Summary of Articles from the Journal of the American Geriatrics Society: July 2010, Volume 58

Reviewed, prepared, and submitted by Thomas T. Yoshikawa, MD, Editor-in-Chief, Journal of the American Geriatrics Society

Title:
Vitamin D Treatment for the Prevention of Falls in Older Adults: Systematic Review and Meta-Analysis

Authors:
Kalyani RR, Stein B, Valiyil R, et al

Summary:
Falls are common as well as being a cause of serious morbidity and mortality in older persons. Effective interventions for fall prevention still elude us. This study was a meta-analysis of 10 studies examining the impact of vitamin D therapy on reducing falls in older adults (age 71 to 92; community dwelling and institutionalized) with vitamin D deficiency (defined as serum levels of vitamin D of 30 ng/ml or less). The dose of vitamin D prescribed in these studies were 200 to 1,000 IU/day for 1 and 36 months duration with most studies including calcium supplementation. The net impact was a 14% fewer falls compared to placebo group or group receiving only calcium.

Comments:
Although there appeared to be a small but significant impact of vitamin D on reducing falls, there remains many unanswered questions. What is the optimal dose and duration of vitamin D needed to diminish the risk of falls? Would there be a beneficial effect in those older adults who are not deficient or insufficient in vitamin D levels? What would be the potential long-term adverse effects of sustained intake of vitamin D and calcium, especially in those with mild to moderate renal decompensation? Certainly, prescribing of vitamin D and calcium in those deficient in these substances is justified; however, whether these should be administered to all older adults as preventive intervention for falls is yet to be determined.

The opinions expressed are solely those of the reviewer and do not necessarily reflect those of the American Geriatrics Society or Journal of the American Geriatrics Society.


Title:
Physical Activity Over the Life Course and Its Association with Cognitive Performance and Impairment in Old Age

Authors:
Middleton LE, Barnes DE, Lui L-Y, et al

Summary:
There is ample evidence suggesting that physical activity in mid and late life decreases the risk of cognitive decline and impairment in old age. However, there are little to no studies investigating the impact of physical activity at multiple points of time on cognitive impairment in old age. As part of the Study of Osteoporotic Fractures, 9,344 women aged 65 and older (mean 71.6) self reported their physical activity level at teenage, age 30, age 50, and late life. Cognitive impairment was measured using a modified Mini Mental State Examination. Physical activity was classified as low (e.g., walking, gardening), moderate (e.g., dancing, tennis) and intense (e.g., jogging or skiing). Of the four age periods, teenage physical activity was most strongly correlated with lower risk of late-life cognitive impairment. However, physically inactive teenagers who became active later in life had a lower risk of cognitive impairment than whose who remained inactive.

Comments:
This study is limited by depending on self reports of physical activity level, which may not have been totally accurate. Moreover, those who are cognitively impaired may have provided inaccurate reports. Nevertheless, there is several physiological evidence supporting the finding that early age physical activity could promote improved cognition in later life, i.e., positive effect on synaptic plasticity and cognition of the brain; reduction of rates and severity of risk factors for cognitive impairment (diabetes mellitus, hypertension, obesity); and reduction of amyloid accumulation in animal models.

The opinions expressed are solely those of the reviewer and do not necessarily reflect those of the American Geriatrics Society or Journal of the American Geriatrics Society.

Title:
Age-Varying Association Between Statin Use and Incident Alzheimer’s Disease

Authors:
Li G, Shofer JB, Rhew IC, et al
Summary:
The role of statins in lowering the risk of Alzheimer’s disease (AD) remains controversial. This observational study attempted to determine whether the age of onset in statin therapy (early old age vs late old age) was associated with a lower risk of AD. The study also examined the influence of apolipoprotein E (APOE) e4 allele on the outcomes. A total of 3,099 participants from the Adult Changes in Thought (ACT) study were evaluated. Of these 3,099 participants, 711 were exposed to statins for a duration of 5.4 +/-3.6 years, and 263 participants developed probable AD. There was a 38% lower risk of probable AD with statin use (adjusted hazard ratio (aHR) 0.62). However, this association between statin use and AD decreased with advancing age. The aHR for younger (
Comments:
These findings suggest that the beneficial effects of statin use and decreasing the risk of AD is more likely to occur with earlier treatment with statins. Other studies have supported these findings, according to an accompanying editorial, i.e., 38 to 43% lower risk of AD or dementia during a 5-6 year follow-up period. However, a number of other confounding factors may explain these findings rather than age alone, and a prospective randomized primary prevention trial of statins for AD has yet to be done. Given, our current state of knowledge, the issues clinicians face are, if statins are effective in diminishing AD/dementia risk, at what age should the drug be started, how long should it be continued, and should all adults receive this medication or only those with risk factors for AD or other dementias?

The opinions expressed are solely those of the reviewer and do not necessarily reflect those of the American Geriatrics Society or Journal of the American Geriatrics Society.