1Department of Dental Hygiene, Silla University, Busan, Korea
2Department of Physiology, Dong-A University College of Medicine, Busan, Korea
3Institute of Health Medical Education Convergence Research, Kangwon National University, Samcheok, Korea
© 2025, Korean Society of Epidemiology
This is an open-access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Data availability
The data that support the findings of this study are available from the corresponding author upon reasonable request.
Conflict of interest
The authors have no conflicts of interest to declare for this study.
Funding
This work was supported by the Dong-A University research fund.
Acknowledgements
None.
Author contributions
Conceptualization: Son M, Kim SR, Kim YR. Data curation: Kim SR, Kim YR, Son M. Formal analysis: Son M. Funding acquisition: Son M. Methodology: Son M, Kim YR. Project administration: Son M, Kim SR, Kim YR. Visualization: Kim SR, Son M. Writing – original draft: Son M, Kim SR, Kim YR. Writing – review & editing: Kim YR, Kim SR, Son M.
Group | n | Events (n) | Follow-up duration (PY) | Incidence rate (per 1,000 PY) | Crude HR (95% CI) | p-value | Adjusted1 HR (95% CI) | p-value |
---|---|---|---|---|---|---|---|---|
Composite of outcomes | ||||||||
Infrequent group | 10,742 | 293 | 52,507 | 5.58 | 1.00 (reference) | 1.00 (reference) | ||
Occasional group | 9,495 | 111 | 46,517 | 2.39 | 0.43 (0.34, 0.53) | <0.001 | 0.60 (0.48, 0.76) | <0.001 |
Regular group | 5,521 | 38 | 27,258 | 1.39 | 0.25 (0.18, 0.35) | <0.001 | 0.40 (0.29, 0.57) | <0.001 |
Ischemic stroke | ||||||||
Infrequent group | 10,742 | 269 | 52,541 | 5.12 | 1.00 (reference) | 1.00 (reference) | ||
Occasional group | 9,495 | 105 | 46,525 | 2.26 | 0.44 (0.35, 0.55) | <0.001 | 0.63 (0.50, 0.79) | <0.001 |
Regular group | 5,521 | 36 | 27,262 | 1.32 | 0.26 (0.18, 0.36) | <0.001 | 0.43 (0.30, 0.61) | <0.001 |
Hemorrhagic stroke | ||||||||
Infrequent group | 10,742 | 28 | 53,098 | 0.53 | 1.00 (reference) | 1.00 (reference) | ||
Occasional group | 9,495 | 7 | 46,741 | 0.15 | 0.29 (0.13, 0.66) | 0.003 | 0.37 (0.16, 0.87) | 0.022 |
Regular group | 5,521 | 2 | 27,331 | 0.07 | 0.14 (0.03, 0.59) | 0.007 | 0.19 (0.04, 0.83) | 0.027 |
Group | n | Events (n) | Follow-up duration (PY) | Incidence rate (per 1,000 PY) | Crude HR (95% CI) | p-value | Adjusted1 HR (95% CI) | p-value |
---|---|---|---|---|---|---|---|---|
Landmark analysis (follow-up after 1yr) | ||||||||
Infrequent group | 10,575 | 238 | 52,411 | 4.54 | 1.00 (reference) | 1.00 (reference) | ||
Occasional group | 9,476 | 93 | 46,506 | 2.00 | 0.44 (0.35, 0.56) | <0.001 | 0.62 (0.49, 0.80) | <0.001 |
Regular group | 5,514 | 31 | 27,253 | 1.14 | 0.25 (0.17, 0.36) | <0.001 | 0.41 (0.28, 0.60) | <0.001 |
Landmark analysis (follow-up after 2 yr) | ||||||||
Infrequent group | 10,343 | 174 | 52,060 | 3.34 | 1.00 (reference) | 1.00 (reference) | ||
Occasional group | 9,447 | 77 | 46,460 | 1.66 | 0.50 (0.38, 0.66) | <0.001 | 0.73 (0.55, 0.96) | <0.001 |
Regular group | 5,510 | 27 | 27,245 | 0.99 | 0.30 (0.20, 0.45) | <0.001 | 0.50 (0.33, 0.76) | <0.001 |
Characteristics | Infrequent group (n=10,742) | Occasional group (n=9,495) | Regular group (n=5,521) | p-value |
---|---|---|---|---|
Sex | 0.580 | |||
Male | 5,577 (51.9) | 4,991 (52.6) | 2,904 (52.6) | |
Female | 5,165 (48.1) | 4,504 (47.4) | 2,617 (47.4) | |
Age (yr) | 65.4±9.5 | 61.8±7.6 | 60.6±6.8 | <0.001 |
Income level (quartile) | <0.001 | |||
1st | 1,857 (17.3) | 1,468 (15.5) | 782 (14.2) | |
2nd | 2,465 (22.9) | 1,998 (21.0) | 1,031 (18.7) | |
3rd | 3,268 (30.4) | 2,820 (29.7) | 1,484 (26.9) | |
4th | 3,152 (29.3) | 3,209 (33.8) | 2,224 (40.3) | |
Residence | <0.001 | |||
Rural | 4,950 (46.1) | 3,321 (35.0) | 1,436 (26.0) | |
Urban | 5,792 (53.9) | 6,174 (65.0) | 4,085 (74.0) | |
Hypertension | 5,823 (54.2) | 4,352 (45.8) | 2,399 (43.5) | <0.001 |
Diabetes | 1,909 (17.8) | 1,292 (13.6) | 651 (11.8) | <0.001 |
Dyslipidemia | 4,042 (37.6) | 3,502 (36.9) | 2,108 (38.2) | 0.260 |
Myocardial infarction | 383 (3.6) | 301 (3.2) | 151 (2.7) | 0.020 |
Depression | 2,730 (25.4) | 2,248 (23.7) | 1,295 (23.5) | 0.003 |
Charlson comorbidity index | <0.001 | |||
0 | 3,793 (35.3) | 3,711 (39.1) | 2,174 (39.4) | |
1 | 2,691 (25.1) | 2,506 (26.4) | 1,532 (27.7) | |
2 | 1,746 (16.3) | 1,540 (16.2) | 884 (16.0) | |
≥3 | 2,512 (23.4) | 1,738 (18.3) | 931 (16.9) | |
Ratio | 0.1±0.1 | 0.4±0.1 | 0.9±0.1 | <0.001 |
Group | n | Events (n) | Follow-up duration (PY) | Incidence rate (per 1,000 PY) | Crude HR (95% CI) | p-value | Adjusted |
p-value |
---|---|---|---|---|---|---|---|---|
Composite of outcomes | ||||||||
Infrequent group | 10,742 | 293 | 52,507 | 5.58 | 1.00 (reference) | 1.00 (reference) | ||
Occasional group | 9,495 | 111 | 46,517 | 2.39 | 0.43 (0.34, 0.53) | <0.001 | 0.60 (0.48, 0.76) | <0.001 |
Regular group | 5,521 | 38 | 27,258 | 1.39 | 0.25 (0.18, 0.35) | <0.001 | 0.40 (0.29, 0.57) | <0.001 |
Ischemic stroke | ||||||||
Infrequent group | 10,742 | 269 | 52,541 | 5.12 | 1.00 (reference) | 1.00 (reference) | ||
Occasional group | 9,495 | 105 | 46,525 | 2.26 | 0.44 (0.35, 0.55) | <0.001 | 0.63 (0.50, 0.79) | <0.001 |
Regular group | 5,521 | 36 | 27,262 | 1.32 | 0.26 (0.18, 0.36) | <0.001 | 0.43 (0.30, 0.61) | <0.001 |
Hemorrhagic stroke | ||||||||
Infrequent group | 10,742 | 28 | 53,098 | 0.53 | 1.00 (reference) | 1.00 (reference) | ||
Occasional group | 9,495 | 7 | 46,741 | 0.15 | 0.29 (0.13, 0.66) | 0.003 | 0.37 (0.16, 0.87) | 0.022 |
Regular group | 5,521 | 2 | 27,331 | 0.07 | 0.14 (0.03, 0.59) | 0.007 | 0.19 (0.04, 0.83) | 0.027 |
Group | n | Events (n) | Follow-up duration (PY) | Incidence rate (per 1,000 PY) | Crude HR (95% CI) | p-value | Adjusted |
p-value |
---|---|---|---|---|---|---|---|---|
Landmark analysis (follow-up after 1yr) | ||||||||
Infrequent group | 10,575 | 238 | 52,411 | 4.54 | 1.00 (reference) | 1.00 (reference) | ||
Occasional group | 9,476 | 93 | 46,506 | 2.00 | 0.44 (0.35, 0.56) | <0.001 | 0.62 (0.49, 0.80) | <0.001 |
Regular group | 5,514 | 31 | 27,253 | 1.14 | 0.25 (0.17, 0.36) | <0.001 | 0.41 (0.28, 0.60) | <0.001 |
Landmark analysis (follow-up after 2 yr) | ||||||||
Infrequent group | 10,343 | 174 | 52,060 | 3.34 | 1.00 (reference) | 1.00 (reference) | ||
Occasional group | 9,447 | 77 | 46,460 | 1.66 | 0.50 (0.38, 0.66) | <0.001 | 0.73 (0.55, 0.96) | <0.001 |
Regular group | 5,510 | 27 | 27,245 | 0.99 | 0.30 (0.20, 0.45) | <0.001 | 0.50 (0.33, 0.76) | <0.001 |
Values are presented as number (%) or mean±standard deviation.
PY, person-years; HR, hazard ratio; CI, confidence interval. The model was adjusted for age, sex, income level, residence, hypertension, diabetes, dyslipidemia, myocardial infarction, depression, and Charlson comorbidity index.
PY, person-years; HR, hazard ratio; CI, confidence interval. The model was adjusted for age, sex, income level, residence, hypertension, diabetes, dyslipidemia, myocardial infarction, depression, and Charlson comorbidity index.