Treating Hypertension Extends Life
The first long term study (22 years) showed that for every month of treatment with chlorthalidone for high blood pressure extended life by one day. This JAMA of December 2011 showed that over 10 years this is 4 months of life extension. It has already been well established that strokes and heart attacks are reduced dramatically, and that may be much more important than longevity.
It would be much more interesting to see the long term effects of lifestyle in extending life and quality of life. The thiazide diuretics increase cholesterol, uric acid and insulin resistance and lead to side effects you would not see with lifestylel management.