Twenty-five years of the TARF study: The 2015 survey, and temporal trends in mortality and loss to follow-up

OBJECTIVE
The aims of the present study were to examine, first, overall mortality in the Turkish Adult Risk Factor (TARF) 2015 survey, and second, distribution of cumulative mortality and temporal losses to follow-up in the 7 geographic regions of Turkey over 25 years.

METHODS
Information on mode of death was obtained from first-degree relatives and/or primary health center personnel. Information regarding survivors was based on history, examination of the cardiovascular system, and Minnesota coding of electrocardiograms.

RESULTS
Of the 1304 participants to be screened, 58 were lost to follow-up, 787 were examined, and 39 participants had died. In 420 subjects, verbal reporting alone was used to determine health status. Deaths were attributed to coronary heart disease in 16 subjects, and cerebrovascular event and cancer in 8 cases each. However, evidence suggested underlying autoimmune activation in 85% of cases. Cumulative 25-year assessment of the entire cohort, comprising 863 deaths over a mean follow-up of 20.5 years, corresponded to a rate of 11.4 per 1000 person-years. A significantly lower mortality rate was found in the Southeast. The 1992 participants lost to follow-up represented a rate of 22.5 per 1000 person-years.

CONCLUSION
The generally high overall mortality in Turkey is similar among geographic regions, with the exception of a lower rate in Southeastern Anatolia. One of every 45 surviving participants is lost to follow-up each year.