Competing risks analysis, adjusted for age, sex and Index of Multiple Deprivation (IMD).

Competing risks analysis, adjusted for age, sex and Index of Multiple Deprivation (IMD).</p

Regression analyses using multiply imputed data, adjusted for age, sex and Index of Multiple Deprivation (IMD).

Regression analyses using multiply imputed data, adjusted for age, sex and Index of Multiple Deprivation (IMD).</p

Flow chart for included participants.

Baseline demographic characteristics and risk factor status for the sample are shown in Table 1. South Asian and Black people were on average younger than White people (mean age 69.4 and 69.7 respectively compared to 70.9) and there was a lower percentage of South Asian women (50.8%) compared to White (54.4%) and Black women (56.1%). A greater percentage of South Asian and Black people lived in more deprived areas (18.8% and 35.7% in the most deprived quintile) compared to White people (14.2% in most deprived quintile). Hypertension was most common in Black people (70.7%), followed by South Asians (66.0%) and with the lowest percentage of hypertension in White people (63.0%). The same pattern was seen for obesity– 34.2%, 22.8% and 19.2% in Black, South Asian and White people respectively. Hearing loss was least common in Black people with similar rates in White and South Asian people. Smoking rates were similar in White and South Asian people, but Black people had very low rates of smoking. Excess alcohol use was least common in South Asian people, and most common in White people. Diabetes was three times more common in South Asian people and more than twice as common in Black people than White people. Dyslipidaemia, low HDL and high LDL were all more common in South Asian and Black people than in White people. Sleep disorders were similarly prevalent in White and South Asian people and least common in Black people. Brain injury was recorded with similar frequency across all ethnic groups.</p

Supplementary tables and analyses.

IntroductionWe aimed to investigate ethnic differences in the associations of potentially modifiable risk factors with dementia.MethodsWe used anonymised data from English electronic primary care records for adults aged 65 and older between 1997 and 2018. We used Cox regression to investigate main effects for each risk factor and interaction effects between each risk factor and ethnicity.ResultsWe included 865,674 people with 8,479,973 person years of follow up. Hypertension, dyslipidaemia, obesity and diabetes were more common in people from minority ethnic groups than White people. The impact of hypertension, obesity, diabetes, low HDL and sleep disorders on dementia risk was increased in South Asian people compared to White people. The impact of hypertension was greater in Black compared to White people.DiscussionDementia prevention efforts should be targeted towards people from minority ethnic groups and tailored to risk factors of particular importance.</div

Baseline demographic characteristics and risk factors of total complete case sample and divided into Black, South Asian and White ethnicity.

Baseline demographic characteristics and risk factors of total complete case sample and divided into Black, South Asian and White ethnicity.</p

Main effects and interaction effects.

IntroductionWe aimed to investigate ethnic differences in the associations of potentially modifiable risk factors with dementia.MethodsWe used anonymised data from English electronic primary care records for adults aged 65 and older between 1997 and 2018. We used Cox regression to investigate main effects for each risk factor and interaction effects between each risk factor and ethnicity.ResultsWe included 865,674 people with 8,479,973 person years of follow up. Hypertension, dyslipidaemia, obesity and diabetes were more common in people from minority ethnic groups than White people. The impact of hypertension, obesity, diabetes, low HDL and sleep disorders on dementia risk was increased in South Asian people compared to White people. The impact of hypertension was greater in Black compared to White people.DiscussionDementia prevention efforts should be targeted towards people from minority ethnic groups and tailored to risk factors of particular importance.</div

Stratified analysis for risk factors with statistically significant interaction terms.

Stratified analysis for risk factors with statistically significant interaction terms.</p

The RECORD statement–Checklist of items, extended from the STROBE statement, that should be reported in observational studies using routinely collected health data.

The RECORD statement–Checklist of items, extended from the STROBE statement, that should be reported in observational studies using routinely collected health data.</p

Regression analyses including adjustment for modified Charlson index, as well as age, sex and Index of Multiple Deprivation (IMD).

Regression analyses including adjustment for modified Charlson index, as well as age, sex and Index of Multiple Deprivation (IMD).</p