Every month, the leadership team at the Gerontological Advanced Practice Nurses Association (GAPNA) highlights the most important published literature that impacts geriatric practice. This month, Valerie K. Sabol, PhD, MBA, ACNP, GNP, ANEF, FAANP, FAAN, GAPNA Past President (2018-2019), reviews 3 studies on obesity in older patients. The first argues against the use of BMI when diagnosing obesity in older patients. The second meta-analysis summarized how obesity and chronic pain frequently coexist in older populations, often creating a barrier to healthy aging. The last article looks at frailty in the context of BMI and waist circumference in the elderly.
Diagnosis of obesity based on body composition-associated health risks — time for a change in paradigm.
Obes Rev. 2021;22 Suppl 2:e13190
Summary: The authors of this study argue that it is time to call the fat-centric paradigm of obesity into question and to avoid the use of BMI and body fat percentage.1 Rather, obesity should be viewed as limited fat-free mass to muscle mass ratio together with a limited capacity of fat storage.
Commentary by Dr Sabol: As obesity rates among older adults have been increasing over the last several decades, advanced practice providers (APPs) and other clinicians have had to pay particular attention to weight and associated metrics to manage risk for chronic disease and disability.
For example, BMI (body weight [kg] divided by height [m2]) has been internationally accepted as a good indicator of percentage of fat mass (%FM) at the population level. More recently, however, the evolution and implementation of body composition analysis have highlighted the limitations of BMI in estimating obesity-associated health risk.
These limitations are important for APPs to understand, particularly when interpreting and translating research data into practice. For example, the obesity paradox, a medical hypothesis, has suggested that fat mass becomes less harmful or even protective with increasing age. However, this article highlights that the decrease in bone mineral content leads to a decrease in height that is associated with an overestimation (inflation) of BMI with increasing age.
Additional research suggest that the age-related redistribution of subcutaneous adipose tissue from the extremities to the trunk (and especially the visceral and ectopic fat depots), is not protective. The higher mortality at low BMI is not explained by a low fat mass, but rather by a low lean muscle mass, the review authors noted. Hence, the survival advantage of a higher BMI in older adults (ie, obesity paradox) is not explained by a protective effect of fat mass but because of a higher lean mass among patients with a higher BMI.
APPs are well-positioned to encourage healthy lifestyles among older adults, to include activities that help attain/maintain lean muscle mass, regardless of BMI.
The association between obesity and chronic pain among community-dwelling older adults: a systemic review and meta-analysis.
Geriatr Nurs. 2021;42(1):8-15
Commentary by Dr. Sabol: Obesity and chronic pain are common in older adults.
Reasons for this coexistence are multifaceted. For example, excessive body weight places extra mechanical load on body joints both directly and indirectly, which can increase the risk of joint degeneration (load-induced cartilage damage) and disorders that result in chronic pain. Weight-bearing body parts, particularly the back and lower extremities, are common sources of reported pain. And, adipose tissue contains various inflammatory cytokines (ie, C-reactive protein, interleukin 6, and tumor necrosis factor [TNF]-alpha) that cause low levels of chronic inflammation and possibly hyperalgesia.
As a result of these and other factors, APPs and other care providers should be aware that individuals who are overweight/obese tend to report higher pain sensitivity and a lower pain threshold compared with their counterparts of normal weight.
This review also identified female gender and vitamin D deficiency (ie, reduced daily sun exposure and chronic gastrointestinal states that impair vitamin D synthesis or absorption) as factors underlying the association between chronic pain and obesity. Notably, for APPs and other care providers, a dilemma exists in managing chronic pain and obesity: while physical activity is a common intervention to control weight, chronic pain can contribute to weight gain by limiting physical activity.
To achieve better health outcomes, APPs and other providers should partner with older adults to develop an individualized, tailored approach to comanage chronic pain and obesity simultaneously.
Frailty status is related to general and abdominal obesity in older adults.
Nutr Res. 2021;85:21-30.
Summary: The authors of this cross-sectional study hypothesized that the use of simple indicators of general and abdominal obesity may be combined to more accurately represent obesity and elucidated on how frailty status and its criteria are related to obesity in the elderly. A sample of 1444 older adults was included in the study and World Health Organization definitions of BMI and waist circumference (WC) were measured. The authors found that frailty was associated with higher levels of adiposity, but only when both general and abdominal obesity are present.3
Commentary by Dr Sabol: This study analyzed how general and abdominal obesity are related to frailty status among Portuguese older adults.
Frailty was established if an older adult screened positive for 3 or more of the following 5 criteria:
- Shrinking (self-reported, unintentional weight loss >4.5 kg in the prior year)
- Weakness (low hand-grip strength)
- Poor endurance and energy (self-reported exhaustion)
- Slowness (slowed walking time across a standard, unobstructed 4.6 m distance)
- Low physical activity (low energy expended per week).
As previously noted in another review, although BMI is internationally accepted as an indicator of percentage of fat mass, BMI does not reflect the percentage of lean muscle mass nor the distribution of fat mass (ie, visceral adipose tissue vs subcutaneous adipose tissue).
While body site adiposity distribution is clinically important, particularly among older adults who have age-associated changes (a progressive decrease in muscle mass and increase in fat mass), the availability of more sophisticated body composition analysis equipment may not be available in all clinical settings. Hence, exploring the link between frailty and easily obtainable anthropometric measurements (weight, height, and WC) is important to establish. Rather than using BMI alone (as a screening indicator for general obesity if >30), the inclusion of WC (as a screening indicator for abdominal obesity), is recommended; older adults presenting with both general and abdominal obesity should then be routinely screened for frailty.
Partnering with older adults to comanage the complexities of frailty and obesity will help identify individual goals and optimize care outcomes.
1. Bosy-Westphal A, Müller MJ. Diagnosis of obesity based on body composition-associated health risks — time for a change in paradigm. Obes Rev. 2021;22 Suppl 2:e13190. doi:10.1111/obr.13190
2. Qian M, Shi Y, Yu M. The association between obesity and chronic pain among community-dwelling older adults: a systematic review and meta-analysis. Geriatr Nurs. 2021;42(1):8-15. doi:10.1016/j.gerinurse.2020.10.017
3. Afonso C, Sousa-Santos AR, Santos A, et al. Frailty status is related to general and abdominal obesity in older adults. Nutr Res. 2021;85:21-30. doi:10.1016/j.nutres.2020.10.009