Pharmacoepidemiology and disability in older adults: can medications slow the age-related decline in physical function?

Effects of Statins for Secondary Prevention on Functioning and Other Outcomes Among Nursing Home Residents

OBJECTIVES

Studies examining the effects of statins after acute myocardial infarction (AMI) excluded frail older adults, especially nursing home (NH) residents, and few examined functional outcomes. Older NH residents may benefit less from statins and be particularly susceptible to adverse drug events like myopathy-related functional decline. We evaluated the effects of statins on 1-year functional decline, rehospitalization, and death in NH residents.

DESIGN

We conducted a retrospective cohort study using 2007-2010 linked national data from Minimum Data Set (MDS) assessments, Medicare claims, and Online Survey Certification and Reporting System records.

SETTING AND PARTICIPANTS

We included US NH residents 65 years and older who were statin nonusers, were hospitalized for AMI between May 2007 and March 2010, and returned to the NH.

MEASURES

Outcomes were functional decline, death, and rehospitalization in the first year after post-AMI NH admission. New statin users were 1:1 propensity-score matched to nonusers to adjust for 92 characteristics. We estimated hazard ratios (HRs) and restricted mean survival time differences with 95% confidence intervals (CIs) comparing individuals who did vs did not initiate statin therapy after AMI hospitalization.

RESULTS

Propensity-score matching yielded a cohort of 5440 residents. Mean age was 83 years and 69% were female. Statin use was associated with a reduction in mortality (HR 0.80, 95% CI 0.73-0.87), corresponding to a mean of 15.9 (95% CI 9.9-22.0) days of extended life expectancy. No overall differences in rehospitalization (HR 1.06, 95% CI 0.98-1.14) or functional decline (HR 1.00, 95% CI 0.88-1.14) were observed.

CONCLUSIONS AND IMPLICATIONS

Statins may reduce 1-year mortality by 20% without affecting function among older NH residents who wish to live longer after AMI. During shared decision making with these patients or their representatives, clinicians should consider communicating that the average benefit of statins is 16 days of additional survival over 1 year.

Guideline-Recommended Medications and Physical Function in Older Adults with Multiple Chronic Conditions

BACKGROUND/OBJECTIVES

The benefit or harm of a single medication recommended for one specific condition can be difficult to determine in individuals with multiple chronic conditions and polypharmacy. There is limited information on the associations between guideline-recommended medications and physical function in older adults with multiple chronic conditions. The objective of this study was to estimate the beneficial or harmful associations between guideline-recommended medications and decline in physical function in older adults with multiple chronic conditions.

DESIGN

Prospective observational cohort.

SETTING

National.

PARTICIPANTS

Community-dwelling adults aged 65 and older from the Medicare Current Beneficiary Survey study (N = 3,273). Participants with atrial fibrillation, coronary artery disease, depression, diabetes mellitus, or heart failure were included.

MEASUREMENTS

Self-reported decline in physical function; guideline-recommended medications; polypharmacy (taking <7 vs ≥7 concomitant medications); chronic conditions; and sociodemographic, behavioral, and health risk factors.

RESULTS

The risk of decline in function in the overall sample was highest in participants with heart failure (35.4%, 95% confidence interval (CI) = 26.3-44.5) and lowest for those with atrial fibrillation (20.6%, 95% CI = 14.9-26.2). In the overall sample, none of the six guideline-recommended medications was associated with decline in physical function across the five study conditions, although in the group with low polypharmacy exposure, there was lower risk of decline in those with heart failure taking renin angiotensin system blockers (hazard ratio (HR) = 0.40, 95% CI = 0.16-0.99) and greater risk of decline in physical function for participants with diabetes mellitus taking statins (HR = 2.27, 95% CI = 1.39-3.69).

CONCLUSIONS

In older adults with multiple chronic conditions, guideline-recommended medications for atrial fibrillation, coronary artery disease, depression, diabetes mellitus, and heart failure were largely not associated with self-reported decline in physical function, although there were associations for some medications in those with less polypharmacy.

Gait Speed Predicts Incident Disability: A Pooled Analysis

BACKGROUND

Functional independence with aging is an important goal for individuals and society. Simple prognostic indicators can inform health promotion and care planning, but evidence is limited by heterogeneity in measures of function.

METHODS

We performed a pooled analysis of data from seven studies of 27,220 community-dwelling older adults aged 65 or older with baseline gait speed, followed for disability and mortality. Outcomes were incident inability or dependence on another person in bathing or dressing; and difficulty walking ¼ - ½ mile or climbing 10 steps within 3 years.

RESULTS

Participants with faster baseline gait had lower rates of incident disability. In subgroups (defined by 0.2 m/s-wide intervals from <0.4 to ≥ 1.4 m/s) with increasingly greater gait speed, 3-year rates of bathing or dressing dependence trended from 10% to 1% in men, and from 15% to 1% in women, while mobility difficulty trended from 47% to 4% in men and 40% to 6% in women. The age-adjusted relative risk ratio per 0.1 m/s greater speed for bathing or dressing dependence in men was 0.68 (0.57-0.81) and in women: 0.74 (0.66-0.82); for mobility difficulty, men: 0.75 (0.68-0.82), women: 0.73 (0.67-0.80). Results were similar for combined disability and mortality. Effects were largely consistent across subgroups based on age, gender, race, body mass index, prior hospitalization, and selected chronic conditions. In the presence of multiple other risk factors for disability, gait speed significantly increased the area under the receiver operator characteristic curve.

CONCLUSION

In older adults, gait speed predicts 3 year incidence of bathing or dressing dependence, mobility difficulty, and a composite outcome of disability and mortality.

Current and future pharmacologic treatment of sarcopenia

Sarcopenia is a complex multifactorial condition that can by treated with multimodal approaches. No pharmacologic agent to prevent or treat sarcopenia has been as efficacious as exercise (mainly resistance training) in combination with nutritional intervention (adequate protein and energy intake). However, performing resistance training sessions and following nutritional advice can be challenging, especially for frail, sarcopenic, elderly patients, and results remain only partial. Therefore, new pharmacologic agents may substantially reduce the functional decline in older people. This article reviews the new pharmacologic agents currently being assessed for treating sarcopenia.

Treatment strategies for sarcopenia and frailty

Sarcopenia is the key feature of frailty in older people and a major determinant of adverse health outcomes such as functional limitations and disability. Resistance training and adequate protein and energy intake are the key strategies for the management of sarcopenia. Management of weight loss and resistance training are the most relevant protective countermeasures to slow down the decline of muscle mass and muscle strength. The quality of amino acids in the diet is an important factor for stimulating protein synthesis. Vitamin D deficiency should be treated, and new pharmacologic approaches for sarcopenia are currently assessed.

Validated treatments and therapeutics prospectives regarding pharmacological products for sarcopenia

Loss of physical function in older adults may be, at least in part, explained by sarcopenia, a phenomenon characterized by a reduction in number and size of muscle fibres and by increase in interstitial fat and connective tissue. Lifestyle intervention (i.e. physical activity and nutrition) have shown to impact on sarcopenia. However, several drugs were suggested, with various levels of scientific evidence, to have an impact on muscle outcomes. In this study we reviewed the effect of six classes of drugs on sarcopenia and muscular outcomes in older adults. We decided to focus our review on two commonly drugs which have recently showed promising effects on muscular outcomes in older adults (ACE inhibitors and statins) and on four drugs whose effect on skeletal muscle was already largely studied (creatine, Growth Hormone, testosterone, estrogens and tibolone).

Clinical pharmacology in the geriatric patient

Geriatric patients are a subset of older people with multiple comorbidities that usually have significant functional implications. Geriatric patients have impaired homeostasis and wide inter-individual variability. Comprehensive geriatric assessment captures the complexity of the problems that characterize frail older patients and can be used to guide management, including prescribing. Prescribing for geriatric patients requires an understanding of the efficacy of the medication in frail older people, assessment of the risk of adverse drug events, discussion of the harm:benefit ratio with the patient, a decision about the dose regime and careful monitoring of the patient's response. This requires evaluation of evidence from clinical trials, application of the evidence to frail older people through an understanding of changes in pharmacokinetics and pharmacodynamics, and attention to medication management issues. Given that most disease occurs in older people, and that older people are the major recipients of drug therapy in the Western world, increased research and a better evidence base is essential to guide clinicians who manage geriatric patients.

Caloric restriction versus drug therapy to delay the onset of aging diseases and extend life

There are two firmly established methods of prolonging life. Calorie restriction (CR) using nutrient-rich diets to prolong life in lower animals, and life saving medications in humans to delay the development of the major diseases of middle and old age. These two approaches have different mechanisms of action. In rats, CR at 40% below ad libitum intake begun soon after weaning and continued until death, reduces body weight by about 40% and increases lifespan. There have been no lifelong CR studies performed on humans. However, in healthy adult human subjects about 20% CR over a period of 2-15 years, lowers body weight by about 20% and decreases body mass index (BMI) to about 19. This CR treatment in humans reduces blood pressure and blood cholesterol to a similar extent as the specific drugs used to delay the onset of vascular disease and so extend human life. These same drugs may act by mechanisms that overlap with some of the mechanisms of CR in retarding these pathologies and thus may have similar antiaging and life prolonging actions. Such drugs may be regarded as CR mimetics which inhibit the development of certain life shortening diseases, without the need to lower calorie intake. In developed countries, better medical care, drug therapy, vaccinations, and other public health measures have extended human life by about 30 years during the 20th century without recourse to CR, which is so effective in the rat. The percentage gain in human life expectancy during the 20th century is twice that achieved by CR in rat survival. However, rat longevity studies now use specific pathogen-free animals and start CR after weaning or later, thereby excluding deaths from infectious diseases and those associated with birth and early life. There is a need to develop CR mimetics which can delay the development of life-threatening diseases in humans. In the 21st century due to the human epidemic of overeating with a sedentary lifestyle, it may necessary to utilize CR to counter the aging effects of overweight. Since the greatest life-extending effects of CR in the rodent occur when started early in life, long-term antiaging therapy in humans should be initiated soon after maturity, when physiological systems have developed optimally.