Long-term iodine nutrition is associated with longevity in older adults: a 20 years' follow-up of the Randers-Skagen study.
Br J Nutr
; 125(3): 260-265, 2021 02 14.
Article
in En
| MEDLINE
| ID: mdl-32378500
ABSTRACT
Iodine intake affects the occurrence of thyroid disorders. However, the association of iodine intake with longevity remains to be described. This led us to perform a 20 years' follow-up on participants from the Randers-Skagen (RaSk) study. Residents in Randers born in 1920 (n 210) and Skagen born in 1918-1923 (n 218) were included in a clinical study in 1997-1998. Mean iodine content in drinking water was 2 µg/l in Randers and 139 µg/l in Skagen. We collected baseline data through questionnaires, performed physical examinations and measured iodine concentrations in spot urine samples. Income data were retrieved from Danish registries. We performed follow-up on mortality until 31 December 2017 using Danish registries. Complete follow-up data were available on 428 out of 430 of participants (99·5 %). At baseline, the median urinary iodine concentration was 55 µg/l in Randers and 160 µg/l in Skagen residents. Participants were long-term residents with 72·8 and 92·7 % residing for more than 25 years in Randers and Skagen, respectively. Cox regression showed that living in Skagen compared with Randers was associated with a lower hazard ratio (HR) of death in both age- and sex-adjusted analyses (HR 0·60, 95 % CI 0·41, 0·87, P = 0·006), but also after adjustment for age, sex, number of drugs, Charlson co-morbidity index, smoking, alcohol and income (HR 0·60, 95 % CI 0·41, 0·87, P = 0·008). Residing in iodine-replete Skagen was associated with increased longevity. This indicates that long-term residency in an iodine-replete environment may be associated with increased longevity compared with residency in an iodine-deficient environment.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Trace Elements
/
Nutritional Status
/
Iodine
/
Longevity
Type of study:
Observational_studies
/
Prognostic_studies
/
Risk_factors_studies
Limits:
Aged
/
Aged80
/
Female
/
Humans
/
Male
Country/Region as subject:
Europa
Language:
En
Journal:
Br J Nutr
Year:
2021
Document type:
Article
Affiliation country: