Title | Survival advantage of cohort participation attenuates over time: results from three long-standing community-based studies. |
Publication Type | Journal Article |
Year of Publication | 2020 |
Authors | Zheng Z, Rebholz CM, Matsushita K, Hoffman-Bolton J, Blaha MJ, Selvin E, Wruck L, Sharrett ARichey |
Secondary Authors | Coresh JJ |
Journal | Ann Epidemiol |
Volume | 45 |
Pagination | 40-46.e4 |
Date Published | 2020 05 |
ISSN | 1873-2585 |
Keywords | Aged, Atherosclerosis, Cohort Studies, Community-Based Participatory Research, Epidemiologic Studies, Female, Heart Diseases, Humans, Male, Maryland, Middle Aged, Mortality, Neoplasms, Risk Factors, Selection Bias, Stroke, United States |
Abstract | PURPOSE: Cohort participants usually have lower mortality rates than nonparticipants, but it is unclear if this survival advantage decreases or increases as cohort studies age. METHODS: We used a 1975 private census of Washington County, Maryland, to compare mortality among cohort participants to nonparticipants for three cohorts, Campaign Against Cancer and Stroke (CLUE I), Campaign Against Cancer and Heart Disease (CLUE II), and Atherosclerosis Risk In Communities (ARIC) initiated in 1974, 1989, and 1986, respectively. We analyzed mortality risk using time-truncated Cox regression models. RESULTS: Participants had lower mortality risk in the first 10 years of follow-up compared with nonparticipants (fully adjusted average hazard ratio [95% confidence intervals] were 0.72 [0.68, 0.77] in CLUE I, 0.69 [0.65, 0.73] in CLUE II, and 0.74 [0.63, 0.86] in ARIC), which persisted over 20 years of follow-up (0.81 [0.78, 0.84] in CLUE I, 0.87 [0.84, 0.91] in CLUE II, and 0.90 [0.83, 0.97] in ARIC). This lower average hazard for mortality among participants compared with nonparticipants attenuated with longer follow-up (0.99 [0.96, 1.01] after 30+ years in CLUE I, 1.02 [0.99, 1.05] after 30 years in CLUE II, and 0.95 [0.89, 1.00] after 30+ years in ARIC). In ARIC, participants who did not attend visits had higher mortality, but those who did attend visits had similar mortality to the community. CONCLUSIONS: Our results suggest the volunteer selection for mortality in long-standing epidemiologic cohort studies often diminishes as the cohort ages. |
DOI | 10.1016/j.annepidem.2020.03.010 |
Alternate Journal | Ann Epidemiol |
PubMed ID | 32371044 |
PubMed Central ID | PMC7294871 |
Grant List | R01 DK089174 / DK / NIDDK NIH HHS / United States K01 DK107782 / DK / NIDDK NIH HHS / United States R21 HL143089 / HL / NHLBI NIH HHS / United States HHSN268201700002C / HL / NHLBI NIH HHS / United States HHSN268201700001I / HL / NHLBI NIH HHS / United States HHSN268201700004C / HL / NHLBI NIH HHS / United States HHSN268201700003I / HL / NHLBI NIH HHS / United States K24 DK106414 / DK / NIDDK NIH HHS / United States HHSN268201700004I / HL / NHLBI NIH HHS / United States HHSN268201700005C / HL / NHLBI NIH HHS / United States HHSN268201700001C / HL / NHLBI NIH HHS / United States HHSN268201700003C / HL / NHLBI NIH HHS / United States HHSN268201700002I / HL / NHLBI NIH HHS / United States HHSN268201700005I / HL / NHLBI NIH HHS / United States |