Consistency and applicability of different brief screen instrument of cognitive function in elderly population

Depressive Symptoms and Cognitive Decline Among Chinese Rural Elderly Individuals: A Longitudinal Study With 2-Year Follow-Up

Background

Depressive symptoms and mild cognitive impairment (MCI) are highly prevalent in rural China. The study aimed to investigate the longitudinal associations between changes in depressive symptoms and cognitive decline and MCI incidence among Chinese rural elderly individuals.

Methods

A 2-year follow-up study was conducted among 1,477 participants from the Anhui Healthy Longevity Survey (AHLS). Depressive symptoms were assessed by the 9-item Patient Health Questionnaire (PHQ-9), and cognitive status was evaluated by the Mini Mental State Examination (MMSE). Multivariable linear regression and logistic regression were employed.

Results

Every 1-unit PHQ-9 score increase was significantly associated with more cognitive decline (β = 0.157, 95% CI: 0.092, 0.221, p < 0.001) and a higher risk of MCI incidence (OR = 1.063, 95% CI: 1.025, 1.103, p = 0.001). The participants who experienced worsening of depression symptoms had a larger decline in the 2-year MMSE score (β = 0.650, 95% CI: 0.039, 1.261, p = 0.037) and elevated risks of incident MCI (OR = 1.573, 95% CI: 1.113, 2.223, p = 0.010).

Limitations

Screening tools rather than standard diagnostic procedures were used in the study. Moreover, the long-term associations still need further exploration since the follow-up time was short.

Conclusions

Increased depressive symptoms were associated with more cognitive decline and higher risks of incident MCI among Chinese rural residents.

Combined homocysteine and apoE rs429358 and rs7412 polymorphism in association with serum lipid levels and cognition in Chinese community-dwelling older adults

BACKGROUND

ApoE gene polymorphism and serum total homocysteine (tHcy) has been reportedly associated with cognition. In this study, we assessed the association of combined ApoE gene polymorphism and tHcy with cognition in Chinese elder adults.

METHODS

A cross- sectional study was carried out by recruiting 1458 community-dwelling people aged 55+ and above in Beijing in 2009. All participants were interviewed using a standard questionnaire and underwent a physical examination. The mini-mental scale examination (MMSE) score was used in assessing cognitive function. Fasting venous blood samples were taken for ApoE rs429358, rs7412 genotyping, tHcy and other serum lipid measurements.

RESULTS

Participants with high serum tHcy level showed a relatively lower orientation, attention abilities as well as the total MMSE score than the group with normal tHcy after adjusting confounding factors. ApoE rs429358 and rs7412 variants were observed to have the highest serum TC and TG level in the subjects with high serum tHcy level (p <  0.05). Cognition of the subjects was found to be significantly associated with high serum tHcy level and ApoE genetic polymorphism (p <  0.05). Independent of age, BMI, education levels, smoking and alcohol drinking, the worst cognitive ability were detected in the high serum tHcy level subjects with ApoE rs429358C/T and rs7412 C/T as compare with other groups, especially orientation function, memory and delayed recall ability and attention ability.

CONCLUSION

High serum tHcy level in combination with ApoE rs429358 and rs7412 variants might be linked with serum lipid levels and cognition, particularly for orientation function and memory and delayed recall ability in old Chinese adults.

Montreal Cognitive Assessment: Seeking a Single Cutoff Score May Not Be Optimal

Background

Cutoff scores of the Montreal cognitive assessment (MoCA) for screening mild cognitive impairment in older adults differ across the world and within the Chinese culture. It is argued that to seek a cutoff score is essential to classify test participants. It was unknown how taking a classifying approach might reveal the cutoff score for identifying mildly cognitively impaired older adults.

Methods

Participants, selected from 13 communities in Wuhan, China, were tested with the Chinese version of MoCA and rated with the Activities of Daily Living and the Clinical Dementia Rating scales. Mixture modeling was applied to the data with certain covariates and MoCA sum scores as the outcome of the latent class. Models with different numbers of classes were compared in terms of information criteria, likelihood ratio test, entropy, and interpretability.

Results

A 3-class model (normal, mildly impaired, and severely impaired) was found to fit the data best. The normal class averaged a MoCA score of 24, while the severely impaired class averaged a score below 18. For those cases with MoCA scores above 18 and below 24, it is not certain if they are in the normal or the severely impaired classes.

Conclusion

Latent variable classification modeling provides another option to identify MCI in older adults. Some categorically different cases of MCI cannot be captured with any single MoCA sum score. A range of 18–24 MoCA scores might serve as a better screening criterion of MCI. Older adults who scored within this gray zone should be monitored for potential interventions.