New study finds unintentional weight loss often goes unrecognized by primary care physicians

Unintentional weight loss (UWL) is a common and serious problem, and according to several studies, it could be a sign—sometimes the only sign—of an underlying malignancy, such as a colorectal or pancreatic cancer.

However, physicians poorly recognize UWL. According to one study, only 40% of weight-loss cases, voluntary and involuntary, were recognized in primary care. And even when doctors recognize it, there are no evidence-based guidelines to evaluate it diagnostically.

As a first step in developing meaningful guidance for clinicians, weight researchers at University Hospitals and Case Western Reserve University have published a new paper that sets out to describe the incidence, rate of recognition, actions taken for diagnostic evaluation, and malignancy outcomes of UWL.

The paper, Recognition, diagnostic practices, and cancer outcomes among patients with unintentional weight loss (UWL) in primary care, appears in the April 21 issue of the journal Diagnosis.

“Our results show that unintentional weight loss is grossly under-recognized in primary care, though more likely to be recognized in older patients. Also, diagnostic practices among patients in whom it is recognized are variable,” said lead author Goutham Rao, MD, the Jack Medalie Professor and Chairman, Department of Family Medicine and Community Health, at University Hospitals and Case Western Reserve University School of Medicine.

“While the best approach to the problem is yet to be determined, we can recommend, at the very least, the electronic health record alert care teams to significant weight loss, so they could ask whether weight loss was intentional or about other causes.”

The researchers sifted through the electronic health records (EHRs) of 1.5 million adults at the start of 2020. About 29,500 were established primary care patients with at least two weight measurements in each of 2020 and 2021. Eventually, a group of 290 patients met the criteria for UWL, and, of those, UWL was recognized in 60 patients by their primary care doctors and unrecognized in 230 patients, for a recognition rate of only 21%.

The researchers found women were more likely to have UWL, and that this UWL was more likely to be recognized than among men, though the differences were not statistically significant. Women represented 55% of the group studied.

“A larger study may have greater power to detect significant differences,” Rao said. “UWL may be more common among women as they be more prone to causes of UWL such as depression. “Weight loss may be a sign of a range of medical, psychological and social conditions, such as a number of chronic illnesses, depression, and poverty, so it is essential to improve recognition by primary care physicians, who are on the front line of treating patients, to recognize this condition.”

Rao explained malignancy is the most common serious underlying cause of UWL. Other studies have shown that weight loss is the only sign of malignancy in roughly 35% of patients.

However, this particular study uncovered a modest number of cases of cancer among the UWL cohort (2%), including two of five patients with UWL whose UWL was not recognized.

The 12-month timeframe of this study may not have been long enough to capture all cases of cancer. In addition, the initial cohort of patients was cancer-free as researchers excluded patients with a cancer diagnosis at the outset.

“Our final cohort may simply have been at lower risk of cancer than the overall population of primary care patients,” said Rao.

“Ultimately, our results confirm a low rate of recognition of UWL across a broad spectrum of patients,” Rao said. “The seemingly simple intervention of an EHR alert for primary care doctors is currently lacking and may go a long way to improving recognition rates and identifying malignancy and other causes.”