title: Association of telomere length in older men with mortality and midlife body mass index and smoking.
abstract: BACKGROUND
  Leukocyte telomere length has been taken as a measure of biological age but several inconsistencies exist.
  
  
  METHODS
  We investigated associations between leukocyte telomere length in old age, midlife risk factors, and mortality. The Helsinki Businessmen Study (a cohort of mainly business executives, born 1919-1934) had baseline assessments of cardiovascular risk factors including body mass index between 1964 and 1973 at a mean age of 40. Leukocyte telomere length and proportion of short telomeres were measured from DNA samples collected in 2002-2003 (n = 622, mean age 78 years). Body mass index and smoking in old age were assessed from questionnaires. Total mortality was verified from registers through January 2010. Main outcome measures were relationships between telomeres, body mass index, smoking, and mortality.
  
  
  RESULTS
  Leukocyte telomere length and notably proportion of short telomeres (<5kb) in old age were significantly (p =. 008 after full adjustments) and in a graded manner associated with midlife overweight and smoking. The associations were independent of age and cardiovascular risk factors including postload glucose. Associations with body mass index and smoking were nonsignificant in old age, and telomere length did not predict 7-year total mortality.
  
  
  CONCLUSIONS
  We conclude that smoking and overweight in midlife, irrespective of glucose, cholesterol and blood pressure, are related to shorter leukocyte telomeres in old men. Telomere length in old age did not predict total mortality possibly due to competing causes.
authors.affiliation: Unit of General Practice, Institute of Health Sciences/Geriatrics, University of Oulu and University Hospital, Finland. timo.strandberg@oulu.fi
authors.forename: Timo E
authors.initials: TE
authors.lastname: Strandberg
authors.forename: Outi
authors.initials: O
authors.lastname: Saijonmaa
authors.forename: Reijo S
authors.initials: RS
authors.lastname: Tilvis
authors.forename: Kaisu H
authors.initials: KH
authors.lastname: Pitkälä
authors.forename: Arto Y
authors.initials: AY
authors.lastname: Strandberg
authors.forename: Tatu A
authors.initials: TA
authors.lastname: Miettinen
authors.forename: Frej
authors.initials: F
authors.lastname: Fyhrquist
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000235:genetics*; D015139:Blotting, Southern; D015992:Body Mass Index; D002318:Cardiovascular Diseases / Q000209:etiology / Q000235:genetics* / Q000401:mortality; D004247:DNA / Q000032:analysis* / Q000235:genetics; D005387:Finland / Q000453:epidemiology; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D050177:Overweight / Q000209:etiology / Q000235:genetics* / Q000401:mortality; D012189:Retrospective Studies; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects* / Q000235:genetics / Q000401:mortality; D011795:Surveys and Questionnaires; D015996:Survival Rate / Q000639:trends; D016615:Telomere / Q000737:chemistry* / Q000235:genetics; D013997:Time Factors
chemical_list: D004247:DNA