New smartphone apps and accompanying devices, like blood glucose meters or blood pressure cuffs that send information to phones wirelessly, are putting information into patients’ hands. Some of these phones and add-on devices can get accurate readings from the body, but do they improve people’s health? Some early studies point to where they could make a difference.

Many apps say they can help people lose weight or change bad habits, but they might not be much more helpful than other approaches. A study in the Annals of Internal Medicine showed that patients who downloaded a calorie counting app, MyFitnessPal, lost minimal weight after six months, while a group instructed to pick any activities to lose weight had similar results. Similarly, a smartphone app didn’t stimulate more weight loss than other methods in an Arizona State University study, though the people using the app were more diligent about recording their weight during the eight-week trial than those using a pencil and paper.

However, people trying to lose weight with these online tools may have better success if they network with others working toward the same goal. A study from Northwestern University researchers showed that people who “friended” fellow members of an online weight loss club had better results. Once people had at least two friends, they lost an average of nearly 7 percent of their body weight in the six months of the study, compared to less than 5 percent by those who kept to themselves.

Monitoring chronic conditions

Smartphones can be useful for patients who have to monitor their body regularly to deal with an underlying condition such as diabetes.

In the New England Journal of Medicine, researchers showed that connecting blood sugar monitoring equipment to a smartphone significantly helped people with type 1 diabetes maintain proper sugar levels. These patients used an iPhone 4S that analyzed readings from a continuous glucose monitor and information that the patients entered about their meals. Algorithms on the phone used that data to determine the proper doses of sugar-regulating hormones, and wirelessly sent that information to pumps that automatically injected those hormones through a needle under the skin.

In another study, researchers in Chicago who texted reminders to people with type 1 and type 2 diabetes about healthy habits say the program has shown some early success in changing their behavior and bringing down health-care costs.

Patients with heart issues can also benefit from smartphones. AliveCor makes a plate that attaches to the back of a phone or tablet and has two electrodes that you can put on your chest or fingers to measure your heartbeat and detect irregularities. With an accompanying app, you can see a visual representation of your electrocardiogram recording and heart activity over time, and send that data to your doctor. The electrodes in AliveCor’s smartphone and tablet cases have been shown to measure heart rate and rhythm as accurately as traditional electrocardiograph equipment, according to a University of Southern California study published in the Journal of Cardiovascular Electrophysiology. An earlier study from the Cleveland Clinic showed that the technology was useful for patients who had a procedure to help with an irregular heartbeat.

Image diagnosis

The smartphone’s camera could help monitor visible conditions over time, like skin irregularities. A University of Houston professor invented an iPhone app called DermoScreen with software that determines in seconds whether a mole or lesion is likely cancerous; it requires the subject to take a photo of the spot with a magnifying glass over the camera lens. Preliminary tests have shown the device to be about as accurate as a diagnosis by a dermatologist. However, earlier apps that aimed to do similar things had mixed results. A 2013 study found that three apps incorrectly classified melanomas as benign at least 30 percent of the time.

Stanford researchers are developing a smartphone add-on to take pictures of the eye. They created a lens that attaches to a smartphone with a 3-D printed mount. People can use these adapters to capture high-quality images of the front and back of their eyes, and then use the phone to upload that information to their doctor. Two papers in the Journal of Mobile Technology in Medicine describe how this device could be especially useful in areas without good access to eye doctors. A primary care doctor without expensive imaging equipment could use the lens to take detailed photos of a patient’s eye and send that off to a specialist. Or emergency room doctors could use it to photograph a car accident victim and check for blood inside his eye. The project is still in early stages and needs additional testing

Lifestyle changes

Smartphones can also help monitor people with mental health or substance abuse issues when they might not otherwise go to a doctor.

Researchers in Wisconsin and Massachusetts found that a smartphone app helped recovering alcoholics abstain from drinking. These patients periodically filled out a survey on the app in the months after treatment, indicating certain lifestyle factors like their quality of sleep. With the patients’ permission, those surveys were sent to the counselors if they indicated a certain level of drinking risk or weren’t completed.

There is also ongoing research to test how apps can help with depression and mood disorders. For example, Dartmouth College researchers created a phone app that could track students’ habits over 10 weeks and found that these patterns matched the changes in depression, loneliness, and stress that they reported in surveys—indicating that the app is an accurate gauge (see “This Phone App Knows If You’re Depressed”).

The Takeaway:

Early studies show that smartphones can be effective at helping people with chronic conditions like diabetes and irregular heartbeats, and can be useful for mental health issues like depression or alcoholism. The benefits of using smartphones to persuade healthy people to take on new habits, like eating better or exercising more, are less clear. Clinical trials of smartphone apps and devices aimed at promoting health are still relatively new, but many are ongoing now or will start soon, says Eric Topol, a cardiologist whose recent book The Patient Will See You Now explores the role of mobile tools in health care. He believes that common conditions like hypertension, depression, and heart rhythm issues will see some of the most progress in the next year to 18 months.

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