Newly Diagnosed Diabetes: To Do or Not To Do?

As I mentioned yesterday, physical activity is a good thing while inactivity is bad, at least for our health.  But in a study published over the weekend in the Lancet, physical activity offered no additional benefit on top of intensive dietary intervention compared to usual care in newly diagnosed diabetics.  Before you tell me, "I told you so!" let's remember to look for trends, not flukes.  More specifically, I'd label this study a fluke since most all other studies demonstrate some outcome benefit from physical activity (or at least the converse/inverse, eg harm from inactivity).

In this study, the authors randomized 99 newly diagnosed diabetics to usual care, consisting of an initial dietary consult with follow up every 6 months.  248 newly diagnosed diabetics were randomized to intensive dietary intervention consisting of the same initial consult but with follow up every 3 months and monthly nursing support.  The 3rd group of 246 newly diagnosed diabetics received a pedometer-based activity program in addition to intensive dietary intervention.

What amazed me was the small percentage (1-2%) of individuals who failed to complete their assignment and/or were lost to follow up at 6 and 12 months.  In fact, diabetic control, as assessed by hemoglobin A1c (HgbA1c), worsened in those randomized to usual care while it improved in the intensive dietary intervention group.  Those randomized to activity in addition to intensive dietary intervention also demonstrated improvement in HgbA1c compared to usual care but not statistically significant to intensive dietary intervention alone.

Why was there no additional benefit gained from physical activity?  Perhaps the participants weren't active enough?  In fact, the editorialists noted that the individuals randomized to physical activity actually did participate in 30 minutes of brisk walking at least 5 days a week as encouraged.  So perhaps it was the lack of resistance exercise as noted in another recent study?  In the end, even the editorialist supported the trend of evidence demonstrating the benefit of physical activity despite being unable to explain this fluke result.