Research Review By Novella Martinello©

Date Posted:

April 2010

Review Title:

Exercise Benefits in the Elderly – Cognition, BMD, Falls & CVD

Studies Reviewed:

  1. Etgen T, Sander D, Huntgeburth U et al. Physical Activity and Incident Cognitive Impairment in Elderly Persons. Archives of Internal Medicine 2010; 170(2): 186-193.
  2. Kemmler W, von Stengel S, Engelke K et al. Exercise Effects on Bone Mineral Density, Falls, Coronary Risk Factors, and Health Care Costs in Older Women. Archives of Internal Medicine 2010; 170(2): 179-185.

Background Information:

Cognitive impairment, including dementia, is a worldwide health problem that is most prevalent among the elderly. Physical activity has well-known benefits for many chronic diseases, and some recent studies suggest it may have a positive effect on cognitive function (1, 2); however, data is still limited and controversial. Study #1 (Etgen et al.) examined whether physical activity is associated with incident cognitive impairment.

Older age is also associated with a variety of chronic diseases which increase health care costs. Physical exercise affects many risk factors and diseases (3) and therefore can play a vital role in general disease prevention and treatment of elderly individuals, while potentially reducing health care costs. For the prevention of coronary heart disease (CHD), fracture risk, and frailty, older women should adhere to exercise programs consisting of endurance, resistance, and balance training. Because of reduced mobility or time constraints, it is unlikely that elderly individuals are willing to participate simultaneously in several different exercise programs (4). The aim of Study #2 (Kemmler et al.) - the Senior Fitness and Prevention (SEFIP) study - was to develop a multipurpose exercise program and to show its overall effectiveness in reducing fracture risk, reducing falls, and improving bone mineral density (BMD), while evaluating the 10-year CHD risk along with its effect on health care costs (HCCs).

Pertinent Results:

Study #1: Etgen et al.:
  • The absolute 6CIT (6-Item Cognitive Impairment Test) score was significantly higher in the group with no physical activity compared with the groups with moderate or high activity (a low score is preferable).
  • There was a significantly decreased risk of cognitive impairment at baseline for participants with moderate and high physical activity compared with those without physical activity at baseline.
  • The group with high physical activity at baseline showed no change in absolute 6CIT score, whereas the groups with no activity and with moderate activity developed more elevated 6CIT scores during follow-up. After they excluded participants with cognitive impairment at baseline, the incidence of new cognitive impairment among participants with no, moderate, and high activity at baseline was 13.9%, 6.7%, and 5.1%, respectively.
  • After adjusting for confounding variables, there remained a significant association with new cognitive function impairment in participants with no physical activity compared with those with moderate or high activity.
  • A subanalysis of those unimpaired at baseline revealed similar results (to reduce a potential problem of reverse causality).

Study #2: Kemmler et al.:
  • Average BMD at the lumbar spine (LS) and femoral neck significantly increased in the exercise group, whereas among the controls, BMD did not significantly change at the LS and significantly decreased at the femoral neck.
  • Significant differences existed for falls between the exercise group and controls for the 18-month intervention period. Overall fractures due to falls were twice as high in the controls than in the exercise group.
  • The 10-year CHD risk significantly improved in the exercise group compared to the control group, based on changes in high-density lipoprotein cholesterol level, low-density lipoprotein cholesterol level, and systolic and diastolic blood pressure.
  • No significant difference in health care costs between groups was observed.

Clinical Application & Conclusions:

These two studies provide additional evidence that we must get our older clients and relatives exercising regularly! To summarize the findings of these two studies…

In a general elderly population, moderate or high physical activity, compared with no physical activity, is independently associated with a lower risk of developing incident cognitive impairment after 2 years of follow-up.

A single multi-purpose exercise program of low-volume and high-intensity, designed for the elderly, improves overall fitness, maintains bone health, and reduces fall risk. This program is easily adoptable, therefore a broad implementation of this program is feasible.

Study Methods:

Study #1:
Using data from the INVADE (Intervention Project on Cerebrovascular Diseases and Dementia in the Community of Ebersberg, Bavaria) project, this study was a prospective cohort study, lasting 778 days, with 3369 German subjects over the age of 55. The INVADE study is a prospective and population-based cohort study in Germany, older than 55 years in 2001, and enrolled in the largest statutory German health insurance fund (Allgemeine Ortskrankenkasse [AOK]).

The complete investigation at baseline and after 2 years of follow-up was performed by physicians and included a standardized questionnaire, medical history, evaluation of several risk factors, a physical exam, a 12-lead electrocardiogram, and an overnight fasting venous blood sample for analysis in a central laboratory.

After the initial baseline investigation, the physician performed a physical exam on the participants every 3 months. Information on current health status, medical history, cognitive status, mood disorders, drug use, and former cardiovascular risk factors (such as BMI, smoking status, and alcohol consumption) was obtained by a structured questionnaire. Physical activity at baseline was determined by asking participants the number of days per week they performed strenuous activities.

Participants were allocated to the following 3 groups according to their level of activity: no activity (no regular physical activity), moderate activity (physical activity<3 times/ wk), and high activity (physical activity>3 times/ wk). Impairment in activities of daily living was assessed with the Barthel Index and the Modified Rankin Scale. Participants with a Barthel Index score of 100 (includes the ability to climb stairs without help and to walk 50 m) and a Modified Rankin Scale score of 0 were considered as being able to perform physical exercise.

Screening for cognitive function was performed by using the 6CIT. The 6CIT, also known as the “Short Blessed Test,” is a shortened form of The Blessed Information Memory Concentration Scale. Scores between 0 and 7 points are considered normal and scores higher than 7 are consistent with cognitive impairment. At baseline, 418 participants (10.7%) had cognitive impairment.

Study #2:
A semi-blinded, randomized 18-month controlled trial was conducted to compare the effects of an intense exercise program with a low-intensity, low-frequency control program (wellness program) on multiple risk factors and HCCs of elderly community-dwelling women. In this study, the primary goal of the wellness protocol was to positively affect well-being and to briefly introduce topics related to a healthy lifestyle and physical activity.

Participants were members of Siemens Health Insurance and consisted of 296 women randomly assigned to either the control group (a wellness program that focused on well-being and healthy lifestyle topics) or the high-intensity exercise program. All participants were supervised by trainers and kept training logs for monitoring of adherence and attendance. Apart from the exercise intervention, subjects were requested to maintain their usual lifestyle and exercise habits.

The weekly exercise program consisted of two 60-minute supervised group classes and two 20-minute home training sessions. Group classes consisted of a warm-up, static and dynamic balance training, Functional gymnastics, isometric strength training, and stretching sequences, and upper body exercises. The home training session emphasized strength and flexibility exercises. The primary outcome measures consisted of BMD at the lumbar spine (LS) and proximal femur, fall frequency (fall rate), projected 10-year CHD risk, and HCCs.

Secondary outcome measures included the number of fallers per group, number of fallers with injurious falls, and overall number of fractures per group. The variables for the 10-year CHD risk score consisted of low- and high-density lipoprotein cholesterol levels, blood pressure, smoking, and the presence of diabetes mellitus.

Study Strengths / Weaknesses:

Study #1:
This study had some weaknesses that must be considered when interpreting results. First, the definition of physical activity was based on a questionnaire/self-report instead of a more objective method.

Second, the follow-up period for cognitive decline of 2 years is somewhat short.

Third, the assessment of cognitive function was based only on the use of the 6CIT.

Fourth, a bias might have existed due to the participation rate based on voluntary participation or membership of the AOK.

Finally, due to the study design, participants with cognitive impairment at the beginning could be less likely to get involved or those participants who were lost to follow-up had a higher risk of death.

This study also had many strengths. The authors took steps to reduce the effect of potential reverse causality. This study had a large sample size, a complete data set, and the researchers adjusted their analysis for confounding variables. Participants were regularly assessed by physicians, and the longitudinal nature of this study was an asset.

Study #2:
This study possesses several strengths. The sample was a homogeneous community-dwelling group of women 65 years or older who were successfully blinded. The study duration was long enough to detect changes in physiological variables.

Potential effects of lifestyle changes, diseases, medication, and nutrition were controlled. The exercise regimen was progressively augmented during the intervention period, and the group sessions were strictly supervised by certified trainers. Group session attendance was favourable and drop-out rates were low. As well, health care costs were directly assessed rather than estimated.

Finally, the program is easily adoptable as the demands and costs for training materials were low.

Limitations of this study include low adherence to the home portion of the exercise program and the effects that the wellness program in the control group still had on certain low strain thresholds, which may have prevented significant group differences for 10-year CHD risk and HCCs.

Additional References:

  1. Barnes DE, Yaffe K, Satariano WA, Tager IB. A longitudinal study of cardiorespiratory fitness and cognitive function in healthy older adults. J Am Geriatr Soc. 2003; 51(4):459-465.
  2. Broe GA, Creasey H, Jorm AF, et al. Health habits and risk of cognitive impairment and dementia in old age: a prospective study on the effects of exercise, smoking and alcohol consumption. Aust N Z J Public Health. 1998; 22(5):621-623.
  3. DellaValle Pedersen BK, Saltin B. Evidence for prescribing exercise as a therapy in chronic disease. Scand J Med Sci Sports. 2006; 16(suppl1):3-63.
  4. Marcus R. Exercise: moving in the right direction. J Bone Miner Res. 1998; 13(12): 1793-1796.