Every row of the evidence table

The two measures moved in opposite directions over 2015-2021: standardised incidence fell from 3.5% to 2.8% per year while prevalence rose from 10.5% to 11.8%; gaps between Black or Hispanic and White beneficiaries narrowed.

Direction is for later birth cohort: each successive cohort had a significantly lower incident dementia rate, independent of sex, education and age.

Direction is for later calendar epoch: incidence fell 44% from the first to the fourth epoch, but only among people with at least a high school diploma. The authors could not fully explain the decline.

Incidence was consistently but non-significantly lower in the 2000 subcohort (rate ratio 0.75, 95% CI 0.56-1.02, borderline). The authors read the pattern, together with lower mortality and larger brain volumes, as suggesting a decline, but the primary comparison did not reach significance.

Direction is for degenerative pathology profiles: more than 80% had mixed pathologies, and of five clustered profiles the LATE-NC/hippocampal sclerosis and the ADNC/amyloid angiopathy profiles showed the fastest cognitive decline.

Direction is for LATE-NC: found in 64% of brains, stages 1a, 2 and 3 were associated with dementia and lower MMSE, it was among the strongest independent predictors of dementia, and its attributable risk (24.2%) exceeded that of Alzheimer's neuropathologic change (18.6%); it usually occurred alongside other pathologies.

Direction is for carrying the risk factors. The Danish estimate (37.8% across 16 factors) is lower than the Lancet Commission's global 45%.

Direction is for carrying the risk factors: depression, diabetes, low education, smoking, obesity, physical inactivity and alcohol overconsumption each independently raised the hazard of early-onset dementia, and most associations were stronger for early-onset than late-onset dementia.

Direction is for carrying the risk factors. Which factor mattered most differed by APOE risk group, on 2,065 cases split across 11 factors and three genetic strata, so the subgroup estimates are imprecise.

Direction is for carrying hypertension, diabetes or smoking. The attributable share rose with the age at which the factors were measured (22% at 45-54, 44% at 65-74), which is what you would expect if some of it is reverse causation rather than cause.

Direction is for carrying the risk factors. 39 candidate factors were screened against 485 cases, so individual estimates are imprecise.

For the vascular risk factors: up to a quarter of the education-dementia association ran through hypertension, diabetes and related midlife factors, so carrying them accounted for part of the excess risk.

A lifetime-risk estimate (42% after age 55, higher in women, Black adults and APOE4 carriers) and a projection of new cases. It compares no exposure, so no direction is recorded.

Direction is for being African-American or American Indian/Alaska Native relative to Asian-American members: incidence was highest in those groups (26.6 and 22.2 per 1000 person-years) and lowest in Asian-Americans (15.2). The authors present this as a benchmark for reducing disparities, not as a biological effect of race.

Direction is for female sex: at higher amyloid levels women had higher plasma p-tau217 than men, greater tau deposition and accumulation at a given p-tau217 level, and faster cognitive decline in two of the cohorts.