3(2):77–101. [Google Scholar]
• 24.Tong A, Sainsbury P, Craig J. Consolidated criteria for reporting qualitative research (COREQ): A 32-item checklist for interviews and focus groups. Int J Qual Heal Care. 2007;19(6):349–57. doi: 10.1093/intqhc/mzm042 [DOI] [PubMed] [Google Scholar]
• 25.Korstjens I, Moser A. Series: Practical guidance to qualitative research. Part 4: Trustworthiness and publishing. Eur J Gen Pract. 2018. Jan 1;24(1):120–4. doi: 10.1080/13814788.2017.1375092 [DOI] [PMC free article] [PubMed] [Google Scholar]
• 26.Chatterjee S, Davies MJ. Current management of diabetes mellitus and future directions in care. Postgrad Med J. 2015. Nov;91(1081):612–21. doi: 10.1136/postgradmedj-2014-133200 [DOI] [PubMed] [Google Scholar]
• 27.Dehdari L, Dehdari T. The determinants of anti-diabetic medication adherence based on the experiences of patients with type 2 diabetes. Arch Public Heal. 2019. Dec 16;77(1):21. doi: 10.1186/s13690-019-0347-z [DOI] [PMC free article] [PubMed] [Google Scholar]
• 28.Jeragh-Alhaddad F, Waheedi M, Barber N, Brock T. Barriers to medication taking among Kuwaiti patients with type 2 diabetes: a qualitative study. Patient Prefer Adherence. 2015. Oct;9:1491. doi: 10.2147/PPA.S86719 [DOI] [PMC free article] [PubMed] [Google Scholar]
• 29.Al-Qazaz HK, Hassali MA, Shafie AA, Syed Sulaiman SA, Sundram S. Perception and knowledge of patients with type 2 diabetes in Malaysia about their disease and medication: A qualitative study. Res Soc Adm Pharm. 2011. Jun;7(2):180–91. doi: 10.1016/j.sapharm.2010.04.005 [DOI] [PubMed] [Google Scholar]
• 30.Kini V, Ho PM. Interventions to Improve Medication Adherence: A Review. JAMA. 2018. Dec 18;320(23):2461–73. doi: 10.1001/jama.2018.19271 [DOI] [PubMed] [Google Scholar]
• 31.Atinga RA, Yarney L, Gavu NM. Factors influencing long-term medication non-adherence among diabetes and hypertensive patients in Ghana: A qualitative investigation. Barengo NC, editor. PLoS One. 2018. Mar 28;13(3):1–15. [DOI] [PMC free article] [PubMed] [Google Scholar]
• 32.Kocurek B. Promoting Medication Adherence in Older Adults … and the Rest of Us. Diabetes Spectr. 2009. Jan 1;22(2):80–4. [Google Scholar]
• 33.Derosa G, Angelo AD, Romano D, Maffioli P. Effects of metformin extended release compared to immediate release formula on glycemic control and glycemic variability in patients with type 2 diabetes. Dove Press J. 2017;11(1):1481–8. doi: 10.2147/DDDT.S131670 [DOI] [PMC free article] [PubMed] [Google Scholar]
• 34.Balkhi B, Alwhaibi M, Alqahtani N, Alhawassi T, Alshammari TM, Mahmoud M, et al. Oral antidiabetic medication adherence and glycaemic control among patients with type 2 diabetes mellitus: A cross-sectional retrospective study in a tertiary hospital in Saudi Arabia. BMJ Open. 2019;9(7):1–11. [DOI] [PMC free article] [PubMed] [Google Scholar]
• 35.Maher RL, Hanlon J, Hajjar ER. Clinical consequences of polypharmacy in elderly. Expert Opin Drug Saf. 2014. Jan 27;13(1):57–65. doi: 10.1517/14740338.2013.827660 [DOI] [PMC free article] [PubMed] [Google Scholar]
• 36.Mallet L, Spinewine A, Allen H. The challenge of managing drug interactions in elderly people. Lancet. 2007. Jan;370(July):185–91. doi: 10.1016/S0140-6736(07)61092-7 [DOI] [PubMed] [Google Scholar]
• 37.Kalra S, Gupta Y, Sahay R. The law of therapeutic parsimony. Indian J Endocrinol Metab. 2016;20(3):283. doi: 10.4103/2230-8210.180008 [DOI] [PMC free article] [PubMed] [Google Scholar]
• 38.Deary IJ, Corley J, Gow AJ, Harris SE, Houlihan LM, Marioni RE, et al. Age-associated cognitive decline. Br Med Bull. 2009. Dec 1;92(1):135–52. doi: 10.1093/bmb/ldp033 [DOI] [PubMed] [Google Scholar]
• 39.Zogg JB, Woods SP, Sauceda JA, Wiebe JS, Simoni JM. Review of an Emerging Literature. Behav Med J. 2012;35(1):47–62. [DOI] [PMC free article] [PubMed] [Google Scholar]
• 40.Griffiths R, Johnson M, Piper M. A nursing intervention for the quality use of medicines by elderly community clients. Int J Nurs Pract. 2004;10:166–76. doi: 10.1111/j.1440-172X.2004.00476.x [DOI] [PubMed] [Google Scholar]
• 41.Slingerland AS, Van Lenthe FJ, Jukema JW, Kamphuis CBM, Looman C, Giskes K, et al. Aging, retirement, and changes in physical activity: Prospective cohort findings from the GLOBE study. Am J Epidemiol. 2007;165(12):1356–63. doi: 10.1093/aje/kwm053 [DOI] [PubMed] [Google Scholar]
• 42.Trivedi R, Asch SM. Can We Improve Patient Adherence by Harnessing Social Forces? J Gen Intern Med. 2019. Jun 18;34(6):785–6. doi: 10.1007/s11606-019-04856-4 [DOI] [PMC free article] [PubMed] [Google Scholar]
• 43.Jaam M, Mohamed Ibrahim MI, Kheir N, Hadi MA, Diab MI, Awaisu A. Assessing prevalence of and barriers to medication adherence in patients with uncontrolled diabetes attending primary healthcare clinics in Qatar. Prim Care Diabetes. 2018;12(2):116–25. doi: 10.1016/j.pcd.2017.11.001 [DOI] [PubMed] [Google Scholar]
• 44.Wabe N, Angamo M, Hussein S. Medication adherence in diabetes mellitus and self management practices among type-2 diabetics in Ethiopia. N Am J Med Sci. 2011;3(9):418–23. doi: 10.4297/najms.2011.3418 [DOI] [PMC free article] [PubMed] [Google Scholar]
• 45.Ponnusankar S, Surulivelrajan M, Anandamoorthy N, Suresh B. Assessment of impact of medication counseling on patients’ medication knowledge and compliance in an outpatient clinic in South India. Patient Educ Couns. 2004. Jul;54(1):55–60. doi: 10.1016/S0738-3991(03)00193-9 [DOI] [PubMed] [Google Scholar]
• 46.Erandi KKWH, Mahasinghe AC, Perera SSN, Jayasinghe S. Effectiveness of the Strategies Implemented in Sri Lanka for Controlling the COVID-19 Outbreak. J Appl Math. 2020;1(1):1–10. [Google Scholar]
• 47.Kretchy IA, Asiedu-Danso M, Kretchy J paul. Medication management and adherence during the COVID-19 pandemic: Perspectives and experiences from low-and middle-income countries. Res Soc Adm Pharm. 2021. Jan;17(1):2023–6. doi: 10.1016/j.sapharm.2020.04.007 [DOI] [PMC free article] [PubMed] [Google Scholar]
• 48.Ho FK, Petermann-Rocha F, Gray SR, Jani BD, Katikireddi SV, Niedzwiedz CL, et al. Is older age associated with COVID-19 mortality in the absence of other risk factors? General population cohort study of 470,034 participants. Feng YM, editor. PLoS One. 2020. Nov 5;15(11). doi: 10.1371/journal.pone.0241824 [DOI] [PMC free article] [PubMed] [Google Scholar]
• 49.Ágh T, van Boven JF, Wettermark B, Menditto E, Pinnock H, Tsiligianni I, et al. A Cross-Sectional Survey on Medication Management Practices for Noncommunicable Diseases in Europe During the Second Wave of the COVID-19 Pandemic. Front Pharmacol. 2021. Jun 7;12(June):1–10. doi: 10.3389/fphar.2021.685696 [DOI] [PMC free article] [PubMed] [Google Scholar]
• 50.Baghikar S, Benitez A, Fernandez P, Yue P, Arshiya G. Factors Impacting Adherence to Diabetes Medication Among Urban, Low Income Mexican-Americans with Diabetes. J Immigr Minor Heal. 2019;21(6):1334–41. doi: 10.1007/s10903-019-00867-9 [DOI] [PMC free article] [PubMed] [Google Scholar]
• 51.Jin J, Sklar GE, Min V, Oh VM Sen, Li SC. Factors affecting therapeutic compliance: A review from the patient ‘ s perspective. Ther Clin Risk Manag. 2008;4(1):269–86. doi: 10.2147/tcrm.s1458 [DOI] [PMC free article] [PubMed] [Google Scholar]
• 52.Moon SJ, Lee WY, Hwang JS, Hong YP, Morisky DE. Accuracy of a screening tool for medication adherence: A systematic review and meta-analysis of the Morisky Medication Adherence Scale-8. Reboldi G, editor. PLoS One. 2017. Nov 2;12(11):1–18. doi: 10.1371/journal.pone.0187139 [DOI] [PMC free article] [PubMed] [Google Scholar]

Supplementary Materials

Data Availability Statement

The data underlying the results presented in the study are available from the DOI: 10.17605/OSF.IO/ERV23.