The year 2016 may be remembered for important medical advances, but a glance at the headlines also offers a grim reminder of the many diseases that remain unyielding adversaries for science.

Parkinson’s disease claimed tens of thousands of Americans, including former US Attorney General Janet Reno; Maurice White (founder of Earth, Wind & Fire); and, quite possibly, Muhammad Ali. (The boxer, who suffered from Parkinson’s, died of sepsis, his family said.) Pancreatic cancer claimed the actor Alan Rickman, author Pat Conroy, and singer Sharon Jones. And former first lady Nancy Reagan was among the many who were felled by congestive heart failure.

Here are some other reminders of the hills medicine has yet to climb.

Gene Wilder, 83, Alzheimer’s disease

 
Credit: Towpilot Wikimedia (CC BY-SA 3.0)

The beloved film star quietly carried his diagnosis for three years before his death in August. His family said he’d been reluctant to sadden young fans, especially, by publicly disclosing his condition. (Pat Summitt, the legendary women’s basketball coach who went public with her diagnosis in 2011, also died of the disease this year.) Alzheimer’s remains one of science’s most agonizing mysteries, with more than 5 million Americans living with the disease. Earlier this year, the Alzheimer’s community was crushed by the failure of yet another once-promising experimental treatment.

Prince, 57, fentanyl overdose

 
Credit: Scott Penner Flickr (CC BY-SA 3.0)

Little is publicly known about how or when he first discovered fentanyl, a synthetic opioid that is 50 times more powerful than heroin, but Prince’s death coincided with a rising wave of such overdoses nationally. Last year, more than 27,000 people died from opioid-related overdoses, not including heroin — a sharp increase over 2014, and authorities say the death rate continues to climb.

Joey Feek, 40, cervical cancer

Along with her husband, Rory Feek, she was one half of the country singer duo Joey + Rory. Just a few months removed from the birth of their daughter, she was diagnosed in 2014 with cervical cancer, which kills more than 4,000 women in the US annually — though overall numbers have declined steadily with the widespread adoption of Pap tests. Targeting the HPV virus may also be helping, as some women with persistent HPV infections can, over the long term, develop cancer. Feek’s cancer was thought to have been cleared by surgery, but it returned a year after diagnosis. Her blog, which was read by millions, chronicled her cancer journey to its heartbreaking end, and continues under Rory’s pen.

Gwen Ifill, 61, uterine cancer

 
Credit: PBS NewsHour Flickr (CC BY 2.0)

Ifill, a pioneering journalist, was the first African-American woman to anchor a major news program — among many other professional distinctions. In her role as moderator of two vice presidential debates, Ifill pushed often-overlooked health topics into the discussion, most notably when she quizzed Senator John Edwards and Vice President Dick Cheney on the prevalence of AIDS among black women. Ifill was less inclined to speak publicly about her own health issues. The most common form of uterine cancer, endometrial cancer, strikes around 60,000 women annually, and the death rate is roughly the same as it was in 1985. One particularly cruel cause of the disease: pelvic radiation and chemotherapy treatment for other cancers.

Glenn Frey, 67, rheumatoid arthritis

 
Credit: Tiocfaidh ár lá 1916 Flickr (CC BY-ND 2.0)

The cofounder of the Eagles, Frey was the band’s first guitarist and, along with Don Henley, one of the principal songwriters. Media reports suggest Frey was first diagnosed with rheumatoid arthritis 15 years before his death in January, and that he also suffered from colitis. While some have speculated that Frey’s colitis was caused by arthritis medications — which can sometimes lead to bowel disease — others say he may have contracted both separately. Either way, those with rheumatoid arthritis will see in Frey’s battle a familiar theme: Powerful medications that bring relief from excruciating symptoms can also take a long-term toll. Life expectancy for those with the rheumatoid arthritis has improved in recent decades, but it remains lower than that of the general population.

Garry Shandling, 66, suspected heart attack

Heart disease remains the nation’s top killer, accounting for 1 in every 4 deaths. The causes are manifold, of course, and they are growing more elusive. In 2015, deaths from heart disease increased while all other leading causes of death remained steady or, in the case of cancer, dropped. In Shandling’s case, the exact cause of death remained unclear. Months before he died, in an appearance on Jerry Seinfeld’s “Comedians in Cars Getting Coffee,” Shandling revealed a recent diagnosis of hyperparathyroidism, a relatively rare condition which, the writer James Fallows pointed out in an essay about his experience with the condition, can increase the odds of heart disease.

Malik Isaac Taylor (aka “Phife Dawg”), 45, diabetes

 
Credit: fuseboxradio Flickr (CC BY-SA 2.0)

As a member of the iconic rap group A Tribe Called Quest, Taylor rose from his Queens, N.Y., roots to become a prominent artist. The diminutive Taylor had a soft spot for underdogs — he was a Mets fan, after all — but even commercial and financial success could not help him overcome an admitted addiction to sugar, and the health issues that followed. Taylor’s diabetes led to a kidney transplant eight years ago, and he continued to perform even as complications mounted. It’s a pernicious hallmark of diabetes: Many of those who suffer from the condition can function well enough even as their underlying conditions worsen, a reality that sometimes prevents them from seeking treatment or changing their behaviors until it is too late. To others the disease is fully invisible. More than 29 million Americans have diabetes. One quarter of them do not know it.

Bob Tedeschi can be reached at tedeschi@statnews.com
Follow Bob on Twitter @bobtedeschi

Republished with permission from STAT. This article originally appeared on December 27, 2016