Active Modes of Transport May Protect Against Dementia

 I biked 3 miles to and from work for 20+ years 9 months out of the year prior to my stroke. Nothing really since then, will that earlier biking be enough to prevent dementia? AND WHY DOESN'T ANYONE KNOW THAT ANSWER?

Active Modes of Transport May Protect Against Dementia

Cycling was associated with lower risk for all-cause dementia, underscoring the potential public health benefits of promoting active travel strategies.Cycling is associated with reduced risk for all-cause dementia, according to results of a study published in JAMA Network Open< Researchers used data from the United Kingdom Biobank to examine long-term associations between mode of transportation and incidence of young-onset (diagnosis at <65 years of age) and late-onset (diagnosis at ≥65 years of age) dementia. Secondary outcomes included dementia subtype and brain structure. Cox proportional hazards regression models were used for statistical analysis, and magnetic resonance imaging was used to measure brain structure. A total of 479,723 patients were included in the study. Among them, 49.1% used nonactive transportation, 37.0% combined walking with nonactive transportation (mixed-walking), 7.0% cycled with or without nonactive transportation, and 6.8% walked only. Mean (SD) ages among these groups were 56.4 (8.0), 57.1 (8.1), 54.5 (8.3), and 56.0 (8.0) years, respectively. The percentage of women in each group was 54.0%, 57.8%, 36.9%, and 56.0%. Mean (SD) BMI for each group was 28.0 (5.0), 27.1 (4.6), 25.9 (3.8), and 26.5 (4.4) kg/m. Lastly, 28.2%, 28.6%, 28.8%, and 28.5% were carriers of apolipoprotein E (APOE) e4, respectively.

During a median follow-up of 13.1 (IQR, 12.8-13.5) years, 1.8% of the study population were diagnosed with dementia, including 0.2% with young-onset dementia, 2.5% with late-onset dementia, and 0.8% with Alzheimer disease.

The findings of this cohort study suggest that active travel modes, particularly cycling and mixed-cycling, are associated with a reduced incidence of dementia (YOD and LOD) and AD and greater hippocampal volume. These results may offer a promising approach to better brain health and lower dementia risk.

Stratified by transportation method, the incidence rate of all-cause dementia per 100,000 person-years was 147.2 for nonactive transportation, 141.5 for mixed-walking, 86.4 for cycling, and 145.8 for walking. Compared with nonactive transportation, risk for all-cause dementia was significantly lower with cycling (adjusted hazard ratio [aHR], 0.81; 95% CI, 0.73-0.91) and mixed-walking (aHR, 0.94; 95% CI, 0.89-0.98). Moreover, among individuals with nonactive transportation, the subset of individuals who traveled by car (aHR, 0.78; 95% CI, 0.72-0.85) or both car and public transportation (aHR, 0.81; 95% CI, 0.73-0.91) had significantly lower risk for all-cause dementia relative to those who only used public transportation.

Stratified by dementia type, cycling was associated with lower risk for young-onset dementia (aHR, 0.60; 95% CI, 0.38-0.95), late-onset dementia (aHR, 0.83; 95% CI, 0.75-0.93), and Alzheimer disease (aHR, 0.78; 95% CI, 0.66-0.92). Mixed-walking was associated with reduced risk for late-onset dementia (aHR, 0.94; 95% CI, 0.89-0.98), while walking was associated with a higher risk for Alzheimer disease (aHR, 1.14; 95% CI, 1.01-1.29).

Among the subset of individuals with magnetic resonance imaging data (n=44,801), cycling was associated with greater gray matter volumes in 10 brain regions (d, 0.004-0.108; P <.05) and larger hippocampal volumes (b, 0.05; 95% CI, 0.02-0.08). Conversely, smaller gray matter volumes were associated with walking (b, -0.06; 95% CI, -0.09 to -0.03) and mixed-walking (b, -0.02; 95% CI, -0.04 to -0.01). Additionally, mixed-walking was associated with less white matter (b, -0.02; 95% CI, -0.043 to -0.004).

The protective effect of cycling on all-cause dementia (hazard ratio [HR], 0.74; 95% CI, 0.63-0.87) and late-onset dementia (HR, 0.75; 95% CI, 0.63-0.89) risk was only observed among individuals who did not carry APOE e4.

Study limitations include the small number of young-onset dementia cases, limiting statistical power.

The study authors concluded, “The findings of this cohort study suggest that active travel modes, particularly cycling and mixed-cycling, are associated with a reduced incidence of dementia ([young-onset dementia] and [late-onset dementia]) and [Alzheimer disease] and greater hippocampal volume. These results may offer a promising approach to better brain health and lower dementia risk.”

References: