Effect of low dose ω-3 poly unsaturated fatty acids on cognitive status among older people: a double-blind randomized placebo-controlled study

Background

Cognitive impairment is a prevalent health problem in older people and its global prevalence tends to increase parallel to the extended life expectancy in world. The beneficial effect of ω-3 PUFAs on cognitive impairment has been demonstrated in some experimental and cohort studies. In this study we aimed to assess the effect of low dose docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) supplementation on cognitive status in the elderly.

Methods

In a double-blind, randomized placebo-controlled study, 199 individuals aged ≥65 years with normal or mild to moderate cognition impairment were assigned to receive either 180 mg of DHA plus 120 mg of EPA or placebo for 180 days. Cognitive status was assessed using Mini-Mental State Examination (MMSE) and Abbreviated Mental Test (AMT) score.

Results

MMSE and AMT scores were not different at the time of allocation [18.84 (5.37), 18.55 (5.12), (P = 0.70) and 4.81 (2.79) and 4.64 (2.77), (P = 0.67) respectively] and over 6 months between the ω-3 PUFA- and placebo- treated groups [18.57 (5.21), 18.39 (5.10), (P = 0.80) and 4.64 (2.77) and 4.48 (2.69) and (P = 0.67)]. The participants were categorized based on MMSE score into normal cognition, mild and moderate cognitive impairment. After multivariate adjustment, there was no significant difference among categorized groups regarding the ω-3 PUFA effect except in normal cognition group, that amount of decline in AMT in ω-3 poly unsaturated fatty acids (PUFAs) was less than placebo group.

Conclusions

It seems that prescription of low dose ω-3 PUFAs for 6 months had no significant beneficial effects on improvement of cognition or prevention of cognitive decline in older people.

Predicting the value of the Mini Nutritional Assessment (MNA) as an indicator of functional ability in older Iranian adults (Kahrizak elderly study)

OBJECTIVE

We aimed to investigate the appropriateness of the Mini Nutritional Assessment (MNA) in predicting functional ability in older adults.

DESIGN

Cross-sectional study.

SETTING

Participants were recruited from the Kahrizak Charity Foundation (KCF).

MEASUREMENTS

Nutritional and ability status were examined using the MNA and the Barthel Index (BI). Participants were divided according to MNA (≤ 23.5 and > 23.5).

RESULTS

Two hundred and thirty-five ≥ 60-year-old subjects were studied. The MNA and BI were positively correlated (r = 0.199; P = 0.001). The optimal cut-off point for BI with the highest sensitivity and specificity derived from the ROC curve was approximately 91.5 for males and 83.5 for females. The BI was significantly associated with MNA (odds ratio (OR): 1.89; 95% CI: 1.17-3.05, P = 0.009), mobility (OR: 6.39; 95% CI: 3.43-11.89, P < 0.001), consuming ≥ 2 servings of fruit and vegetables (OR: 2.27; 95% CI: 1.09-4.72, P = 0.02) and self-view of nutritional status (OR: 4.15; 95%CI: 1.26-13.63, P = 0.01). The sensitivity (62.9% in males; 68.2% in females) and specificity (51.4% in males and 52.9% in females) of these cut-off points justifies the appropriateness of the MNA for determining functional ability.

CONCLUSION

The MNA is potentially able to verify functional status among the elderly (as BI ≥ 91.5 with those of < 91.5 in males and ≥ 83.5 with those of < 83.5 in females) of KCF. It is suggested that this relationship should be further studied in a larger prospective population-based study.