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Yoro-Zohoun et al. (2021) investigated the association between the apolipoprotein E (APOE) ε4 allele and neuropsychiatric symptoms (NPS) in 322 older adults from Central Africa. The sample had a high prevalence of the APOE ε4 allele, with 40% of older adults having at least one ε4 allele. Interestingly, participants who were homozygous APOE ε4 allele carriers had less NPS in the previous 30 days compared to noncarriers in an analysis adjusted for sociodemographic variables and cognitive status. Non-significant trends were also found in participants who were heterozygous for the APOE ε4 allele, suggesting lower odds of NPS among these participants compared to nonAPOE ε4 allele carriers. Based on studies in white populations, the APOE ε4 allele is the strongest genetic risk factor for Alzheimer’s disease (AD), with evidence suggesting that APOE status influences β-amyloid aggregation and clearance (Kim et al., 2009). Although the APOE ε4 allele was shown to be a risk factor for AD among individuals with African ancestry in a recent large, genome-wide association study (Kunkle et al., 2020), the effect of the APOE ε4 allele on dementia risk among these individuals seems to be weaker than in white individuals (Barnes and Bennett, 2014). The study by Yoro-Zohoun et al. (2021) reports that 40% of the 322 older adults in a sample from Central African had at least one ε4 allele, which is similar to that found by Evans et al. in the USA among black participants (42%) but higher than among white participants (27%) (Evans et al., 2003). However, African Americans showed a weaker association between the APOE ε4 allele and cognitive decline and AD than that found in the white participants (Evans et al., 2003). Moreover, in a study comparing this association among African Americans and Yoruba, the association between the APOE ε4 allele with AD incidence and cognitive decline was weaker in the Yoruba people than in the African Americans (Hendrie et al., 2014). The frequency of β-amyloid accumulation seems to be lower in individuals with African ancestry, suggesting that the weaker effect of APOE on cognitive outcomes could be mediated by lower β-amyloid deposition (Schlesinger et al., 2013). In line with this finding, compared to white participants, lower concentrations of AD biomarkers have been found in the cerebrospinal fluid of African Americans who had at least one APOE ε4 allele compared to non-Hispanic whites and African Americans without ε4 alleles (Morris et al., 2019). NPSs are common during the course of dementia and are an important source of burden for patients with dementia and their caregivers (Sink et al., 2005). In older people without dementia, some, but not all NPS, seem to be associated with dementia incidence and cognitive decline (Brodaty et al., 2012). In a study that included 873 community dwelling adults aged 70–90 years in Australia, only baseline depression was associated with dementia at follow-up and only anxiety and agitation were significantly associated with cognitive decline, while overall rates of NPS at baseline were not associated with mild cognitive impairment (MCI), dementia, or cognitive decline over the 2 years follow-up (Brodaty et al., 2012). In Mexico, however, a study conducted with 1355 older adults (Acosta et al., 2018) found that five NPSs (delusions, hallucinations, anxiety, aberrant motor behavior and depression) were associated with dementia incidence over a period of 3 years follow-up and the risk increased with the increased number of symptoms. These increased risks may be influenced by APOE ε4. Pink et al. (2015) found that among 332MCI cases, baseline agitation, nighttime behaviors, depression, and apathy elevated the risk of incident dementia, and there was a synergistic interaction of depression and apathy with APOE ε4 in further elevating the risk of incident dementia. The investigation of risk factors for NPS is essential to promote patient and caregiver well-being, and the hypothesis that the APOE ε4 allele could be a risk factor for NPS in older populations is reasonable. However, current evidence on the association between NPS and the APOE ε4 allele is mixed (Panza et al., 2012), and most studies have been conducted in white populations with clinical dementia. Studies on individuals with African ancestry and in cognitively normal individuals are scarce. Yoro-Zohoun et al. investigated the association between APOE ε4 and NPS and found less participants with at least one NPS in the last 30 days among those who were homozygous for the ε4 allele, and a trend of less participants with at least one NPS International Psychogeriatrics (2021), 33:3, 213–215 © International Psychogeriatric Association 2021