Evidence map›Paper›PMID 41559978›Full record

Observational studyMedicine2026

Comparative effectiveness of immediate-release and extended-release metformin on gastrointestinal tolerability, quality of life, and treatment satisfaction: A prospective cohort study.

Hisham Alshadfan, Hyder Mirghani, Tariq Alrasheed, Mansuor Alanazi, Amirah Alatawi, Mahmoud Elodemi, Muhammad Nazrul Hakim Abdullah

Abstract readComparative StudyObservational Study
In one paragraph

Observational study in Medicine, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors.

Hisham AlshadfanDepartment of Biomedical Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia.ORCID 0000-0002-6827-939
Hyder MirghaniDepartment of Internal Medicine, Faculty of Medicine, University of Tabuk, Tabuk, Saudi Arabia.ORCID 0000-0002-5817-6194
Tariq AlrasheedDepartment of Internal Medicine, Faculty of Medicine, University of Tabuk, Tabuk, Saudi Arabia.ORCID 0009-0009-8239-5061
Mansuor AlanaziDepartment of Family and Community Medicine, Faculty of Medicine, University of Tabuk, Tabuk, Saudi Arabia.ORCID 0000-0002-7256-6033
Amirah AlatawiDepartment of Family and Community Medicine, Faculty of Medicine, University of Tabuk, Tabuk, Saudi Arabia.ORCID 0000-0003-4638-9990
Mahmoud ElodemiDepartment of Pharmacology, Faculty of Medicine, University of Tabuk, Tabuk, Saudi Arabia.ORCID 0000-0002-5744-7773
Muhammad Nazrul Hakim AbdullahDepartment of Biomedical Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia.ORCID 0000-0002-4710-3467

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Gastrointestinal (GI) side effects from metformin often limit its use and can impact patient quality of life (QoL) and satisfaction. The extended-release (XR) formulation is thought to cause fewer GI adverse events than immediate-release (IR) metformin, potentially improving tolerability, treatment satisfaction, and adherence. To compare metformin IR vs XR in terms of GI tolerability (incidence of GI side effects), patient-reported QoL, and medication satisfaction over 6 months in Saudi patients with type 2 diabetes. In a prospective cohort of 119 newly diagnosed patients with type 2 diabetes (62 on IR, 57 on XR), we tracked GI adverse events using a standardized questionnaire at baseline and 6-month follow-up. Diabetes-specific QoL was measured with the diabetes therapy-related quality of life questionnaire (DTR-QOL), and treatment satisfaction was assessed with the oral hypoglycemic agent questionnaire version 2 (OHA-Q ver. 2). Metformin XR was associated with significantly better GI tolerability. By 6 months, 45.2% of IR patients and only 24.5% of XR patients reported any GI side effect (P <.05). Rates of bothersome symptoms, such as diarrhea, were notably higher in the IR group. Patients on XR reported fewer interruptions of therapy due to GI upset. The DTR-QOL global score improved in both groups (P <.05), but there was no significant difference in total DTR-QOL scores between groups (P = .390). The OHA-Q ver. 2 global score improved in both groups (P <.05), but the XR group had higher scores in domains related to satisfaction (median treatment satisfaction domain score 100 vs 77.78 for IR, P < .05), with a significant difference in OHA-Q ver. 2 global score (92.59 vs 86.31 for IR; P <.05). Metformin XR demonstrated superior GI tolerability, which translated into improved treatment satisfaction compared to IR. While the overall quality of life related to diabetes management improved similarly with both, the XR formulation reduced side effect burden, and the lower daily dosing led to higher patient-reported satisfaction. These findings support the use of metformin XR to enhance tolerability and adherence, potentially leading to improved long-term outcomes.

Indexed as

Diabetes Mellitus, Type 2Gastrointestinal DiseasesHypoglycemic AgentsMetforminPatient SatisfactionQuality of LifeAdultAgedDelayed-Action PreparationsFemaleHumansMaleMiddle AgedProspective StudiesSaudi ArabiaSurveys and QuestionnairesDelayed-Action PreparationsHypoglycemic AgentsMetformingastrointestinal side effectsmetformin extended-releasemetformin immediate-releasequality of lifetreatment satisfactiontype 2 diabetes

Identifiers

PMID41559978
PMCPMC12826287

What OpenQuestion holds

Texttitle and abstract
LicenceCC BY-NC
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.