As we get older, we worry about becoming disabled and being a burden for others. The most common causes of long-term disability are: illnesses such as cancer, heart disease and diabetes (according to the Centers for Disease Control and Prevention, these diseases cause major limitations in daily living for more than 25 million Americans); arthritis and back pain; and lifestyle choices that lead to problems like obesity.

Harvard scientists, writing in the journal Hypertension, have added another cause to the list. High blood pressure (hypertension) is generally regarded as symptomless, but that may not necessarily be the case. One thousand participants in the Charleston Heart Study, of average age 68, were followed over the years, with assessments of blood pressure and 3 different disability scales. High blood pressure was defined as pressures over 140/90 mm Hg, or receiving antihypertensive medication; people with readings over 140/90 mm Hg in those taking medication were classified as 'uncontrolled hypertensives'.

Increases in systolic (the upper number), but not in diastolic pressure during the study were associated with reduced function on all the tests used. The presence of high blood pressure raised the risk of disability by 30%, and uncontrolled hypertension raised the risk just as much. Controlled hypertension, however, carried a risk of disability ranging from 16% to 25%, but this finding wasn't statistically significant i.e. it could be a chance finding.

This study provides yet another reason to have high blood pressure treated adequately. And it shows that hypertension isn't a totally symptomless disease!