Home › Research › Caregiving
A systematic review of medication non-adherence in persons with dementia or cognitive impairment
Smith D, Lovell J, Weller C, Kennedy B, Winbolt M, Young C, Ibrahim J.. PloS one, 2017-02-06
Topic: Risk, prevention and care in population studies
Background Adherence to medication is vital for disease management while simultaneously reducing healthcare expenditure. Older persons with cognitive impairment (CI) are at risk for non-adherence as cognitive processes are needed to manage medications. This systematic review focuses on the relationship between medication non-adherence and specific cognitive domains in persons with CI, and explores determinants of medication non-adherence. When available, relationships and factors are compared with cognitively intact populations. Methods A seven database systematic search of studies published between 1 January 1949-31 December 2015 examining medication non-adherence in community dwelling persons with CI or dementia was conducted. Articles reporting medication non-adherence in people with CI or dementia in the community, with or without caregiver supports were eligible for inclusion. Papers reporting adherence to treatments in cognitively intact populations, populations from hospital or institutional settings, for non-prescribed medication or those describing dementia as a factor predicting medication non-adherence were excluded. Data on study and population characteristics, research design, data sources and analysis, specific cognitive domains, non-adherence prevalence, measurement of adherence, salient findings, factors associated with adherence and strategies to improve medication adherence were extracted. Study limitations included inconsistencies between data sources and definitions, resulting in a loss of fidelity in the value and comprehensiveness of data, as well as exclusion of non-pharmacological treatments and regimens. Findings Fifteen studies met inclusion criteria. Adherence among CI subjects ranged from 10.7%-38% with better rates of adherence in non-CI individuals. Medication non-adherence definitions varied considerably. New-learning, memory and executive functioning were associated with improved adherence and formed the focus of most studies. Multiple factors were identified as modulators of non-adherence. Conclusion This review highlights a gap in knowledge on how specific cognitive domains contribute to medication non-adherence amongst CI populations, and demonstrates the current focus is limited to two domains: memory and executive functioning.
Key findings
- When available, relationships and factors are compared with cognitively intact populations.
- Data on study and population characteristics, research design, data sources and analysis, specific cognitive domains, non-adherence prevalence, measurement of adherence, salient findings, factors associated with adherence and strategies to improve medication adherence were extracted.
- New-learning, memory and executive functioning were associated with improved adherence and formed the focus of most studies.
Why it matters
This systematic review of community-dwelling people with cognitive impairment or dementia found that new-learning, memory, and executive functioning were associated with improved medication adherence and were the focus of most studies. It extracted data on adherence factors and strategies to improve medication adherence, comparing them with cognitively intact populations when available.
New to this subject? Start with our plain-English guide: Caregiving →
Study details
- Study designsystematic review
- Effect size10.7%
- Evidence strengthHigh
How this study scored 67/100
Published in a peer-reviewed journal, and it is a systematic review of all the studies on the question. Scored zero for sample size and studied in people because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (PloS one) |
| Journal's citation record | 4 / 4 | PLoS ONE: journal h-index 594 (OpenAlex, 2026-10-29) |
| Study design | 12 / 12 | A systematic review of all the studies on the question |
| Strength of evidence | 5 / 5 | Rated “high” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 2 / 5 | 2017 — within 10 year(s) of the newest study here |
| Sample size | 0 / 4 | Participant count not stated — scores zero (not stated in the record — scored 0) |
| Effect reported | 2 / 3 | Effect reported as a number, without an interval or test |
| Studied in people | 0 / 3 | Not stated whether this was studied in people — scores zero (not stated in the record — scored 0) |
| Randomised / blinded | 0 / 2 | A review of other studies — randomisation is not credited here |
| Times cited | 5 / 7 | Cited 241 times (OpenAlex, 2026-10-10) |
| Citations per year | 4 / 5 | 21.9 citations a year over 11 year(s) since 2017 |
| Impact for its field and year | 3 / 6 | Cited 4.3× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 2 / 6 | Cited by 5 other studies in this library |
| Still being cited | 3 / 4 | Cited 85 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 2 / 4 | Last-listed author Joseph Ibrahim: h-index 34 (OpenAlex, whole career) |
| Institution's track record | 1 / 3 | Monash University: institution h-index 1,146 (OpenAlex) |
| Multi-centre collaboration | 1 / 3 | OpenAlex lists 3 institution(s) in 1 country |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 28166234) |
| Free to read | 2 / 2 | Free to read |
| Total | 67 / 100 | — |
What each of these 20 components measures, and what this score is not →
Read the original
Full text: free to read — OpenAlex lists this copy as free to read: the link above (checked 6 Feb 1020).
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. The record names 7 authors; APA and Vancouver show the first six, BibTeX and the downloads carry all of them. Check the citation against the original before you use it.
APA 7th
Smith, D., Lovell, J., Weller, C., Kennedy, B., Winbolt, M., Young, C., et al. (2017). A systematic review of medication non-adherence in persons with dementia or cognitive impairment. PloS one. https://doi.org/10.1371/journal.pone.0170651
Vancouver
Smith D, Lovell J, Weller C, Kennedy B, Winbolt M, Young C, et al. A systematic review of medication non-adherence in persons with dementia or cognitive impairment. PloS one. 2017. doi:10.1371/journal.pone.0170651. PMID: 28166234.
BibTeX
@article{smith2017-28166234,
author = {Smith, D. and Lovell, J. and Weller, C. and Kennedy, B. and Winbolt, M. and Young, C. and Ibrahim, J.},
title = {{A systematic review of medication non-adherence in persons with dementia or cognitive impairment}},
journal = {PloS one},
year = {2017},
doi = {10.1371/journal.pone.0170651},
pmid = {28166234},
url = {https://doi.org/10.1371/journal.pone.0170651}
}
Studies this one cites
Referenced by this study and also in the alzhub library, so you can read them here.
Later studies that cite this one
5 studies in the alzhub library list this one in their references.
Related studies in Caregiving
Also tagged “care”
996 studies in the library carry the topic tag “care”; these are this study's neighbours in a fixed, alphabetical-by-hash tour of them, not the closest in content. All 996 tagged studies.