DESK REVIEWS | 06.02.07. Is there evidence for difference in incidence/prevalence by gender and for different ethnic groups?

DESK REVIEW | 06.02.07. Is there evidence for difference in incidence/prevalence by gender and for different ethnic groups?

Yes. According to a systematic review conducted in 2011 (Fagundes et al., 2011), the prevalence of dementia was higher among women in all studies selected. The authors of this systematic review acknowledge that the age distribution of the sample populations was not uniform, which may explain the variation in the prevalence of dementia that was detected, as women tend to live eight years longer than men on average in Brazil, and, therefore, would contribute more to the prevalence rates of dementia. The review also showed that the prevalence of dementia increased with age and was inversely related to the socioeconomic status and number of years of education.

References:

Fagundes, S. D., Silva, M. T., Thees, M. F. R. S., & Pereira, M. G. (2011). Prevalence of dementia among elderly Brazilians: A systematic review. Sao Paulo Medical Journal, 129(1), 46–50. https://doi.org/10.1590/S1516-31802011000100009

There is evidence of differences in dementia prevalence by gender. A study further estimates the difference in prevalence of very mild and mild dementia by gender for people aged 60 and over and people aged 70 and over. For mild dementia, the prevalence for female and male aged 60 and above were 7.6% and 3.1% respectively; and for female and male aged 70 or above were 12.3% and 5.0% respectively (Lam et al., 2008). However, there is no data regarding the difference in dementia prevalence on different ethnic groups in Hong Kong.

References:

Lam, L. C., Tam, C. W., Lui, V. W., Chan, W., Chan, S. S., Wong, S., . . . Chiu, H. (2008). Prevalence of very mild and mild dementia in community-dwelling older Chinese people in Hong Kong. International Psychogeriatrics, 20(1), 135-148. https://doi.org/10.1017/S1041610207006199

Prevalence by age/gender

The GBD (India State-Level Disease Burden Initiative Neurological Disorders Collaborators, 2021) study provides a breakdown of dementia prevalence as per age and gender, demonstrating higher prevalence of dementia among women than men in India. This is available on Page 125 of the Supplementary document: https://www.thelancet.com/cms/10.1016/S2214-109X(21)00164-9/attachment/26ff536c-3eec-45f7-897a-183dc4e7777e/mmc1.pdf

Prevalence by ethnic groups

The prevalence of dementia across ethnic groups has not been widely studied in India. One study conducted in the state of Jammu and Kashmir examined the prevalence of dementia among the ethnic Dogra population compared to the migrant Kashmiri Pandit population (Raina, Razdan and Pandita, 2010; Raina et al., 2008). The study reported overall prevalence of dementia in those aged 60 and over as 1.83% in the ethnic Dogra population, which was lower than the prevalence rate among the migrant Kashmiri Pandits (6.5%) reported in an earlier study (Raina, Razdan and Pandita, 2010, Raina et al., 2008).

References:

India State-Level Disease Burden Initiative Neurological Disorders Collaborators (2021). The burden of neurological disorders across the states of India: The Global Burden of Disease Study 1990-2019. The Lancet. Global health, 9(8), e1129–e1144.

Raina, S. K., Razdan, S., & Pandita, K. K. (2010). Prevalence of dementia in ethnic Dogra population of Jammu district, North India: a comparison survey. Neurology Asia15(1).

Raina, S., Raina, S., Razdan, S., & Pandita, K. (2008). Prevalence of dementia among Kashmiri migrants. Annals of Indian Academy of Neurology, 11(2), 106. https://doi.org/10.4103/0972-2327.41878

Data from the studies in both Yogyakarta and Bali showed a higher prevalence of dementia in women (22.0% and 38%, respectively) than men (17.9% and 25.7%, respectively) (Suriastini et al., 2016, 2018). This is consistent with other, international data on dementia, which suggests that this condition affect more women than men (Erol et al., 2015).

We found no data on differences between ethnic groups.

References:

Erol, R., Brooker, D., & Peel, E. (2015). Women and Dementia A global research review. 52.

Suriastini, Turana, Y., Sukadana, W., Sikoki, B., Witoelar, F., Lesmana, C. B. J., Mulyanto, E. D., Hermoko, R., & Anandari, G. A. A. A. (2018). Menggugah Lahirnya Kebijakan Kelanjutusiaan Menggugah Lahirnya Kebijakan Kelanjutusiaan.

Suriastini, Turana, Y., Witoelar, F., Supraptilah, B., Wicaksono, T., & Dwi, E. (2016). Policy Brief Angka Prevalensi Demensia: Perlu Perhatian Kita Semua. SurveyMETER, Maret, 1–4.

 

Eldemire-Shearer and colleagues (2018) found that the female gender (70.6%) was significantly associated with higher rates of dementia than males.

References:

Eldemire-Shearer, D., James, K., Johnson, P., Gibson. R., Willie-Tyndale, D. (2018). Dementia among Older Persons in Jamaica: Prevalence and Policy Implications. West Indian Medical Journal, 2018; 67 (1): 1. Available from: https://www.mona.uwi.edu/fms/wimj/system/files/article_pdfs/wimj-iss1-2018_1_8.pdf

There is currently no study in Kenya to our knowledge that has provided estimates of dementia incidence or prevalence by gender or ethnic groups. According to the Global Burden of Disease reported by Alzheimer’s Disease International (ADI) and WHO in 2012, the estimates of dementia prevalence in East Sub-Saharan Africa was  highest among those aged 85 years and above (16.3%), followed by those aged between 80 to 84 years (8.2%), then 75 to 79 years (4.3%), 70 to 74 years (2.3%), 65 to 69 years (1.2%) and the least percentage (0.6%) seen among those aged 60 to 64 years (Alzheimer’s Disease International (ADI) and World Health Organization (WHO), 2012).

References:

Alzheimer’s Disease International (ADI) and World Health Organization (WHO). (2012). Dementia: A public health priority. United Kingdom. https://www.alzint.org/u/2020/08/Dementia-A-Public-Health-Priority.pdf

According to ENSANUT dementia is more prevalent in women (9.1%) compared to men (6.9%). In MHAS, rate of dementia in women was higher compared to men (3.1 vs 2.1), adjusted by age.

Disaggregated data by ethnic groups is not yet available.

When discussing ethnicity, the Deloitte report comments that “While there is evidence that the incidence of dementia may be higher for Māori and Pacific peoples in New Zealand, due to a higher prevalence of cardiovascular risk factors, no data were available to enable modelling of the extent of this difference”. Cullum et al. (2018) findings also suggest a higher incidence/prevalence due to the increased burden of risk factors in Māori and Pacific people.

References:

Cullum S., Mullin K., Zeng I., Yates S., Payman V., Fisher M., et al. (2018). Do community-dwelling Maori and Pacific peoples present with dementia at a younger age and at a later stage compared with NZ Europeans? Int J Geriatr Psychiatry. 33(8):1098-104. https://doi.org/10.1002/gps.4898.

No nationally representative data on the prevalence or incidence of dementia. However, a smaller dementia prevalence study conducted in a rural, isiXhosa-speaking area in South Africa found no association with sex (De Jager et al., 2017). No representative data available to report on different ethnic groups (as study mentioned here did not have ethnic representativeness in sample).

References:

De Jager, C.A., Msemburi, W., Pepper, K., & Combrinck, M. (2017). Dementia Prevalence in a Rural Region of South Africa: A Cross-Sectional Community Study. Journal of Alzheimer’s Disease, 60(3), 1087–1096. https://doi.org/10.3233/JAD-170325