As the year draws to a close, let’s look back at the events, inventions and ideas that drove the most prevalent health trends of 2015.

ICD-10

Most people have never heard of the International Statistical Classification of Diseases and Related Health Problems 10th Revision, aka ICD-10. But you can rest assured that all health care providers have! The rollout of ICD-10 has been the most anticipated — and feared — development in health care of late.

Why? Because diagnosis codes are used in all forms of medical billing. Over the last several years, the health care IT community and providers have been scrambling to prepare for the ICD-10 launch, which occurred in October. Most electronic health records providers accomplished the switch successfully. The real challenge was presented to providers who bill the “old-fashioned way” — on paper. The per-practice cost of transition from the system’s predecessor, ICD-9, is estimated to range between $56,000 for a small practice to $8 million for large practices. In 2016, many practices will experience workflow problems because of the transition, but most of these problems will not be visible to the general public.

Immunotherapy for Cancer

True medical breakthroughs are rare events. Yet in 2015, health leaders heralded the arrival of an entire class of medical breakthroughs: The FDA’s approval of several drugs designed to stimulate the immune system to fight cancer. Cancer treatment is traditionally based on a toxic mix of chemicals that do a fair amount of collateral damage to the body in addition to their main task of killing cancer cells.

For years, medical science has pursued “magic bullets” that target cancer with minimum effects to the healthy parts of the body. Now, the era of the magic bullet appears to have arrived. In March, the FDA approved Opdivo, a drug designed to treat non-small cell lung cancer. In October, Keytruda was approved, also for lung cancer. There are several more promising drugs in the FDA pipeline that seek approval, potentially in 2016 and in years to come. It also may well be the case that currently approved drugs will become approved for types of cancer other than lung cancer.

Wearable Devices

In June, wearable health-tracking device company Fitbit went public. This event marked the arrival of the personal health-tracking device revolution, poised to make a significant impact on the health care world. Wearable devices work on the principle of “you can’t change what you can’t measure.” Even if knowing the number of steps one takes every day does not itself improve overall health, wearable devices appear to help individuals keep health top of mind. Look for a continued expansion of the wearables market in 2016, especially the integration of health modules into existing devices such as the Apple Watch.

Electronic Cigarettes

Although the e-cigarette is not one of the newest health trends in and of itself, the scrutiny applied to the industry by government regulators this year signals that the world has stood up and started paying attention to this rapidly expanding market. In October, the CDC published a report on e-cigarette use as part of a proposal to regulate them. Whereas the report documented a rise in e-cigarette use across most age groups, the rise was most pronounced among smokers. This suggests that substantial numbers of smokers may be seeking a safer alternative to cigarettes. As cigarette smoking continues to be a leading risk factor for disease and death worldwide, the e-cigarette may provide a gateway to greater health in 2016.

David E. Williams is president of Health Business Group, a strategy consulting firm serving clients in technology-enabled health care services, pharmaceuticals, biotech, medical devices and software. He is frequently quoted in the media on the business of health care and is the author of the Health Business Blog. David sits on the board of both private health care companies and nonprofits.