Biological Age Affecting Attrition and Tooth Loss in a Follow-up Study.

Area of Science:

• Gerontology and Public Health
• Biomarkers and Aging Research
• Dental Epidemiology

Background:

• Longitudinal studies face bias from participant nonresponse and attrition.
• Attrition significantly impacts the validity of conclusions drawn from population-based research.
• This issue is particularly under-addressed in dental research, necessitating investigation.

Purpose of the Study:

• To examine the consequences of attrition on tooth loss and mortality in a 10-year follow-up study.
• To assess the role of biological age (BA) in predicting attrition and its impact on health outcomes.
• To understand how attrition affects the generalizability of findings from longitudinal dental studies.

Main Methods:

• Constructed a biological age (BA) score from 10 systemic biomarkers in the Study of Health in Pomerania (SHIP-0).
• Stratified 3,417 dentate participants into tertiles based on BA relative to chronological age (CA).
• Compared baseline characteristics, attrition propensity, and tooth loss in relation to BA-CA strata over a 10-year follow-up (SHIP-2).

Main Results:

• Attrition propensity was dose-dependent on BA-CA scores and socioeconomic factors.
• Participants with younger BA were underrepresented in dropouts and overrepresented in follow-up participants.
• Younger BA individuals exhibited a more favorable risk profile, better oral health, and lower mortality; their tooth retention was influenced by baseline BA.

Conclusions:

• Individual risk profiles aggregated in BA predict susceptibility to attrition in long-term studies.
• Attrition alters study participant composition based on BA, affecting results' transferability to the baseline population.
• The baseline BA gradient persists over time, highlighting its enduring influence on health outcomes and study participation.