Just 72 percent of Americans with one or more chronic conditions have internet access and only 78 percent have a mobile phone. That's compared to 89 percent and 91 percent, respectively, of those without chronic illness, according to a study by the Pew Internet and American Life project.

At the Health 2.0 conference in Santa Clara, California, Pew Research Center director Susannah Fox gave a sneak preview of the data, sharing that 45 percent of US adults are living with a chronic disease, and that those adults are actually less likely to have internet access or a mobile phone than their healthier counterparts. They are more likely to track using specialized devices like glucometers and more likely to take formal notes, but less likely to use apps or spreadsheets to track.

One difference between the internet connectivity statistic and the mobile phone statistic is whether the drop can be attributed to chronic diseases themselves, or just to other incidental factors.

"Living with a chronic condition is not a significant factor in predicting someone’s likelihood to own a cell phone," Fox wrote. "Statistical analysis shows that the gap is better explained by the fact that people with significant health challenges are more likely to be older, living in lower-income households, and reporting a lower level of formal education. Age, income, and education level are all strongly correlated with cell phone ownership."

For internet access, however, the opposite is true. Pew found that when age and education are held constant, living with a chronic disease independently increases the likelihood that someone will not have internet access.

While the difference in internet connectivity between those with and without conditions has stayed close to Pew's 2008 figure, the numbers themselves have increased. In 2008, 62 percent of chronically ill people had internet access, compared to 81 without chronic conditions. The mobile phone figure has stayed nearly constant since 2008.

Pew also found that the more chronic conditions a person had, the less likely they were to have internet access: 80 percent of adults living with one condition have internet access, compared with 61 percent of those living with two or more conditions.

Internet users with chronic health conditions behave differently online than those without. While Pew found that most Americans begin health-related internet searches at Google or another search engine, this is only true of 68 percent of those with chronic conditions, compared to 80 percent of those without. On the other hand, 20 percent of people with one or more chronic conditions started their search at a specialized site like WebMD, compared to 12 percent of healthy people.

"Federal government health websites were popular among those living with chronic conditions, such as PubMed, CDC.gov, Medline, HHS.gov, and Medicare.gov," the report says. "Health insurance websites, clinicians’ websites, as well as some specific services like iTriage, were also frequently mentioned by people living with chronic conditions."

People with chronic conditions were not very much more likely to pay for online content than those without (3 percent vs 2 percent). However, they were more likely to seek a second opinion for health information found online. Fifty-three percent said online information led them to seek help from a medical professional, compared to 41 percent of healthy people.

Pew also broke down the data by chronic condition, looking at internet use, online diagnosis, and self-tracking for people with high blood pressure, lung conditions, diabetes, heart conditions, and cancer. Interestingly, people with diabetes were both most likely self track in some way (87 percent) and least likely to have internet access (just 56 percent.) Cancer patients were on the other end of that spectrum. They were the most likely to use the Internet and the least likely to track -- both at 72 percent.