Jump in cancer diagnoses at 65 suggests many wait for Medicare

"Collectively, these results demonstrate that Medicare eligibility, an event coincident with becoming 65 years old, is associated with a rise in early-stage cancer diagnoses and a resulting survival benefit," researchers conclude in a new study. (Credit: Getty Images)

A new analysis of a national cancer database finds a bump in cancer diagnoses at age 65.

The finding suggests many people wait until they are eligible for Medicare before they seek care.

A couple of years ago, Joseph Shrager, professor of cardiothoracic surgery at Stanford School of Medicine, noticed a statistical anomaly in his practice. It seemed that patients were diagnosed with lung cancer at a surprisingly higher rate at 65 years old than, say, at 64 or 66.

“There was no reason rates should differ much between the ages of 63 and 65,” Shrager says. He talked it over with his thoracic surgeon colleagues at Stanford who said they were seeing something similar. They wondered if the jump in diagnoses might be a result of patients delaying care until they became Medicare eligible at 65.

“If this were true, and patients were delaying screenings or treatments for cancer, it could impact their survival,” Shrager says. A quick exploratory analysis of their own practices showed a twofold increase in lung cancer surgeries in 65-year-old patients compared with 64-year-olds.

“We decided to explore this, and its broader implications, in a larger population,” Shrager says.

Jump in 4 common cancer diagnoses

In a follow-up study published in Cancer, the researchers found a substantial rise nationwide in new cancer diagnoses at 65—not only for lung cancer but also for breast, colon, and prostate cancer. The four are the most common cancers in the United States.

“Essentially we showed there is a big jump in cancer diagnoses as people turn 65 and are thus Medicare-eligible,” says Shrager, the study’s senior author. “This suggests that many people are delaying their care for financial reasons until they get health insurance through Medicare.”

Researchers analyzed data from hundreds of thousands of patients 61-69 years old and diagnosed with lung, breast, colon, or prostate cancer from 2004 to 2016. The patients, identified from a national database, included 134,991 with lung cancer, 175,558 with breast cancer, 62,721 with colon cancer, and 238,823 with prostate cancer.

There was a greater jump in lung, breast, colon, and prostate cancer diagnoses at the transition from 64 to 65 than at all other age transitions, the research shows. Lung cancer rates showed a consistent increase of 3-4% each year for people aged 61 to 64, then at 65 that percentage doubled.

The increase was even more pronounced in people with colon cancer, which showed an annual growth rate of just 1-2% in the years leading up to Medicare eligibility, then jumped to nearly 15% at 65. In the years following age 65, diagnosis rates declined for all cancers, the study shows.

Health insurance matters

The study shows that insured cancer patients (lung, breast, colon, prostate) older than 65 are more likely to undergo surgical intervention, and they had lower five-year cancer-specific mortality rates than did their younger uninsured counterparts.

“Collectively, these results demonstrate that Medicare eligibility, an event coincident with becoming 65 years old, is associated with a rise in early-stage cancer diagnoses and a resulting survival benefit,” the study concludes.

The researchers proposed that a number of factors cause 61- to 64-year-olds to wait for medical treatments and screenings until Medicare eligibility kicks in.

“These individuals often lack insurance as a result of early retirement, pre-existing conditions hindering renewal, the high cost of private insurance, and other causes,” the study says, noting that 13-25% of this group of adults are uninsured or have a gap in medical coverage at some point preceding Medicare eligibility.

Previous research has shown that medical insurance is a strong predictor of receiving appropriate care, promoting earlier diagnosis, and improved outcomes, the study notes.

“If you don’t get the right screening or prompt diagnosis you are going to have lower cure rates,” Shrager says. “This study underlines the important difference that some sort of Medicare expansion could make.”

Deven Patel, a surgical resident at Cedars-Sinai Medical Center in Los Angeles who spent a year as a research fellow at Stanford, is the study’s lead author. Additional coauthors are from Massachusetts General Hospital and Stanford.

The authors have no conflicts of interest or funding sources related to this study.

Source: Stanford University