In congestive heart failure (CHF), the heart is unable to pump out to the body all the blood returned to it by the veins. Doctors say the heart has lost some of its “contractility.” As a result, blood tends to back up into the chest, where it can interfere with breathing. Heart failure patients are thus often short of breath and easily fatigued. Blood may also back up in the feet and lower legs, resulting in swelling, called edema. A person with congestive heart failure may not provide her kidneys with blood sufficient to make urine, and so she begins to retain fluid and hence to gain weight.
As with so many other chronic illnesses common in our society, we have only a limited understanding of these phenomena, and most of the time we have no cure. In many cases, however, good treatments are available, and treated patients tend to have fewer symptoms and to live longer than those untreated. As with so many other health problems, detecting heart failure early is generally more beneficial than detecting it late, and for the person with established CHF early detection of deterioration helps to prevent progression to the point of danger. When things are getting worse, a timely adjustment in the medical regimen often helps. If a physician is aware that his patient is deteriorating, he can intervene and often turn things around.
The Value of Daily Weights
According to the American Association of Heart Failure Nurses, a good way to spot such deterioration is simply to weigh yourself daily. AAHFN, “DAILY WEIGHTS,” (undated), https://www.aahfn.org/mpage/dailyweights. The Cleveland Clinic offers these suggestions for doing this:
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Use the same scale every day
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Weigh yourself while undressed or wearing the same type of clothing
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Weigh yourself at the same time every day
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Weigh yourself after you urinate but before you eat
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Write down your weight every day. Use the calendar on the next page or another calendar/tracker.
Cleveland Clinic, “Heart Failure: Monitoring Your Weight & Fluid Intake,” (12.13.18), https://my.clevelandclinic.org/health/diseases/17243-heart-failure-monitoring-your-weight–fluid-intake.
Daily Weights and RPM: A Sampling of the Literature
When daily weights are incorporated into a remote patient monitoring service, the scales are Bluetooth-enabled, so the patient need not record the results, nor report them to a provider; these tasks are performed automatically.
It is still early to definitively assess the effectiveness of remote patient monitoring in assisting those with congestive heart failure. There have been some encouraging papers, however. For example, Chaudhry, S., Wang, Y., Concato, j., et al., Patterns of Weight Change Preceding Hospitalization for Heart Failure, 116(14) Circulation 1549-1554 (2007), https://www.ahajournals.org/doi/10.1161/CIRCULATIONAHA.107.690768, conducted a case-control study among patients with heart failure referred to a home monitoring system by managed care organizations. In a case-control study, two existing groups differing in outcome are identified and compared on the basis of some possible causal attribute. On the basis of age, sex, duration of home monitoring, heart failure severity, and baseline body weight, the investigators matched 134 case patients with heart failure hospitalization to 134 control patients without heart failure hospitalization. Within the week before hospitalization, weight patterns in case and control patients began to diverge appreciably. As compared with patients with mean weight increases of 2 pounds or less, the writers found that patients with mean increases of more than 2 and up to 5 pounds were about 2.8 times more likely to need hospitalization; those gaining more than 5 and up to 10 pounds about 4.5 times more likely to need it, and those gaining more than 10 pounds were about 7.6 times more likely to require inpatient admission. The investigators concluded that Increases in body weight are associated with hospitalization for heart failure and begin at least 1 week before admission. Daily information about patients’ body weight identifies a high-risk period during which interventions to avert decompensated (worsening) heart failure that necessitates hospitalization may be beneficial.
Consider also Koehler F, Koehler K, Deckwart O, et al. Efficacy of telemedical interventional management in patients with heart failure (TIM-HF2): a randomised, controlled, parallel-group, unmasked trial. Lancet 2018;392:1047–1057, https://pubmed.ncbi.nlm.nih.gov/30153985/. German investigators studied 1571 heart failure patients managed by remote patient monitoring over a three year and nine month period of observation. They were able to demonstrate a reduction in days lost due to unplanned cardiovascular (heart and blood vessel-related) hospital admissions and all-cause mortality (death).
By no means does this prove that using RPM in aid of daily weights will lengthen the life or improve the health of every person with congestive heart failure. It is still too early to be able to make such a statement definitively, and some studies have failed to show benefit from this approach. One group has argued that “RPM strategies are most effective for patient populations at high risk for HF [heart failure] decompensation, such as those recently hospitalized”; the group also wrote that beneficial results may be more likely with use of invasive techniques that of course entail both higher risk to the patent and higher costs to the payers than weight scales. As used here, “invasive” refers to such techniques as pulmonary artery (PA) pressures, for example. The pulmonary artery is a large blood vessel that brings blood from the heart to the lungs so it can pick up oxygen there; to measure the pressure within that vessel usually requires surgical implantation of a device in the body. Such a procedure provide very helpful information, but entails risks of infection, ruptured blood vessels, and even, on infrequent occasions, death. The authors conclude: “RPM approaches reliant on non-invasive sensors still hold great interest, given their applicability to a larger patient population and lower risks and costs relative to invasive approaches.” Bhatia A, Maddox TM. Remote Patient Monitoring in Heart Failure: Factors for Clinical Efficacy. Int J Heart Fail. 2021 Jan;3(1):31-50, https://e-heartfailure.org/DOIx.php?id=10.36628/ijhf.2020.0023#XREF_B53.
Conclusion
In sum, although we cannot yet claim that measuring and recording daily weights, and electronically transmitting the data to health professionals for analysis, will necessarily improve the health and save the lives of heart failure patients, there are early indications that these outcomes may be achieved. More research is needed, and quite possibly a more careful study of how best to identify those most likely to benefit. What does seem clear is that daily weighings are safe, inexpensive, relatively simple to do, and a logical adjunct to regular doctor visits and careful adherence to medication and dietary regimens.