1Division of Endocrinology and Metabolism, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea
2Department of Biostatistics, Korea University College of Medicine, Seoul, Korea
Copyright © 2021 Korean Diabetes Association
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
CONFLICTS OF INTEREST
No potential conflict of interest relevant to this article was reported.
AUTHOR CONTRIBUTIONS
Conception or design: N.H.K.
Acquisition, analysis, or interpretation of data: K.J.K., J.C., J.H.B., K.J.K., H.J.Y., J.A.S., N.H.K., K.M.C., S.H.B., S.G.K., N.H.K.
Drafting the work or revising: K.J.K.
Final approval of the manuscript: K.J.K., J.C., J.H.B., K.J.K., H.J.Y., J.A.S., N.H.K., K.M.C., S.H.B., S.G.K., N.H.K.
FUNDING
This study was supported by a Korea University Grant K1625581 (author Nam Hoon Kim).
Variable | Total (n=194) |
Time to reach target HbA1c (<7.0%) |
P value | |||
---|---|---|---|---|---|---|
<3 months (n=116) | 3–6 months (n=39) | ≥6 months (n=39) | ||||
Age, yr | 54.7±11.7 | 54.0±11.5 | 58.1±12.2 | 53.3±11.5 | 0.120 | |
Male sex | 119 (61.3) | 81 (69.8) | 17 (43.6) | 21 (53.8) | 0.021 | |
Weight, kg | 69.6±13.7 | 71.3±14.1 | 67.1±10.5 | 66.8±14.4 | 0.095 | |
Body mass index, kg/m2 | 25.6±4.0 | 25.9±4.3 | 25.4±2.8 | 24.9±3.8 | 0.352 | |
Waist circumference, cm | 87.6±12.5 | 88.1±14.2 | 88.7±8.5 | 85.2±10.2 | 0.404 | |
Smoking | 0.046 | |||||
None/Former/Current | 84 (43.3)/37 (19.1)/73 (37.6) | 44 (37.9)/21 (18.1)/51 (44.0) | 20 (51.3)/8 (20.5)/11 (28.2) | 20 (51.3)/8 (20.5)/11 (28.2) | ||
Alcohol | 0.217 | |||||
No/Yes | 96 (49.5)/98 (50.5) | 53 (45.7)/63 (54.3) | 24 (61.5)/15 (38.5) | 19 (48.7)/20 (51.3) | ||
Education | 0.029 | |||||
Less than middle school | 39 (20.1) | 18 (17.0) | 11 (34.4) | 10 (26.3) | ||
High school | 70 (36.1) | 41 (38.7) | 11 (34.4) | 18 (47.4) | ||
More than college | 67 (34.5) | 47 (44.3) | 10 (31.3) | 10 (26.3) | ||
Exercise | 0.962 | |||||
None | 115 (59.3) | 68 (59.6) | 23 (59.0) | 24 (61.5) | ||
≤2 times weekly | 13 (6.7) | 9 (7.9) | 1 (2.6) | 3 (7.7) | ||
≥3 times weekly | 64 (33.0) | 37 (32.5) | 15 (38.5) | 12 (30.8) | ||
Glucose, fasting, mg/dL | 166.9±64.6 | 161.39±63.6 | 165.6±65.8 | 185.3±64.6 | 0.147 | |
HbA1c at diagnosis, % | 9.1±2.3 | 8.9±2.3 | 8.9±2.3 | 9.7±2.3 | 0.149 | |
C-peptide, fasting, ng/mLa | 2.13±1.09 | 2.3±1.1 | 2.1±1.1 | 1.8±0.7 | 0.065 | |
Serum creatinine, mg/dL | 0.85±0.18 | 0.8±0.2 | 0.8±0.2 | 0.9±0.2 | 0.884 | |
Estimated GFR, mL/min/1.73 m2 | 88.3±20.6 | 90.2±19.5 | 86.0±18.2 | 85.0±25.3 | 0.291 | |
SBP, mm Hg | 127.0±15.9 | 125.8±14.2 | 127.5±16.2 | 130.1±20.1 | 0.348 | |
HDL-C, mg/dL | 46.0±10.9 | 45.7±9.7 | 47.7±13.1 | 45.3±12.2 | 0.553 | |
LDL-C, mg/dL | 96.1±32.6 | 94.1±36.0 | 97.3±25.1 | 101.1±28.1 | 0.601 | |
Triglyceride, mg/dL | 164.3±125.4 | 153.1±81.6 | 177.2±216.3 | 185.0±108.0 | 0.309 | |
Treatment | ||||||
Metformin | 157 (80.9) | 93 (80.2) | 33 (84.6) | 31 (79.5) | 0.523 | |
Sulfonylurea | 74 (38.1) | 37 (31.9) | 15 (38.5) | 22 (56.4) | 0.010 | |
Meglitinide | 11 (5.7) | 4 (3.4) | 2 (5.1) | 5 (12.8) | 0.050 | |
DPP-4 inhibitor | 33 (17.0) | 17 (14.7) | 8 (20.5) | 8 (20.5) | 0.343 | |
Thiazolidinedione | 19 (9.8) | 12 (10.3) | 3 (7.7) | 4 (10.3) | 0.516 | |
α-Glucosidase inhibitor | 3 (1.5) | 2 (1.7) | 0 | 1 (2.6) | 0.853 | |
Insulin | 48 (24.7) | 25 (21.6) | 8 (20.5) | 15 (38.5) | 0.063 | |
Statin | 98 (50.5) | 72 (85.7) | 28 (93.3) | 29 (93.5) | 0.385 | |
RAS inhibitor | 50 (25.8) | 23 (27.4) | 8 (26.7) | 10 (32.3) | 0.875 | |
Anti-thrombotics | 45 (23.2) | 27 (32.1) | 11 (36.7) | 8 (25.8) | 0.688 |
Values are presented as mean±standard deviation or number (%).
HbA1c, glycosylated hemoglobin; GFR, glomerular filtration rate; SBP, systolic blood pressure; HDL-C, high-density lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol; DPP-4, dipeptidyl peptidase-4; RAS, renin-angiotensin-aldosterone system.
a Statistical significance was estimated after log transformation.
Time to reach target HbA1c |
No. of events (%) |
Adjusted Hra |
|||||
---|---|---|---|---|---|---|---|
<3 months (n=116) | 3–6 months (n=39) | ≥6 months (n=39) | <3 months (n=116) | 3–6 months (n=39) | ≥6 months (n=39) | ||
Composite complications | 37 (31.9) | 12 (30.8) | 19 (48.7) | 0.47 (0.26–0.86) | 0.50 (0.23–1.10) | 1 (Reference) | |
Microvascular complications | 35 (30.2) | 12 (30.8) | 19 (48.7) | 0.42 (0.23–0.77) | 0.48 (0.22–1.05) | 1 (Reference) | |
Diabetic retinopathy | 23 (23.2) | 6 (16.2) | 10 (27.8) | 0.72 (0.27–1.90) | 0.56 (0.17–1.89) | 1 (Reference) | |
Diabetic neuropathy | 14 (14.4) | 8 (21.6) | 8 (22.2) | 0.60 (0.21–1.74) | 1.26 (0.37–4.30) | 1 (Reference) | |
Diabetic nephropathy | 16 (18.8) | 3 (10.0) | 8 (25.8) | 0.36 (0.12–1.10) | 0.23 (0.05–1.19) | 1 (Reference) | |
Macrovascular complications | 7 (6.0) | 3 (7.7) | 4 (10.3) | 0.37 (0.07–2.13) | 0.72 (0.11–4.62) | 1 (Reference) | |
Ischemic heart disease | 4 (4.8) | 2 (6.7) | 3 (9.4) | 0.35 (0.04–3.54) | 0.41 (0.03–5.24) | 1 (Reference) | |
Ischemic stroke | 2 (2.4) | 1 (3.3) | - | - | - | - | |
Peripheral artery disease | 1 (1.2) | 1 (3.3) | 1 (3.2) | 0.34 (0.01–9.79) | 1.31 (0.03–51.21) | 1 (Reference) |
HR, hazard ratio; HbA1c, glycosylated hemoglobin.
a Adjusted for age, sex, body mass index, smoking, alcohol, education, physical activity, mean low-density lipoprotein cholesterol, mean systolic blood pressure, baseline estimated glomerular filtration rate, glucose-lowering agents, antithrombotic agents, statins, antihypertensive drugs, and baseline HbA1c.
Item no. | Recommendation | Page no. | ||
---|---|---|---|---|
Title and abstract | 1 | (a) Indicate the study’s design with a commonly used term in the title or the abstract | 1–3 | |
(b) Provide in the abstract an informative and balanced summary of what was done and what was found | 2–3 | |||
Introduction | ||||
Background/rationale | 2 | Explain the scientific background and rationale for the investigation being reported | 4–5 | |
Objectives | 3 | State specific objectives, including any prespecified hypotheses | 5 | |
Methods | ||||
Study design | 4 | Present key elements of study design early in the paper | 5–6 | |
Setting | 5 | Describe the setting, locations, and relevant dates, including periods of recruitment, exposure, follow-up, and data collection | 5 | |
Participants | 6 | (a) Give the eligibility criteria, and the sources and methods of selection of participants. Describe methods of follow-up | 5–6 | |
(b) For matched studies, give matching criteria and number of exposed and unexposed | 5–6 | |||
Variables | 7 | Clearly define all outcomes, exposures, predictors, potential confounders, and effect modifiers. Give diagnostic criteria, if applicable | 7–8 | |
Data sources/measurement | 8a | For each variable of interest, give sources of data and details of methods of assessment (measurement). Describe comparability of assessment methods if there is more than one group | 6–7 | |
Bias | 9 | Describe any efforts to address potential sources of bias | 7–8 | |
Study size | 10 | Explain how the study size was arrived at | 8 | |
Quantitative variables | 11 | Explain how quantitative variables were handled in the analyses. If applicable, describe which groupings were chosen and why | 6–8 | |
Statistical methods | 12 | (a) Describe all statistical methods, including those used to control for confounding | 7–8 | |
(b) Describe any methods used to examine subgroups and interactions | 7–8 | |||
(c) Explain how missing data were addressed | 7–8 | |||
(d) If applicable, explain how loss to follow-up was addressed | 7–8 | |||
(e) Describe any sensitivity analyses | 7–8 | |||
Results | ||||
Participants | 13a | (a) Report numbers of individuals at each stage of study—e.g., numbers potentially eligible, examined for eligibility, confirmed eligible, included in the study, completing follow-up, and analysed | 8 (Supplementary Fig. 1) | |
(b) Give reasons for non-participation at each stage | 8 | |||
(c) Consider use of a flow diagram | 8 | |||
Descriptive data | 14a | (a) Give characteristics of study participants (e.g., demographic, clinical, social) and information on exposures and potential confounders | 8 (Table 1) | |
(b) Indicate number of participants with missing data for each variable of interest | 8 | |||
(c) Summarise follow-up time (e.g., average and total amount) | 6 | |||
Outcome data | 15a | Report numbers of outcome events or summary measures over time | 8–9 | |
Main results | 16 | (a) Give unadjusted estimates and, if applicable, confounder-adjusted estimates and their precision (e.g., 95% confidence interval). Make clear which confounders were adjusted for and why they were included | 8–9 | |
(b) Report category boundaries when continuous variables were categorized | 7 | |||
(c) If relevant, consider translating meaningful time period | 8–9 | |||
Other analyses | 17 | Report other analyses done—e.g., analyses of subgroups and interactions, and sensitivity analyses | 8–9 | |
Discussion | ||||
Key results | 18 | Summarise key results with reference to study objectives | 10 | |
Limitations | 19 | Discuss limitations of the study, taking into account sources of potential bias or imprecision. Discuss both direction and magnitude of any potential bias | 12–13 | |
Interpretation | 20 | Give a cautious overall interpretation of results considering objectives, limitations, multiplicity of analyses, results from similar studies, and other relevant evidence | 10–13 | |
Generalisability | 21 | Discuss the generalisability (external validity) of the study results | 11–12 | |
Other information | ||||
Funding | 22 | Give the source of funding and the role of the funders for the present study and, if applicable, for the original study on which the present article is based. | 13 |
An explanation and elaboration article discusses each checklist item and gives methodological background and published examples of transparent reporting. The STROBE checklist is best used in conjunction with this article (freely available on the Web sites of PLoS Medicine at http://www.plosmedicine.org/, Annals of Internal Medicine at http://www.annals.org/, and Epidemiology at http://www.epidem.com/). Information on the STROBE Initiative is available at http://www.strobe-statement.org.
a Give information separately for exposed and unexposed groups.
Variable | Total (n=194) | Time to reach target HbA1c (<7.0%) |
P value | |||
---|---|---|---|---|---|---|
<3 months (n=116) | 3–6 months (n=39) | ≥6 months (n=39) | ||||
Age, yr | 54.7±11.7 | 54.0±11.5 | 58.1±12.2 | 53.3±11.5 | 0.120 | |
Male sex | 119 (61.3) | 81 (69.8) | 17 (43.6) | 21 (53.8) | 0.021 | |
Weight, kg | 69.6±13.7 | 71.3±14.1 | 67.1±10.5 | 66.8±14.4 | 0.095 | |
Body mass index, kg/m2 | 25.6±4.0 | 25.9±4.3 | 25.4±2.8 | 24.9±3.8 | 0.352 | |
Waist circumference, cm | 87.6±12.5 | 88.1±14.2 | 88.7±8.5 | 85.2±10.2 | 0.404 | |
Smoking | 0.046 | |||||
None/Former/Current | 84 (43.3)/37 (19.1)/73 (37.6) | 44 (37.9)/21 (18.1)/51 (44.0) | 20 (51.3)/8 (20.5)/11 (28.2) | 20 (51.3)/8 (20.5)/11 (28.2) | ||
Alcohol | 0.217 | |||||
No/Yes | 96 (49.5)/98 (50.5) | 53 (45.7)/63 (54.3) | 24 (61.5)/15 (38.5) | 19 (48.7)/20 (51.3) | ||
Education | 0.029 | |||||
Less than middle school | 39 (20.1) | 18 (17.0) | 11 (34.4) | 10 (26.3) | ||
High school | 70 (36.1) | 41 (38.7) | 11 (34.4) | 18 (47.4) | ||
More than college | 67 (34.5) | 47 (44.3) | 10 (31.3) | 10 (26.3) | ||
Exercise | 0.962 | |||||
None | 115 (59.3) | 68 (59.6) | 23 (59.0) | 24 (61.5) | ||
≤2 times weekly | 13 (6.7) | 9 (7.9) | 1 (2.6) | 3 (7.7) | ||
≥3 times weekly | 64 (33.0) | 37 (32.5) | 15 (38.5) | 12 (30.8) | ||
Glucose, fasting, mg/dL | 166.9±64.6 | 161.39±63.6 | 165.6±65.8 | 185.3±64.6 | 0.147 | |
HbA1c at diagnosis, % | 9.1±2.3 | 8.9±2.3 | 8.9±2.3 | 9.7±2.3 | 0.149 | |
C-peptide, fasting, ng/mL |
2.13±1.09 | 2.3±1.1 | 2.1±1.1 | 1.8±0.7 | 0.065 | |
Serum creatinine, mg/dL | 0.85±0.18 | 0.8±0.2 | 0.8±0.2 | 0.9±0.2 | 0.884 | |
Estimated GFR, mL/min/1.73 m2 | 88.3±20.6 | 90.2±19.5 | 86.0±18.2 | 85.0±25.3 | 0.291 | |
SBP, mm Hg | 127.0±15.9 | 125.8±14.2 | 127.5±16.2 | 130.1±20.1 | 0.348 | |
HDL-C, mg/dL | 46.0±10.9 | 45.7±9.7 | 47.7±13.1 | 45.3±12.2 | 0.553 | |
LDL-C, mg/dL | 96.1±32.6 | 94.1±36.0 | 97.3±25.1 | 101.1±28.1 | 0.601 | |
Triglyceride, mg/dL | 164.3±125.4 | 153.1±81.6 | 177.2±216.3 | 185.0±108.0 | 0.309 | |
Treatment | ||||||
Metformin | 157 (80.9) | 93 (80.2) | 33 (84.6) | 31 (79.5) | 0.523 | |
Sulfonylurea | 74 (38.1) | 37 (31.9) | 15 (38.5) | 22 (56.4) | 0.010 | |
Meglitinide | 11 (5.7) | 4 (3.4) | 2 (5.1) | 5 (12.8) | 0.050 | |
DPP-4 inhibitor | 33 (17.0) | 17 (14.7) | 8 (20.5) | 8 (20.5) | 0.343 | |
Thiazolidinedione | 19 (9.8) | 12 (10.3) | 3 (7.7) | 4 (10.3) | 0.516 | |
α-Glucosidase inhibitor | 3 (1.5) | 2 (1.7) | 0 | 1 (2.6) | 0.853 | |
Insulin | 48 (24.7) | 25 (21.6) | 8 (20.5) | 15 (38.5) | 0.063 | |
Statin | 98 (50.5) | 72 (85.7) | 28 (93.3) | 29 (93.5) | 0.385 | |
RAS inhibitor | 50 (25.8) | 23 (27.4) | 8 (26.7) | 10 (32.3) | 0.875 | |
Anti-thrombotics | 45 (23.2) | 27 (32.1) | 11 (36.7) | 8 (25.8) | 0.688 |
Time to reach target HbA1c | No. of events (%) |
Adjusted Hr |
|||||
---|---|---|---|---|---|---|---|
<3 months (n=116) | 3–6 months (n=39) | ≥6 months (n=39) | <3 months (n=116) | 3–6 months (n=39) | ≥6 months (n=39) | ||
Composite complications | 37 (31.9) | 12 (30.8) | 19 (48.7) | 0.47 (0.26–0.86) | 0.50 (0.23–1.10) | 1 (Reference) | |
Microvascular complications | 35 (30.2) | 12 (30.8) | 19 (48.7) | 0.42 (0.23–0.77) | 0.48 (0.22–1.05) | 1 (Reference) | |
Diabetic retinopathy | 23 (23.2) | 6 (16.2) | 10 (27.8) | 0.72 (0.27–1.90) | 0.56 (0.17–1.89) | 1 (Reference) | |
Diabetic neuropathy | 14 (14.4) | 8 (21.6) | 8 (22.2) | 0.60 (0.21–1.74) | 1.26 (0.37–4.30) | 1 (Reference) | |
Diabetic nephropathy | 16 (18.8) | 3 (10.0) | 8 (25.8) | 0.36 (0.12–1.10) | 0.23 (0.05–1.19) | 1 (Reference) | |
Macrovascular complications | 7 (6.0) | 3 (7.7) | 4 (10.3) | 0.37 (0.07–2.13) | 0.72 (0.11–4.62) | 1 (Reference) | |
Ischemic heart disease | 4 (4.8) | 2 (6.7) | 3 (9.4) | 0.35 (0.04–3.54) | 0.41 (0.03–5.24) | 1 (Reference) | |
Ischemic stroke | 2 (2.4) | 1 (3.3) | - | - | - | - | |
Peripheral artery disease | 1 (1.2) | 1 (3.3) | 1 (3.2) | 0.34 (0.01–9.79) | 1.31 (0.03–51.21) | 1 (Reference) |
Item no. | Recommendation | Page no. | ||
---|---|---|---|---|
Title and abstract | 1 | (a) Indicate the study’s design with a commonly used term in the title or the abstract | 1–3 | |
(b) Provide in the abstract an informative and balanced summary of what was done and what was found | 2–3 | |||
Introduction | ||||
Background/rationale | 2 | Explain the scientific background and rationale for the investigation being reported | 4–5 | |
Objectives | 3 | State specific objectives, including any prespecified hypotheses | 5 | |
Methods | ||||
Study design | 4 | Present key elements of study design early in the paper | 5–6 | |
Setting | 5 | Describe the setting, locations, and relevant dates, including periods of recruitment, exposure, follow-up, and data collection | 5 | |
Participants | 6 | (a) Give the eligibility criteria, and the sources and methods of selection of participants. Describe methods of follow-up | 5–6 | |
(b) For matched studies, give matching criteria and number of exposed and unexposed | 5–6 | |||
Variables | 7 | Clearly define all outcomes, exposures, predictors, potential confounders, and effect modifiers. Give diagnostic criteria, if applicable | 7–8 | |
Data sources/measurement | 8 |
For each variable of interest, give sources of data and details of methods of assessment (measurement). Describe comparability of assessment methods if there is more than one group | 6–7 | |
Bias | 9 | Describe any efforts to address potential sources of bias | 7–8 | |
Study size | 10 | Explain how the study size was arrived at | 8 | |
Quantitative variables | 11 | Explain how quantitative variables were handled in the analyses. If applicable, describe which groupings were chosen and why | 6–8 | |
Statistical methods | 12 | (a) Describe all statistical methods, including those used to control for confounding | 7–8 | |
(b) Describe any methods used to examine subgroups and interactions | 7–8 | |||
(c) Explain how missing data were addressed | 7–8 | |||
(d) If applicable, explain how loss to follow-up was addressed | 7–8 | |||
(e) Describe any sensitivity analyses | 7–8 | |||
Results | ||||
Participants | 13 |
(a) Report numbers of individuals at each stage of study—e.g., numbers potentially eligible, examined for eligibility, confirmed eligible, included in the study, completing follow-up, and analysed | 8 ( |
|
(b) Give reasons for non-participation at each stage | 8 | |||
(c) Consider use of a flow diagram | 8 | |||
Descriptive data | 14 |
(a) Give characteristics of study participants (e.g., demographic, clinical, social) and information on exposures and potential confounders | 8 ( |
|
(b) Indicate number of participants with missing data for each variable of interest | 8 | |||
(c) Summarise follow-up time (e.g., average and total amount) | 6 | |||
Outcome data | 15 |
Report numbers of outcome events or summary measures over time | 8–9 | |
Main results | 16 | (a) Give unadjusted estimates and, if applicable, confounder-adjusted estimates and their precision (e.g., 95% confidence interval). Make clear which confounders were adjusted for and why they were included | 8–9 | |
(b) Report category boundaries when continuous variables were categorized | 7 | |||
(c) If relevant, consider translating meaningful time period | 8–9 | |||
Other analyses | 17 | Report other analyses done—e.g., analyses of subgroups and interactions, and sensitivity analyses | 8–9 | |
Discussion | ||||
Key results | 18 | Summarise key results with reference to study objectives | 10 | |
Limitations | 19 | Discuss limitations of the study, taking into account sources of potential bias or imprecision. Discuss both direction and magnitude of any potential bias | 12–13 | |
Interpretation | 20 | Give a cautious overall interpretation of results considering objectives, limitations, multiplicity of analyses, results from similar studies, and other relevant evidence | 10–13 | |
Generalisability | 21 | Discuss the generalisability (external validity) of the study results | 11–12 | |
Other information | ||||
Funding | 22 | Give the source of funding and the role of the funders for the present study and, if applicable, for the original study on which the present article is based. | 13 |
Values are presented as mean±standard deviation or number (%). HbA1c, glycosylated hemoglobin; GFR, glomerular filtration rate; SBP, systolic blood pressure; HDL-C, high-density lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol; DPP-4, dipeptidyl peptidase-4; RAS, renin-angiotensin-aldosterone system. Statistical significance was estimated after log transformation.
HR, hazard ratio; HbA1c, glycosylated hemoglobin. Adjusted for age, sex, body mass index, smoking, alcohol, education, physical activity, mean low-density lipoprotein cholesterol, mean systolic blood pressure, baseline estimated glomerular filtration rate, glucose-lowering agents, antithrombotic agents, statins, antihypertensive drugs, and baseline HbA1c.
An explanation and elaboration article discusses each checklist item and gives methodological background and published examples of transparent reporting. The STROBE checklist is best used in conjunction with this article (freely available on the Web sites of Give information separately for exposed and unexposed groups.