Independent and joint associations of cardiorespiratory fitness and BMI with dementia risk: the Cooper Center Longitudinal Study.
BMJ Open
; 13(12): e075571, 2023 12 12.
Article
in En
| MEDLINE
| ID: mdl-38086580
ABSTRACT
OBJECTIVE:
This study aimed to examine the association of midlife fitness and body mass index (BMI) with incident dementia later in life. DESIGN ANDPARTICIPANTS:
A cohort study of 6428 individuals (mean age 50.9±7.6 years) from the Cooper Center Longitudinal Study.MEASURES:
Cardiorespiratory fitness and BMI were assessed twice (1970-1999) during visits to the Cooper Clinic, a preventive medicine clinic in Dallas, Texas. These measures were examined as continuous and categorical variables. As continuous variables, fitness and BMI were examined at baseline (averaged of two examinations) and as absolute change between exams (mean time 2.1±1.8 years). Variables were categorised unfit versus fit and normal versus overweight/obese. Medicare claims data were used to obtain all-cause dementia incidence (1999-2009). Mean follow-up between midlife examinations and Medicare surveillance was 15.7 ((SD=6.2) years. Multivariable models were used to assess the associations between fitness, BMI and dementia.RESULTS:
During 40 773 person years of Medicare surveillance, 632 cases of dementia were identified. After controlling for BMI and covariates, each 1-metabolic equivalent increment in fitness was associated with 5% lower (HR 0.95; 95% CI 0.90 to 0.99) dementia risk. In comparison, after controlling for fitness and covariates, each 1 kg/m2 increment in BMI was associated with a 3.0% (HR 1.03; 95% CI 1.00 to 1.07) higher risk for dementia, yet without significance (p=0.051). Similar findings were observed when the exposures were categorised. Changes in fitness and BMI between examinations were not related to dementia. Jointly, participants who were unfit and overweight/obese had the highest (HR 2.28 95% CI 1.57 to 3.32) dementia risk compared with their fit and normal weight counterparts.CONCLUSION:
Lower midlife fitness is a risk marker for dementia irrespective of weight status. Being unfit coupled with overweight/obese status might increase one's risk for dementia even further.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Dementia
/
Cardiorespiratory Fitness
Limits:
Adult
/
Aged
/
Humans
/
Middle aged
Country/Region as subject:
America do norte
Language:
En
Journal:
BMJ Open
Year:
2023
Document type:
Article
Affiliation country:
Israel