A recent study published in BMC Geriatrics has revealed the global prevalence of mild cognitive impairment and examined the key factors influencing its development
Mild cognitive impairment is when a person experiences a slight but noticeable decline in mental abilities, such as memory and thinking skills, greater than expected for their age but not severe enough to interfere significantly with daily life. It is recognised as a clinical and transitional stage between healthy ageing and dementia.
To assess the worldwide impact of mild cognitive impairment and the influences driving this, researchers reviewed 51 high-quality existing studies.
A Nepal study found the highest recorded rate of mild cognitive impairment among the elderly, at 93%
Of the 1,180 studies, 336 duplicates were removed. After screening and quality checks, 51 high-quality studies were included in the meta-analysis.
The researchers analysed a sample of 287,689 older adults, and the I² index indicated high heterogeneity. As a result, the Random Effect Model was used for the meta-analysis.
Following a meta-analysis, the highest prevalence of mild cognitive impairment (93%) in the geriatric population was related to the study of Pradhan et al., in Nepal, and the lowest index (1.7%) was associated with the study of Khedr et al. in Egypt. Across the studies, the global prevalence of mild cognitive impairment in the geriatric population was reported as 23.7%.
Key risk factors in the elderly: Education, age, and depression
Based on relevant studies, some critical factors, including education levels, age range, and depression, were considered as intervening factors in the occurrence of this impairment.
Seven studies identified the educational level as a relevant factor for developing mild cognitive impairment. In this regard, a low education level was considered a primary risk factor for this.
According to nine studies, age is associated with the occurrence rate of mild cognitive impairment. Thus, higher age groups are more susceptible to mild cognitive impairment. Four studies stated that depression is a considerably influential factor for mild cognitive impairment in the geriatric population. In this regard, other risk factors include low socioeconomic status, stroke, high blood pressure, low physical activity, and female gender.
Valuable insights for health policymakers
The findings underscore that this condition is a progressive but not always irreversible condition. Some individuals may progress to dementia, and others remain stable or revert to normal mental functioning.
Non-pharmacological strategies such as cognitive interventions, lifestyle modifications, and preventive care are recommended without approved pharmacological treatments.
Importantly, these findings offer valuable insights for health policymakers, supporting the need to raise awareness among older adults and their caregivers and to promote regular cognitive screening as a preventive measure against the development of mild cognitive impairment.
Study limitations
One of the main limitations of this analysis was that most of the included studies were conducted in Asia. Future research should explore this impairment in other continents to ensure broader global representation and generalisability of findings. Furthermore, the analysis was performed in English-based languages. Therefore, any non-English articles with no English abstracts were excluded due to the inaccessibility of all parts of the article.
Another limitation of this study is the variation in diagnostic cut-off points used across studies to assess cognitive impairment in the elderly. Many of the included studies did not adhere to Petersen’s criteria, leading to inconsistencies in the definition and measurement of cognitive impairment. Additionally, using different cognitive assessment tools with varying thresholds suggests that cognitive impairment was managed and interpreted independently across studies.
